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L D Thompson

Publications and source records attributed to L D Thompson.

At least 55 records · Page 3Linked to original sources
PubMed1999

Polymorphous low grade adenocarcinoma: a clinicopathologic study of 164 cases.

BACKGROUND: Polymorphous low grade adenocarcinomas (PLGA) are minor salivary gland neoplasms with a predilection for intraoral sites. METHODS: One hundred sixty-four cases of PLGA diagnosed between 1970-1994 were retrieved from the files of the Armed Forces Institute of Pathology, Washington, DC. Histologic features were reviewed, immunohistochemical studies and prognostic markers were performed, and patient follow-up was obtained. The data were analyzed statistically. RESULTS: The patients included 109 women and 55 men, ages 23-94 years (average, 57.6 years). The patients usually presented clinically with a palatal mass that ranged in size from 0.4-6 cm (average, 2.2 cm). The tumors were infiltrative and characterized by a polymorphous growth pattern, with individual tumors demonstrating multiple patterns, including solid, ductotubular, cribriform, trabecular, and single file growth. Neurotropism was identified frequently. The neoplastic cells were isomorphic with vesicular nuclei. Mitotic activity was inconspicuous. At an average of 115.4 months after presentation, approximately 97.6% of all patients were either alive or had died without evidence of recurrent disease after treatment with surgical excision only. Four patients had evidence of disease at last follow-up; three had died with evidence of tumor, and one patient was alive with tumor. CONCLUSIONS: PLGA is a neoplasm of minor salivary gland origin that must be separated from adenoid cystic carcinoma and benign mixed tumor for therapeutic and prognostic considerations. Conservative but complete surgical excision is the treatment of choice for these slow-growing tumors with a low proliferation index; adjuvant therapy does not appear to alter the prognosis.

Adenocarcinoma↗
PubMed1999

Basaloid squamous cell carcinoma of the sinonasal tract.

BACKGROUND: Basaloid squamous cell carcinoma (BSCC) is a high grade, aggressive variant of squamous cell carcinoma with a predilection for the larynx, hypopharynx, tonsils, and base of the tongue. To the authors' knowledge, BSCC originating in the nasal cavity and paranasal sinuses rarely has been reported. METHODS: Fourteen cases of BSCC involving the nasal cavity and paranasal sinuses were identified in the files of the Otolaryngic-Head and Neck Pathology Tumor Registry of the Armed Forces Institute of Pathology from 1975-1997. Clinical records and follow-up were available in all cases. Paraffin blocks were available for histochemical and immunohistochemical studies in all cases. RESULTS: There were 7 females and 7 males, ages 32-86 years (median, 66.5 years; mean, 62 years). The patients presented primarily with a mass lesion and unilateral nasal obstruction. In nine patients the tumor was confined to the nasal cavity. In three patients the tumor involved the sinuses alone and in two patients the tumor involved the nasal cavity and paranasal sinuses. Histologically, the tumors were widely invasive with a variety of growth patterns, including lobular, solid, trabecular, cribriform, and fascicular. The neoplastic infiltrate included predominantly pleomorphic, basaloid-appearing cells with hyperchromatic nuclei, inconspicuous to prominent nucleoli, and a variable amount of eosinophilic to clear-appearing cytoplasm. Mitotic figures, including atypical forms, were readily apparent as was necrosis (individual cell and comedo-type). Foci of squamous differentiation were limited in extent but were found in all cases and included squamous whorls, individual cell keratinization, and intercellular bridges. Intraepithelial dysplasia, carcinoma in situ, or invasive squamous carcinoma was present in all cases. Other histologic features included intercellular stromal hyalinization and peripheral nuclear palisading. In two cases, neural-type rosettes were found. Immunoreactivity for a variety of epithelial markers including cytokeratin (AE1/AE3/LP34), CAM 5.2, 34betaE12, CK7, and epithelial membrane antigen was present in all cases. Variable reactivity was present with vimentin, actins (smooth muscle and muscle specific), neuron specific enolase, S-100 protein, glial fibrillary acidic protein, CK20, carcinoembryonic antigen, Leu7, and Ewing's marker. Chromogranin, synaptophysin, neurofibrillary protein, leukocyte common antigen, HMB-45, desmin, and Epstein-Barr virus latent membrane protein were absent. Surgical resection was the treatment of choice. Eight patients had recurrent or persistent tumor and metastatic disease occurred in five patients. At last follow-up, 7 patients (50%) had died of disease with a median survival of 12 months from the time of diagnosis and 3 patients were alive with disease over periods ranging from 8 months-5 years. Of the 4 remaining patients, 2 were alive without disease at 1 month and 5 years, respectively, 1 patient was lost to follow-up with no evidence of tumor at 3 years, and 1 patient had died of unrelated causes with no evidence of disease. CONCLUSIONS: Sinonasal BSCC is a histologically distinct variant of squamous cell carcinoma with pathologic features and aggressive biologic behavior similar to BSCC localized to more common mucosal sites of the upper aerodigestive tract.

Adult↗
PubMed1999

Gastroesophageal reflux after repair of atrioventricular septal defect in infants with trisomy 21: a comparison of medical and surgical therapy.

BACKGROUND: Gastroesophageal reflux and dysmotility are common in children with trisomy 21. Children with trisomy 21 and congenital heart disease are at increased risk for complications of gastroesophageal reflux even after repair of their cardiac abnormalities. The optimal management of reflux in these patients is not known. METHODS: The authors studied 24 consecutive infants (5.3+/-3.1 months) with trisomy 21 and atrioventricular septal defect who had symptoms or signs of gastroesophageal reflux and a positive esophageal pH study finding early after repair of their cardiac anomaly. Ten patients were given standardized medical therapy with upright positioning during and after feedings, thickening of feedings, metoclopramide, and an H2-receptor antagonist. The other 14 underwent primary surgical management consisting of Nissen fundoplication through a minilaparotomy. RESULTS: All 10 medically treated patients required readmission within 2 weeks for complications related to reflux, including aspiration or pneumonia (n = 6), persistent failure to thrive (n = 2), and frequent apneic episodes (n = 2). No surgically treated patients had reflux-related complications requiring readmission. The total duration of hospitalization in the medically treated patients, including the initial hospitalization and the rehospitalization, was significantly longer than in patients who underwent fundoplication (35.8+/-9.8 v. 10.4+/-2.2 days, P<.001). At follow-up (24 to 56 months), all patients were alive except for 1 medically treated patient who died of aspiration pneumonia 28 days after readmission. Two medically treated patients required a Nissen, and 3 patients in the surgical group underwent redo fundoplication, all within 1 year. Three other patients in the medically treated group required a total of 8 hospitalizations for complications of reflux. No patient in either group required placement of a gastrostomy tube. Weight percentile for age was higher in surgical than medical patients. CONCLUSIONS: Infants with trisomy 21 and atrioventricular septal defect who undergo fundoplication are less likely to experience major complications of reflux early after cardiac surgery than those treated with a medical regimen of upright posture, thickened feedings, metoclopramide, and H2-receptor blockade.

Down Syndrome↗
PubMed1999

Early results of the extracardiac conduit Fontan operation.

BACKGROUND: Among the modifications of the Fontan operation, the extracardiac approach may offer the greatest potential for optimizing early postoperative ventricular and pulmonary vascular function, insofar as it can be performed with short periods of normothermic partial cardiopulmonary bypass and without cardioplegic arrest in most cases. In this study, we reviewed our experience with the extracardiac conduit Fontan operation, with a focus on early postoperative outcomes. METHODS AND RESULTS: Between July 1992 and April 1997, 51 patients (median age 4.9 years) underwent an extracardiac conduit Fontan operation. Median cardiopulmonary bypass time was 92 minutes and has decreased significantly over the course of our experience. Intracardiac procedures were performed in only 5 patients (10%), and the aorta was crossclamped in only 11 (22%). Intraoperative fenestration was performed in 24 patients (47%). There were no early deaths. Fontan failure occurred in 1 patient who was a poor candidate for the Fontan procedure. Transient supraventricular tachyarrhythmias occurred in 5 patients (10%). Median duration of chest tube drainage was 8 days. Factors significantly associated with prolonged resource use (mechanical ventilation, inotropic support, intensive care unit stay, and hospital stay) included longer bypass time and higher Fontan pressure. At a median follow-up of 1.9 years, there was 1 death from bleeding at reoperation. CONCLUSIONS: The extracardiac conduit Fontan procedure can be performed with minimal mortality and morbidity. Improved results may be related to advantages of the extracardiac approach and improved preservation of ventricular and pulmonary vascular function.

Cardiopulmonary Bypass↗
PubMed1999

Is it necessary to routinely fenestrate an extracardiac fontan?

OBJECTIVES: This study was conducted to assess the need for, and use of, fenestration of an extracardiac conduit Fontan. BACKGROUND: Fenestration of a Fontan connection has been proposed as a means of improving outcomes of single ventricle palliation. The benefit of fenestration is likely to be greatest in the early postoperative period when patients may experience increased pulmonary vascular resistance and decreased ventricular function due to the effects of cardiopulmonary bypass, aortic cross-clamping and positive pressure ventilation. However, there are potential drawbacks to fenestration. The utility of fenestration with extracardiac Fontan operation has not been determined. METHODS: Since 1992, 81 patients have undergone a modification of the Fontan procedure in which an extracardiac inferior cavopulmonary conduit is used in combination with a previously staged bidirectional Glenn anastomosis. We conducted a retrospective review of these patients. RESULTS: Fenestration was performed selectively in 32 patients (39%), including only 2 of the last 38 (5%). In seven patients, a fenestration was placed or clipped in the early postoperative period without cardiopulmonary bypass. There were two operative deaths. Prolonged (>2 weeks) pleural drainage occurred in 13 patients, 8 with fenestration and 5 without. In addition to undergoing earlier Fontan in our experience, patients who had a fenestration placed had significantly higher preoperative pulmonary vascular resistance, significantly higher common atrial pressure after Fontan and significantly lower post-Fontan systemic arterial oxygen saturation. Fontan pressure did not differ between nonfenestrated and fenestrated patients. At follow-up ranging to five years, there were two late deaths and no patients developed protein losing enteropathy. CONCLUSIONS: Fenestration is not necessary in most Fontan patients when an extracardiac conduit technique is performed as described in this article, and therefore, should not be performed routinely with the extracardiac conduit Fontan. The need for fenestration should be assessed after cardiopulmonary bypass when hemodynamics can be evaluated accurately. Fenestration can be placed and revised easily without bypass and with minimal intervention in patients with an extracardiac conduit Fontan.

Blood Vessel Prosthesis Implantation↗
PubMed1999

Exophytic and papillary squamous cell carcinomas of the larynx: A clinicopathologic series of 104 cases.

Exophytic and papillary squamous cell carcinomas (SCCs) are uncommon variants of SCC of the upper aerodigestive tract mucosa. The histomorphologic distinction between these variants has not been previously attempted or correlated with prognostic outcome. One hundred four cases of exophytic and papillary SCCs of the larynx were identified in the files of the Armed Forces Institute of Pathology from 1971 to 1991. The patients included 25 women and 79 men, aged 27 to 89 years (average 60.7 years). Patients had hoarseness at presentation, and many patients were using tobacco (n = 87) and/or alcohol (n = 49). Tumors measured up to 6 cm in greatest dimension. The larger tumors were associated with vocal cord impairment (n = 39). Histologically, the SCCs were divided into 2 growth patterns: papillary-frond (n = 12) or broad-based, exophytic (n = 92). Patients were treated with excisional biopsy, vocal cord stripping, and/or laryngectomy, in conjunction with radiation therapy (n = 70). Eighty-seven patients had no evidence of disease at last follow-up (average follow-up 8.6 years). Seventeen patients with an exophytic pattern died with disease (10 disseminated disease; 7 local disease). No patients with papillary patterns died of disease, although there had been 4 recurrences. In conclusion, patients with papillary and exophytic SCCs have a better prognosis than those with conventional SCCs, and the prognosis for those with papillary SCCs is even better.

Adult↗
PubMed1999

Mucinous cystic neoplasm (mucinous cystadenocarcinoma of low-grade malignant potential) of the pancreas: a clinicopathologic study of 130 cases.

Mucinous cystic neoplasms (MCNs) of the pancreas are uncommon tumors. The classification and biologic potential of these neoplasms remain the subject of controversy. Attempts to classify these tumors in a similar manner to ovarian MCNs remains controversial, as even histologically benign-appearing pancreatic MCNs metastasize and are lethal. One hundred thirty cases of MCNs were identified in the files of the Endocrine Pathology Tumor Registry of the Armed Forces Institute of Pathology from the years 1979 to 1993. The pathologic features, including hematoxylin and eosin staining, histochemistry, immunohistochemistry (IHC), cell cycle analysis, and K-ras oncogene determination were reviewed. These findings were correlated with the clinical follow-up obtained in all cases. There were 130 women, aged 20-95 years (mean age at the outset, 44.6 years). The patients had vague abdominal pain, fullness, or abdominal masses. More than 95% of the tumors were in the pancreatic tail or body and were predominantly multilocular. The tumors ranged in size from 1.5 to 36 cm in greatest dimension, with the average tumor measuring >10 cm. A spectrum of histomorphologic changes were present within the same case and from case to case. A single layer of bland-appearing, sialomucin-producing columnar epithelium lining the cyst wall would abruptly change to a complex papillary architecture, with and without cytologic atypia, and with and without stromal invasion. Ovarian-type stroma was a characteristic and requisite feature. Focal sclerotic hyalinization of the stroma was noted. This ovarian-type stroma reacted with vimentin, smooth muscle actin, progesterone, or estrogen receptors by IHC analysis. There was no specific or unique epithelial IHC. K-ras mutations by sequence analysis were wild type in all 52 cases tested. Ninety percent of patients were alive or had died without evidence of disease (average follow-up 9.5 years), irrespective of histologic appearance; 3.8% were alive with recurrent disease (average 10 years after diagnosis); and 6.2% died of disseminated disease (average 2.5 years from diagnosis). Irrespective of the histologic appearance of the epithelial component, with or without stromal invasion, pancreatic MCNs should all be considered as mucinous cystadenocarcinomas of low-grade malignant potential. Pancreatic MCNs cannot be reliably or reproducibly separated into benign, borderline, or malignant categories.

Adult↗
PubMed1999

A clinicopathologic and immunohistochemical study of 22 intraductal papillary mucinous neoplasms of the pancreas, with a review of the literature.

Intraductal papillary-mucinous neoplasms (IPMNs) of the pancreas are rare lesions. We undertook this study to analyze these tumors by focusing on the diagnostic criteria and correlating the histologic features with clinical prognosis. Twenty-two cases of IPMN were retrieved from the Endocrine Tumor Registry of the Armed Forces Institute of Pathology. Blocks or unstained slides were available for histochemical and immunohistochemical studies (including proliferative markers and cell cycle regulators) and K-ras oncogene mutations in 15 cases. Patient follow-up was obtained in all of the cases. IPMN occurs in both genders with a slight male predominance, with a mean age at presentation of 64.4 years (range, 48-85 yr). The patients presented with abdominal pain. The neoplasms were radiologically and grossly cystic, usually (18 cases of 22) located in the head of the pancreas. Histologically, the tumors consisted of intraductal papillary proliferations protruding into and expanding the pancreatic ducts. Invasion into the surrounding pancreatic parenchyma was detected in 15 cases. Chronic pancreatitis was present in all of the cases. p27 immunoreactivity always exceeded the immunoreactivity of cyclin E. K-ras oncogene mutations were detected in two cases. Patients were treated with a complete surgical resection (n = 7) or a Whipple procedure (n = 13). Only 2 of 22 patients died of disease (3 died immediately postoperatively and 3 died of unrelated causes), whereas the remaining 14 patients were alive at last follow-up, without evidence of disease, an average of 58.2 months after initial presentation. IPMNs are rare, distinctive neoplasms, with complex intraductal papillae, that can be easily separated from in situ ductal adenocarcinoma and mucinous cystic neoplasms. The high ratio of p27 protein to cyclin E supports the excellent prognosis of these neoplasms, despite the presence of invasion and K-ras oncogene mutation.

Aged↗
PubMed1998

A clinicopathologic and immunohistochemical study of ten pancreatic lymphangiomas and a review of the literature.

BACKGROUND: Pancreatic lymphangiomas are rare benign tumors, of which only a few cases have been reported in the literature. In this study, the authors present a series of primary pancreatic lymphangiomas. METHODS: Cases of nonepithelial pancreatic cystic tumors (lymphangiomas) diagnosed between 1966 and 1994 were retrieved from the Endocrine Pathology Registry of the Armed Forces Institute of Pathology. Histologic features (in 10 cases) as well as histochemical and immunohistochemical studies (in 6 cases) were reviewed. Long term patient follow-up data were obtained in 9 cases. RESULTS: The patients included 8 females and 2 males ages 2-61 years (mean age, 28.9 years) at initial presentation. The tumors were circumscribed and occurred predominantly (in 6 of 10 cases) in the tail of the pancreas. The multicystic, serous, or chylous fluid-filled cystic tumors ranged from 3 to 20 cm (average, 12.7 cm) in greatest dimension. Histologically, the tumors consisted of multilocular cystic spaces of various sizes, lined by endothelial cells. The stroma contained smooth muscle and mature lymphocytes. Immunohistochemistry determined the endothelial lining cells to be factor VIII-R antigen and CD31 positive (in all cases tested) but usually CD34 negative. All patients for whom follow-up data were obtained (n=9) were alive without evidence of disease an average of 7.2 years after initial diagnosis. CONCLUSIONS: Pancreatic lymphangiomas occur predominantly in females within a wide age range. Multilocular, fluid-filled cysts, with endothelial immunoreactivity for factor VIII-R antigen and CD31, are characteristic of these tumors. Complete surgical excision of these benign tumors resulted in excellent long term prognoses for all patients studied.

Adolescent↗
PubMed1998

The clinical importance of cystic squamous cell carcinomas in the neck: a study of 136 cases.

BACKGROUND: Predominantly cystic squamous cell carcinomas in the neck often present without a clinically apparent primary and therefore are frequently considered to be of branchial cleft origin. It is the authors' hypothesis that the anatomic site of the primary carcinoma that produced the neck metastasis can often be predicted on the basis of the histologic features. METHODS: Cases of cystic squamous cell carcinoma in the neck diagnosed between 1971 and 1991 were retrieved from the Otorhinolaryngic Pathology Registry of the Armed Forces Institute of Pathology. Histologic features were reviewed and patient follow-up was obtained and analyzed. RESULTS: In cases wherein the primary site was discovered subsequently, 64% of the primaries were in the lingual or faucial tonsil. An additional 8% of cases were in nasopharyngeal tonsillar tissue. The cases that did not originate in Waldeyer's tonsillar ring generally differed in histologic appearance from the tonsillar cases. The tonsillar primaries were discovered within an average of 12.4 months, but many were not discovered for years (up to 11 years). Most were small, indicating a slower growth of the primary than is usually expected for squamous cell carcinoma. Patients with such carcinomas had a much better prognosis than patients with metastatic squamous cell carcinomas of other upper airway mucosal sites. CONCLUSIONS: In most cases of prominently cystic squamous cell carcinomas in the upper neck, the origin of the primary site will be in faucial or lingual tonsillar crypt epithelium. Knowledge of the probable site of origin allows for more tailored therapy in which the patients can be treated relatively conservatively with surgical excision and subsequent field-limited radiation therapy only, with 77% survival at 5 years. None of the cases reviewed in this study was a branchiogenic carcinoma.

Adult↗
PubMed1998

Primary ameloblastoma of the sinonasal tract: a clinicopathologic study of 24 cases.

BACKGROUND: Ameloblastomas are locally aggressive jaw tumors with a high propensity for recurrence and are believed to arise from the remnants of odontogenic epithelium. Extragnathic ameloblastomas are unusual and primary sinonasal tract origin is extraordinarily uncommon. METHODS: Twenty-four cases of ameloblastoma confined to the sinonasal tract were retrieved from the Otorhinolaryngic-Head & Neck Pathology and Oral-Maxillofacial Pathology Tumor Registries of the Armed Forces Institute of Pathology between 1956 and 1996. RESULTS: The patients included 5 females and 19 males with an age range of 43-81 years, with a mean age at presentation of 59.7 years. The patients presented with an enlarging mass in the maxillary sinus or nasal cavity (n = 24), sinusitis (n = 9), or epistaxis (n = 8). Unilateral opacification of the maxillary sinus (n = 12) was the most common radiographic finding. Histologically, the tumors exhibited the characteristic features of ameloblastoma, including peripherally palisaded columnar cells with reverse polarity. The majority of the tumors showed a plexiform growth pattern. Fifteen tumors demonstrated surface epithelial derivation. Surgical excision is the treatment of choice, ranging from conservative surgery (polypectomy) to more aggressive surgery (radical maxillectomy). Five patients experienced at least 1 recurrence, usually within 1 year of initial surgery. With follow-up intervals of up to 44 years (mean, 9.5 years), all 24 patients were alive without evidence of disease or had died of unrelated causes, without evidence of disease. CONCLUSIONS: Primary ameloblastoma of the sinonasal tract is rare. In contrast to their gnathic counterparts, sinonasal tract tumors have a predilection for older age men. Therapy should be directed toward complete surgical resection to prevent local tumor recurrence.

Adult↗
PubMed1998

Thyroid papillary carcinoma of columnar cell type: a clinicopathologic study of 16 cases.

BACKGROUND: Thyroid papillary carcinoma of columnar cell type is considered an uncommon histologic subtype of papillary carcinoma characterized by its morphologic features and purportedly aggressive biologic course. METHODS: Sixteen cases of thyroid papillary carcinoma of columnar cell type were identified from the Endocrine Tumor Registry at the Armed Forces Institute of Pathology and the Washington Hospital Center. Clinical records and follow-up were available in all cases. Paraffin blocks were available for histochemical and immunohistochemical studies in 15 of the 16 cases. RESULTS: Of the 16 cases reported, 13 patients were female and 3 were male. The ages ranged from 16-76 years (average, 47 years; median, 40 years). An asymptomatic neck mass was the most common clinical presenting symptom. Macroscopically, the tumors varied from circumscribed or encapsulated to infiltrative, ranging in size from 1.5-6.5 cm. Histologically, the tumors had diverse growth patterns, including papillary, solid, microfollicular, and cribriform. A common pattern was the presence of markedly elongated follicles arranged in parallel cords. Colloid-filled follicles could be found, at least focally, in all cases. The characteristic histologic appearance included the presence of elongated cells showing nuclear stratification. Other features included the presence of vacuolated-appearing cells, spindle-shaped cells, and squamoid nests. Limited areas in the tumors showed morphologic features typical of thyroid papillary carcinoma. In 14 of the cases, the tumor was encapsulated, showed limited invasive growth, or was a microscopic tumor. In two of the cases, there was extrathyroidal invasion. Immunohistochemical studies showed consistent reactivity with cytokeratin and vimentin; varied reactivity with thyroglobulin, epithelial membrane antigen, carcinoembryonic antigen, and LeuM1; and no reactivity with calcitonin or chromogranin. Treatment was by surgical resection; supplemental radioactive iodine therapy was administered in eight patients. Follow-up was available for all patients, 13 of whom (81%) were alive and free of disease or had died of unrelated causes over periods ranging from 2-11 years (average, 5.8 years). All 13 of these patients had tumor confined completely to the thyroid gland. One patient died 4 months after diagnosis secondary to sepsis. Two patients (17%) had aggressive biologic courses. In both patients there was extrathyroidal invasion. One of these patients died of metastatic disease to the lungs 3 years after diagnosis; the other was alive with bilateral pulmonary metastases 9 years after the diagnosis. CONCLUSIONS: The findings of the current study indicate that thyroid papillary carcinoma of columnar cell type is a distinct morphologic type but not a distinct clinical type of thyroid papillary carcinoma. The biologic behavior of this tumor is predicated on clinical stage, with the presence or absence of extrathyroidal invasion being the single most important parameter. Treatment of patients with these tumors should be based on the clinical stage and not on the morphologic appearance.

Adolescent↗
PubMed1998

A rationale for conservative management of microscopic papillary carcinoma of the thyroid gland: a clinicopathologic correlation of 90 cases.

Microscopic papillary carcinoma of the thyroid gland (MPC) measuring < or = 1.0 cm in diameter has a generally benign outcome, but is often overtreated with additional surgery. Ninety cases of MPC and 77 cases of nonmicroscopic papillary carcinoma of the thyroid gland (non-MPC) from 1970 to 1980 were retrieved from the Endocrine Registry of the Armed Forces Institute of Pathology (AFIP), Washington, D.C. Histologic features and patient follow-up were analyzed. Twenty-one patients with MPC had multifocal disease within the affected thyroid lobe, while a further 15 had either bilateral or intraglandular spread. Four of 10 patients who had additional surgery were found to have additional foci of tumor. Fourteen patients with lymph node metastases at initial surgery had no subsequent nodal metastases. All patients were either alive without disease or had died of unrelated causes after an average follow-up period of 17.3 years. Of the 77 non-MPC patients, 13 developed lymph node metastases or local recurrences, and one died of metastatic disease. Sixty-four of these patients were alive without evidence of disease after an average follow-up of 22 years. Present findings show that while MPC may present with perithyroidal lymph node metastases (15.56%), patients do not develop clinical tumors in the remaining thyroid tissue. Our experience indicates that close clinical follow-up without additional surgery is the preferable management for patients with MPC.

Carcinoma, Papillary↗
PubMed1998

Resting of pigs and hot-fat trimming and accelerated chilling of carcasses to improve pork quality.

Market pigs (n = 120) were rested 0, 1, 2, or 3 h before slaughter. One carcass side was hot-fat trimmed (HFT) immediately after dressing, and the other was not fat trimmed (NFT). Sides received conventional chilling (CC) or accelerated chilling (AC) in a freezer at -32 degrees C for 100 min. Skin temperatures of live pigs decreased 5 degrees C during 3 h of rest, and resting reduced muscle temperature at .5 and 1.5 h postmortem. Early postmortem muscle pH was .3 higher if pigs were rested up to 2 h if CC was used (P < .01). Resting pigs 2 h decreased loin purge about 1% and increased cured ham yields 6% over those not rested. The AC carcasses had about .15 higher muscle pH from 4.5 to 24 h postmortem than CC carcasses (P < .03). The AC improved loin quality about 15% and lowered L values of loins and hams about 4% (P < .04). The AC substantially reduced the incidence of unacceptable quality in loins and hams, with the most effect on hams, and slightly toughened loin muscles but not cured ham muscles. Resting of pigs and AC of carcasses gave superior color of loin chops at d 0 of retail display and lowered L values during display. The HFT process improved ham quality scores about 8% but not loin scores. Resting pigs for 2 h, AC, and HFT in concert or separately are effective means of improving pork quality; AC had by far the greatest effect.

Animals↗
PubMed1998

Chilling and trimming effects on the microbial populations of pork carcasses.

The effects of chilling (normal chill or freeze chill) and trimming (hot fat trim or no fat trim) on the microbial populations of pork carcases were evaluated. In a two-part study, composited ham, loin, belly, and shoulder samples from 30 park carcasses had similar aerobic plate counts, averaging 5.5 log10 CFU/cm2. The nofat trim, normal chill procedure typically used in the industry, however, produced higher coliform and Staphylococcus spp. counts (P < 0.05). The hot fat trim, freeze chill treatment had the lowest lactic acid bacteria counts. Only 1 sample in 60 tested positive for Salmonella spp. Vacuum-packaged hams and loins stored at 4 degrees C for 14 days had similar (P > 0.05) aerobic plate counts, lactic acid bacteria and Staphylococcus spp. counts regardless of trim, chill, or the location of treatment, averaging 5.7, 6.3 and 1.4 log10 CFU/cm2, respectively. Hams had higher counts than loins all three days; however, only the difference on day 2 was significant. The desire to reduce microbial populations on pork carcasses as a food-safety issue and the coming implementation of hazard analysis critical control points (HACCP) programs warrants the use of trimming and chilling methods as critical control points or good manufacturing practices and standard operating procedures in the pork slaughter, processing, and packaging industry.

Abattoirs↗
PubMed1997

Primary smooth muscle tumors of the thyroid gland.

BACKGROUND: Primary smooth muscle tumors of the thyroid gland are rare. To date, there are few cases reported of primary thyroid leiomyomas and leiomyosarcomas. METHODS: One leiomyoma and four leiomyosarcomas arising within the thyroid gland were identified in the files of the Endocrine Tumor Registry of the Armed Forces Institute of Pathology. Histologic and immunohistochemical features were reviewed and follow-up obtained. RESULTS: The patients included 2 females, ages 56 and 64 years, and 3 males, ages 45, 68, and 83 years. The patients presented with a mass in the thyroid gland that had increased in size over a number of months. All the tumors originated within a single lobe of the thyroid gland and measured from 1.1 to 9 cm in greatest dimension. Histologically, there was a fascicular pattern of growth comprised of spindle-shaped cells with blunt-ended nuclei. The leiomyoma was encapsulated, cytologically bland, and amitotic; the leiomyosarcomas were invasive with increased cellularity, pleomorphism, a high mitotic rate, necrosis, and hemorrhage. Immunohistochemical staining showed reactivity with vimentin, smooth muscle actin, muscle specific actin, and desmin. The patient with the leiomyoma was alive without evidence of disease 11 years after the initial presentation, with surgical resection as the only treatment. Three of the patients with leiomyosarcomas were dead within 2 years of diagnosis, in spite of aggressive therapeutic intervention. The remaining patient was still alive 10 months after initial presentation with multiple lung metastases. CONCLUSIONS: Smooth muscle tumors of the thyroid gland are distinctive tumors. Leiomyosarcomas can be distinguished from anaplastic carcinoma, although patient outcome is uniformly unfavorable.

Aged↗
PubMed1997

Diagnostically challenging lesions in head and neck pathology.

There are a variety of diagnostically challenging lesions in the head and neck region. Contact ulcer usually occurs within specific clinical parameters (vocal abuse, post-intubation and gastro-esophageal reflux), which should be documented in correlation with the granulation tissue-like response affecting the posterior vocal cords. Spindle squamous cell carcinoma (carcinosarcoma) presents a variably cellular spindle cell proliferation, often with surface epithelial ulceration. The clinical presentation of a firm, polypoid mass in the larynx, combined with the histomorphologic features of a spindle cell tumor, can be confirmed to be of epithelial origin when a portion of the overlying epithelium is seen to blend with the spindle cell component, or when ancillary studies authenticate the epithelial origin of the tumor. The diagnosis of a verrucous squamous cell carcinoma can only be made accurately with an accurate clinical history. The very well differentiated histologic appearance, a broad pushing border of infiltration, a bland epithelial proliferation with scant mitotic activity and "church-spire"-type keratosis coupled with the clinical presentation of a large, locally destructive lesion, can confirm the diagnosis of verrucous carcinoma. A wide variety of disorders can result in midline destructive disease clinically, but a specific etiology must be sought to provide appropriate clinical management. Angiocentric T/NK-cell lymphoma of the sinonasal tract is one such disease. The atypical lymphoid cells are usually angiocentric and angiodestructive in their growth pattern. Identification of the atypical cells in the early stages of disease may be difficult, often requiring multiple biopsies over time with the application of immunohistochemical stains or molecular studies to accurately identify the nature of the infiltrate. Cystic squamous cell carcinoma in the neck is almost always a manifestation of metastatic tumor and not a brachiogenic carcinoma. When specific histomorphologic features are noted (a large, unfilled cyst lined by a ribbon-like or endophytic growth of a "transitional"-appearing squamous epithelium with a limited degree of anaplasia), most of these tumors demonstrate primaries in Waldeyer's ring, often of a very small size. Adequate clinical work-up (pan-endoscopy, extensive radiographic imaging and random biopsies or prophylactic tonsillectomy) is mandatory in order to limit the radiation-therapy ports and to document the location of the primary, yielding an excellent long-term prognosis.

Branchioma↗