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R S Weber

Publications and source records attributed to R S Weber.

At least 37 records · Page 2Linked to original sources
PubMed1998

Primary malignant teratoma of the thyroid gland: report and discussion of two cases.

BACKGROUND: Teratoma of the thyroid in adults is a rare neoplasm and is usually seen in young females. Most of the thyroid teratoma are malignant. The tumor appears as a dominant mass in the thyroid gland and is often associated with local lymph node involvement. We describe our experience of primary malignant teratoma of the thyroid in two young women who were treated with aggressive chemotherapy and surgical intervention. METHODS: Medical records of two patients treated between 1993 and 1995 were reviewed. Both patients were women (36 years old and 34 years old). The diagnosis of primary malignant teratoma of the thyroid was made on the basis of clinical, radiographic, and microscopic findings. Patients were treated with aggressive combination chemotherapy consisting of alternating regimens similar to those used for high-volume germ-cell tumor patients at the University of Texas M. D. Anderson Cancer Center. RESULTS: One of the patients demonstrated a partial response to chemotherapy and underwent postchemotherapy surgery for removal of residual disease. The other patient had a complete response to chemotherapy. Both patients are alive and disease free for 32- and 26-plus months. CONCLUSIONS: Primary malignant teratoma of the thyroid is sensitive to combination chemotherapy. It appears that the treatment strategy offered-aggressive induction chemotherapy with planned surgery for removal of residual disease, similar to that for patients with testicular tumors-has the potential to provide a durable, complete remission.

Adult↗
PubMed1998

Neoplastic fixation to the prevertebral compartment by squamous cell carcinoma of the head and neck.

OBJECTIVE: The purpose of this study was to determine the accuracy of MR imaging in determining fixation of squamous cell carcinomas to the prevertebral space. MATERIALS AND METHODS: MR images of 15 patients with large pharyngeal carcinoma (n = 13) or laryngeal carcinomas with pharyngeal extension (n = 2) were retrospectively reviewed independently by two head and neck radiologists who were unaware of the surgical findings. MR images were evaluated for four criteria in the prevertebral longus muscle complex: muscle concavity, irregular tumor-muscle interface, T2 hyperintensity, and enhancement. All patients underwent panendoscopy where fixation or mobility of the tumor relative to the prevertebral fascia was assessed by manual manipulation. Tumors in six patients were fixed to the prevertebral space and inoperable. In nine patients whose tumors were not fixed, open neck explorations were performed and tumors were resected in seven patients. MR findings were compared with panendoscopy in all patients and with intraoperative assessment in nine patients. RESULTS: Eleven of 15 patients had at least two of the MR imaging criteria present. None of the MR findings were both sensitive and specific for tumor fixation. Although muscle concavity and enhancement each had a sensitivity of 88%, both criteria suffered from low specificity (14% and 29%, respectively). An irregular tumor-muscle interface and muscle T2 hyperintensity were criteria that suffered from both low sensitivity and specificity. Accuracy of the imaging criteria independently ranged from 53% to 60%. CONCLUSION: Although abnormal muscle contour, T2 hyperintensity, and enhancement are frequently present in neck carcinomas that are fixed to the prevertebral space, these findings may also be present in patients in whom the tumor is mobile and resectable. MR imaging may not be able to differentiate between neoplastic fixation and nonneoplastic changes in the prevertebral space.

Adipose Tissue↗
PubMed1997

Concomitant boost radiotherapy for squamous carcinoma of the tonsillar fossa.

PURPOSE: To assess the efficacy of a concomitant boost fractionation schedule of radiotherapy for treating patients with squamous carcinoma of the tonsillar fossa. PATIENTS AND METHODS: Between December 1983 and November 1992, 83 patients with squamous carcinoma of the tonsil were treated with concomitant boost fractionation. The distribution of American Joint Committee on Cancer T stages was TX-4, T1-5, T2-29, T3-41, T4-4; N stages were NX-1, N0-26, N1-13, N2-31, N3-12. Patients were treated with standard large fields to 54 Gy in 6 weeks. The boost treatment consisted of a second daily 1.5 Gy fraction for 10-12 fractions, usually delivered during the final phase of treatment. The tumor dose was 69-72 Gy, given over 6 weeks. Twenty-one patients, who all had N2 or N3 regional disease, underwent neck dissections, either before (13 patients) or 6 weeks after radiotherapy (8 patients); the other patients were treated with radiotherapy alone. RESULTS: The 5-year actuarial disease-specific survival and overall survival rates were 71 and 60%, respectively. Patients with T2 and T3 primary tumors had 5-year actuarial local control rates of 96 and 78%, respectively. Patients with T3 disease who received the final-phase boost had a 5-year actuarial local control rate of 82%. Actuarial 5-year regional disease control rates were N0, 92%; N1, 76%; N2, 89%; and N3, 89%. The 21 patients who had neck dissections all had their disease regionally controlled. Patients presenting with nodal disease or after a node excision who were treated with radiation alone had a 5-year actuarial regional disease control rate of 79%. All but five patients had confluent Grade 4 mucositis during treatment. Severe late complications attributable to radiation included mandibular necrosis [1], in-field osteosarcoma [1], and chronic dysphagia for solid foods [5]. CONCLUSIONS: High rates of local and regional disease control were achieved with the concomitant boost fractionation schedule, with few cases of severe late morbidity. Patients with N2 and N3 neck disease were effectively treated with radiation and the selective use of neck dissections. The concomitant boost schedule is our preferred fractionation approach for treating patients with intermediate stage tonsil cancer who are not participating in our current research protocols.

Adult↗
PubMed1997

Frequency and therapeutic implications of "skip metastases" in the neck from squamous carcinoma of the oral tongue.

BACKGROUND: Supraomohyoid neck dissection is an adequate operation for the elective treatment of the neck for patients with oral cavity cancer. Squamous cell carcinoma of the oral tongue, however, metastasize to clinically negative nodes in 20% to 30% of patients. These nodes usually are located in levels I-III. METHODS: The medical records of 277 previously untreated patients with squamous cell carcinoma of the oral tongue were reviewed between the years 1970 and 1990. All patients had a glossectomy and neck dissection as part of their initial treatment. Patients were evaluated as to the findings in their neck. The following group of patients were included: (1) patients who had level III nodes positive, without disease in levels I and II; (2) patients with disease in level IV; (3) patients with disease in level IIB or IIIB, and; (4) patients who were electively dissected and whose neck did not demonstrate any pathologically involved nodes, but level IV was not included in the dissection and the patient subsequently developed pathologically positive nodes in level IV. RESULTS: Of all patients, 15.8% had either level IV metastasis as the only manifestation of disease in the neck or the level III node was the only node present without disease in level I-II. CONCLUSION: The usual supraomohyoid neck dissection is inadequate for a complete pathologic evaluation of all the nodes at risk for patients with squamous carcinoma of the oral tongue. This may create a dilemma in determining whether postoperative radiotherapy is necessary. Consequently, all patients with squamous cell carcinoma of the oral tongue should have levels I-IV nodes removed if an elective neck dissection is part of their initial therapy.

Carcinoma, Squamous Cell↗
PubMed1997

Thyroid carcinoma.

During the past years advances have been made in the understanding of the molecular mechanisms involved in the initiation and progression of thyroid carcinoma. Mutations in tumor suppressor genes such as p53 and oncogenes such as N-ras may be important for progression of well-differentiated thyroid carcinomas. Activation of the ret protooncogene located on chromosomal region 10q11.2 has been identified as a key factor in the initiation of papillary and medullary carcinoma. Integration of these discoveries into a prognostic classification scheme may allow us to better predict the biologic behavior of tumors in individual patients. Despite the recent advances in our understanding of the molecular events occurring during thyroid carcinogenesis, major questions persist regarding aspects of patient management. New diagnostic modalities may enable us to noninvasively discriminate between benign and malignant thyroid nodules, and to detect recurrent disease earlier. Although the optimal surgical procedure for well-encapsulated tumors is still debated, recent clinical studies have shown that for those patients with tumors > 1.5 cm, the routine use of RAI and hormone suppression can improve local control and survival rates. Findings in two recent reviews suggest that patients with widely invasive thyroid masses benefit from the surgical removal of all gross tumor. Further investigation is required to define the role of adjuvant radiotherapy and the most appropriate management of unresectable disease. Incorporation of prognostic markers into clinical staging systems should allow surgeons to better tailor their treatment plans for each patient. Translation of recent basic science advances into the clinical arena may also aid in the development of novel treatment strategies for patients with aggressive tumors.

Carcinoma, Medullary↗
PubMed1997

Wound infection in head and neck surgery: implications for perioperative antibiotic treatment.

Perioperative antibiotic treatment significantly reduces the risk of postoperative wound infection and is cost-effective in clean-contaminated head and neck operations. A clear consensus on the most suitable single agent or combination is, however, lacking. Most surgical wound infections involve both gram-positive and gram-negative aerobes and anaerobes; some organisms may exhibit antibiotic resistance through beta-lactamase production. Comparative trials have indicated that combinations with both aerobic and anaerobic activity provide protection superior to that achieved with single agents active against only aerobic pathogens. Recent results suggest that the beta-lactam/beta-lactamase-inhibitor combination ampicillin/sulbactam is cost-effective for perioperative treatment of patients undergoing head and neck surgery.

Anti-Bacterial Agents↗
PubMed1996

Lower gingival carcinoma. Clinical and pathologic determinants of regional metastases.

OBJECTIVE: To determine which clinical and pathologic features are associated with regional metastases in patients with lower gingival squamous cell carcinoma. PATIENTS AND METHODS: The medical charts of 155 previously untreated patients seen between 1970 and 1990 were retrospectively analyzed. All patients underwent surgical resection of the primary tumor. In addition, 66 patients underwent elective neck dissection, while a therapeutic neck dissection was performed in 28. Sixty-one patients who had clinically N0 neck disease did not undergo treatment of the cervical lymphatics. RESULTS: T stage (P = .01), radiologic (P = .03) or histologic (P = .01) evidence of mandibular invasion, and decreased tumor differentiation (P = .004) significantly correlated with the presence or evolution of regional metastases. In addition, tumors involving the symphyseal region were associated with an increased incidence of nodal metastases, although the relationship did not achieve statistical significance (P = .08). Occult regional disease was found in 18% of patients who underwent elective neck dissection, and the presence of metastases was pathologically confirmed in 68% who underwent a therapeutic dissection. Six patients with clinically N0 neck disease did not undergo elective dissection and later developed regional metastases. In all patients, survival was adversely impacted by the presence or later development of regional metastases (P < .001). Two- and 5-year survival rates for patients with no cervical metastases were 0.91 and 0.85, respectively, while for those with cervical metastases, the survival at 2 and 5 years declined to 0.72 and 0.59. More importantly, the 2- and 5-year survivals of patients with clinically N0 necks who were found to have lymph node metastases histologically after neck dissection were 1.00 and 0.78. This contrasts with the 0.50 survival rate at 2 and 5 years for those who did not undergo elective dissection and later developed cervical metastases (P = .36). CONCLUSIONS: Patients with adverse clinical and pathologic features, even in the absence of demonstrable neck disease, are at risk for harboring regional metastases. Elective treatment of the cervical lymphatics should be considered for patients with primary tumors that overlie the mandibular symphysis, moderately or poorly differentiated tumors, or radiographic or histologic evidence of mandibular invasion.

Adult↗
PubMed1996

Allergic fungal sinusitis: a clinicopathologic study of 16 cases.

Allergic fungal sinusitis (AFS) has been clinicopathologically defined as a noninvasive form of fungal infection. Etiologically, most reported cases have been attributed to pigmented dematiaceous fungi. The authors report 16 cases of AFS from our institution, along with a review of cases from the literature. The patients' age ranged from 8 to 71 years, with a mean age of 25 years. All patients were immunocompetent, although six had a strong history of atopy. Multiple sinuses were affected in all cases; nine patients had bilateral involvement, and seven patients manifested unilateral involvement. Histopathologically, all cases were characterized by the presence of "allergic mucin," with scattered fungal organisms without invasion of mucosa or bone. Fontana-Masson stain identified fungi in all but one case and assisted in distinguishing the pigmented dematiaceous organisms from other septated fungal forms. Accordingly, Fontana-Masson stain can be useful in confirming the diagnosis of AFS in the lack of tissue culture results. Fungal cultures performed on six cases grew Exserohilum (three cases), Bipolaris (one case), Drechslera (Bipolaris) (one case), and Curvularia (one case). All patients were treated with surgical debridement and sinus aeration. Follow-up of at least 6 months was obtained in six cases, of which four showed recurrent disease between 8 months and 4 years after the initial surgical procedure. A literature review showed that the most common etiologic agents were members of the dematiaceous family (81%), with the most common genus being Bipolaris (42%), followed by Curvularia (21.3%). It is believed that type I and III hypersensitivity reactions underlie the pathogenesis of this disease.

Adolescent↗
PubMed1996

Total midface reconstruction after radical tumor resection: a case report and overview of the problem.

We report an unusual repair of a massive midface defect resulting from resection of a recurrent squamous cell carcinoma of the nasal vestibule. The defect included both maxillas, the hard palate, the upper lip, and all nasal and perinasal tissues. After treatment, reconstruction was accomplished using prostheses and autologous tissue transferred from local and distant sites. The osseous component of the transferred tissue permitted placement of osseointegrated implants for fixation of maxillary and nasal prostheses. The rationale for this reconstruction and the problems associated with midface reconstruction after radical tumor resection are discussed.

Carcinoma, Squamous Cell↗
PubMed1996

Surgical management of cervical lymph node metastases.

Surgical management of regional metastases from upper aerodigestive tract malignancies has shifted from the traditional radical resection to more conservative procedures that are tailored to the extent of nodal disease and to the location of the primary tumor. When the primary tumor is treated surgically, a selective neck dissection is now performed routinely in the patient with a clinically negative neck who has a significant risk of developing regional disease. Future directions of research should emphasize clinicopathologic and molecular predictors of occult metastases in the N0 neck to allow selective, therapeutic, and cost-effective treatment of the cervical lymphatics.

Carcinoma, Squamous Cell↗
PubMed1996

Prognostic factors affecting outcome in lower gingival carcinoma.

Squamous cell carcinoma of the lower gingiva is a rare lesion that frequently invades the mandible. To determine the factors that affect local disease control and overall survival, a retrospective review of 155 previously untreated patients was performed. Primary lesions larger than 3 cm (P = .021) and persistently disease-positive surgical margins (P = .027) were found to be associated with decreased local control rates. Survival was adversely affected by advanced T stage (P = .001), positive initial and final surgical margins (P = .004), mandibular invasion (P = .014), and cervical metastases (P<.001). Extent of mandibular resection, tumor extension beyond the lower gingiva, recent dental extractions in the region of the primary, perineural invasion, and histologic grade did not affect local control or survival. Although lower gingival carcinoma tends to involve the mandible, our findings indicate that tumor size is more important than mandibular invasion in predicting local disease control. Larger tumors that have a greater propensity for local recurrence and poorer survival require a more extensive surgical resection.

Aged↗
PubMed1996

Anterior transcranial (craniofacial) resection of tumors of the paranasal sinuses: surgical technique and results.

Transfacial approaches, traditionally used for malignant tumors of the paranasal sinuses, provide limited exposure when several sinuses are involved and are unsuitable for tumors that erode through the floor of the anterior cranial fossa. A transcranial approach may aid in the removal of such lesions. To better understand the risks and benefits of this surgical approach, we reviewed all patients (n = 76) who underwent a transcranial approach as part of the excision of paranasal sinus lesions between 1984 and 1993 at our institution. The spectrum of disease included adenocarcinoma (13 patients), squamous cell carcinoma and olfactory neuroblastoma (11 patients each), adenoid cystic carcinoma and poorly differentiated forms of carcinoma (6 patients each), melanoma (5 patients), and miscellaneous others (24 patients). Most patients had ethmoid sinus involvement; tumors were also commonly found in the cribriform plate, sphenoid sinus, and nasal fossa. In each patient, a bifrontal craniotomy was performed with extradural dissection to the floor of the anterior fossa and osteotomies for resection of involved elements. In 47 patients (62%), disease in the orbit, the anterior nasal cavity, or the soft tissues of the face required transfacial as well as transcranial resections. Bony defect in the anterior fossa floor was repaired with a pedicled pericranial flap. Patients with major complications included six patients with epipericranial and/or epidural hematomas requiring evacuation, three with transient cerebrospinal fluid leaks, two who developed bifrontal cerebral infarcts, and one who died soon after surgery. No meningitis was seen. To date, 26 patients (34%) have died; of those living (mean follow-up, 34 mo), 42 (84%) remain in full remission. The transcranial approach can achieve removal of erosive, invasive tumors from this area with predictable morbidity and may be considered whenever sinus tumors breach the anterior cranial base or extend beyond the reach of conventional transfacial approaches.

Adolescent↗
PubMed1996

The vermilion-sharing graft for repairing a vermilionectomy defect.

Lower lip vermilionectomy defects can be repaired with a full-thickness graft of vermilion from the upper lip. The graft width should be approximately one-half that of the lower lip defect, sharing the vermilion between the two lips. The graft should be oriented so that the red, anterior part of the vermilion is placed anteriorly, where it will be most visible. If graft "take" is successful, the result can be aesthetically and functionally excellent, while the donor-site morbidity is minimal.

Aged↗
PubMed1995

p53 mutations in nonmelanoma skin cancer of the head and neck: molecular evidence for field cancerization.

Multiple and distinct p53 mutations were detected by DNA sequence analysis in tumor and adjacent nonmalignant skin samples from eight patients with nonmelanoma skin cancer of the head and neck, providing unambiguous evidence for field cancerization. The mutations consisted of C-->T transitions at dipyrimidine sequences (30% of all single base substitutions), T-->C transitions (47%), and G-->T transversions (12%), suggesting that other carcinogens may act along with UV radiation in the development of nonmelanoma skin cancer. Patient interviews revealed that, in addition to substantial exposure to solar UV radiation, most had a history of smoking and were exposed to carcinogens from industrial or agricultural sources. These data show that extensive molecular epidemiological investigations are necessary to elucidate risk factors associated with the disease in localities where patients often report substantial exposure to environmental carcinogens.

Adult↗
PubMed1995

Sequential p53 mutation analysis of pre-invasive and invasive head and neck squamous carcinoma.

Single-stranded conformational polymorphism (SSCP) and direct sequencing were performed on uninvolved mucosa, severe dysplasia and invasive carcinoma samples from 20 patients with head and neck squamous carcinoma. Seven (35%) of the non-invasive lesions and 15 (75%) of the invasive carcinomas manifested p53 mutations. Although the majority of mutations were mis-sense, resulting in single amino acid substitution, a silent mutation encoding for the same amino acid and 2 non-sense mutations encoding a stop codon were also observed. Mutations in invasive carcinoma were mostly in exon 8 and involved codons 296, 288 and 298; non-invasive lesions showed more mutations at exons 5 to 7. Five lesions showed simultaneous mutations in 2 different exons; in 3 both non-invasive and invasive carcinomas showed primary mutation at exons 5 to 7, and invasive carcinoma showed a secondary mutation at exon 8. Different codon mutations in the same exon between dysplastic and the corresponding carcinoma samples were found in 2 cases. p53 alterations were not observed in any of the normal mucosa samples. No apparent association between p53 mutations and conventional clinicopathologic parameters, including DNA content, was found in this cohort. Our study indicates that (i) p53 alteration is an early event in the genesis of a subset of head and neck squamous carcinomas, (ii) normal mucosa within the resected specimens lacked p53 mutation, (iii) sequential mutations of different exons of the p53 gene suggests accumulation of genetic alterations during the neoplastic transformation of these lesions and (iv) the difference in codon mutation of the same exon between dysplastic and corresponding carcinoma suggests an independent clonal development.

Adult↗
PubMed1995

The influence of positive margins and nerve invasion in adenoid cystic carcinoma of the head and neck treated with surgery and radiation.

PURPOSE: Surgery is the primary treatment for adenoid cystic carcinomas arising from major and minor salivary glands of the head and neck. However, local recurrence is frequent because of the infiltrative growth pattern and perineural spread associated with these tumors. At UTMDACC, we have had a longstanding policy of using postoperative radiotherapy to reduce the risk of local recurrence and to avoid the need for radical surgery; this 30-year retrospective study analyzes the results of this combined modality approach. METHODS AND MATERIALS: Between 1962 and 1991, 198 patients ages 13-82 years, with adenoid cystic carcinomas of the head and neck, received postoperative radiotherapy for known or suspected microscopic residual disease following surgery. Distribution of primary sites was: parotid: 30 patients; submandibular/sublingual: 41 patients; lacrimal: 5 patients; and minor salivary glands: 122 patients. Eighty-three patients (42%) had microscopic positive margins and an additional 55 (28%) had close (< or = 5 mm) or uncertain margins. One hundred thirty-six patients (69%) had perineural spread with invasion of a major (named) nerve in 55 patients (28%). Using radiation techniques appropriate to the primary site, a median dose of 60 Gy (range 50-69 Gy) was delivered to the tumor bed. Follow-up ranged from 5-341 months (median, 93 months). All surviving patients had a minimum of 2 years follow-up. RESULTS: Twenty-three patients (12%) had local recurrences with 5-, 10-, and 15-year actuarial local control rates of 95%, 86%, and 79%, respectively. Fifteen of the 83 patients (18%) with positive margins developed local recurrences, compared to 5 of 55 patients (9%) with close or uncertain margins, and 3 of 60 patients (5%) with negative margins (p = 0.02). Patients with and without a major (named) nerve involved had crude failure rates of 18% (10 out of 55) and 9% (13 out of 143), respectively (p = 0.02). There was a trend toward better local control with increasing dose. This was significant in patients with positive margins, in whom crude control rates were 40 and 88% for doses of < 56 Gy and > or = 56 Gy, respectively (p = 0.006). Actuarial 5-, 10-, and 15-year freedom from relapse rates were 68%, 52%, and 45%, respectively. Base of skull and neck failures were uncommon with or without elective treatment, developing in 2 and 3% of patients, respectively. Distant metastases were the most common type of disease recurrence, developing in 74 patients (37%) of whom 62 (31%) were disease-free at the primary site. CONCLUSIONS: Excellent local control rates were obtained in this population using surgery and postoperative radiotherapy and we recommend this combined approach for most patients with adenoid cystic carcinomas of the head and neck. Perineural invasion was an adverse prognostic factor only when a major (named) nerve was involved. Microscopic positive margins was also an adverse prognostic factor, but even when present, local control was achieved in over 80% of our patients. We recommend a dose of 60 Gy to the tumor bed, supplemented to 66 Gy for patients with positive margins. Despite effective local therapy, one-third of patients fail systemically, and good treatment to address this problem is lacking.

Actuarial Analysis↗