Search PubMed⌕ Search

Biomedical subjects

Simon Bergman

Publications and source records attributed to Simon Bergman.

At least 19 recordsLinked to original sources
PubMed2006

Elucidating the relationship between cardiac preload and renal perfusion under pneumoperitoneum.

INTRODUCTION: Pneumoperitoneum is associated with a well-described decrease in renal blood flow, but it remains unclear whether a decrease in cardiac preload is responsible. Our aim was to characterize the relationship between cardiac preload and renal perfusion during pneumoperitoneum. METHODS: Eleven pigs were submitted to three 30 minute study periods: 1) Baseline (n=11): no interventions, 2) Pneumoperitoneum (n=11): 12 mmHg CO2 pneumoperitoneum, 3) Preload Reduction: pneumoperitoneum and nitroglycerin infusion (n=8); or pneumoperitoneum and hemorrhage to a mean arterial pressure (MAP) of 40 mmHg (n=3). Echocardiographic measurements of left ventricular end-diastolic diameter (LVEDD) were used as an index of preload. Renal cortical perfusion (RCP) was measured using laser doppler flowmetry. RESULTS: LVEDD decreased from 4.2 +/- 0.5 to 4.1 +/- 0.6 cm (p=0.02) with pneumoperitoneum and then to 4.0 +/- 0.5 cm (p=0.03) with the addition of nitroglycerin. There was no statistically significant change in RCP with pneumoperitoneum (33.5 +/- 8.4 to 28.5 +/- 8.4 ml/min/100g tissue, p=0.2), but it decreased to 18.5 +/- 11.3 ml/min/100g tissue (p=0.001) with the addition of nitroglycerin. The correlation between RCP and LVEDD was weak (0.35, p=0.003), whereas correlation between RCP and MAP was superior (R=0.59, p<0.0001). CONCLUSIONS: While decreasing preload under extreme lab conditions also decreases RCP, simply creating a pneumoperitoneum of 12 mmHg does not. The decrease in renal blood flow associated with pneumoperitoneum is likely not solely a function of preload.

Animals↗
PubMed2006

Cytomorphology of yolk sac tumor of the liver in fine-needle aspiration: a pediatric case.

Yolk sac tumors (YST) in extragonadal locations are rare. Cytologic diagnosis of YST on fine-needle aspiration (FNA) smears may be a challenge to the cytopathologist. Further neo-adjuvant therapy may be based on cytologic diagnosis making accuracy important. We studied FNA material from a hepatic mass in a pediatric patient to further define the cytomorphologic features of hepatic YST. Features include large pleomorphic balls of tumor cells with high nuclear to cytoplasmic ratios, papillary or microglandular pattern of growth, cytoplasmic and intranuclear vacuoles, and prominent nucleoli. Positive immunohistochemical studies included alpha-fetoprotein, cytokeratin AE1/AE3, and CAM 5.2, which are useful in supporting the diagnosis. We report a pediatric patient in whom the diagnosis of hepatic YST was made by cytologic, histologic, and immunohistochemical studies. The subsequent liver biopsy was consistent with the FNA diagnosis. Our findings may further help to characterize the cytomorphologic features of this rare lesion.

Biomarkers, Tumor↗
PubMed2006

Diagnostic pitfalls associated with fine-needle aspiration biopsy in a patient with the myxoid variant of monophasic fibrous synovial sarcoma.

Synovial sarcoma (SS) is one of the most common soft tissue tumors that typically presents in the extremities of young adults, but may occur at any site and affect children during the first decade. Herein we discuss a 12-yr-old male who complained of left foot pain and plantar mass. A fine-needle aspiration biopsy of an 8 cm subcutaneous mass was performed revealing a myxoid spindle cell neoplasm. The cytologic differential diagnosis included a myxoid neurofibroma, neurothekeoma, and a myxoid sarcoma. Subsequent excision of the mass revealed a monophasic fibrous SS with myxoid features. Examination of the tissue by fluorescence in situ hybridization confirmed the presence of characteristic SS SYT gene rearrangement at chromosome 18q11.2. This case underscores that the cytologic distinction of mxyoid spindle cell tumors may be challenging. We report the cytologic features of a myxoid monophasic fibrous SS, and discuss its distinction from other benign and malignant myxoid soft tissue neoplasms.

Biopsy, Fine-Needle↗
PubMed2006

Evaluating surgical outcomes.

The study of outcomes has become essential for guiding quality of-care assessment and for clinical research. In this article, the properties and process of patient outcomes measurement are described. The limitations of traditional outcomes are discussed and contrasted with the emerging concept of "patient-centered"outcomes, measured by validated instruments to assess the effects of surgical interventions on health-related quality of life, functional status, pain, and patient satisfaction. The strengths and weaknesses of several measurement tools used in the surgical literature are evaluated. Finally, the authors introduce "composite outcomes" as a reflection of the multidimensional nature of modern patient care.

Employment↗
PubMed2006

The usefulness of cytogenetic analysis in fine needle aspirates for the histologic subtyping of sarcomas.

Conventional cytogenetic analysis performed from open biopsy tissue samples may be a useful adjunct for the histologic subtyping of bone and soft tissue sarcomas. However, its diagnostic utility in fine needle aspiration biopsy (FNAB) specimens is unclear. We retrospectively reviewed 24 consecutive FNAB bone and soft tissue sarcoma specimens, procured from 1995 to 2003, in which aspirated material was obtained for cytogenetic analysis. The study sample included eight Ewing sarcomas, six synovial sarcomas, five rhabdomyosarcomas, two myxoid liposarcomas, and one each of myxoid chondrosarcoma, osteosarcoma, and atypical lipoma. Cytogenetic analysis confirmed the t(X;18) in all six synovial sarcomas and the t(11;22) in three Ewing sarcomas. The t(2;13) was strongly suggested in one alveolar rhabdomyosarcoma. For two of these cases (both of which were synovial sarcomas), cytogenetic analysis was necessary for definitive diagnosis. While the positive cytogenetic results were supportive in the remainder, all were initially and accurately subtyped based on cytomorphology and/or immunohistochemistry. Cytogenetic analysis was noncontributory (eg no growth) in 14 sarcoma cases, but excluding the case of atypical lipoma, this did not preclude the rendering of an accurate diagnosis. Cytogenetic analysis can be performed on FNAB specimens from bone and soft tissue sarcomas and may be a useful diagnostic aid in difficult cases. However, when cell block material is available for immunohistochemistry, the majority of such cases are successfully subtyped.

Adolescent↗
PubMed2005

Is parathyroid carcinoma indeed a lethal disease?

BACKGROUND: Parathyroid carcinoma is a rare malignancy with a wide range of aggressiveness. There is no current staging system. Our primary aim was to review the presentation, diagnosis, surgical treatment, and outcomes of patients, with the goal of assessing the incidence of death related to parathyroid carcinoma. METHODS: The authors present a retrospective chart review on patients with parathyroid carcinoma from 1975 to 2004, identified by the tumor registry of a single tertiary-care center. Diagnoses were confirmed histologically, clinical and radiographical data were recorded, and statistical analyses were performed. RESULTS: Twenty-three cases were identified. The mean patient age was 54 years. The female:male ratio was 1.5:1. Follow-up ranged from 1 month to 23 years (median, 134 months). Mean preoperative calcium was 12.9 mg/dL. Median parathyroid hormone was 290 pg/mL. Two patients (9%) had an asymptomatic presentation, and five (22%) presented with a palpable neck mass. Only nine (39%) underwent initial comprehensive en-bloc resection. Median survival was 22 years. Five- and 10-year survival was 85.9% and 69.4%, respectively. Five- and 10-year survival with en-bloc resection was 90% and 67.5%, respectively. Local resection resulted in survival rates of 82.5% and 70.7%. Three of ten deaths were attributed to parathyroid carcinoma. In recurrent disease, computed tomography and scintigraphy had localization rates of 53% and 67%, respectively, with a concordance of 22%. CONCLUSIONS: Long-term survival is possible with parathyroid carcinoma. Death associated with parathyroid carcinoma was uncommon. A staging may be warranted despite the rarity of this disease.

Adult↗
PubMed2005

A global assessment tool for evaluation of intraoperative laparoscopic skills.

BACKGROUND: There is a pressing need for an intraoperative assessment tool that meets high standards of reliability and validity to use as an outcome measure for different training strategies. The aim of this study was to develop a tool specific for laparoscopic skills and to evaluate its reliability and validity. METHODS: The Global Operative Assessment of Laparoscopic Skills (GOALS) consists of a 5-item global rating scale. A 10-item checklist and 2 visual analogue scales (VAS) for competence and case difficulty were also used. During laparoscopic cholecystectomy, 21 participants were evaluated by the attending surgeon, by 2 trained observers and by self-assessment while dissecting the gallbladder from the liver bed. RESULTS: The intraclass correlation coefficient (ICC) for the total GOALS score was .89 (95% confidence interval [CI] .74 to .95) between observers, .82 (95% CI .67 to .92) between observers and attending surgeons, and .70 (95% CI .37 to .87) between participants and attending surgeons. The ICCs (observers) for the VAS (competence) and the checklist were .69 and .70, respectively. The mean total GOALS score (observers) for novices (postgraduate years [PGYs] 1 through 3) was 13 (95% CI 10.3 to 15.7) compared with 19.4 (95% CI 17.2 to 21.5) for experienced (PGY 4 through attending surgeons, P = .0006). The VAS demonstrated a difference in scores between novice and experienced participants (P = .001); however, the task checklist did not (P = .09). CONCLUSIONS: These data indicate that GOALS is feasible, reliable, and valid. They also suggest that it is superior to the task checklist and VAS for evaluation of technical skill by experienced raters. The findings support the use of GOALS in the training and evaluation of laparoscopic skills.

Clinical Competence↗
PubMed2005

Validity of the MISTELS simulator for laparoscopy training in urology.

BACKGROUND AND PURPOSE: The McGill Inanimate System for Training and Evaluation of Laparoscopic Skills (MISTELS) consists of a series of five laparoscopic exercises performed in an endotrainer box. MISTELS has been validated for use in both training and evaluation of general surgery residents in fundamental laparoscopic skills. The purpose of this study was to demonstrate the construct validity of MISTELS for urology residents. SUBJECTS AND METHODS: Seventeen participants were evaluated during performance of the five MISTELS tasks (peg transfer, pattern cutting, ligating loop, and suturing with extracorporeal and intracorporeal knots) using the standardized scoring system, which rewards both speed and precision. Participants included 13 urology residents (PGY 1-5), 1 fellow, and 3 urologists experienced in laparoscopy. Results are expressed as median (range). The Mann-Whitney U-test was used to compare MISTELS scores for 9 novice (PGY 1-4) and 8 experienced urologists (PGY 5-attending). P < 0.05 was considered statistically significant. RESULTS: The median MISTELS total normalized score for novices was 52.3 (range 15-68.9) compared with 71.7 (range 56.3-82.9) for experienced urologists (P = 0.007). Although the experienced group achieved higher scores in all five individual tasks, statistically significant differences were demonstrated for the peg transfer and intracorporeal suture tasks only. CONCLUSION: These data provide evidence for construct validity of the MISTELS system for urology residents.

Education, Medical, Graduate↗
PubMed2005

Measuring surgical recovery: the study of laparoscopic live donor nephrectomy.

Following laparoscopic donor nephrectomy (LDN), recovery has only been studied using traditional outcomes, subjective and confounded by comorbidity and psychosocial variables. The purpose of this study is to estimate surgical recovery following LDN using standardized, validated instruments and to compare this recovery profile to that obtained with traditional measures. This was a prospective study of patients undergoing LDN at a single institution between September 2001 and January 2004 (n = 35). At baseline and 4 weeks following surgery, functional exercise capacity was measured using the 6-min walk test (6MWT) and health-related quality of life was assessed with the Short Form-36 (SF-36) questionnaire, including physical component summary (PCS) and mental component summary (MCS) scores. Patients' self-assessment of recovery and time to resumption of regular activities was ascertained. At follow-up (median 29 days), patients' 6MWT was lower by a median of 30 m (p = 0.07) and PCS decreased from 57.1 to 42.3 (p = 0.0001), whereas MCS remained constant. Overall, length of stay, return to activities and patient-stated recovery were inadequate outcomes for classifying patient recovery using 6MWT and PCS as the reference standards. Four weeks following LLDN, patients have returned to baseline exercise capacity, but not baseline general physical health. Traditional measures of recovery are incomplete descriptors of recovery.

Adult↗
PubMed2004

Nasal chondromesenchymal hamartoma: report of a case and review of the literature.

The sinonasal region is the site of several hamartomatous lesions, the majority of which are mesenchymal, with vascular hamartomas predominating. The occurrence of hamartomas in the nasal cavity of infants and children is especially rare. Nasal chondromesenchymal hamartoma (NCMH) is a rare lesion of the intranasal sinuses generally diagnosed in the newborn period, with the eldest reported patient presenting at 16 years of age. This neoplasm is composed of mesenchymal-stromal and chondroid tissue in varying proportions. It is felt to be analogous to the mesenchymal hamartoma of the chest wall, a lesion of similar histology generally involving the ribs and chest wall of neonates. To the best of our knowledge, only 14 cases of NCMH have been reported to date. We report a case of NCMH in an 11-year-old boy.

Cartilage↗
PubMed2004

Esophageal aspergillosis in cytologic brushings: report of two cases associated with acute myelogenous leukemia.

Aspergillus, which commonly involves the sinonasal region and upper respiratory tract, is reported for the first time in esophageal brushings in two immunocompromised patients with a history of acute myelogenous leukemia (AML). Aspergillus species was identified in both cases in smears as scattered three-dimensional groups of fungi with 45 degrees angle branching. One case had a local esophageal noninvasive form, while the other, in addition to the esophagus, had disseminated to the spleen. Although Aspergillus is an uncommon cause of esophagitis in immunocompromised patients, its presence may be associated with an extremely poor prognosis as both expired shortly after detecting this fungus on esophageal brushings.

Adult↗
PubMed2004

E-cadherin-negative primary small cell carcinoma of the breast. Report of a case and review of the literature.

Primary small cell carcinoma of the breast is exceedingly rare, with fewer than 25 reported cases. The case presented herein is that of a 61-year-old woman with a 2.5-cm mass of the left breast. She underwent mastectomy with axillary node dissection. Histologic examination revealed sheets and nests of small, hyperchromatic, malignant cells with indistinct nucleoli and scant cytoplasm. High-grade solid and comedo ductal carcinoma in situ also was present. Two of 5 axillary lymph nodes contained metastatic disease. Immunohistochemical analysis demonstrated weak immunoreactivity for cytokeratin, neuron-specific enolase, and bcl-2. This histologic and immunohistochemical profile was consistent with that of a primary small cell carcinoma. Interestingly, this neoplasm lacked immunoreactivity for E-cadherin. E-cadherin expression has been documented in all 11 (100%) of 11 previously reported cases of primary small cell carcinoma of the breast, suggesting that this tumor is a form of ductal carcinoma. To our knowledge, this is the first reported case of E-cadherin-negative small cell carcinoma of the breast, which raises the question of a possible lobular histogenesis in some of these neoplasms.

Biomarkers, Tumor↗
PubMed2004

Nodal melanocytic nevi in sentinel lymph nodes. Correlation with melanoma-associated cutaneous nevi.

Melanocytic nevi occurring in lymph nodes create diagnostic difficulty by mimicking metastases. Few studies describe nodal nevi in sentinel lymph nodes (SLNs) excised for melanoma. We evaluated 72 cases in which patients had undergone SLN biopsy for melanoma. Lymph nodes and cutaneous melanomas were evaluated according to a standard protocol. Nodal nevi were identified in 8 patients (11%). Of these, 6 (75%) had an associated cutaneous nevus (P = .006). Of 21 patients with an associated nevus, 4 (19%) with nodal nevi had a cutaneous nevus with congenital features (P = .01). The incidence of nodal nevus correlated with a Breslow thickness greater than 2.5 mm (P = .02). Nevi were not seen in non-SLNs. Nodal nevi appear more frequently in patients with melanoma-associated cutaneous nevi, particularly if congenital features are present. The increased frequency of nodal nevi in SLNs relative to non-SLNs suggests an etiology of mechanical transport of nevus cells.

Adolescent↗
PubMed2003

Biopsy needle technique and the accuracy of diagnosis of atypical ductal hyperplasia for mammographic abnormalities.

The evaluation of mammographic abnormalities has become a substantial effort for surgeons and radiologists. The vacuum-assisted core biopsy (VACB) has been touted as a more accurate tool for the evaluation of mammographic lesions. Diagnosis of atypical ductal hyperplasia (ADH) from a percutaneous needle biopsy of the breast is associated with a significant risk of missing a significant breast lesion. We compared 2 methods of sampling with stereotactic-guided breast biopsy, 14-gauge automated gun core biopsy (AGCB) and VACB, on the accuracy of diagnosis of ADH at a single institution. All cases of ADH, without associated malignancy, found via image-guided breast biopsy of nonpalpable lesions between March 1996 and April 2002 were evaluated. VACB biopsy needles were utilized between July 1998 to April 2002 (686 patients) and 14-gauge AGCB from March 1996 to June 1998 (350 patients). The results of these biopsies were reviewed and compared to surgical biopsy and pathological records. ADH alone was found in 53 cases (5.1% of biopsies; mean age 57.9 years). Of these, 39 patients with ADH subsequently underwent wire-localized excisional biopsy. The other 14 patients were observed. VACB biopsy understaged 7 of 29 (24%) patients with ADH (all of which were DCIS), AGCB understaged 4 of 10 cases (40%) with one being invasive. Of the patients in the core biopsy group who were initially followed, 2 developed significant lesions within 3 years of follow-up in the same quadrant of the breast. If these cases are added to the AGCB group, then 50 per cent were understaged and significantly more invasive lesions were understaged than with VACB (17% vs. 0%; P = 0.018). The VACB resulted in less understaging of ADH than AGCB. However, there remains a significant risk of missing DCIS in this setting even with the VACB. Furthermore, the risk of understaging an invasive lesion is significantly lower in this setting with a VACB than an AGCB. Although the risk of understaging ADH is lower with the VACB, we continue to recommend excisional biopsy in a good-risk patient when a diagnosis of ADH is rendered via VACB biopsy.

Adult↗
PubMed2003

HER2 expression in thyroid tumors.

Similarities exist in hormone receptors of breast, prostate, and thyroid tumors. HER2 oncogene expression is known to be present in breast and prostate tumors, but conflicting data have been published about its presence in thyroid tumors. This uncertainty prompted us to examine the incidence of HER2 overexpression in normal and malignant thyroid tissue. Normal and neoplastic thyroid tissue samples from 46 female and 9 male patients were assayed for HER2 expression by immunohistochemical assay. Of the 55 total samples, 36 were from neoplasms and 19 were from benign tissues. Significant HER2 overexpression was not found in any benign or malignant thyroid tissue. Two of 6 thyroid carcinomas from male patients showed 1+ reactivity for HER2 expression on immunohistochemistry assay, but remained negative on fluorescene in sito hybridization confirmatory testing. No significant expression of HER2 was noted in benign or malignant thyroid tissue. These results cast doubt on the value of HER2 as a prognostic factor or possible target for specific antitumor therapy for thyroid cancer.

Adolescent↗
PubMed2002

Neutrophil-rich Ki-1-positive anaplastic large cell lymphoma: a study by fine-needle aspiration biopsy.

Fine-needle aspiration biopsy (FNAB) is an accurate, cost-effective method of evaluating lymphomas. The neutrophil-rich variant of anaplastic large cell lymphoma (NR-ALCL) is a rare non-Hodgkin lymphoma. To our knowledge, we present thefirst study of NR-ALCL by FNAB cytology. Histologic confirmation was available for both patients. Both cases were positive for Ki-1 (CD-30) and were either T-cell or null-cell phenotype. FNAB specimens were highly cellular with a single-cell pattern composed of pleomorphic tumor cells, "hallmark" tumor cells, and a background rich in neutrophils that occasionally obscured tumor cells. Diagnosis on FNAB is difficult owing to the rarity of this tumor, its resemblance to Hodgkin lymphoma and other non-Hodgkin lymphomas that express CD30, its similarity to an infectious process, and its occasional confusion with metastatic carcinoma and melanoma. Reproducible cytologic features usually are present, and the diagnosis can be made conclusively by FNAB in conjunction with ancillary studies.

Adult↗