Significance of tumor capsular invasion in well-differentiated thyroid carcinomas.

This study examines the influence of tumor capsular invasion on the biological behavior of papillary (PTC) and follicular thyroid carcinoma (FTC) and the prognosis of surgically treated patients. This retrospective cohort study included 350 cases of PTC or FTC from a university teaching hospital. Patient charts were randomly selected and reviewed. The study population was divided into PTC and FTC groups. Each group was subdivided into CI+ (with tumor capsular invasion) and CI- subgroups (without tumor capsule or without capsular invasion). The long-term prognosis was assessed using the American Joint Committee on Cancer pTNM staging and the prognostic index was elaborated by the European Organization for Research and Treatment of Cancer. There were 284 women and 66 men (ages 19-89 years, mean of 44) with an incidence of 53.1 per cent for CI+ tumors. There were no significant differences between the PTC subgroups regarding the short-term clinical outcome and the long-term prognosis. Although patients with CI+ FTC showed lower incidence of lymph node metastasis than patients with CI- FTC, the FTC subgroups were comparable regarding the short-term clinical outcome and the long-term prognosis. Our results suggest that presence of tumor capsular invasion does not adversely influence biological behavior or survival of PTC or FTC. Moreover, the presence of tumor capsular invasion appears to not have significance for the long-term prognosis of patients with PTC or FTC.

Wilfred Trotter: surgeon, philosopher.

There is no significant biography that records the accomplishments of Sir Wilfred Trotter, who was a general surgeon in its pure sense at a time when surgical specialization was in its infancy. Trotter was born in the 1870s in England. Despite being bedridden during his childhood with a musculoskeletal condition he was able to study medicine at London University, and eventually became Professor and Chair of Surgery at the University College Hospital, a position he held until his death in November 1939. He made many contributions to surgical care, particularly in the field of oncology. He attended to many famous people, including King George V and Sigmund Freud and was greatly honoured in his own milieu. He was named honorary surgeon and Sargent Surgeon to the king. In addition, he was a thoughtful individual who addressed problems in human behaviour, contradicting the stereotype of the contemporary surgeon.

Single versus sequential fine-needle aspiration biopsy in the management of thyroid nodular disease.

UNLABELLED: Fine-needle aspiration biopsy (FNAB) is considered a safe, reliable and cost-effective means of selecting thyroid nodules with risk for malignancy. However, there are limitations of this method including false positive/negative and "nondiagnostic" results that may be reduced by repeating FNAB. OBJECTIVE: To evaluate accuracy, sensitivity, specificity and costs of sequential FNAB in the management of thyroid nodular disease. METHODS: Charts of all patients who underwent thyroidectomy at a university teaching hospital in Toronto from 1998 to 2000 were reviewed. FNAB reports of "suspicious for malignancy," "follicular lesion" and "cellular atypia" were considered to be positive. Data were analyzed with chi2 and z tests. RESULTS: There were 268 patients (225 women and 43 men; age range 18-89 yr; mean age 47 yr) who underwent a total of 449 FNABs (mean 1.7 FNABs/patient) within a year before thyroidectomy. Accuracy (63.8%), sensitivity (73.8%) and specificity (69%) were determined for single FNABs. Sequential FNAB increased the accuracy of method by 22.6%, sensitivity by 13.8% and specificity by 6.2%, with reduction of false positive/negative results by 14.2% and "nondiagnostic" results by 100%. However, the costs of sequential cytology per patient were 70% higher than single FNAB. CONCLUSIONS: Multiple FNABs are unpleasant for patients, but useful in the selection for treatment of patients with thyroid nodular diseases. Although sequential FNAB increases the costs of method, the improvement of precision of FNAB may imply a reduction in overall health-care costs.

Role of fine-needle aspiration biopsy and frozen section in the management of papillary thyroid carcinoma subtypes.

Since fine-needle aspiration biopsy (FNAB) was introduced, the value of frozen section (FS) has been questioned. This study compares FNAB and FS sensitivities among the usual form of papillary thyroid cancer (uPTC) and variants of PTC such as tall cell (tcPTC), follicular (fPTC), and Hurthle cell (HcPTC). A total of 257 patients who underwent preoperative FNAB, intraoperative FS, and thyroidectomy for PTC were, randomly selected from a database of a university teaching hospital in Toronto. There were 218 females (84.8%) and 39 males (15.2%), from 19 to 89 years of age (mean of 44 years), having uPTC (n = 212), fPTC (n = 24), HcPTC (n = 14), and tcPTC (n = 7). Data were analyzed using chi2 test. Sensitivities were calculated by division of true positives and by the sum of true positives and false negatives. True positives had to reflect a conclusive diagnosis of cancer. The FNAB sensitivities were uPTC (39.2%), fPTC (25%), HcPTC (42.9%), tcPTC (85.7%), similar to FS sensitivities (p = 0.497) for uPTC (44.3%), fPTC (16.7%), HcPTC (42.9%), and tcPTC (71.4%). Use of FS following FNAB increased sensitivities for uPTC to 56.1%, fPTC to 29.2%, and tcPTC to 100%. In addition, FS did not increase FNAB sensitivity in HcPTC. Combination FNAB plus FS failed in 43.9% of uPTC, 70.8% of fPTC, and 57.1% of HcPTC. We concluded that FNAB and FS sensitivity vary with PTC subtype and are still necessary for selection and treatment. The recognition of morphologic subtypes of PTC from the FNAB could optimize the selection of patients for intraoperative FS, enhance the preoperative assessment of prognosis, facilitate the surgical planning, and simplify the preparation of postoperative adjuvant therapy.

Thyroid colloid nodules diagnosed by fine-needle aspiration: efficacy of suppression.

BACKGROUND: This study reviewed the accuracy of fine-needle aspiration biopsy (FNAB) and the efficacy of thyroid suppression for colloid nodules in our population to determine the utility of these two modalities on the decision to operate. METHODS AND MATERIALS: A retrospective chart review of patients with colloid nodules diagnosed by FNAB from January 1993 to July 1995 was conducted. A 52-patient cohort underwent surgical management, and their needle aspirate cytologies and final pathologies were reviewed. RESULTS: A 7.7% false-negative rate in the detection of thyroid malignancy by FNAB was obtained. This is in keeping with data reported in the literature. Virtually no efficacy of hormonal suppression in our population was found. CONCLUSION: When the literature is reviewed and compared with the results of this study, the use of FNAB as a decision tool to operate is valid. The decision to operate based on the outcome of hormonal suppression, however, is not valid based on our results.

Clinicopathologic significance of histologic vascular invasion in papillary and follicular thyroid carcinomas.

BACKGROUND: The association of angioinvasion with tumor aggressiveness in follicular and papillary thyroid carcinoma remains unclear. This study addresses this problem focusing on clinicopathologic relevance of angioinvasion in the treatment of papillary thyroid carcinoma and follicular thyroid carcinoma. METHODS: From a university hospital database, 358 patients with papillary thyroid carcinoma or follicular thyroid carcinoma were randomly selected. Their charts were retrospectively analyzed and divided into papillary thyroid carcinoma and follicular thyroid carcinoma groups. Each group was subdivided into angioinvasive and nonangioinvasive tumor subgroups. All data were analyzed using Student's t-test, Mann-Whitney rank sum test, chi-square test, and Fisher's exact test. RESULTS: There were 289 women and 69 men, ages 18 to 89 years. Papillary thyroid carcinoma (86%) was more frequent than follicular thyroid carcinoma. Most patients had nonangioinvasive tumor (90.2%). After a mean followup of 43.6 months, there were no significant differences between papillary thyroid carcinoma subgroups for local recurrence (p = 0.69), persistent elevated serum thyroglobulin (p = 0.568), and distant metastasis rates (p = 0.422). No death related to the cancer was observed in both papillary thyroid carcinoma subgroups (p = 1), except for one death resulting from a concomitant nasopharyngeal cancer. The longterm prognosis was less favorable for angioinvasive papillary thyroid carcinoma based on AJCC (American Joint Committee on Cancer staging), AMES (age, distant metastasis, tumor extent, and size), and MACIS (distant metastasis, age, completeness of primary tumor resection, local invasion, and tumor size), but the angioinvasive papillary thyroid carcinoma were larger than nonangioinvasive papillary thyroid carcinomas. The short-term clinical outcomes in both follicular thyroid carcinoma, after a mean followup of 72.3 months, were comparable in terms of local recurrence (p = 0.34), persistent elevated serum thyroglobulin (p = 1), and distant metastasis (p = 0.597). There was no death related to cancer in both follicular thyroid carcinoma subgroups (p = 1). There were no significant differences between both follicular thyroid carcinoma subgroups for longterm prognosis. CONCLUSIONS: Our results indicate that angioinvasion does not adversely influence short-term outcomes or longterm prognosis in follicular thyroid carcinoma and short-term outcomes in papillary thyroid carcinoma. Angioinvasion is a postoperative pathologic finding that does not justify an ominous prognosis or drastic therapeutic measures.

Prognostic relevance of previous exposure to ionizing radiation in well-differentiated thyroid cancer.

BACKGROUND AND AIMS: Although exposure to ionizing radiation is a well-known risk factor for well-differentiated thyroid cancer, its effects on tumor behavior remain unclear. This study was undertaken to address this question. MATERIALS AND METHODS: We randomly selected 426 patients who underwent thyroidectomy for cancer between 1964 and 2000 and divided them into two groups: previously exposed (ExR); not exposed to radiation (nExR). Data were retrospectively collected. RESULTS: There were 340 female patients and 86 male, age 9-89 years with mean follow-up of 56 months. The ExR group (n=68) was smaller than the nExR group (n=358). Most patients in the ExR group (64.5%) had previously received therapeutic radiation, whereas 25% were occupationally exposed and 10.5% were at risk from environmental radiation. Both groups were similar with regard to extent of thyroidectomy and adjuvant treatment, but neck dissections were more frequent in the nExR group. There were no significant differences between both groups for age, gender, tumor multicentricity, frequency of microcarcinoma, histology, lymph node disease, distant metastasis, and local recurrence. Incidental microcarcinomas were more frequent in the ExR (35.3%) group than in the nExR group (22.1%). Mean tumor size in the ExR group (18.7 mm) was smaller than in the nExR group (22.3 mm). CONCLUSION: Ionizing radiation increases risk for well-differentiated thyroid cancer (WDTC) but not adverse cancer behavior. Surgeons should be aware of the high incidence of microcancer among patients with previous exposure to radiation.

Hürthle cell tumors: using molecular techniques to define a novel classification system.

BACKGROUND: Since ret/PTC gene rearrangements are specific to papillary thyroid carcinoma (PTC), the diagnosis of Hürthle cell PTC (HCPTC) has recently been expanded to include a subset of Hürthle cell tumors (HCTs) that may lack both papillary architecture and/or classic nuclear features but that harbor a ret/PTC gene rearrangement. We hypothesize that such HCPTCs behave in a fashion analogous to other papillary carcinomas, while Hürthle cell carcinomas (HCCs) behave similarly to follicular carcinomas. EDUCATIONAL OBJECTIVES: At the conclusion of this article, participants should be able to discuss HCTs and to identify HCPTCS using molecular techniques. METHODS: A retrospective chart review was carried out on 56 patients with HCTs. All pathological specimens were analyzed for ret/PTC gene rearrangements. Hürthle cell adenoma (HCA) was defined as an HCT that did not exhibit capsular and/or vascular invasion and that lacked a ret/PTC gene rearrangement when evaluated by immunohistochemical and reverse transcription polymerase chain reaction analysis. An HCC was defined as an HCT with capsular and/or vascular invasion that lacked a ret/PTC gene rearrangement, and an HCPTC was defined as any HCT that harbored a ret/PTC gene rearrangement. RESULTS: The subclassification of the 56 HCTs was as follows: 21 HCAs, 15 HCCs, and 20 HCPTCs. No patients with HCA or HCC were ret/PTC positive. Five of the 6 patients with definite lymph node metastasis were in the HCPTC group, demonstrating that molecular analysis helps to explain biological behavior. CONCLUSIONS: Hürthle cell neoplasms can now be classified using histopathological as well as molecular criteria. It appears that the new subclassification of malignant HCTs into follicular (HCC) and papillary (HCPTC) variants identifies 2 distinct biological groups.

Parotid gland tumours in 255 consecutive patients: Mount Sinai Hospital's quality assurance review.

Parotid neoplasms represent a diverse group of tumours found in the head and neck. Complications following parotidectomy, including Frey's syndrome, facial nerve paralysis, sialoceles, and parotid fistulae, have been well documented. A retrospective review of 255 patients treated surgically for parotid masses over an 8-year period at Mount Sinai Hospital in Toronto was reviewed as part of a quality assurance program. The sensitivity, specificity, and predictive values for fine-needle aspiration cytology were analyzed. The incidence of benign and malignant lesions is presented. The complications following parotidectomy are reviewed and in our series are consistent with the figures published in the literature.

Immunohistochemical Localization of p53 in Human Thyroid Neoplasms: Correlation with Biological Behavior.

Molecular analyses of thyroid tumors have documented mutations in the tumor suppressor p53 gene almost exclusively in anaplastic carcinomas. In contrast, immunohistochemistry has localized p53 in differentiated papillary and follicular thyroid cancers. To establish the significance of p53 immunolocalization in these lesions, 78 thyroid tumors of follicular derivation were examined. All tumors were classified by strict criteria and the extent of tumor was determined morphologically. Immunohistochemical staining for p53 was performed on paraffin sections of formalin-fixed tumor tissue. The results of staining were correlated with diagnosis, tumor extent and clinical outcome. Immunopositivity for p53 was diffuse and strong in all five anaplastic carcinomas examined. There was no staining in five of six follicular adenomas. Four of nine follicular carcinomas had some degree of nuclear staining, but this was focal; all nine tumors were confined to the thyroid at the time of examination. Of 49 papillary carcinomas, 26 were intrathyroidal, and 7 of these were occult; there was no p53 positivity in any occult lesion and only S of the 19 palpable lesions stained. In contrast, among 23 papillary carcinomas with extra thyroidal extension or metastases, only 9 were negative for p53 immunoreactivity. Five of seven tall cell papillary carcinomas and one of two insular carcinomas had p53 immunopositivity and this correlated with aggressive behavior. These results support the tumorigenic role of p53 mutations postulated for anaplastic thyroid carcinomas and indicate that localization of p53 by immunohistochemistry is a useful prognostic index of clinical behavior in differentiated thyroid carcinomas of follicular cell derivation.