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Conventional PTC (conventional + ptc)
Selected AbstractsDifferent structural components of conventional papillary thyroid carcinoma display mostly identical BRAF statusINTERNATIONAL JOURNAL OF CANCER, Issue 1 2007Alexander Abrosimov Abstract Activating BRAFT1799A mutation is closely associated with a papillary thyroid carcinoma (PTC) histotype. The transversion is frequently detected in the conventional type, Warthin-like and tall cell variants, but is rare in the follicular variant of PTC. Conventional PTC is often presented with tumors of mixed architecture, which besides the papillary structures also contain areas with follicular and solid morphology in which the details of BRAF mutational status are unknown. We set out to differentially investigate the presence of mutated BRAF in the individual structural components microdissected from 44 formalin-fixed, paraffin-embedded PTC tissues from 40 patients. The mutation was detected in at least 1 structural component in 23 tumors (52%). Different structural components of the same tumor had identical BRAF status in 41/44 tumors (93%). In 3 tumors the BRAFT1799A mutation was found only in the papillary, but not in the follicular component. Mutational patterns identical to those in the primary tumors were found in 11/12 lymph node metastases (92%, including both BRAFT1799A -positive and -negative cases). The high concordance of the BRAF mutational status in structurally distinct areas suggests a rather homogeneous distribution of neoplastic epithelial cells in a conventional PTC tumor in most cases. These results imply the reliability of preoperative molecular diagnosis of PTC regardless of the type of tumor component at the site of biopsy sampling and suggest that the majority of patients with BRAF mutation-positive PTC may benefit from the targeted pharmacotherapy. © 2006 Wiley-Liss, Inc. [source] Immunohistochemical characteristics of diffuse sclerosing variant of papillary carcinoma: comparison with conventional papillary carcinomaAPMIS, Issue 10 2010JA SEUNG KOO Koo JS, Shin E, Hong SW. Immunohistochemical characteristics of diffuse sclerosing variant of papillary carcinoma: comparison with conventional papillary carcinoma. APMIS 2010; 118: 744,52. Diffuse sclerosing variant of papillary carcinoma (DSVPC) is a rare variant of papillary thyroid carcinoma (PTC). It shows different clinicopathologic features to the conventional PTC, but the immunohistochemical characteristics of DSVPC are yet to be more clearly defined. The purpose of this study was to investigate the immunohistochemical features of DSVPC, which are different from those of PTC. Tissue microarray was constructed from the paraffin-embedded tissue of 49 DSVPC and 50 conventional PTC samples. Immunohistochemical stains for p63, p53, galectin-3, cytokeratin 19, ,-catenin, Bcl-2, EMA, E-cadherin, CD15, and CD56 were performed on each tissue microarray. Immunohistochemical stain for p63 was negative in all conventional PTCs, but 14 (28.6%) cases of DSVPC showed p63 expression (p = 0.000). p53 was expressed in 38 (76.0%) cases of conventional PTC and 21 (42.9%) cases of DSVPC (p = 0.001). Galectin-3 was expressed in all 50 cases of conventional PTC, but eight (16.3%) cases of DSVPC did not express galectin-3 (p = 0.003). EMA was expressed more in DSVPC (40.8%) than in conventional PTC (20.0%, p = 0.024). In univariate analyses, Bcl-2 positivity (p = 0.016) and EMA negativity (p = 0.036) in DSVPC were associated with shorter time interval to tumor recurrence, but there was no significance for the two in multivariate analyses. DSVPC, a rare variant of PTC, has different immunohistochemical features from the conventional PTC, showing higher expression rate of p63 and lower expression rate of p53. It also shows galectin-3 negativity and EMA positivity. [source] Papillary microcarcinoma of the thyroid,Prognostic significance of lymph node metastasis and multifocalityCANCER, Issue 1 2003Sin-Ming Chow M.B.B.S Abstract BACKGROUND It is known that patients with papillary microcarcinoma (PMC) of the thyroid gland have a very favorable prognosis. The rising incidence of PMC among papillary thyroid carcinoma (PTC) necessitates the identification of prognostic factors and the formulation of treatment protocols. METHODS The authors conducted a retrospective analysis of 203 patients with PMC who were diagnosed on or before 1999 and were treated at the Department of Clinical Oncology, Queen Elizabeth Hospital, Hong Kong. RESULTS The cause specific survival, locoregional (LR) failure free survival, and distant metastases failure free survival rates at 10 years were 100%, 92.1%, and 97.1%, respectively. Five patients had lung metastases; 2 patients died of their metastases 12.9 years and 14.8 years after diagnosis, and 3 patients achieved clinical remission after radioiodine (RAI) treatment. Twelve patients had LR recurrences. Patients with LR recurrence were highly salvageable with a combination of surgery, RAI treatment, and external radiotherapy; all but one (who refused treatment) were alive without disease at last follow-up. Multivariate analyses did not reveal any independent prognostic factor for survival. The risk of cervical lymph node (LN) recurrence increased 6.2-fold (P = 0.01) and 5.6-fold (P = 0.02) when LN metastases and multifocal disease were present at diagnosis. RAI ablation reduced the LN recurrence rate to 0.27 (P = 0.04). The presence of LN metastasis increased the rate of distant metastasis 11.2-fold (P = 0.03). Age was not a significant factor in predicting disease recurrence or survival. Subdivision by tumor sizes , 5 mm and > 5 mm did not affect the outcome, but no patient with tumors , 5 mm had mortality related to PMC. CONCLUSIONS Despite the overall excellent prognosis for patients with PMC, PMC was associated with a 1.0% disease-related mortality rate, a 5.0% LN recurrence rate, and a 2.5% distant metastasis rate. Therefore, the treatment of patients with PMC should be no different from the treatment of patients with conventional PTC: i.e., complete surgery with consideration for RAI and/or external radiation therapy if poor prognostic factors are present. Cancer 2003;98:31,40. © 2003 American Cancer Society. DOI 10.1002/cncr.11442 [source] BRAF mutations in an Italian cohort of thyroid cancersCLINICAL ENDOCRINOLOGY, Issue 2 2004Laura Fugazzola Summary objective, Recently, a somatic point mutation of the BRAF gene (V599E) has been identified as the most common genetic event in papillary thyroid carcinoma (PTC) with a variable frequency (about 25,70%) in different series from USA, Japan, Portugal and Ukraine. design, In the present study, the genetic analysis of BRAF in an Italian cohort of 65 thyroid tumours with corresponding normal tissues and 21 thyroid benign disorders is reported. methods, For BRAF analysis, the somatic DNA was PCR amplified by means of specific intronic primers and PCR products were directly sequenced. Statistical analyses were obtained by means of Fisher's exact test. results, All mutations detected involved a T > A transversion at 1796 (V599E) and were heterozygous. Overall, BRAFV599E mutation was found in 18/56 (32·1%) PTCs. According to the histological type of the tumour, the mutation was present in 38·3% of cases of conventional PTC (18/47), in 0/6 follicular variant of PTC, in 0/3 oncocytic variant of PTC. No BRAF mutations were detected either in five follicular carcinomas, or in four poorly differentiated or undifferentiated cancers or in benign thyroid disorders. No statistically significant correlation of BRAF mutation with patient age and gender, with multicentricity of the tumour, with the lymphocytic infiltration of the tissue, with the stage and with the recurrence rate, was found. BRAFV599E tended to be associated, although not significantly, with a greater volume and extension of the tumour and with lymph-nodal metastases at surgery. conclusions, In conclusion, the present study on the first Italian series of thyroid cancers shows a frequency of 38·3% of BRAFV599E in the classical variant of PTC, confirming the key role of this mutation in promoting tumourigenesis. [source] | ||||||||||