Aleš Ryška

Mammary analogue secretory carcinoma of salivary glands, containing the ETV6-NTRK3 fusion gene: a hitherto undescribed salivary gland tumor entity.

We present a series of 16 salivary gland tumors with histomorphologic and immunohistochemical features reminiscent of secretory carcinoma of the breast. This is a hitherto undescribed and distinctive salivary gland neoplasm, with features resembling both salivary acinic cell carcinoma (AciCC) and low-grade cystadenocarcinoma, and displaying strong similarities to breast secretory carcinoma. Microscopically, the tumors have a lobulated growth pattern and are composed of microcystic and glandular spaces with abundant eosinophilic homogenous or bubbly secretory material positive for periodic acid-Schiff, mucicarmine, MUC1, MUC4, and mammaglobin. The neoplasms also show strong vimentin, S-100 protein, and STAT5a positivity. For this tumor, we propose a designation mammary analogue secretory carcinoma of salivary glands (MASC). The 16 patients comprised 9 men and 7 women, with a mean age of 46 years (range 21 to 75). Thirteen cases occurred in the parotid gland, and one each in the minor salivary glands of the buccal mucosa, upper lip, and palate. The mean size of the tumors was 2.1 cm (range 0.7 to 5.5 cm). The duration of symptoms was recorded in 11 cases and ranged from 2 months to 30 years. Clinical follow-up was available in 13 cases, and ranged from 3 months to 10 years. Four patients suffered local recurrences. Two patients died, 1 of them owing to multiple local recurrences with extension to the temporal bone, and another owing to metastatic dissemination to cervical lymph nodes, pleura, pericardium, and lungs. We have shown a t(12;15) (p13;q25) ETV6-NTRK3 translocation in all but one case of MASC suitable for analysis. One case was not analyzable and another was not available for testing. This translocation was not found in any conventional salivary AciCC (12 cases), nor in other tumor types including pleomorphic adenoma (1 case) and low-grade cribriform cystadenocarcinoma (1 case), whereas ETV6-NTRK3 gene rearrangements were proven in all 3 tested cases of mammary secretory carcinoma. Thus, our results strongly support the concept that MASC and AciCC are different entities.

Sensitivity and specificity of the fine needle aspiration biopsy of the thyroid: clinical point of view

The rates of sensitivity and specificity of fine needle aspiration biopsy (FNAB) for the diagnosis of thyroid malignancy differ considerably among various reported series. These values are influenced by three factors: (a) whether only clearly positive and negative results are considered, or whether the commonly encountered 10–20% of indeterminate/suspicious ones are included; (b) whether adenomas are considered as neoplasms in one group with carcinomas; and (c) whether only histologically proven cases are used in calculations or whether patients with benign clinical follow‐up are included.

Tumor-Infiltrating Lymphocytes Predict Response to Neoadjuvant Chemotherapy in Patients with Breast Carcinoma

Tumor-infiltrating leukocytes and other immunohistochemical parameters were evaluated in pretherapeutic biopsies and resection specimens in 73 patients undergoing neoadjuvant chemotherapy with doxorubicin and paclitaxel. Ten patients with pathological complete response had significantly higher p53 expression, CD3+ lymphocyte and CD83+ cell counts, and lower progesterone receptor expression. In the remaining 63 patients, a significant decrease in the percentage of Ki-67, vascular endothelial growth factor expression, CD68+ monocytes, and increased CD31+, CD34+, and SMA+ stromal vessels, maximal CD3+ and CD56+ lymphocyte, maximal and mean CD83+ cell, maximal CD1a+, and maximal and mean S100+ cell counts were observed after neoadjuvant chemotherapy.

Somatic mutations in the RET proto-oncogene in sporadic medullary thyroid carcinomas

The frequency and prognostic relevance of RET proto-oncogene somatic mutations in sporadic medullary thyroid carcinoma (MTC) remain controversial. In order to study somatic mutations in the RET proto-oncogene in sporadic MTCs found in the Czech population and to correlate these mutations with clinical and pathological characteristics, we investigated 48 truly sporadic MTCs by sequencing classical risk exons 10, 11, 13, 14, 15 and 16. From the 48 tumors studied, 23 (48%) had somatic mutation in the RET proto-oncogene in exons 10, 11, 15 or 16. The classical somatic mutation Met918Thr in exon 16 was only found in 13 tumors (27%). In five cases, multiple somatic mutations and deletions were detected. A statistically significant correlation between the presence of somatic mutation with more advanced pathological TNM stages was observed. Other clinical and pathological characteristics did not show any statistical significant association with the presence or absence of somatic mutation.

Exon 5 of the RET proto-oncogene: a newly detected risk exon for familial medullary thyroid carcinoma, a novel germ-line mutation Gly321Arg.

Familial medullary thyroid carcinoma (FMTC) is an autosomal dominant inherited disease, characterized by germ-line mutations in the RET proto-oncogene, mainly in exons 10 and 11, but also in exons 13, 14 and 15. Recently, mutations in exons 8 and 16 associated with FMTC were also described. In the herein presented study, single strand conformation polymorphism (SSCP) method for rapid screening of mutations in the RET proto-oncogene and fluorescent sequencing method were used. In one Czech family with FMTC, we have identified a novel missense point mutation of the RET proto-oncogene in exon 5, that results in substitution of arginine by glycine at codon 321 in the cadherin-like domain of ret protein. It seems that this mutation causes FMTC as no other mutation was found in the classical risk exons (10, 11, 13, 14, 15 and 16) of the RET proto-oncogene. The mutation cosegregates with medullary thyroid carcinoma (MTC) or C cell hyperplasia (CCH) in two patients; two other family members are mutation carriers without clinical signs of MTC so far. To improve the diagnosis of FMTC, analysis of exon 5 of the RET proto-oncogene should be considered in families with no identified classical RET mutations.

Oncocytic myoepithelioma and pleomorphic adenoma of the salivary glands.

Abstract Twenty oncocytic myoepitheliomas (MEs) and pleomorphic adenomas (PAs) were composed of interlacing fascicles of swollen spindle-shaped or/and epithelioid oncocytic myoepithelial cells showing intense finely granular immunoreactivity with anti-mitochondrial antibody. Focal vacuolation of the cytoplasm of oncocytic myoepithelial cells and their gradual transition into sebaceous metaplasia were observed in 3 cases. Another unusual feature found in 5 cases was the presence of slit-like adenomatoid spaces lined with double-layered oncocytic myoepithelium closely resembling Warthin’s tumour. The nuclei of oncocytic cells were characterized by enlargement, hyperchromasia and polymorphism, which should not be confused with malignancy. Oncocytic change in myoepithelial cells in MEs and PAs can cause pitfalls in the differential diagnosis of salivary gland tumours. We describe some unusual histological features associated with onococytic metaplasia in benign myoepithelial cell-derived salivary gland tumours, hoping to help to avoid the overdiagnosis of malignancy.

Oncocytic papillary carcinoma with lymphoid stroma (Warthin-like tumour) of the thyroid: a distinct entity with favourable prognosis

Oncocytic papillary carcinoma with lymphoid stroma (Warthin‐like tumour) of the thyroid: a distinct entity with favourable prognosis

Epithelioid haemangiosarcoma of the thyroid gland. Report of six cases from a non‐Alpine region

Aim : To report a series of six cases of thyroid haemangiosarcoma (HAS) from a non‐Alpine region.

Mammary analog secretory carcinoma of salivary glands: a report of 2 cases with expression of basal/myoepithelial markers (calponin, CD10 and p63 protein).

Mammary analog secretory carcinoma (MASC) of salivary glands is a recently described neoplasm with favorable outcome. We describe 2 cases of MASC occurring in a 34-year-old female and a 58-year-old male, both presenting with a swelling of upper lip and right parotid gland, measuring 15 and 20mm, respectively. Without adjuvant treatment, both patients have been free of disease for 15 months and 12 months since the operation. Microscopically, both tumors were cystic and showed tubular and cystopapillary architecture. The tumor cells had round to oval nuclei and eosinophilic cytoplasm. Presence of eosinophilic material was evident within cystic spaces. Immunohistochemically, both tumors expressed cytokeratins (CK), CK7, CK8, CK18, epithelial membrane antigen, vimentin, S-100 protein, mammaglobin, and STAT5a (signal transducer and activator of transcription 5a). Interestingly, both tumors showed variable expression of basal/myoepithelial markers. In one case, we observed diffuse expression of calponin and focal expression of p63 whereas expression of CD10 was absent. In the second case, the staining of calponin was negative, but there was focal expression of both p63 and CD10. Both neoplasms harbored the ETV6-NTRK3 fusion transcript as proved by RT-PCR. Although previously reported only rarely, we conclude that MASC may show expression of basal/myoepithelial markers.

BRAFV600E mutation in the pathogenesis of a large series of papillary thyroid carcinoma in Czech Republic.

Background: Activating point mutation of the BRAF gene, the most common genetic alteration reported in papillary thyroid carcinomas (PTC), has been associated with poor prognostic characteristics. Aim: Our objective was to determine the frequency of BRAFV600E mutation in PTC tumor tissues from the period 1960–2007 and to correlate it with clinicopathological parameters. Subjects and methods: DNAs were extracted from 242 PTCs, 23 sporadic medullary carcinomas, one anaplastic carcinoma and 6 poorly differentiated carcinomas. The presence of BRAFV600E mutation was determined using single strand conformation polymorphism method and verified by direct sequencing. Results: BRAFV600E mutation was detected in 81 of 242 PTCs (33.5%), in one of 6 poorly differentiated carcinomas (16.7%) and in anaplastic carcinoma. BRAFV600E mutation was much less frequent in the follicular variant compared to classical variant and mixed follicular-classical variant of PTCs (p=0.001). BRAFV600E mutation was significantly associated with presence of nodal metastasis (p=0.029), more advanced TNM stage (p=0.014) and recurrence of disease (p=0.008). The mutation correlated with a higher age at diagnosis (p=0.049) and with a greater tumor size (p=0.041). Multivariate analysis confirmed these findings. The prevalence of BRAFV600E mutation before 1986 was significantly lower than after it (p=0.008). Conclusions: Our data suggest that BRAFV600E mutation is associated with high-risk clinicopathological characteristics of PTC and worse prognosis of patients. The frequency of the mutation significantly varied during the observed period but rather because of the different age distribution of patients in particular periods than as a consequence of Chernobyl accident.