Unusual Clinical Presentation of Gastrointestinal Clear Cell Sarcoma.

BACKGROUND: Use of molecular assays is gradually becoming a mandatory part of the clinical management of soft tissue tumors, however the choice and the interpretation of these tests may present a challenge. SUMMARY: This report demonstrates an unusual presentation of sarcoma, which was initially diagnosed as a tumor of unknown primary site. Given the presence of vimentin, Fli-1, CD99 and S100 markers, lack of immunostaining for melan A, HMB45, MITF, synaptophysin, CD56, myf4, CKAE1/3 and WT-1, as well as the presence of EWSR1 translocation determined by a break-apart FISH assay, Ewing's sarcoma (ES) diagnosis seemed to be well justified. However, polymerase chain reaction testing for ES-specific rearrangements (EWSR1/FLI1, EWSR1/ERG, EWSR1/ETV1, EWSR1/ETV4, EWS/FEV) failed to confirm the ES origin of the neoplastic tissue. We further considered clinical, morphological, immunohistochemical and molecular diagnostic features of other types of EWSR1-rearranged sarcomas and performed molecular testing for gastrointestinal clear cell sarcoma. The polymerase chain reaction assay revealed EWSR1ex7/ATF1ex5 fusion, thus confirming the latter diagnosis. Subsequent high-precision computed tomography of the abdominal cavity revealed a 5-cm tumor of the small bowel, which was subjected to surgical resection. KEY MESSAGE: This report exemplifies that the use of anonymous cytogenetic assays, such as break-apart FISH EWSR1 testing, may not be sufficient even in case of a perfect match with relevant morphological and immunohistochemical tumor features. PRACTICAL IMPLICATIONS: Explicit identification of the translocation gene partners is indeed important for proper sarcoma diagnosis management.

Novel ALK fusion partners in lung cancer.

Detection of ALK rearrangements in patients with non-small cell lung cancer (NSCLC) presents a significant technical challenge due to the existence of multiple translocation partners and break-points. To improve the performance of PCR-based tests, we utilized the combination of 2 assays, i.e. the variant-specific PCR for the 5 most common ALK rearrangements and the test for unbalanced 5'/3'-end ALK expression. Overall, convincing evidence for the presence of ALK translocation was obtained for 34/400 (8.5%) cases, including 14 EML4ex13/ALKex20, 12 EML4ex6/ALKex20, 3 EML4ex18/ALKex20, 2 EML4ex20/ALKex20 variants and 3 tumors with novel translocation partners. 386 (96.5%) out of 400 EGFR mutation-negative NSCLCs were concordant for both tests, being either positive (n = 26) or negative (n = 360) for ALK translocation; 49 of these samples (6 ALK+, 43 ALK-) were further evaluated by FISH, and there were no instances of disagreement. Among the 14 (3.5%) "discordant" tumors, 5 demonstrated ALK translocation by the first but not by the second PCR assay, and 9 had unbalanced ALK expression in the absence of known ALK fusion variants. 5 samples from the latter group were subjected to FISH, and the presence of translocation was confirmed in 2 cases. Next generation sequencing analysis of these 2 samples identified novel translocation partners, DCTN1 and SQSTM1; furthermore, the DCTN1/ALK fusion was also found in another NSCLC sample with unbalanced 5'/3'-end ALK expression, indicating a recurrent nature of this translocation. We conclude that the combination of 2 different PCR tests is a viable approach for the diagnostics of ALK rearrangements. Systematic typing of ALK fusions is likely to reveal new NSCLC-specific ALK partners.

Invasion and genome reproduction of the trophoblast cells of placenta junctional zone in the field vole, Microtus rossiaemeridionalis.

In the field vole Microtus rossiaemeridionalis, like in other rodents, invasive secondary giant trophoblast cells (SGTC) form a continuous layer at the foeto-maternal interface in the beginning of placentation. However, in the field vole, at midgestation, clusters of junctional zone (JZ) trophoblast non-giant cells interrupt SGTC layer and progressively replace SGTC at the border of decidua basalis. As a result, 'border' cells form a continuous stratum of cytokeratin-positive glycogen-rich cells at the foeto-maternal interface. SGTC plunge into JZ and line the lacunae with maternal blood. SGTC are bound by their highly cytokeratin-positive sprouts forming a framework that holds other trophoblast cell populations. According to DNA cytophotometry, the 'border' cells show the highest ploidy among the JZ cells (up to 46% of 8c cells). Thus, in M. rossiaemeridionalis the role of barrier between semiallogenic foetal and maternal tissues is shifted from the highly endopolyploid (32c-1024c) SGTC to the specific subpopulation of glycogen-rich non-giant (2c-16c) 'border' trophoblast cells that, however, exceed the ploidy of the deeply located and/or proliferative JZ trophoblast cells.

Aromatase, CYP1B1 and fatty acid synthase expression in breast tumors of BRCA1 mutation carriers.

Numerous experimental evidence suggest that BRCA1-associated breast carcinomas may have distinct endocrine and metabolic features, however these peculiarities are poorly evaluated in clinical settings. Here we comparatively analyzed for the first time aromatase, estrogen 4-hydroxylase (CYP1B1) and fatty acid synthase immunohistochemical expression in breast tumors obtained from 12 BRCA1 mutations carriers and 22 non-carriers. Aromatase expression was higher in mutation carriers than in sporadic cases (p = 0.04), which confirms the earlier results obtained in cell lines with down-regulated wild-type BRCA1 and corroborates the usage of aromatase inhibitors in such patients. No differences between study groups were found in the expression of CYP1B1 and fatty acid synthase, which does not, however, mitigate the need of further search for manifestations of the excessive genotoxic effects of estrogens and for increased lipogenesis in BRCA1 mutations carriers.

Signs of proinflammatory/genotoxic switch (adipogenotoxicosis) in mammary fat of breast cancer patients: role of menopausal status, estrogens and hyperglycemia.

The abundance of fat tissue surrounding normal and malignant epithelial mammary cells raises the questions whether such "adipose milieu" is important in the local proinflammatory/genotoxic shift, which apparently promotes tumor development and worsens prognosis, and what conditions stimulate this shift, or "adipogenotoxicosis." We studied 95 mammary fat samples from 70 postmenopausal and 25 premenopausal breast cancer (BC) patients at a distance of 1.5-2.0 cm from tumors. The levels of leptin, adiponectin, TNFalpha and IL-6 release after 4-hr incubation of the samples were evaluated with ELISA, nitric oxide (NO) production by Griess reaction and lipid peroxidation by determination of thiobarbiturate-reactive products (TBRP). Infiltration of fat with macrophages (CD68-positive cells) and expression of cytochrome P450 1B1/estrogen 4-hydroxylase (CYP1B1) were detected by immunohistochemistry. Aromatase (CYP19) activity in mammary fat was measured by (3)H(2)O release from (3)H-1beta-androstenedione. In the postmenopausal BC patients, NO and TNFalpha production by adipose tissue explants increased independent of BMI and in parallel with decreasing leptin and, especially, adiponectin release. In the premenopausal patients, higher CYP1B1 expression and TBRP level were found in mammary fat, while higher aromatase activity was combined with higher CYP1B1 expression as well as NO and IL-6 production. In the postmenopausal group, impaired glucose tolerance was associated with higher IL-6 release production by fat and with higher IL-6/adiponectin ratio. Thus, signs of adipogenotoxicosis in mammary fat can be found in both pre- and postmenopausal BC patients. This condition is likely being maintained through estrogen- and glucose-related factors and mechanisms presumably associated with less favorable types of hormonal carcinogenesis.