The frequency and prognostic significance of the histologic type in early-stage ovarian cancer (OC) is not as well established as in advanced stages. In addition, histologic typing based only on morphologic features may be difficult, especially in high-grade tumors. In this study, we have analyzed a prospective cohort of 502 early-stage OCs to investigate their frequency, immunohistochemical characteristics, and survival of the 5 main histologic types. Histotype was assigned according to not only the morphologic features but also according to the expression pattern of WT1, p53, Napsin A, and progesterone receptors. In addition, an extended panel including p16, β-catenin, HER2, Arid1A, HINF1B, CK7, CDX2, and CK20 was used to refine the diagnosis in difficult cases. In this series, the frequency of the 5 major histologic types was as follows: endometrioid carcinoma, 32.7%; clear cell carcinoma, 25.1%; high-grade serous carcinoma (HGSC), 24.7%; mucinous carcinoma, 10.2%; low-grade serous carcinoma, 4.6%; and others, 2.8%. The combination of morphology and immunohistochemistry allowed the reclassification of 23% of OCs. The lowest concordance was found between samples initially diagnosed as endometrioid, but finally classified as high-grade serous tumors (22% error rate). Endometrioid carcinoma was the most favorable histologic type, whereas HGSC and low-grade serous carcinoma had the worst prognosis. Clear cell carcinoma with abnormal p53 immunostaining pattern also had poor prognosis. Although histologic grade was not a prognostic factor among early-stage endometrioid OCs, distinction between grade 3 endometrioid OC and HGSC is recommended, taking into account differences in prognosis and molecular alterations that can guide different treatments.

This is, to our knowledge, the first documented report of erythrophagocytic tumour cells in human melanomas and primary carcinomas. Biological considerations apart, this unusual feature can prove to be of value to avoid a misdiagnosis of a variety of haematopoietic malignancies.

Endometrial Cancer (EC) is one of the most common malignancies in women in developed countries. Molecular characterization of different biotypes may improve clinical management of EC. The Cancer Genome Atlas (TCGA) project has revealed four prognostic EC subgroups: POLE, MSI; Copy Number Low (CNL) and Copy Number High (CNH). The goal of this study was to develop a method to classify tumors in any of the four EC prognostic groups using affordable molecular techniques. Ninety-six Formalin-Fixed Paraffin-embedded (FFPE) samples were sequenced following a NGS TruSeq Custom Amplicon low input (Illumina) protocol interrogating a multi-gene panel. MSI analysis was performed by fragment analysis using eight specific microsatellite markers. A Random Forest classification algorithm (RFA), considering NGS results, was developed to stratify EC patients into different prognostic groups. Our approach correctly classifies the EC patients into the four TCGA prognostic biotypes. The RFA assigned the samples to the CNH and CNL groups with an accuracy of 0.9753 (p < 0.001). The prognostic value of these groups was prospectively reproduced on our series both for Disease-Free Survival (p = 0.004) and Overall Survival (p = 0.030).Hence, with the molecular approach herein described, a precise and suitable tool that mimics the prognostic EC subtypes has been solved and validated. Procedure that might be introduced into routine diagnostic practices.

Primary breast lymphoma is a rare form of extra-nodal lymphoid neoplasm. The most common histological type is the diffuse large B-cell lymphoma, which represents 60–80% of all the cases. Our study analyzes the mutational profile of the primary lymphoma of the breast through targeted massive sequencing with a panel of 38 genes in a group of 17 patients with primary breast diffuse large B-cell lymphoma. Seventy-point-five percent of the patients presented with stage IE and 29.5% with stage IIE. 44% of the cases correspond to lymphomas with germinal center phenotype and 33.3% to activated B-cell. The genes with a higher mutational frequency include PIM1 (in 50% of the analyzed samples), MYD88 (39%), CD79B, PRDM1 and CARD11 (17%), KMT2D, TNFIAP3 and CREBBP (11%). The profile of mutant genes involves mostly the NFκB signaling pathway. The high frequency of mutations in PIM1 compared with other lymphomas may have implications in the clinical presentation and evolution of this type of lymphoma.

Pleomorphic hyalinizing angiectatic tumor (PHAT) is an uncommon soft tissue tumor usually located in extremities or trunk. We report 3 new cases with histopathologic diagnosis of PHAT, one with recurrence and sarcomatous myxofibrosarcoma component and another with unreported soft tissue palpebral location. Clinical data, histopathology, immunohistochemistry, fluorescence in situ hybridization, and follow-up data are described. The histopathology showed a tumor with angiectatic blood vessel proliferation and perivascular hyaline material associated with focal pleomorphic cells. The recurrent tumor revealed a histopathologic pattern corresponding to a myxofibrosarcoma. Vimentin and CD99 were positive in tumor cells and CD34 was strongly positive in the tumor cells from the recurrence. Ki-67 was poor positive but with increased positivity in the recurrence. The positivity of p53 and chromosome 22 polysomy were detected in the recurrence. At present, the 3 patients are free of disease and no metastases have been detected. Indeed, the possibility that PHAT may represent a histopathologic pattern and not a true neoplastic entity with specific genetic alterations cannot be excluded at present, and further studies are required.