Mast cell neoplasm: a challenging pathological diagnosis.

Systemic mastocytosis (SM) is a myeloid neoplasm characterized by abnormal growth and accumulation of neoplastic mast cells in at least one extracutaneous site. Clinical presentation and course are variable, most patients are developing an indolent disease and some, an aggressive/leukemic form. Because of its rarity, most physicians are unfamiliar with this disease and do not readily diagnose it. In the present retrospective study, the authors describe 12 patients diagnosed with mast cell neoplasm. Cases were selected from three institutions from Campinas and São Paulo City, Brazil. Morphological features and diagnostic pitfalls are emphasized. Patients' age ranged from 15 to 81 years (mean 51.6 years). Male and female were affected similarly (1:1). Ten patients were classified as aggressive SM, one patient as SM with an associated acute promyelocytic leukemia with t(15;17), and one patient with mast cell sarcoma. The most common clinical findings included anemia (9 patients), thrombocytopenia (3 patients), and skin lesions (3 patients). Bone marrow was involved in 11 patients at diagnosis, followed by skin (5 patients). Five morphological patterns were present: mast cell aggregates (5), plasmacytoid (4), monocytoid (2), spindle cell (2), and epithelioid/pleomorphic (1); two patients showed two histological patterns. In all cases, neoplastic cells were positive for CD117/C-KIT. C-KIT D816V mutation was present in four patients, C-KIT K509I in two, and del(7q22) in one; in five cases no mutational status was available. Despite limited resources, basically morphology and a restricted immunohistochemical panel, it is possible to diagnose mast cell neoplasm. Of note, the pathologist should recognize the different morphological variants of the disease and include adequate markers when requesting immunohistochemical studies.

Study on collagen parameters in vulvar cancer and preneoplastic lesions by Second Harmonic Generation microscopy.

The extracellular matrix plays an important role in cellular balance, and collagen fibers are its most important component. Over the last few years, second harmonic generation (SHG) microscopy has been used for the analysis of collagen fibers in several types of gynaecological cancers, such as breast and ovarian cancer. The value of collagen parameters obtained with this technique to gain insights on the physiopathology and on the prognostic evaluation of cancer has been advocated. Herein, we have characterized the collagen fibers in squamous cell carcinoma (VSCC) and preneoplastic lesions using the SHG microscopy. Collagen parameters, quantity, organization, and uniformity, of VSCC, adjacent skin of VSCC or preneoplastic lesions were compared with values obtained in normal tissue of healthy control. There was an evident decrease in the values of collagen fiber parameters in the VSCC. Increased quantity and uniformity of tumor associated collagen fibers were associated with the presence of lymph node metastases, which suggest a prognostic value of such parameters in the evaluation of vulvar cancer.

Exploring Collagen Parameters in Pure Special Types of Invasive Breast Cancer.

One of the promising tools to evaluate collagen in the extracellular matrix is the second-harmonic generation microscopy (SHG). This approach may shed light on the biological behavior of cancers and their taxonomy, but has not yet been applied to characterize collagen fibers in cases diagnosed as invasive breast carcinoma (BC) of histological special types (IBC-ST). Tissue sections from 99 patients with IBC-ST and 21 of invasive breast carcinoma of no special type (IBC-NST) were submitted to evaluation of collagen parameters by SHG. Tissue microarray was performed to evaluate immunohistochemical-based molecular subtype. In intratumoral areas, fSHG and bSHG (forward-SHG and backward-SHG) collagen parameters achieved their lowest values in mucinous, papillary and medullary carcinomas, whereas the highest values were found in classic invasive lobular and tubular carcinomas. Unsupervised hierarchical cluster analysis and minimal spanning tree using intratumoral collagen parameters allowed the identification of three main groups of breast cancer: group A (classic invasive lobular and tubular carcinomas); group B (IBC-NST, metaplastic, invasive apocrine and micropapillary carcinomas); and group C (medullary, mucinous and papillary carcinomas). Our findings provide further characterization of the tumor microenvironment of IBC-ST. This understanding may add information to build more consistent tumor categorization and to refine prognostication.

Role of discoidin domain receptor 2 (DDR2) and microRNA-182 in survival of women with high-grade serous ovarian cancer.

The objective of this study is to evaluate the relationship between discoidin domain receptor 2 (DDR2) and miR-182 expression with response to platinum-based chemotherapy and survival in women with high-grade serous ovarian cancer (HGSOC). We evaluated 78 women with HGSOC stages I-IV, diagnosed between 1996 and 2013, and followed up until 2016. DDR2 expression was assessed using immunohistochemistry on tissue microarray slides. The microRNAs were evaluated by qRT-PCR. DDR2 expression was high in 11 (14.1%) women. PFS was significantly lower in women with FIGO stage I/II - versus III/IV, post-surgery residual disease and high expression of DDR2. Women with postsurgery residual disease, FIGO stage I/II - versus III/IV and DDR2 expression had worse OS, but only post-surgery residual disease remained an independent prognostic factor for worse OS in multivariable analysis. miR-182 expression levels were significantly lower in patients harboring tumors with higher expression of DDR2 (p < 0.001). In this relatively large cohort of women with HSGOC, higher DDR2 expression was associated with lower miR-182 levels and worse PFS, suggesting that these molecules may be associated with mechanisms of HGSOC progression.

BRCA1, Ki67, and ß-Catenin Immunoexpression Is Not Related to Differentiation, Platinum Response, or Prognosis in Women With Low- and High-Grade Serous Ovarian Carcinoma.

OBJECTIVE: The purpose of this study was to compare the immunohistochemical expression of BRCA1, Ki67, and ß-catenin in women with low-grade (LGSOC) and high-grade serous ovarian carcinomas (HGSOC) and their relationship with clinicopathological features, response to platinum-based chemotherapy, and survival. METHODS: For this study, 21 LGSOC and 85 HGSOC stage I to IV cases, diagnosed and treated from 1996 to 2013 and followed-up until December 2016, were included. BRCA1, Ki67, and ß-catenin expression was assessed using tissue microarray-based immunohistochemistry. RESULTS: Women with HGSOC were significantly more likely to have advanced-stage disease (P < 0.001), higher CA125 levels (P < 0.001), postsurgery residual disease (P < 0.01), and higher rates of disease progression and recurrence (P = 0.001). The percentage of women with HGSOC whose tumors expressed Ki67 was significantly higher compared with women with LGSOC (P < 0.001). The expression of BRCA1 and ß-catenin did not differ between LGSOC and HGSOC (P = 0.12 and P = 1.00, respectively). The clinicopathological features and the response to platinum-based chemotherapy did not differ according to the BRCA1, Ki67, and ß-catenin expression in either group. In HGSOC, only International Federation of Gynecology and Obstetrics stage was independently associated with poor survival (PFS and OS). CONCLUSIONS: Ki67 expression was significantly higher in HGSOC. BRCA1 and ß-catenin expression did not differ between LGSOC and HGSOC samples. BRCA1, Ki67, and ß-catenin expression was neither related to clinicopathological features, response to platinum-based chemotherapy, nor survival. Only International Federation of Gynecology and Obstetrics stage remained associated with poor survival in women with HGSOC.