Vulvar leiomyosarcoma: A case report.

Vulvar leiomyosarcoma is a rare malignant smooth muscle tumor and the most common type of vulvar sarcoma. It can mimic benign tumors, and misdiagnosis may delay appropriate treatment. A 35-year-old woman presented to the outpatient gynecology clinic at the Mirebalais Teaching Hospital for a right vulvar mass. A complete excision of the mass was performed. Histopathology with immunohistochemistry demonstrated leiomyosarcoma. We describe the contextual challenges that ultimately compromised her care, highlighting the challenges to safe delivery of cancer care in our setting.

STK11 Adnexal Tumor in an Adolescent Female: Diagnostic Pitfalls of a Recently Described Entity.

STK11 adnexal tumor is a recently described entity with less than 25 cases reported to date. These aggressive tumors typically occur in paratubal/paraovarian soft tissues, have characteristically striking morphologic and immunohistochemical heterogeneity, and harbor pathognomonic alterations in STK11. These occur almost exclusively in adult patients, with only one reported in a pediatric patient (to our knowledge). A previously healthy 16-year-old female presented with acute abdominal pain. Imaging studies revealed large bilateral solid and cystic adnexal masses, ascites, and peritoneal nodules. Following frozen section evaluation of a left ovarian surface nodule, bilateral salpingo-oophorectomy and tumor debulking were performed. Histologically, the tumor demonstrated distinctively variable cytoarchitecture, myxoid stroma, and mixed immunophenotype. A next generation sequencing-based assay identified a pathogenic STK11 mutation. We report the youngest patient to date with an STK11 adnexal tumor, highlighting key clinicopathologic and molecular features in order to contrast them with those of other pediatric intra-abdominal malignancies. This rare and unfamiliar tumor poses a considerable diagnostic challenge and requires a multidisciplinary integrated approach to diagnosis.

Molecular changes in endometriosis-associated ovarian clear cell carcinoma.

BACKGROUND: Endometriosis is frequently associated with and thought of having propensity to develop into ovarian clear cell carcinoma (OCCC), although the molecular transformation mechanism is not completely understood. METHODS: We employed immunohistochemical (IHC) staining for marker expression along the potential progression continuum. Expression profiling of microdissected endometriotic and OCCC cells from patient-matched formalin-fixed, paraffin-embedded samples was performed to explore the carcinogenic pathways. Function of novel biomarkers was confirmed by knockdown experiments. RESULTS: PTEN was significantly lost in both endometriosis and invasive tumour tissues, while oestrogen receptor (ER) expression was lost in OCCC relative to endometriosis. XRCC5, PTCH2, eEF1A2 and PPP1R14B were significantly overexpressed in OCCC and associated endometriosis, but not in benign endometriosis (p ⩽ 0.004). Knockdown experiments with XRCC5 and PTCH2 in a clear cell cancer cell line resulted in significant growth inhibition. There was also significant silencing of a panel of target genes with histone H3 lysine 27 trimethylation, a signature of polycomb chromatin-remodelling complex in OCCC. IHC confirmed the loss of expression of one such polycomb target gene, the serous ovarian cancer lineage marker Wilms' tumour protein 1 (WT1) in OCCC, while endometriotic tissues showed significant co-expression of WT1 and ER. CONCLUSIONS: Loss of PTEN expression is proposed as an early and permissive event in endometriosis development, while the loss of ER and polycomb-mediated transcriptional reprogramming for pluripotency may play an important role in the ultimate transformation process. Our study provides new evidence to redefine the pathogenic programme for lineage-specific transformation of endometriosis to OCCC.

Targeted development of specific biomarkers of endometrial stromal cell differentiation using bioinformatics: the IFITM1 model.

When classifying cellular uterine mesenchymal neoplasms, histological distinction of endometrial stromal from smooth muscle neoplasms can be difficult. The only widely established marker of endometrial stromal differentiation, CD10, has marginal specificity. We took a bioinformatics approach to identify more specific markers of endometrial stromal differentiation by searching the Human Protein Atlas, a public database of protein expression profiles. After screening the database using different methods, interferon-induced transmembrane protein 1 (IFITM1) was selected for further analysis. Immunohistochemistry for IFITM1 was performed using tissue sections from the selected cases of proliferative endometrium (22), secretory endometrium (6), inactive endometrium (19), adenomyosis (10), conventional leiomyoma (11), cellular leiomyoma (16), endometrial stromal nodule (2), low-grade endometrial stromal sarcoma (16), high-grade endometrial stromal sarcoma (2) and undifferentiated uterine sarcoma (2). Stained slides were scored in terms of intensity and distribution. Normal endometrial samples uniformly showed diffuse and strong IFITM1 staining. Endometrial stromal neoplasms, particularly low-grade endometrial stromal sarcoma, showed higher IFITM1 expression compared with smooth muscle neoplasms (P<0.0001). IFITM1 immunohistochemistry has high sensitivity and specificity, particularly in the distinction between low-grade endometrial stromal sarcoma and leiomyoma (81.2 and 86.7%, respectively). Our results indicate that IFITM1 is a sensitive and specific marker of endometrial stromal differentiation across the spectrum from proliferative endometrium to metastatic stromal sarcoma. IFITM1 is a potential valuable addition to immunohistochemical panels used in the diagnosis of cellular mesenchymal uterine tumors. Further studies with larger number of cases are necessary to corroborate this impression and determine the utility of IFITM1 in routine practice. This study is a clear example of how bioinformatics, particularly tools for mining genomic and proteomic databases, can enhance and accelerate biomarker development in diagnostic pathology.

Endometrial intraepithelial neoplasia with secretory differentiation: diagnostic features and underlying mechanisms.

Endometrial intraepithelial neoplasia (EIN) with secretory differentiation and ordinary EIN occurring in a secretory context are rare but recognized findings. We determined how often secretory differentiation in EIN was associated with evidence of circulating progestins in the background endometrium, and studied clinical characteristics and clinical outcomes of affected patients. We selected 41 patients with secretory differentiation in either the EIN itself (n=31) and/or background endometrium (n=38). Most (90%, 28/31) secretory EINs were associated with circulating progestins. Rare exceptions were observed, suggesting that secretory EIN may occur as a hormone-independent phenomenon. Circulating progestins are not sufficient, however, to induce EIN secretory differentiation, as 26% (10/38) of EIN within a secretory background were of the ordinary (non-secretory) type. EIN patients with secretory endometrium in the background are younger (averaging 45 years) than the aggregate group of all patients with EIN (53 years in previously published studies) and are often premenopausal with a cyclical source of endogenous progestins. Involution of EIN during follow-up was more frequent (81%, 17/21) for those with a secretory background at the time of initial EIN diagnosis compared with historical averages (25%, 36/142). These results suggest a potential role for endogenous progesterone, as well as therapeutic progestins, in modulating EIN outcomes.

Cystic lesions of the pancreas: clinical and pathologic review of cases in a five year period.

CONTEXT: Cystic lesions of the pancreas represent an important subgroup of pancreatic tumors. The characterization of these lesions has evolved in recent years, and will continue to change according to the increasing number of biopsies and resections performed. DESIGN: Pancreatectomy specimens containing cystic lesions collected over a five-year period were reviewed. MAIN OUTCOME MEASURES: Demographic and pathologic features were recorded. SETTING: Cases were subclassified in diagnostic categories and were grouped according to the nature of the lesion (non-neoplastic vs. neoplastic). RESULTS: Of 361 pancreatic lesions, 97 cysts corresponding to 95 patients were studied. The patients' mean age was 60 years. Sixty two cysts (63.9%) occurred in women. Among the 97 cysts, five (5.2%) were non-neoplastic and 92 (94.8%) were neoplastic (59.8% benign, 17.5% borderline, 17.5% malignant). Intraductal papillary mucinous neoplasm was the most common diagnosis (n=51; 52.6%) followed by serous cystic neoplasm (n=20; 20.6%) and mucinous cystic neoplasm (n=13; 13.4%). Frequency of female gender was higher and age was lower in the borderline lesions (P=0.001 and P=0.002, respectively). Tumor size was significantly lower in benign neoplastic lesions (P=0.045). Incidental identification was more frequent in benign lesions (P=0.028), whereas malignant lesions were more frequently symptomatic (P=0.001). CONCLUSION: Cystic lesions are found in 20.6% of all pancreatectomy specimens. Among this heterogeneous group, benign neoplasms predominate, particularly those with mucinous lining. Age at presentation, gender, location and tumor size are highly variable, with the exception of solid pseudopapillary tumor. Clinical presentation, diagnostic imaging and laboratory data should be consistently reported to improve the therapeutic approach.

Intestinal candidiasis: an uncommon cause of necrotizing enterocolitis (NEC) in neonates.

Candida albicans produces intestinal perforation and necrotizing enterocolitis (NEC) in preterm newborns. We reviewed pathology files in neonates with a diagnosis of NEC (10-year period), gathered history, and reviewed histological materials. Of 249 autopsies, two (0.8%) had systemic candidiasis. From 66 surgical cases with a diagnosis of NEC, five cases (7.5%) had intestinal candidiasis. Candida albicans grew in pre- and post-mortem blood, lung, or peritoneal fluid in all cases. Histologically, the small bowel revealed fungi, sometimes intravascular. Systemic candidiasis with intestinal involvement is an important complication of prematurity and a prevalent cause of sepsis. The presence of intraluminal fungi with associated vascular occlusion may lead to bowel ischemia, necrosis, and perforation.