Pathologist Concordance for Ovarian Carcinoma Subtype Classification and Identification of Relevant Histologic Features Using Microscope and Whole Slide Imaging.

CONTEXT.­: Despite several studies focusing on the validation of whole slide imaging (WSI) across organ systems or subspecialties, the use of WSI for specific primary diagnosis tasks has been underexamined. OBJECTIVE.­: To assess pathologist performance for the histologic subtyping of individual sections of ovarian carcinomas using a light microscope and WSI. DESIGN.­: A panel of 3 experienced gynecologic pathologists provided reference subtype diagnoses for 212 histologic sections from 109 ovarian carcinomas based on optical microscopy review. Two additional attending pathologists provided diagnoses and also identified the presence of a set of 8 histologic features important for ovarian tumor subtyping. Two experienced gynecologic pathologists and 2 fellows reviewed the corresponding WSI images for subtype classification and feature identification. RESULTS.­: Across pathologists specialized in gynecologic pathology, concordance with the reference diagnosis for the 5 major ovarian carcinoma subtypes was significantly higher for a pathologist reading on a microscope than each of 2 pathologists reading on WSI. Differences were primarily due to more frequent classification of mucinous carcinomas as endometrioid with WSI. Pathologists had generally low agreement in identifying histologic features important to ovarian tumor subtype classification with either an optical microscopy or WSI. This result suggests the need for refined histologic criteria for identifying such features. Interobserver agreement was particularly low for identifying intracytoplasmic mucin with WSI. Inconsistencies in evaluating nuclear atypia and mitoses with WSI were also observed. CONCLUSIONS.­: Further research is needed to specify the reasons for these diagnostic challenges and to inform users and manufacturers of WSI technology.

Immune checkpoint status and tumor microenvironment in vulvar squamous cell carcinoma.

Vulvar squamous cell carcinoma accounts for 5% of cancers of the female genital tract. Current guidelines recommend wide local excision with negative surgical margins as the standard treatment. However, the extent of the tumor-free resection margin after wide local excision is still controversial in many cases. Drugs targeting immune checkpoints such as PD-1 or its ligand PD-L1 have potential clinical utility in these patients. We examined the expression of PD-L1 in tumor cells and immune cells, as well as the proportion of PD-1, CD8, and FOXP3 positive lymphocytes. Twenty-one cases of invasive vulvar squamous cell carcinomas were reviewed. Whole slides of representative formalin-fixed, paraffin-embedded archival material were used for analysis. Odds ratios (OR) and hazard ratios (HR) were used to estimate risk for disease recurrence, overall mortality, and cancer mortality. PD-L1 expression was found in 43% of tumor cells, with higher proportions in intratumoral (67%) and peritumoral (81%) immune cells. OR and HR for disease recurrence and cancer mortality were higher in tumors with higher CD8 expression. OR and HR for overall mortality were also higher in tumors with higher PD-L1 and CD8 expression. In conclusion, nearly half of cases were PD-L1 positive in tumor cells with over two-third of cases demonstrating PD-L1 positivity in immune cells. Immunohistochemical expression of PD-L1 and CD8 could be used to suggest higher risk of disease recurrence, overall mortality, and cancer mortality. Furthermore, our data contributes to the growing evidence that targeting the PD-1/PD-L1 pathway may be beneficial in vulvar squamous cell carcinomas.

Genetically Related Choriocarcinoma Developing 5 Yr After a Complete Hydatidiform Mole and Simulating a Cornual Ectopic Pregnancy.

Persistent gestational trophoblastic disease can arise from any type of antecedent pregnancy, including molar and tubal pregnancies. While most cases of persistent gestational trophoblastic disease present within the first year following initial diagnosis, recurrence has rarely been reported many years after initial diagnosis. Distinguishing recurrence from a new independent lesion is clinically important. A 25-yr-old woman presented with a mass in the right uterine cornu that was discontiguous with the endometrial cavity and was associated with an elevated serum human chorionic gonadotropin level. She had a history of an invasive complete hydatidiform mole with lung involvement treated with chemotherapy 5 yr prior. Wedge resection of the right cornu was performed due to concern for a cornual ectopic pregnancy. Pathologic evaluation demonstrated a choriocarcinoma. Molecular genotyping confirmed the tumor as recurrent disease genetically related to the prior complete hydatidiform mole. She completed 4 cycles of EMA-CO therapy, and has been disease-free with undetectable serum human chorionic gonadotropin level for 2 yr.

Atypical Proliferative (Borderline) Serous Tumor in the Brain: A Case Report.

A 59-year-old woman with a remote history of invasive ductal carcinoma of the breast was found on a follow-up computed tomography scan of her brain to have a 1-cm lesion in the right frontal lobe in 2008. In the ensuing years, before her current admission, multiple imaging studies of the brain revealed that the lesion was stable and it was, therefore, interpreted as a small area of encephalomalacia related to a thrombosed cortical vein, a cavernoma, or treated metastatic breast cancer. In 2013, the patient underwent a bilateral salpingo-oophorectomy for ovarian tumors that were diagnosed as bilateral serous cystadenofibromas. A partial omentectomy showed no evidence of implants. In June 2016, the brain lesion was completely excised and diagnosed as an atypical proliferative (borderline) serous tumor. Immunohistochemical staining demonstrated that the tumor cells were immunoreactive for Pax8, WT-1, ER, and CK-7 and negative for Gata-3, PR, TTF-1, CDX-2, Napsin A, and CK-20, which was consistent with that diagnosis. We present a brief review of possible mechanisms to account for this unusual presentation and speculate that the most likely one is exfoliation of fallopian tube epithelial cells into the peritoneal cavity, which then gain access to lymphatics resulting in cells implanting in the brain and subsequently progressing to an atypical proliferative (borderline) serous tumor.

Concordance of DNA methylation profiles between breast core biopsy and surgical excision specimens containing ductal carcinoma in situ (DCIS).

The utility and reliability of assessing molecular biomarkers for translational applications on pre-operative core biopsy specimens assume consistency of molecular profiles with larger surgical specimens. Whether DNA methylation in ductal carcinoma in situ (DCIS), measured in core biopsy and surgical specimens are similar, remains unclear. Here, we compared genome-scale DNA methylation measured in matched core biopsy and surgical specimens from DCIS, including specific DNA methylation biomarkers of subsequent invasive cancer. DNA was extracted from guided 2mm cores of formalin fixed paraffin embedded (FFPE) specimens, bisulfite-modified, and measured on the Illumina HumanMethylation450 BeadChip. DNA methylation profiles of core biopsies exhibited high concordance with matched surgical specimens. Within-subject variability in DNA methylation was significantly lower than between-subject variability (all P<2.20E-16). In 641 CpGs whose methylation was related with increased hazard of invasive breast cancer, lower within-subject than between-subject variability was observed in 92.3% of the study participants (P<0.05). Between patient-matched core biopsy and surgical specimens, <0.6% of CpGs measured had changes in median DNA methylation >15%, and a pathway analysis of these CpGs indicated enrichment for genes related with wound healing. Our results indicate that DNA methylation measured in core biopsies are representative of the matched surgical specimens and suggest that DCIS biomarkers measured in core biopsies can inform clinical decision-making.

DNA methylation in ductal carcinoma in situ related with future development of invasive breast cancer.

BACKGROUND: Ductal carcinoma in situ (DCIS) is a heterogeneous, pre-invasive lesion associated with an increased risk for future invasive ductal carcinoma. However, accurate risk stratification for development of invasive disease and appropriate treatment decisions remain clinical challenges. DNA methylation alterations are early events in the progression of cancer and represent emerging molecular markers that may predict invasive recurrence more accurately than traditional measures of DCIS prognosis. RESULTS: We measured DNA methylation using the Illumina HumanMethylation450K array of estrogen-receptor positive DCIS (n = 40) and adjacent-normal (n = 15) tissues from subjects in the New Hampshire Mammography Network longitudinal breast imaging registry. We identified locus-specific methylation differences between DCIS and matched adjacent-normal tissue (95,609 CpGs, Q < 0.05). Among 40 DCIS cases, 13 later developed invasive disease and we identified 641 CpG sites that exhibited differential DNA methylation (P < 0.01 and median |Ƨ| > 0.1) in these cases compared with age-matched subjects without invasive disease. The set of differentially methylated CpG loci associated with disease progression was enriched in homeobox-containing genes (P = 1.3E-09) and genes involved with limb morphogenesis (P = 1.0E-05). In an independent cohort, a subset of genes with progression-related differential methylation between DCIS and invasive breast cancer were confirmed. Further, the functional relevance of these genes' regulation by methylation was demonstrated in early stage breast cancers from The Cancer Genome Atlas database. CONCLUSIONS: This work contributes to the understanding of epigenetic alterations that occur in DCIS and illustrates the potential of DNA methylation as markers of DCIS progression.

MCM2/TOP2A (ProExC) immunohistochemistry as a predictive marker in head and neck mucosal biopsies.

Mucosal biopsies from the head and neck are often small and poorly oriented, which impedes diagnostic interpretation, especially in patients with a history of cancer, being monitored for recurrence. A cocktail of antibodies targeted against DNA topoisomerase IIA and mini-chromosome maintenance protein 2 (MCM2/TOP2A, ProExC), markers of aberrant S-phase induction, have been used with success as a diagnostic adjunct in the evaluation of squamous dysplasia of the uterine cervix. We tested the utility in head and neck biopsies to see if ProExC could be used to discriminate reactive/inflammatory from true pre-neoplasia. Sixty-four archival biopsies were selected from patients who presented to the surgeon with an indication for biopsy to "rule out" dysplasia. Histologically, all biopsies showed nonspecific atypia that was difficult to discriminate from dysplasia. Twenty-three of the patients progressed to squamous carcinoma and the rest remained benign over five years follow-up. Cases stained with ProExC by IHC methods showed a significant pattern of expression (p=0.026). The staining was greatest in patients without a history of prior head and neck cancer but was not significant. Our results show that ProExC, used in conjunction with the H&E slide, can enhance the predictive power of a mucosal biopsy in a cohort of patients.