M. Ruhul Quddus

Clear Cell Endometrial Carcinoma In Situ (CCEIC) Exists!

Endometrial endometrioid adenocarcinoma with a malignant squamous component: is the unusual metastatic pattern unique of these tumors?

The FIGO scheme is currently applied for tumor grading of endometrioid adenocarcinoma. The current report presents a series of ten cases of endometrioid carcinomas that when applying the FIGO grading does not fully convey the true biological nature of the disease. The squamous component of these tumors is malignant; it constitutes the predominant invasive component, and it often metastasizes to unconventional sites. Half of the cohort developed distant disease recurrence within 2 years, even those with early-stage disease. Somatic mutations were analyzed, targeting 101 genes in all ten cases, and mutations in PTEN, MMR, PIK3CA, ATM, RB1, and TP53 genes were detected, often multiple mutations in the same case. None of the cases revealed unique molecular signatures or previously unreported gene mutations. Immunohistochemical staining for beta-catenin showed aberrant nuclear staining in eight of ten cases and remaining two showed cytoplasmic and membranous staining. Aggressive behavior and unusual sites of metastases are observed in this series even in low-grade tumor. The FIGO grading on smaller samples may be deceptive for these cases. Even if FIGO is applied, the pathology report should emphasize the malignant squamous component and its potential significance so that the gynecologic oncology team can formulate appropriate adjuvant treatment upfront. This case series argues that this histology should be regarded as a high-grade endometrioid carcinoma and can show unusual metastatic patterns. Further research is needed with more cases within this histologic subtype to guide recommendations on adjuvant therapies for this aggressive tumor type.

Ever Expanding Morphologic Patterns of Mesonephric-like Adenocarcinomas of the Uterine Corpus: A Report of Two Tumors and a Brief Review of the Literature

Mesonephric-like adenocarcinoma (MLA) of the endometrium shows a variety of morphologic appearances, including small glands, tubules with eosinophilic materials in the lumen, prominent papillary patterns, spindled cells, solid formations, and corded and hyalinized patterns. Unique morphology, characteristic immunohistochemical staining patterns, molecular alterations, and awareness of the pathologists make it possible to identify this tumor accurately. This report of two additional morphologic patterns, intestinal goblet cells mimicking intestinal-type mucinous carcinoma and squamous differentiation with spindle and epithelioid cells mimicking carcinosarcoma of the endometrium will expand the literature on MLA.

Metaplastic Potential of Müllerian Epithelia in Full Display!

Recurrent Primary Paget Disease of Vulva with Paget-Like Epithelial Cells in Papillary Dermis: Displaced or Invasion?

While histological diagnosis of Paget disease of vulva is mostly straightforward, identifying and confirming invasion can be challenging. Often invasion is accompanied by epidermal hyperplasia, marked inflammatory response and desmoplastic reaction. Diagnosis of invasion in Paget disease portends a poor outcome. We report findings from a recurrent primary vulvar Paget disease where overall histomorphology of possible invasive disease is unusual and raises a possibility of displacement of Paget cells in the dermis. We compare histology of the index case with known invasive vulvar Paget disease cases retrieved from our pathology archives. Unique histomorphology in the index case suggests a possibility of previous excision related dermal displacement of Paget cells.