The 1000 Mitoses Project: A Consensus-Based International Collaborative Study on Mitotic Figures Classification.

The identification of mitotic figures is essential for the diagnosis, grading, and classification of various different tumors. Despite its importance, there is a paucity of literature reporting the consistency in interpreting mitotic figures among pathologists. This study leverages publicly accessible datasets and social media to recruit an international group of pathologists to score an image database of more than 1000 mitotic figures collectively.

Merkel cell polyomavirus and p63 status in Merkel cell carcinoma by immunohistochemistry: Merkel cell polyomavirus positivity is inversely correlated with sun damage, but neither is correlated with outcome.

The aim of this study was to determine the frequency of Merkel cell polyomavirus (MPyV) and p63 positivity by immunohistochemistry in a large cohort of primary Merkel cell carcinoma (MCC) from a region with high rates of actinic damage. We also aimed to determine whether there is any relationship between these markers and histological correlates of chronic sun exposure and to identify whether these markers have prognostic significance in our population. Ninety-five cases of primary cutaneous MCC were identified and stained with immunohistochemical markers for MPyV and p63.

Challenging diagnosis of a jejunal adenocarcinoma with ovarian metastasis: report of an unusual case.

We report the first documented case of ovarian metastasis from a jejunal primary adenocarcinoma in an Australian patient. The presentation was unusual, initially a suspicious abdominal nodule in the epigastric area, which turned out to be an adenocarcinoma of possible intestinal origin. Gastroscopy and colonoscopy were performed with no suspicious lesion identified.

Ovarian teratoma associated with anti-N-methyl D-aspartate receptor encephalitis: a report of 5 cases documenting prominent intratumoral lymphoid infiltrates.

Anti-N-methyl D-aspartate receptor (NMDAR) encephalitis is a recently described severe neurological disorder predominantly affecting young women, which presents with psychosis, memory deficits, seizures, and encephalopathy, often requiring prolonged hospitalization. The condition is frequently associated with an underlying neoplasm, most often an ovarian teratoma, and in such cases appears to be a para-neoplastic, immune-mediated encephalopathy. The histologic features of the teratomas associated with anti-NMDAR encephalitis have seldom been described in detail.