Erdheim-Chester Disease: A Case Report of BRAF V600E-Negative, MAP2K1-Positive ECD Diagnosed by Blood Next-Generation Sequencing Assay and a Brief Literature Review.

Erdheim-Chester disease (ECD) is a rare type of non-Langerhans cell histiocytosis. However, its prevalence has increased significantly the past few years due to increased awareness about the disorder, and 1500 cases have been reported worldwide. It is often a multisystemic disease with skeletal, cardiovascular, urologic, renal, retroperitoneal, pulmonary, endocrine, cutaneous, and neurologic involvement. MAPK pathway mutations, such as BRAF activating and MAP2K1 mutations, play a key role in its pathogenesis. In addition to the characteristic clinical, radiological, and histopathological findings, identifying underlying mutations helps diagnose and treat patients with highly effective targeted therapies such as BRAF and MEK inhibitors. We report a case of a man, aged 55 years, with an extensive and prolonged course of an unexplained multisystemic disease, later diagnosed with BRAF V600E-negative and MAP2K1-positive ECD on cell-free DNA testing. Additionally, we review common clinical manifestations, mutations, diagnoses, and targeted therapies for ECD.

Biliary tract large cell neuroendocrine carcinoma: current evidence.

BACKGROUND: Primary neuroendocrine carcinomas of the gallbladder and biliary tract are rare, with pure large cell neuroendocrine carcinomas (LCNEC) being exceedingly rare and with a particularly poor prognosis. METHODS: We performed a review of published data on biliary tract large cell neuroendocrine carcinomas in PubMed. RESULTS: Preliminary search revealed over 2000 results but we found only 12 cases of pure large cell neuroendocrine carcinomas of biliary tract noted in literature to date. Because it commonly presents with non-specific symptoms of abdominal pain and jaundice, diagnosis is made after resection with histo-pathological and immunohistochemical analysis. These cancers are particularly aggressive with high recurrence rates, most often presenting with metastasis to regional lymph nodes and/or the liver resulting in a poor prognosis. Overall, complete surgical excision with systemic chemotherapy is the treatment mainstay. If the cancer is unresectable due to multiple metastases, medical management with systemic chemotherapy is the primary treatment modality. CONCLUSION: The prognosis of hepatobiliary LCNEC remains poor with median survival of only 11 months from initial diagnosis. Studies focusing on high grade neuroendocrine carcinoma are needed to enhance our understanding of biology and therapeutics in this rare but aggressive cancer.

Immunohistochemical expression of hormone receptors in melanoma of pregnant women, nonpregnant women, and men.

The survival advantage of women over men with cutaneous melanoma and the reports of accelerated progression of melanoma during pregnancy have led to studies of the effect of hormones and hormone receptors on the development and progression of melanoma. However, the results are inconclusive. We therefore evaluated the expression of estrogen receptor α, estrogen receptor ß, and androgen receptor in melanomas of stage- and age-matched pregnant women, nonpregnant women, and men by immunohistochemical analysis of formalin-fixed, paraffin-embedded archival tissues. In addition, we also assessed the mitotic rate using the antiphosphohistone H3 antibody by immunohistochemistry. Our data showed a trend of more frequent expression of estrogen receptor ß in the melanomas of pregnant patients than in the melanomas of male patients, without a significant difference observed between pregnant and nonpregnant women. However, no association between the expression of estrogen receptor ß and survival was observed. The small cohort may have limited the statistical power of the study, and large-scale studies are needed to elucidate the potential role of estrogen receptor ß as a prognostic marker of melanoma.