We have posted updated reviews of the following topics:CD Markers > CD27
by Frido Bruehl, M.D., Christian M. Schürch, M.D., Ph.D.
Topic summary: CD27 is a costimulatory receptor of the TNF receptor superfamily expressed on lymphocyte, whose ligand is CD70. CD27 deficiency should be considered in patients with immunodeficiencies and CD27 staining in flow cytometry can help detect immunodeficiencies.
Kidney nontumor > Vascular disease > Thrombotic microangiopathy and acute endothelial injury > Scleroderma renal disease
by Christine M. Lee, M.D., Jonathan E. Zuckerman, M.D., Ph.D.
Topic summary: A spectrum of small arterial and arteriolar vasculopathy ranging from mild fibrointimal thickening to thrombotic microangiopathy. Scleroderma related thrombotic microangiopathy is characterized by mucoid intimal edema, onion skin-like intimal proliferation, fibrinoid necrosis and thrombosis. Glomerular changes include ischemic collapse and endothelial swelling and thrombosis, acutely and basement membrane duplication, chronically. Ischemic injury to tubules results in acute tubular injury or necrosis and eventually, interstitial fibrosis and tubular atrophy.
Ovary > Serous tumors > Low grade serous carcinoma
by Erna Forgó, M.D., Teri A. Longacre, M.D.
Topic summary: Epithelial carcinoma of serous cell lineage, usually with distinctive patterns of invasion and low grade malignant cytologic atypia. Often bilateral ovarian masses that are solid or solid and cystic with calcifications. Precursor lesion is often a borderline serous tumor. KRAS and BRAF mutations in 50 – 60% of cases.
Skin nontumor > Infectious disorders > Molluscum contagiosum
by Osward Y. Carrasquillo, M.D., M.P.H., Jorge L. Sánchez, M.D.
Topic summary: Self limited infectious dermatosis that most commonly affects children and immunocompromised patients, usually (98%) caused by MCV1. In contrast to most double stranded DNA viruses, poxvirus replicates in the cytoplasm. Characteristic Henderson-Paterson bodies, also known as molluscum bodies, are large (up to 35 microns) intracytoplasmic eosinophilic inclusion on keratinocytes.
Stains & molecular markers > BCOR
by Isidro Machado, M.D., Ph.D., Antonio Llombart-Bosch, M.D., Ph.D.
Topic summary: BCL6 transcriptional corepressor (BCOR) is located at Xp11.4 locus. Encodes a protein which is involved in transcriptional repression in association with BCL6 and epigenetic silencing through polycomb repressive complex 1 (PRC1). BCOR immunohistochemistry can be used diagnostically to separate tumors with BCOR gene alteration (rearrangement or internal tandem duplication) from their histological mimics (mainly the group of small / ovoid round cell sarcomas).