We have posted updates of the following topics:Liver & intrahepatic bile ducts > Hepatocellular carcinoma > HCC – sarcomatoid variant
by Daffolyn Rachael Fels Elliott, M.D., Ph.D., Ryan M. Gill, M.D., Ph.D.
Topic summary: Hepatocellular carcinoma (HCC) variant, partially or entirely composed of malignant spindle cells. Area of conventional HCC usually present to support the diagnosis. Patients tend to be older and predominantly male. Associated with expression of genes related to epithelial mesenchymal transition (EMT) and inflammation. Sarcomatoid change is more frequent in patients undergoing repeated chemotherapy or transarterial chemoembolization. Larger tumor size, advanced stage and higher incidence of extrahepatic disease compared to classic HCC. Worse prognosis compared to classic HCC. Treatment: surgical resection, radiofrequency ablation, transarterial chemoembolization (TACE), transplantation.
Lung > Infectious > Bacterial > Tuberculosis
by Hui-Hua Li, M.D., Ph.D., Jefree J. Schulte, M.D.
Topic summary: Infectious disease caused by Mycobacterium tuberculosis; disease can be manifested as primary, secondary and miliary tuberculosis. Hallmark is necrotizing granulomatous inflammation, composed of central necrotic zone surrounded by epithelioid histiocytes and Langhans type giant cells. Most commonly affects the respiratory system but other systems can be involved in disseminated disease. Risk factors: immunosuppression, including HIV / AIDS, chronic immunosuppressive therapy or an inborn immunodeficiency; occupational: mining, construction work, pneumoconiosis (silicosis). Suboptimal treatment and multidrug resistant strains contribute to morbidity and mortality.
Skin nonmelanocytic tumor > Benign (nonmelanotic) epidermal tumors or tumor-like lesions > Dermatosis papulosa nigra
by Negin Farsi, M.D., Sara C. Shalin, M.D., Ph.D.
Topic summary: Benign epidermal growth presented as hyperpigmented or skin colored papules on face and neck, most commonly found on patients with darker phototypes (Fitzpatrick type IV, V or VI). Generally asymptomatic papules without crusting, scaling or ulceration. Clinical: filiform, verrucous or pedunculated pigmented papule; histology: acanthosis, papillomatosis, hyperkeratosis and hyperpigmentation. Onset often late in adolescence, increasing numbers with age, common in adulthood and age > 60 years. No risk for transforming to malignancy; never regresses spontaneously. Treatment not necessary; for cosmetic purposes.
Stains & CD markers > CD30
by Mario L. Marques-Piubelli, M.D., Roberto N. Miranda, M.D.
Topic summary: CD30 is a transmembrane, type I, glycoprotein receptor from the tumor necrosis factor receptor (TNFR) superfamily. CD30 gene is located at 1p36, close to TNFR2 and OX40. BerH2: most commonly used clone to fabricate the antibody and has good correlation with mRNA levels of CD30; composed of 2 linear epitopes with identical sequence. Typically expressed in cytoplasmic / membrane compartments. Targetable biomarker: high expression by neoplastic cells, low expression by normal cells, extracellular localization. Used in differential diagnosis and assessment of lymphomas in which the neoplastic cells universally express CD30.
Stains & CD markers > Uroplakin II
by Harsh Batra, M.B.B.S., D.C.P., D.N.B., Anil Parwani, M.D., Ph.D., M.B.A.
Topic summary: Uroplakin II, a 15kDa protein that is part of the uroplakin family (UP1a, UP1b, UPII and UPIII), which forms the urothelial plaque covering the apical surface of the urothelium. Uroplakins are terminal differentiation products that are exclusively expressed in urothelial cells. Highly specific and moderately sensitive for urothelial carcinomas. Helpful in ascertaining the primary origin as urothelium, especially in cases where GATA3 is inconclusive. Moderate to strong, predominantly membranous and cytoplasmic staining reaction in virtually all umbrella cells in the urethra. Loss of UPII seen more frequently in higher grade lesions.