We have posted updates of the following topics:CNS tumor > Gliomas, glioneuronal tumors, and neuronal tumors > Pediatric-type diffuse high grade gliomas > Diffuse low grade glioma, MAPK pathway altered
by Mariana Voudouri, M.D., George Zanazzi, M.D., Ph.D.
Topic summary: Low grade, infiltrative, pediatric glioma with an alteration in a MAP kinase pathway gene such as FGFR1 or BRAF; tumor is IDH wild type, histone H3 wild type and does not have a homozygous deletion of CDKN2A. Arises anywhere in the central nervous system, often in the cerebral hemispheres or posterior fossa. Predominantly in children. Prognostic factors currently unclear but rarely undergo malignant transformation. Treatment: surgical resection, although this may be limited by involvement of critical brain structures.
Prostate gland & seminal vesicles > Stromal tumors > STUMP
by Kenneth A. Iczkowski, M.D.
Topic summary: Stromal tumor of uncertain malignant potential (STUMP) is a term that should be reserved for a category of benign lesions that almost never metastasize. Rare prostatic tumors with stromal degenerative atypia featuring vacuolated nuclei. STUMP occurs in a broad age range with median age of 58 – 61 years. CD34, Ki67 and cytokeratin are the most helpful immunostains. Proliferative index as measured by mitotic count or Ki67 may presage worse outcome, although if high enough, sarcoma should be considered. Simple excision is the usual treatment approach.
Skin melanocytic tumor > Melanoma > Lentigo maligna melanoma
by Joseph Gillam, M.D., Jennifer Crimmins, M.D., Mark Mochel, M.D.
Topic summary: Subtype of melanoma arising on chronically sun damaged skin and appearing as an irregular pigmented macule, corresponding to an intraepidermal proliferation of atypical melanocytes; over time, may develop foci that are indurated, papular or nodular, indicating tumorigenic growth. Older patients, usually over 50. Prognosis is correlated with presence and depth of invasion, mitotic rate among invasive cells and presence / absence of ulceration; excellent if noninvasive and completely excised. Treatment: complete excision, accomplished via wide local excision, staged surgical excision or Mohs micrographic surgery.
Stains & CD markers > CD23
by Mihaly Sulyok, M.D., Ph.D., Christian M. Schürch, M.D., Ph.D.
Topic summary: CD23 is a low affinity immunoglobulin E (IgE) receptor. Differentiates small lymphocytic lymphoma (SLL) / chronic lymphocytic leukemia (CLL) (CD23+) from mantle cell lymphoma or MALT lymphoma (CD23-). Pathophysiology: after physiologic germinal cell development, the follicular dendritic cell meshwork expands and follicular dendritic cells in the light zone of the germinal center become CD23 positive. High expression on B cells in peripheral blood is associated with bullous pemphigoid. Diffuse cell membrane staining, cytoplasmic staining.
Transfusion medicine > Therapeutic apheresis > Red blood cell exchange
by Timothy Carll, M.D., Geoffrey Wool, M.D., Ph.D.
Topic summary: Automated technique that separates red blood cells from whole blood and replaces with replacement fluid. When replacement fluid is donor packed red blood cells (pRBCs), the procedure is referred to as red blood cell exchange; when replacement fluid is crystalloid or colloid solution, the technique is referred to as erythrocytapheresis. Therapeutic technique directed at correcting disease driven by congenital or acquired abnormality of red blood cells. Indications for red blood cell exchange include sickle cell disease, parasitemias and ABO incompatibility.