Platelet transfusion: a clinical practice guideline from the AABB

BACKGROUND: The AABB (formerly, the American Association of Blood Banks) developed this guideline on appropriate use of platelet transfusion in adult patients. METHODS: These guidelines are based on a systematic review of randomized, clinical trials and observational studies (1900 to September 2014) that reported clinical outcomes on patients receiving prophylactic or therapeutic platelet transfusions. An expert panel reviewed the data and developed recommendations using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) framework. RECOMMENDATION 1: The AABB recommends that platelets should be transfused prophylactically to reduce the risk for spontaneous bleeding in hospitalized adult patients with therapy-induced hypoproliferative thrombocytopenia. The AABB recommends transfusing hospitalized adult patients with a platelet count of 10 × 109 cells/L or less to reduce the risk for spontaneous bleeding. The AABB recommends transfusing up to a single apheresis unit or equivalent. Greater doses are not more effective, and lower doses equal to one half of a standard apheresis unit are equally effective. (Grade: strong recommendation; moderate-quality evidence). RECOMMENDATION 2: The AABB suggests prophylactic platelet transfusion for patients having elective central venous catheter placement with a platelet count less than 20 × 109 cells/L. (Grade: weak recommendation; low-quality evidence). RECOMMENDATION 3: The AABB suggests prophylactic platelet transfusion for patients having elective diagnostic lumbar puncture with a platelet count less than 50 × 109 cells/L. (Grade: weak recommendation; very-low-quality evidence). RECOMMENDATION 4: The AABB suggests prophylactic platelet transfusion for patients having major elective nonneuraxial surgery with a platelet count less than 50 × 109 cells/L. (Grade: weak recommendation; very-low-quality evidence). RECOMMENDATION 5: The AABB recommends against routine prophylactic platelet transfusion for patients who are nonthrombocytopenic and have cardiac surgery with cardiopulmonary bypass. The AABB suggests platelet transfusion for patients having bypass who exhibit perioperative bleeding with thrombocytopenia and/or evidence of platelet dysfunction. (Grade: weak recommendation; very-low-quality evidence). RECOMMENDATION 6: The AABB cannot recommend for or against platelet transfusion for patients receiving antiplatelet therapy who have intracranial hemorrhage (traumatic or spontaneous). (Grade: uncertain recommendation; very-low-quality evidence).(AU)

Cancerization of small ectatic ducts of the breast by ductal carcinoma in situ cells with apocrine snouts: a lesion associated with tubular carcinoma.

Small ectatic ducts lined by atypical ductal cells with apocrine snouts occasionally have been observed in association with tubular carcinoma; some pathologists have considered these carcinomas to be a form of ductal carcinoma in situ (DCIS). Thirty-two cases of tubular carcinoma, 41 of invasive grade 1 ductal carcinoma with DCIS, 40 of invasive grade 1 ductal carcinoma without DCIS, 40 of invasive grade 3 ductal carcinoma, 40 of invasive lobular carcinoma, 20 of well-differentiated DCIS, and 80 of fibrocystic changes were examined to determine the relationship between the lesion formed by atypical ductal cells with apocrine snouts and invasive carcinoma, DCIS, and benign breast changes. Seventeen cases contained lesions formed by atypical ductal cells with apocrine snouts: 14 were associated with tubular carcinoma (43.7%), and 3 with invasive grade 1 ductal carcinoma (3.7%). In six invasive carcinomas, the associated DCIS was formed by cells identical to those within the lesion. These lesions were found at the periphery of the invasive carcinoma and adjacent to the DCIS. The lesions were probably composed of low-grade intraductal malignant epithelial cells, which partially involve small ectatic ducts and are often adjacent structures as a form of cancerization. This cytologic and architectural form of DCIS appears to be related to an invasive carcinoma that is usually of tubular subtype. Attention to this form of cancerization by malignant intraductal cells, especially with regard to specimen surgical margins, is imperative when a tubular carcinoma is encountered. If a pathologist encounters only this lesion in a partially sampled breast biopsy specimen, additional (or all) tissue should be submitted for histologic evaluation to ensure that an invasive carcinoma is not missed. This lesion needs to be distinguished from the frequent, benign, columnar alteration within lobules and small ectatic ducts.

bcr gene rearrangement analysis in myeloproliferative disorders other than chronic myelogenous leukemia.

The bcr gene rearrangement resulting from the Philadelphia translocation is diagnostic of chronic myelogenous leukemia (CML) and is considered the hallmark of this myeloproliferative disorder (MPD) at the molecular level. The other MPDs, essential thrombocythemia (ET), polycythemia vera (PV), agnogenic myeloid metaplasia (AMM), and unclassified MPD, share morphologic features with CML, making the diagnosis difficult in cases with considerable morphologic overlap. In such cases, molecular analysis becomes essential for accurate diagnosis. We report results of bcr analysis by Southern hybridization in 37 patients with MPDs other than CML: ET (20 cases), PV (seven cases). unclassified MPD (nine cases), as well as in one case of chronic myelomonocytic leukemia (CMML). bcr negativity ruled out CML in 36 cases, confirming the morphologic diagnosis. In one case diagnosed as ET. bcr gene rearrangement was diagnostic of CML. The correct diagnosis made possible a different therapeutic approach in this young patient and resulted in cure after allogeneic bone marrow transplantation. The existence of such cases makes the use of molecular analysis essential in the evaluation of MPDs, even when the morphologic features do not unequivocally support the diagnosis of CML, as in this patient.