A diagnostically challenging case of CD8+ primary cutaneous gamma/delta T-cell lymphoma.

Primary cutaneous gamma/delta T-cell lymphoma (PCγδTCL) is a rare form of cutaneous lymphoma characterized by abnormal clonal proliferation of mature, activated gamma-delta T cells expressing the γδ heterodimer of the T-cell receptor (TCR). As an entity, PCγδTCL has recently undergone diagnostic revision since its introduction in the 2008 WHO classification of cutaneous lymphomas and confirmedin 2016. Nonetheless, diagnosis remains difficult both clinically and histologically, given its broad range of clinical manifestations and immunohistochemical phenotypes. Herein, we present a rare case of CD8+ PCγδTCL with a discussion highlighting theheterogeneity within this entity.

Evaluation of anti-thrombomodulin antibody as a tumor marker for vascular neoplasms.

BACKGROUND: Various endothelial markers are available for the evaluation of vascular tumors and malformations, including anti CD34, anti-CD31, von Willebrand factor (vWF), and anti-thrombomodulin (anti-TM) antibodies. All have their limitations, and we sought to compare the utility of anti-TM antibody as a marker for several types of vascular neoplasms vs. previously established endothelial markers. METHODS: We examined immunostaining profiles of 30 capillary hemangiomas, 10 pyogenic granulomas, five tufted angiomas, 17 Kaposi's sarcomas, and nine angiosarcomas. Immunostains for TM, CD34, and vWF were carried out using a labeled streptavidin-biotin peroxidase detection system. RESULTS: Anti-TM antibody showed moderately intense immunostaining in 89% of benign and malignant vascular neoplasms. Anti-CD34 antibody showed moderate to diffuse immunostaining in 98% of vascular neoplasms, and vWF showed weak focal staining in 84% of all vascular neoplasms examined. CONCLUSION: Anti-TM antibody proved to be a sensitive marker for both benign and malignant vascular neoplasms. While not as sensitive as anti-CD34, it may have some advantages in specificity that would make it a more reliable vascular tumor marker in certain situations.