ALK-negative anaplastic large cell lymphoma primarily involving the bronchus: a case report and literature review.

Anaplastic large cell lymphoma (ALCL) is a mature T cell lymphoma with characteristic morphologic, immunophenotypic and cytogenetic features. Current WHO classification includes anaplastic lymphoma kinase (ALK)-positive and ALK-negative variants. ALCL rarely presents with obstructive symptoms of the main airway. In addition to reporting a HIV-associated bronchial ALK-negative ALCL in a 44 year-old female, our literature review identified eight cases of bronchial ALCL with several interesting clinicopathological features, including: 1) a female predominance (67%); 2) two thirds of patients younger than 18 years old; 3) uniformly presented with respiratory symptoms and progressed to respiratory failure; 4) the tumor involving the main airways; 5) often with localized disease at the initial presentation. This unusual presentation of ALCL may pose as a diagnostic pitfall and delay the treatment.