Primary biphasic lymphoplasmacytic lymphoma of the lung. A mucosa-associated lymphoid tissue lymphoma with compartmentalization of plasma cells in the lung and lymph nodes

The solitary pulmonary nodule: a primer on differential diagnosis

Despite significant advances in noninvasive imaging techniques, management of the solitary pulmonary nodule (SPN) remains a challenge for chest physicians. Patients with SPNs are frequently asymptomatic, and the physical examination is seldom revealing. Accurate diagnosis is essential, because >50% of patients will require prompt disease-specific therapy. The complexity of the problem is best appreciated by reviewing the differential list, which includes nearly 80 distinct clinical entities. Consequently, a thorough understanding of the more common etiologies is necessary to adequately treat patients with SPNs.

Diagnosis of an anemone cell tumor as a B-cell lymphoma by molecular analysis

An 83-year-old man presented with mediastinal and axillary lymphadenopathy. Immunophenotyping and electron microscopy performed on an excision biopsy were inconclusive. On a repeat biopsy a year later the ultrastructural features typical of an anemone cell tumor were seen. A panel of monoclonal antibodies showed positivity for vimentin only. The diagnosis of a high-grade B-cell lymphoma could be made only after detection of immunoglobulin gene rearrangement by polymerase chain reaction gene amplification.