Tuberculous granulomatous lymphadenitis in patients receiving imatinib mesylate (Glivec) for metastatic gastrointestinal stromal tumor

Abstract

Background: Imatinib mesylate (IM) is the standard treatment for BCR-ABL-positive chronic myelogenous leukemia (CML) and is the first-line adjuvant and palliative treatment for metastatic and inoperable gastrointestinal stromal tumor (GIST). IM is not known to be associated with an increased risk for development of granulomatous diseases. Methods: We describe our experience with 2 patients (42 and 62 years of age) who developed granuloma-tous disease during IM treatment for metastatic GIST. Results: Mean duration of IM treatment was 12 (range 8-16) months. Enlarged lymph nodes with increased metabolism on FDG-PET-CT examination were detected and resected. Affected sites were supraclavicular (1) and subcarinal/mediastinal (1) lymph nodes. Histological examination revealed caseating and non-caseating granulomas suggestive of tuberculosis and sarcoidosis, respectively. Mycobacterium tuberculosis was detected by PCR in lymph nodes of 1 patient who was then successfully treated by anti-tuberculous agents. The other patient had negative sputum test for acid-fast bacilli and PCR-DNA-analysis was negative for M. tuberculosis and other mycobacteria. He received no anti-tuberculous therapy and had no evidence of progressive lymphadenopathy or new lung lesions during follow-up. Conclusion: Our observations underline the necessity to obtain biopsy material from enlarged or metabolically active lymph nodes developing during IM treatment for timely diagnosis and appropriate treatment.