Lymphadenopathy with coexisting normal architecture in malignant lymphoma

Excerpt

A 5-year-old boy with left cervical lymphadenopathy was referred to our hospital for further examination. Given that ultrasonography of the left cervical lymph node showed hypoechoic, round findings and an echogenic hilus, the patient underwent open incisional biopsy from the left cervical lymph node. Unexpectedly, no malignant findings were detected by pathologic or flow cytometric analysis of the specimen apart from the abnormal karyotype of 47,XY,del(13)(q12q14),+rl in four of six cells detected by G-banding analysis. Since his left cervical lymph node continued to enlarge and subsequent positron emission/computed tomography (PET–CT) revealed enhanced FDG accumulation at the left cervical lymph nodes (maximum diameter 45 mm) and the right inguinal lymph node (maximum diameter 7 mm), the patient underwent re-biopsy of the left cervical lymph node 1 month after the initial procedure. Macroscopic and microscopic findings disclosed heterogeneous tissue architecture containing normal lymph node structures (Fig. 1a, b) and malignant lymphoma tissue (Fig. 1a, c). As immunostaining and flow cytometry of lymph node cells were positive for CD20, CD79a, CD45, and MIB-1, a diagnosis of stage III diffuse large B-cell lymphoma was made. G-banding analysis of lymph node in the second biopsy revealed the same abnormal karyotype of 47,XY,del(13)(q12q14),+rl in three of 16 cells. The patient commenced chemotherapy following the Japanese Pediatric Leukemia/Lymphoma Study Group B-NHL 03 protocol [1] for mature B-cell lymphoma and achieved complete remission after three courses of chemotherapy. The boy is presently healthy with no evidence of relapse 2 months after the last chemotherapy. …