Precursor B- or T-lymphoblastic lymphoma presenting with cutaneous involvement: a series of 13 cases including 7 cases of cutaneous T-lymphoblastic lymphoma.

Background: Lymphoblastic lymphoma (LBL) is a rare neoplasm of precursor lymphocytes, and cutaneous involvement is present in less than 20% of cases.

Objective: We sought to describe the clinical and histopathological features of cutaneous LBL.

Methods: We retrospectively examined the clinical and histologic features of 13 patients with cutaneous LBL, 6 with B-LBL and 7 with T-LBL.

Results: Five of 6 patients with B-LBL had lesions in the head and neck area, whereas 4 of 7 patients with T-LBL developed skin lesions on sites other than the head and neck. Seven patients (1 case of B-LBL, and 6 of 7 cases of T-LBL) developed multiple skin lesions, and the T-LBL cases frequently developed multiple skin lesions in the head, neck, and throughout the torso. Complete remission was achieved in 9 patients (3 patients with T-LBL and all patients with B-LBL).

Limitations: This study used a retrospective design and included a small sample size.

Conclusion: This study compared the clinical features of T-LBL and B-LBL, in particular the affected sites and number of skin lesions. Cutaneous T-LBL is likely to be accompanied by disseminated disease and has a relatively poor prognosis compared with B-LBL.