Clinical features and treatment outcomes of limited-stage mantle cell lymphoma: Consortium for Improving Survival of Lymphoma report.

Limited-stage (Ann Arbor stage I or II) mantle cell lymphoma (MCL) is an extremely rare disease. Thus, there is little data on the clinical features and treatment outcomes of patients with early-stage MCL. We examined consecutive stage I or II MCL 41 cases diagnosed between 2000 and 2016 in 16 institutions of the Consortium for Improving Survival of Lymphoma group. All cases were pathologically confirmed and systemic evaluation was performed for staging. The clinical features were reviewed, and the treatment outcomes were analyzed. The median age of patients was 66 years (range 19-85 years); there were more men (n = 31, 75.6%) than women. Most patients (n = 28, 68.3%) had stage 2 disease, and 29 (70.7%) were symptomatic. The elevation of lactate dehydrogenase (n = 2, 4.9%) was not common; thus, 39 patients (95.1%) had a low-risk score (0 or 1) for the International Prognostic Index, and 28 (68.3%) had a low-risk score (1-3) for the MCL International Prognostic Index. Most patients (n = 37, 90.1%) received chemotherapy as the first therapeutic strategy, while some received radiotherapy (n = 2), surgical resection (n = 1), or no treatment (n = 1). Of the patients who received chemotherapy, 23 (56.9%) received a rituximab-containing regimen, and R-CHOP (n = 17) and R-bendamustine (n = 5) were commonly used. The best response was noted in 97.4% (n = 38) of patients, including 32 who showed a complete response (78%). With a median follow-up duration of 40.6 months, the 42 months relapse-free survival was 59.1%, and the 5-year overall survival rate was 80.4%. Limited-state MCL showed indolent clinical and low-risk prognostic features. Chemotherapy could be effective for controlling localized MCL lesions, with high complete response rates.