Pure infradiaphragmatic Hodgkin's lymphoma. Clinical features, prognostic factor and comparison with supradiaphragmatic disease.

Background And Objectives: Pure infradiaphragmatic Hodgkin's lymphoma (HL) is a rare disease. The prognostic impact of a purely infradiaphragmatic localization of this lymphoma is controversial. We aimed to evaluate the baseline clinicopathologic features, prognostic factors and outcome of a large series of consecutive patients with pure infradiaphragmatic HL.

Design And Methods: We analyzed 131 patients with clinical stage I/II infradiaphragmatic HL treated with ABVD or equivalent regimens with or without radiotherapy, and compared 54 of them with 444 patients with pure supradiaphragmatic disease, who were treated at the same center.

Results: Older age, clinical stage II (borderline), involvement of > or =3 sites, lymphocyte predominant histology, elevated serum beta2-microglobulin and higher International Prognostic Score were more frequent in patients with infradiaphragmatic disease than in those with supradiaphragmatic disease, while nodular sclerosis was less frequent. The complete remission rate was 100%, 97% and 82% for stages I, IIA and IIB, respectively. Only B-symptoms independently predicted for inferior failure-free survival, while inferior overall survival was independently associated with the involvement of > or =3 sites. At 10 years failure-free survival was 82+/-6% (vs. 85+/-2% for patients with supradiaphragmatic disease, p=0.45), overall survival was 74+/-8% (vs. 91+/-2%, p=0.0006), and disease-specific survival 87+/-5% (vs. 94+/-1%, p=0.04). In multivariate analysis the differences between infradiaphragmatic and supradiaphragmatic disease were obscured by older age and B-symptoms.

Interpretation And Conclusions: Pure infradiaphragmatic HL presents with distinct clinicopathologic characteristics. The previously reported poorer outcome may be explained by the unfavorable profile of the patients rather than the infradiaphragmatic presentation per se. Patients with stage IIB disease should probably be classified as having advanced HL because of the unacceptable rate of primary refractory disease.