Nuclear DNA content and its prognostic value in lymphoma of the stomach.

Nuclear DNA content of 27 primary lymphomas of the stomach was determined by flow cytometry from paraffin-embedded tissue. Thirteen (50%) of the 26 non-Hodgkin's lymphomas were aneuploid. The only case with Hodgkin's disease was diploid. The mean age of patients with aneuploid lymphoma was less than that of patients with diploid lymphoma (53 years versus 63 years, P = 0.02). DNA aneuploidy was more common in tumors with extragastric spread into the adjacent organs or the upper abdominal lymph nodes than in intragastric lymphomas (73% versus 17%; P = 0.003). Patients with aneuploid lymphoma had both inferior crude recurrence-free survival rate (P = 0.05) and survival rate corrected for known intercurrent diseases (P = 0.02) than patients with diploid lymphoma. Extragastric spread of lymphoma into the adjacent organs or the upper abdominal lymph nodes was, however, the most important prognostic factor by a multivariate analysis.