EBV-associated gastric diffuse large B-cell lymphomas might be resistant to standard chemoradiotherapy

10-11-2006

"Primary gastric diffuse large B-cell lymphomas are generally well controlled by non-surgical treatment with combination chemotherapy followed by radiotherapy. We have previously reported that over 90% of patients achieved complete response (CR) with this therapeutic strategy: three cycles of cyclophosphamide, adriamycin, vincristine and prednisone followed by radiotherapy (40.5 Gy)," scientists in Japan reported.

"Although the CR rate was very high, some patients still showed resistance to this combination therapy. In order to clarify the factors related to therapy resistance, we examined the relationship between EBV, which was examined using an in situ hybridization technique, and the patients' clinical courses," explained T. Yoshino and colleagues, Okayama University.

"Out of the 50 patients, 4 were EBV positive; over half of lymphoma cells were positive for EBV by in situ hybridization. Of the 3 EBV-positive patients, 2 showed progressive disease and 1 achieved partial response (PR). Two of the patients died of disease progression. The other patient achieved CR, but the lymphoma recurred with distant metastasis in the cerebellum 3 months after remission.

"In the present study, 8 patients did not achieve CR or they relapsed, 4 patients showed progressive disease, 1 patient achieved PR, and 3 patients achieved CR with recurrence. Therefore, half of these unfavorable patients were EBV positive," informed the investigators.

The researchers concluded, "This finding strongly indicated that EBV-associated gastric diffuse large B-cell lymphomas frequently show resistance to standard chemoradiotherapy, although some other adverse factors remain unclear."

Yoshino and colleagues published their study in Cancer Science (Epstein-Barr virus involvement is a predictive factor for the resistance to chemoradiotherapy of gastric diffuse large B-cell lymphoma. Cancer Sci, 2006;97(2):163-166).

For additional information, contact T. Yoshino, Okayama University, Graduate School of Medicine Dent. & Pharmaceutical Science, Dept. Pathology, 2-5-1 Shikata Cho, Okayama 7008558, Japan.