Relationship between the response to treatment and the prognosis of patients with aggressive lymphomas treated with chemotherapy followed by involved-field radiotherapy: Radiographic assessment

Objective: We examined the relationship between the response to treatment and prognosis of patients with aggressive lymphoma. Methods: We reviewed 33 patients with aggressive lymphoma treated with chemotherapy consisting of the CHOP regimen followed by radiotherapy. Twelve patients had Stage I, 13 had Stage II, 6 had Stage III and 2 had Stage IV disease. According to the International Prognostic Index (IPI), 13 had low, 15 had low-intermediate, 2 had high-intermediate and 3 had high IPI. After three to six cycles of chemotherapy, involved-field radiotherapy was performed. We evaluated the response to treatment by computed tomography (CT), magnetic resonance imaging (MRI) and gallium scintigraphy (Ga-67) at the time of completion of chemotherapy and at the time of completion of radiation therapy. The median follow-up period was 48 months (4-80). Results: The 2-year progression-free survival rates of the patients with Ga-67 positive uptake and Ga-67 negative uptake after completion of chemotherapy were 78 and 26% (P = 0.009), respectively. However, there were no statistically significant correlations between progression-free survival and the response after completion of chemotherapy determined by CT (P = 0.75) or MRI (P = 0.19). The response to treatment at the time of completion of overall treatment was not useful for prediction of prognosis. Conclusions: Ga-67 positive uptake at the completion of chemotherapy before radiotherapy may be associated with poor prognosis.