Hepatic dysfunction after radiotherapy for primary gastric lymphoma

Patients with primary gastric lymphoma (PGL) are often treated with three-dimensional conformal radiotherapy (3D-CRT) in three to four fields to reduce the dose to the left kidney. However, the liver dose is higher than conventional parallel-opposed fields. This study was designed to evaluate hepatic dysfunction after 3D-CRT in patients with PGL. The data of 20 PGL patients treated with 3D-CRT were analyzed. Of the 20 patients, 3 had mucosa-associated lymphoid tissue (MALT) lymphoma and 17 had diffuse large B-cell lymphoma (DLBCL). The median dose used to treat MALT lymphoma was 30 Gy and 40 Gy for DLBCL. Pretreatment and post-treatment transaminase and alkaline phosphatase (ALP) values were compared. Radiation-induced hepatic dysfunction (RIHD) was defined as a more than 2-fold increase in transaminase or ALP levels, exceeding the upper limit within 4 months of the completion of radiotherapy. Increased transaminase or ALP levels were observed in 19 patients (95%). RIHD was observed in 14 patients (70%). The transaminase and ALP values were significantly different between pretreatment and post-treatment. There were significant differences in liver volumes receiving ≥5, ≥10, ≥15 and ≥20 Gy (V5, V10, V15 and V20) and in the mean liver doses between patients with and without RIHD. For patients with V10 > 60%, V15 > 50% or V20 > 30% in particular, the incidence rates of RIHD were significantly high. After radiotherapy for PGL, hepatic dysfunction occurred at a high rate. Thus, radiotherapy treatment should be planned in order to reduce liver doses.