Background/aims: Primary gastric lymphoma is a relatively rare disease. As the concept of MALT (mucosa-associated lymphoid tissue) lymphoma has been acknowledged, a relation between primary gastric lymphoma and Helicobacter pylori infection seems apparent, appropriate treatment, including surgical resection, and/or chemotherapy, and/or radiotherapy has remained controversial.
Methodology: Between 1974 and 1996, we treated 85 Japanese patients with histologically proven primary gastric lymphomas (stage I and II according to modified Ann Arbor staging) with surgery, and/or adjuvant chemotherapy. The clinicopathological factors, especially regarding surgical curability and survival were evaluated retrospectively.
Results: Of the 85 patients (44 men, and 41 women), average age was 60.5 years. The lesion was frequently located at the middle third of the stomach, and multiple lesions were noted in 19 patients. Microscopic lymph node metastasis was positive in 37.6% (32/85), and the rate of positive metastasis increased in proportion to depth of invasion. There was a discrepancy between macro- and microscopic findings regarding lymph node metastasis. Total gastrectomy was done for 50 patients, distal gastrectomy for 31, pancreatoduodenectomy for 3, and gastrojejunostomy for 1 patient. Lymph node dissection was done at the D1,2 level for 73, and at the D3 level for 12 patients. There were no major complications except in 3 cases (subphrenic abscess), and there was 1 operative death. The overall 5-year survival and 10-year survival was 82.3% and 74.0%, respectively. In the stage I patients, the 5-year and 10-year survival rate was 97.5%, respectively. All cases of surgery were curative, and surgery alone resulted in the same survival time as the surgery plus chemotherapy group (10-year survival; 100% vs. 96.6%, no statistical difference). In the stage II patients, 5-year and 10-year survival rates were 58.6% and 44.2%, respectively. Surgery was curative in 59.3% (19/32), and palliative in 40.7% (13/32). Palliative surgery was done because of extensive lymph node metastasis in 6 patients, invasion to adjacent organ in 6, and both in 1 patient. Chemotherapy was prescribed in 71.9% of the patients (23/32), and when compared with the patients who were on chemotherapy, the survival rate showed no statistical difference regardless of palliative or curative surgery.
Conclusions: Surgery for primary gastric lymphoma had low complication rate, and led to good survival rate in stage I disease. In stage II disease, surgical curability did not affect the survival, implying the necessity of the evaluation about the treatment strategy by randomized study. However, considering the stage migration before and after and possible inaccuracy of preoperative staging, the application of non-surgical treatment must be prudent.