Researchers from Germany conducted two studies, in which they investigated the characteristics and management of patients with primary gastrointestinal non-Hodgkin's lymphomas (PGI NHL), between 1992 and 1996.
In the first, they obtained epidemiologic data and information on anatomic and histologic distribution, clinical features, and treatment results in 371 patients with PGI NHL.
Radiotherapy and chemotherapy were stratified according to histologic grading, stage, and whether surgery had been carried out or not.
Of the patients, 75% had gastric NHL. Within the intestine, the small bowel and the ileocecal region were involved in 9% and 7% of the cases, respectively. Multiple GI involvement was 6.5%.
Approximately 90% of the GI NHL were in stages IE/IIE.
Aggressive NHL accounted for the majority, with a distinguishable pattern in several sites.
40% of PGL were of low-grade mucosa-associated lymphatic tissue type. One third of large-cell lymphomas had low-grade components. Most intestinal NHL were germinal-center lymphomas.
In gastric and ileocecal lymphoma, event-free and overall survival were significantly higher, as compared with the small intestine or multiple GI involvement.
In PGL, localized disease was prognostic for both event-free and overall survival. However, histologic grade only influenced event-free survival significantly.
The authors commented that PGI NHL are heterogeneous diseases. The number of localized PGL allowed the investigators to conduct detailed analyses, although larger studies are needed for stages III and IV, and for intestinal NHL.
A uniform reporting system for PGI NHL, in terms of definitions, and histologic and staging classifications, is needed to facilitate comparison of treatment results, they concluded.
|5-year survival rates after PGI NHL treatment:|
Conservative treatment 84%
Conservative treatment plus surgery 85%
|Journal of Clinical Oncology|
In the second study, the team focused on the combined surgical and conservative treatment (CSCT) versus conservative treatment (CT) alone for localized gastric lymphoma.
Patients with low-grade PGL were treated with extended-field (EF) radiotherapy (30 Gy).
In case of residual tumor after surgery or in case of CT only (in stage IIE after 6 cycles of cyclophosphamide, vincristine, and prednisone), an additional boost of 10 Gy was given.
All patients with high-grade PGL were treated with 4 (stage IE) or 6 (stage IIE) cycles of cyclophosphamide, doxorubicin, vincristine, and prednisone. This was followed by EF radiotherapy (stage IE) or involved-field (IF) radiotherapy (stage IIE).
Radiotherapy dosage corresponded to low-grade NHL.
A total of 106 patients had CT only. The survival rate after 5 years was found to be 84%. It was influenced neither by patients' characteristics nor by stage or histologic grade.
Some 79 patients had CSCT. Their survival rate was 82%.
The team found that complete resection of the tumor was prognostic for the overall survival, as compared with incomplete resection.
Dr Peter Koch, of Münster, Germany, concluded on behalf of the group, "Although the study was not randomized, a stomach-conserving approach may be favored."