Source: DGNews  |  Posted 2 years ago

By Wayne Kuznar

PHOENIX, Ariz -- March 10, 2009 -- Adjuvant chemoradiation provides no survival benefit to patients with gastric cancer who are treated with gastrectomy and D2-lymphadenectomy (nodal dissection to the N2 level), researchers stated here at the Society of Surgical Oncology (SSO) 62nd Annual Cancer Symposium.

Chemoradiation had previously been shown by Macdonald and colleagues (N Engl J Med. 2001;345:725-730) to improve the overall and disease-free survival of surgical treatment for gastric cancer, but this improvement was not observed in the small group in which a D2-lymphadenectomy was performed, said lead investigator Felipe Coimbra, MD, Hospital do Câncer A.C. Camargo, São Paulo, Brazil, speaking here at a poster session on March 7.

The finding was derived from a retrospective chart review of patients treated with gastrectomy for gastric cancer at a single hospital in Brazil. The outcome was confirmed by the same authors in another study in which the Maruyama Index was used to compare the effectiveness of the strategies. (The Maruyama Index is a quantitative estimate of residual nodal disease after gastric cancer surgery.)

In the current study, clinical and pathologic data were collected from the charts of 116 patients treated with gastrectomy for gastric cancer between September 1998 and October 2006. Eighty patients were treated with surgery exclusively, while 36 patients underwent chemoradiation according to the same scheme utilised in the Macdonald study. The Macdonald scheme of adjuvant treatment consisted of fluorouracil 425 mg/m²/day, plus leucovorin 20 mg/m²/day, for 5 days, followed by 4,500 cGy of radiation at 180 cGy/day, given 5 days per week for 5 weeks, with modified doses of fluorouracil and leucovorin on the first 4 and the last 3 days of radiotherapy. One month after the completion of radiotherapy, two 5-day cycles of fluorouracil plus leucovorin were given 1 month apart.

Of the group that received adjuvant chemoradiotherapy, 82% completed the adjuvant treatment, and 3 patients died related to the adjuvant therapy.

Median follow-up was 46 months.

"We found no differences in overall survival, disease-free survival, types of recurrence, and cancer-specific survival between these 2 groups of patients," concluded Dr. Coimbra.

The recurrence rates were 31% in the group treated with surgery only compared with 25.7% in those patients treated with adjuvant chemoradiation (P = .549). Regional recurrence was 8.8% in the surgery group and 2.8% in the group receiving adjuvant treatment (P = .516).

Disease-free survival was a median of 37.2 months in the surgery-only group, and 16% in the adjuvant-therapy group (P = .540). Overall survival was a median of 39 months in the surgery-only group and 21 months in the adjuvant-therapy group (P = .594).

The 5-year disease-free survival rates were 62.3% with surgery only and 66% with adjuvant chemoradiation; the 5-year overall survival rates were 51.5% in the surgery-only group and 56.1% in the adjuvant-treatment group.

The 5-year cancer-specific survival was 63% with surgery only and 62.4% with adjuvant chemoradiation.

"Even when we compared only the node-positive patients, there was no statistical difference [in outcomes] between the 2 groups," said Dr. Coimbra.

He continued, "We think the patient needs good locoregional surgical treatment. If you have good locoregional surgery with removal of all the lymph nodes that might be positive, we have the same effect on survival as the Macdonald scheme in patients without a good lymphadenectomy."

[Presentation title: Does Adjuvant Chemoradiation Treatment Improve Survival in Patients Treated With Gastrectomy and D2-Lymphadenectomy for Gastric Cancer? Abstract P167]