Neoadjuvant or adjuvant therapy for resectable gastric cancer? A practice guideline

To make recommendations on the use of neoadjuvant or adjuvant therapy in addition to surgery in patients with resectable gastric cancer (T1-4, N1-2, M0).

Neoadjuvant or adjuvant treatments compared with "curative" surgery alone.

Overall survival, disease-free survival, and adverse effects.

The MEDLINE, CANCERLIT and Cochrane Library databases and relevant conference proceedings were searched to identify randomized trials.

Evidence was selected and reviewed by one member of the Cancer Care Ontario Practice Guidelines Initiative (CCOPGI) Gastrointestinal Cancer Disease Site Group and methodologists. A systematic review of the published literature was combined with a consensus process around the interpretation of the evidence in the context of conventional practice, to develop an evidence-based practice guideline. This report has been reviewed and approved by the Gastrointestinal Cancer Disease Site Group, comprising medical oncologists, radiation oncologists, surgeons, a pathologist and 2 community representatives.

When compared with surgery alone, at 3 years adjuvant chemoradiotherapy has been shown to increase overall survival by 9% (50% v. 41%, p = 0.005) and to improve relapse-free survival from 31% to 48% (p = 0.001). At 5 years, it has been shown to increase overall survival by 11.6% (40% v. 28.4%) and to improve relapse-free survival from 25% to 38% (p < 0.001). Treatment has been associated with toxic deaths in 1% of patients. The most frequent adverse effects (> grade 3 [Southwest Oncology Group toxicity scale] are hematologic (54%), gastrointestinal (33%), influenza-like (9%), infectious (6%) and neurologic (4%). The radiation fields used can possibly damage the left kidney, resulting in hypertension and other renal problems. Furthermore, this therapy could increase the demand on radiation resources. Physicians and patients should understand the tradeoffs between survival benefit and toxicity and cost before making treatment decisions.

After surgical resection, patients whose tumours have penetrated the muscularis propria or involve regional lymph nodes should be considered for adjuvant combined chemoradiotherapy. The current standard protocol consists of 1 cycle of 5-fluorouracil (5-FU) (425 mg/m2 daily) and leucovorin (20 mg/m2 daily) administered daily for 5 days, followed 1 month later by 45 Gy (1.8 Gy/d) of radiation given with 5-FU (400 mg/m2 daily) and leucovorin (20 mg/m2 daily) on days 1 through 4 and the last 3 days of radiation. One month after completion of radiation, 2 cycles of 5-FU (425 mg/m2 daily) and leucovorin (20 mg/m2 daily) in a daily regimen for 5 days are given at monthly intervals. There is no evidence on which to make a recommendation for patients with node-negative tumours that have not penetrated the muscularis propria. For patients unable to undergo radiation, adjuvant chemotherapy alone may be of benefit, particularly for those with lymph-node metastases. The optimal regimen remains to be defined. There is insufficient evidence from randomized trials to recommend neoadjuvant chemotherapy, or neoadjuvant or adjuvant radiotherapy or immunotherapy, either alone or in combination, outside a clinical trial.

A draft version of this document was circulated to 166 clinicians using a 21-item feedback questionnaire. Ninety-nine (63%) returned the questionnaire, and 74 of these indicated that the guideline was relevant to their clinical practice and completed the survey. Of the 74 clinicians, 52 (70%) agreed that the document should be approved as a practice guideline.

The CCOPGI is supported by Cancer Care Ontario and the Ontario Ministry of Health and Long-Term Care.