The Pattern of Residual Tumor After Neoadjuvant Chemotherapy for Locally Advanced Esophageal Cancer and Its Clinical Significance :

Patients with esophageal carcinoma receiving postoperative chemotherapy showed superior disease-free survival than those receiving surgery alone in a Japan Clinical Oncology Group trial (JCOG9204). The purpose of this study was to evaluate optimal perioperative timing-that is, before or after surgery-for providing chemotherapy in patients with locally advanced esophageal squamous cell carcinoma. Eligible patients with clinical stage II or III, excluding T4, squamous cell carcinoma were randomized to undergo surgery followed (group 1) or preceded (group 2) by chemotherapy consisting of two courses of cisplatin plus 5-fluorouracil. The primary end point was progression-free survival. We randomized 330 patients, with 166 assigned to group 1 and 164 to group 2, between May 2000 and May 2006. The planned interim analysis was conducted after completion of patient accrual. Progression-free survival did not reach the stopping boundary, but overall survival in group 2 was superior to that of group 1 (P = 0.01). Therefore, the Data and Safety Monitoring Committee recommended early publication. Updated analyses showed the 5-year overall survival to be 43% in group 1 and 55% in group 2 (hazard ratio 0.73, 95% confidence interval 0.54-0.99, P = 0.04), where the median follow-up of censored patients was 61.6 months. Concerning operative morbidity, renal dysfunction after surgery in group 2 was slightly higher than in group 1. Preoperative chemotherapy with cisplatin plus 5-fluorouracil can be regarded as standard treatment for patients with stage II/III squamous cell carcinoma.

Cancer drug resistance is a major problem, with the majority of patients with metastatic disease ultimately developing multidrug resistance and succumbing to their disease. Our understanding of molecular events underpinning treatment failure has been enhanced by new genomic technologies and pre-clinical studies. Intratumour genetic heterogeneity (ITH) is a prominent contributor to therapeutic failure, and it is becoming increasingly apparent that individual tumours may achieve resistance via multiple routes simultaneously - termed polyclonal resistance. Efforts to target single resistance mechanisms to overcome therapeutic failure may therefore yield only limited success. Clinical studies with sequential analysis of tumour material are needed to enhance our understanding of inter-clonal functional relationships and tumour evolution during therapy, and to improve drug development strategies in cancer medicine.

In patients with locoregional carcinoma of the esophagus or esophagogastric junction who underwent preoperative chemoradiation, it is unclear whether survival was better predicted by pretherapy clinical stage or by posttherapy pathologic stage. The authors studied 235 consecutive patients with pretherapy clinical Stage II, III, or IVA (according to American Joint Committee on Cancer criteria) carcinoma of the esophagus or esophagogastric junction who were treated with chemoradiation followed by esophagectomy. Posttherapy cancer status was classified using pathologic stage and semiquantitative assessment of residual carcinoma. Clinicopathologic features, residual carcinoma status, and pretherapy and posttherapy stage were compared with disease-free and overall survival. Posttherapy pathologic stage was Stage 0 in 29% of patients, Stage I in 11% of patients, Stage II in 34% of patients, Stage III in 20% of patients, and Stage IV in 6% of patients. Cancer downstaging occurred in 56% of patients. In univariate analysis, disease-free and overall survival were predicted by posttherapy pathologic stage (both with P < 0.001), margin status (P = 0.002 and P = 0.01, respectively), extent of residual carcinoma (both with P < 0.001), and downstaging (both with P = 0.001), but not by age, gender, type of cancer, pretherapy clinical stage, or preoperative regimen. However, in multivariate analysis, disease-free and overall survival were independently predicted by posttherapy pathologic stage (both with P = 0.02). Extent of residual carcinoma was a marginally significant predictor of overall survival (P = 0.04). Posttherapy pathologic stage was the best available predictor of outcome for patients with locoregional carcinoma of the esophagus or esophagogastric junction who underwent chemoradiation therapy followed by esophagectomy. The findings in the current study supported the concept of downstaging by preoperative therapy. Copyright 2005 American Cancer Society.