Purpose: To evaluate the toxicity and efficacy of concomitant chemoirradiation (CRT) followed by adjuvant chemotherapy compared with radiotherapy (RT) alone in Chinese patients with locoregionally advanced nasopharyngeal carcinoma (NPC).
Methods and materials: Between March 1997 and September 2000, 47 Chinese patients with Stage III (n = 9, 19%) and IV (n = 38, 81%) NPC were treated with by CRT using cisplatin 100 mg/m(2) on Days 1, 22, and 43 of RT, plus adjuvant chemotherapy using cisplatin 80 mg/m(2) for 1 day and 5-fluorouracil 1 g/m(2) for 4 days on Days 71, 99, and 127. These patients were then compared with a cohort of 47 patients treated between 1990 and 1993 with RT alone, who were matched with respect to T stage, N stage, nodal bilaterality, nodal level, and nodal size. The RT techniques were similar in the two groups but different dose and fractionation schemes were used. The median biologic equivalent dose to 2 Gy per fraction delivered to the nasopharynx was 68 Gy in the CRT group and 65.3 Gy in the RT-alone group.
Results: The compliance rates were 62% for concomitant chemotherapy and 40% for adjuvant chemotherapy. No treatment-related deaths occurred. At the end of treatment, 96% of the CRT group and 79% of the RT-alone group achieved a complete response (p = 0.013). With a median follow-up of 26 months, the 3-year relapse-free survival, disease-specific survival, overall survival, local relapse-free survival, nodal relapse-free survival, and distant metastasis-free survival rate for the CRT group and the RT-alone group was 62% vs. 44% (p = 0.048), 67% vs. 71% (p = 0.88), 65% vs. 69% (p = 0.93), 87% vs. 75% (p = 0.059), 95% vs. 80% (p = 0.026), and 75% vs. 70% (p = 0.84), respectively.
Conclusion: Our experience indicates that concomitant CRT improves locoregional control in Chinese patients with locoregionally advanced NPC, but our analyses failed to detect any impact on distant failure and survival. The failure to reduce distant metastasis and improve survival may have related in part to the more advanced disease stage in our patients and the relatively low compliance rate of adjuvant chemotherapy. Our findings suggest caution should be exercised in extrapolating the findings of the Intergroup Study 0099 to Chinese patients, and confirmatory results from prospective randomized studies in the endemic population are needed.