Accelerated concomitant boost radiotherapy and chemotherapy for advanced nasopharyngeal carcinoma

Role of endocavitary brachytherapy with or without chemotherapy in cancer of the nasopharynx

PURPOSE

We previously reported our preliminary experience with nasopharyngeal cancer boosted after 60-70 Gy external beam radiotherapy (EBRT) by fractionated endocavitary brachytherapy (ECBT) to cumulative doses of 78-82 Gy. As for Stage III-IVB disease, cisplatin (CDDP)-based neoadjuvant chemotherapy (CHT) was given. The aim of the present study was to define the role of ECBT more accurately.

METHODS AND MATERIALS

Ninety-one patients with primary nasopharyngeal cancer, staged according to the 1997 UICC/AJCC classification system, were treated between 1991 and 2000 with 60-70 Gy external beam radiotherapy and 11-18 Gy ECBT. Of the 91 patients, 21 were treated in conjunction with CHT and 70 without CHT. Tumors were subdivided into undifferentiated (UD) and well, moderately, and poorly differentiated (WMP-D) subtypes. Treatment results were analyzed for local control (LC), disease-free survival (DFS), freedom from distant metastasis, and overall survival (OS).

RESULTS

A univariate and multivariate Cox regression analysis found stage, treatment period, age, and grade significant for LC, DFS, and OS. At 2 years, for Stage I-IIB (1st period, 1991-1996), the LC, DFS, and OS were 96%, 88%, and 80%, respectively, vs. 65%, 46%, and 52% for Stage III-IVB. For the 2nd treatment period (1996-2000; CHT for Stage III-IVB), the LC, DFS, and OS at 2 years was 100%, 90%, and 61% (Stage I-IIB), respectively, vs. 86%, 74%, and 66% (Stage III-IVB). Three prognostic groups (PGs) were constructed. For the 1991-1996 period, at 2 years, patients in the good PG (UD Stage I-IIB disease) had 100% LC and 92% OS; those in the intermediate PG (UD Stage III-IVB or WMP-D Stage I-IIB), had 94% LC and 71% OS; and those in the poor PG (WMP-D Stage III-IVB) had 47% LC and 40% OS. For the 1996-2000 period, at 2 years, the good PG had 100% LC and 88% OS; the intermediate PG had 100% LC and 64% OS; and the poor PG had 71% LC and 60% OS.

CONCLUSION

For Stage I-IIB disease treated between 1991 and 2000, at 3 years, the LC and OS was 97% and 67%, respectively. The results with 77-81 Gy without CHT warrant EBRT combined with ECBT to remain our standard of care for Stage I-IIB disease. For N2-3 and/or T3-4 tumors, in addition to high doses of RT, neoadjuvant CHT was administered as of 1996. For the 1991-2000 period, at 3 years, the LC was 86% and the OS was 72% with CHT, with little extra morbidity; they were 68% and 35% without CHT. Because of better target coverage and sparing, T3-4 tumors are currently boosted by stereotactic RT to 81.2 Gy.

Nasopharyngeal carcinoma

Nasopharyngeal carcinoma is usually present as locally advanced (stage III or IV) disease. Before 1980, the primary treatment was radiotherapy. The 5-year survival rate of patients with stage IVM0 across the world was less than 30%. Local, regional, and systemic recurrences are high in these patients and contributed to the poor survival. Sequential chemotherapy followed by radiotherapy (especially with the combination of cisplatin and 5-fluorouracil infusion for three courses) resulted in a 5-year survival rate of up to 55% in patients with stage IV disease. Concurrent single-agent cisplatin and radiotherapy improved 5-year survival rate to up to 55% in these patients. Total treatment with concurrent chemoradiotherapy followed by adjuvant cisplatin and 5-fluorouracil infusion resulted in 5-year survival rate of approximately 75%. Reversing the sequence of treatment by giving chemotherapy followed by concurrent chemoradiotherapy may improve the 5-year survival to up to 90%. In patients with recurrent disease or systemic metastases, the chances of salvage and long remission (many years) is approximately 15% to 20% with the use of adequate and effective chemotherapy. Newer agents, alone or concomitant with radiotherapy, are being evaluated in these patients.

Chemoradiation schedules--what radiotherapy?

Synchronous chemoradiation (SCRT) is playing an increasing role in the primary and multimodality management of cancer in many disease sites. Current schedules have been in the main empirically derived, and the addition of chemotherapy has in some cases led to a compromise in the total dose or scheduling of radiotherapy. Non-randomised phase II studies abound, but there are few well designed phase III randomised studies with comprehensive acute toxicity data and mature follow-up. In many sites long-term survival is unusual. So severe morbidity and long term functional outcome is poorly documented. It is therefore difficult to assess the real benefit of SCRT. This review uses the endpoints of local control and overall survival from randomised trials in small and non-small cell lung cancer, head and neck cancer, oesophageal cancer, rectal and anal cancer. We explore the evidence for total dose; fractionation; fraction size; the effects of a gap in treatment; and scheduling of radiation in SCRT.

CONCLUSIONS

An optimal schedule of SCRT has not yet been derived. The enhanced acute toxicity and persistent high risk of local failure in many disease settings with current SCRT schedules demand that more effective and less toxic treatment strategies must be identified in the future. These schedules should be tested in randomised trials with the emphasis on meticulous reporting of acute toxicity endpoint and documenting the field sizes or proportions of critical organs within the high dose area if we are to derive the optimal therapeutic ratio.

Chemotherapy and high–dose-rate brachytherapy in the management of advanced cancers of the nasopharynx

PURPOSE

The aim of this study was to calculate the costs of chemotherapy and high-dose-rate brachytherapy in advanced-stage nasopharyngeal cancer. It is argued whether the effect of chemotherapy and this type of high-dose, high-precision radiation therapy is worth the costs.

METHODS AND MATERIALS

Clinical results of Stage III-IVB nasopharyngeal cancer in patients treated between 1991 and 2000 are reported. Treatment was broken down into five categories: workup, chemotherapy, preparation of radiation therapy, and application of radiation. For each category, costs were computed. Nasopharyngeal cancer treatment costs were compared with costs previously reported on patients treated for cancers of the oral cavity, larynx, and oropharynx.

RESULTS

With the addition of neoadjuvant chemotherapy and high cumulative doses of radiation (77-81 Gy) with brachytherapy, disease-free survival increased from 48% to 74% (p=0.002), and overall survival increased from 35% to 72% (p=0.005). The Rotterdam protocol has been implemented stepwise: as of 1991, costs per patient increased from 4521 Euros (US$5023; 2001 exchange rate [December]: 1 Euro approximately 0.88 US$) for conventional external beam radiation therapy to 13,728 Euros (US$15,253) in 2000 for combinations of chemotherapy, conventional external beam radiation therapy, and brachytherapy. In case of stereotactic radiotherapy, the cost was 14,516 Euros (US$16,495).

CONCLUSIONS

Costs for cancer in the nasopharynx vary from 14,528 Euros (US$16,509) to 15,316 Euros (US$17,405) in case of brachytherapy and stereotactic radiotherapy, respectively, if follow-up costs are added. The treatment cost for other head and neck sites was 21,858 Euros (US$24,126). Given the improvement in survival, the sparing capabilities of current high-dose, high-precision radiotherapy techniques, and the favorable cost profile compared with other sites, it is argued that costs should not be considered prohibitive for the introduction of chemotherapy and high-technology-based radiotherapy in advanced nasopharyngeal cancer.