Preliminary results of radiation dose escalation for locally advanced nasopharyngeal carcinoma.

PURPOSE: To study the safety and efficacy of dose escalation in tumor for locally advanced nasopharyngeal carcinoma (NPC). METHODS AND MATERIALS: From September 2000 to June 2004, 50 patients with T3-T4 NPC were treated with intensity-modulated radiotherapy (IMRT). Fourteen patients had Stage III and 36 patients had Stage IVA-IVB disease. The prescribed dose was 76 Gy to gross tumor volume (GTV), 70 Gy to planning target volume (PTV), and 72 Gy to enlarged neck nodes (GTVn). All doses were given in 35 fractions over 7 weeks. Thirty-four patients also had concurrent cisplatin and induction or adjuvant PF (cisplatin and 5-fluorouracil). RESULTS: The average mean dose achieved in GTV, GTVn, and PTV were 79.5 Gy, 75.3 Gy, and 74.6 Gy, respectively. The median follow-up was 25 months, with 4 recurrences: 2 locoregional and 2 distant failures. All patients with recurrence had IMRT alone without chemotherapy. The 2-year locoregional control rate, distant metastases-free and disease-free survivals were 95.7%, 94.2%, and 93.1%, respectively. One treatment-related death caused by adjuvant chemotherapy occurred. The 2-year overall survival was 92.1%. CONCLUSIONS: Dose escalation to 76 Gy in tumor is feasible with T3-T4 NPC and can be combined with chemotherapy. Initial results showed good local control and survival.

Concurrent and adjuvant chemotherapy for nasopharyngeal carcinoma: a factorial study.

PURPOSE: To study the efficacy of concurrent chemoradiotherapy (CRT) and adjuvant chemotherapy (AC) for nasopharyngeal carcinoma (NPC). PATIENTS AND METHODS: Patients with Ho's stage T3 or N2/N3 NPC or neck node > or = 4 cm were eligible. Patients were randomly assigned to have radiotherapy (RT) or CRT with uracil and tegafur and to have AC or no AC after RT/CRT. AC comprised alternating cisplatin, fluorouracil, vincristine, bleomycin, and methotrexate for six cycles. There were four treatment groups: A, RT; B, CRT; C, RT and AC; D, CRT and AC. For CRT versus RT, groups B and D were compared with groups A and C. For AC versus no AC, groups C and D were compared with groups A and B. RESULTS: Three-year failure-free survival (FFS) and overall survival (OS) for CRT versus RT were 69.3% versus 57.8% and 86.5% versus 76.8%, respectively (P =.14 and.06; n = 110 v 109). Distant metastases rate (DMR) was significantly reduced with CRT (14.8% v 29.4%; P =.026). Locoregional failure rates (LRFR) were similar (20% v 27.6%; P =.39). Three-year FFS and OS for AC versus no AC were 62.5% versus 65% and 80.4% versus 83.1%, respectively (P =.83 and.69; n = 111 v 108). DMR and LRFR were not reduced with AC (P =.34 and.15, respectively). Cox model showed CRT to be a favorable prognostic factor for OS (hazard ratio, 0.42; P =.009). CONCLUSION: An improvement in OS with CRT was observed but did not achieve statistical significance. The improvement seemed to be associated with a significant reduction in DMR. AC did not improve outcome.

Linear accelerator-based stereotactic radiosurgery for limited, locally persistent, and recurrent nasopharyngeal carcinoma: efficacy and complications.

PURPOSE: To evaluate the efficacy and complication of linear accelerator-based stereotactic radiosurgery (SRS) when used as salvage treatment for early-stage persistent and recurrent nasopharyngeal carcinoma (NPC) after primary radiotherapy (RT). MATERIALS AND METHODS: Between March 1998 and June 2001, 18 patients (15 men and 3 women; median age 46 years, range 32-84) with locally persistent or recurrent NPC confined to the nasopharynx (rT1) or with limited extension to the nasal fossa or parapharyngeal space (rT2) were treated by SRS. Thirteen patients had rT1 disease and 5 had rT2 disease. Most patients had disease not amenable to surgery or brachytherapy. All patients had undergone previous radical RT. Persistent disease was defined as tumor relapse within 4 months of completion of primary RT, and recurrence as tumor relapse beyond 4 months. Seven patients were treated for persistent disease, eight for a first recurrence, and three for a second recurrence. SRS was performed using multiple noncoplanar arcs of photons delivered to the target volume, which was defined by axial CT at a 3 mm thickness, supplemented by MRI in selected patients (67%). The median target volume was 5.3 cm(3) (range 2.2-16.9). The median SRS dose was 12.5 Gy (range 11-14) delivered to the 80% isodose line. All patients underwent serial nasopharyngoscopy and imaging after SRS. The median follow-up was 26 months (range 11-48). RESULTS: After SRS, 16 (89%) of 18 patients had complete regression of tumor as assessed by nasopharyngoscopy and biopsy. Four patients with an initial complete response to SRS subsequently developed local relapse again, with one recurrence developing outside the target volume 8 months after SRS and three within the target volume at 6-26 months after SRS. Two patients with local disease controlled by SRS developed relapse in other sites (neck node and liver metastases). The actuarial 2-year local control rate after SRS was 72%. Patients treated for persistent disease had a better local control rate (100%; 7 of 7) than those treated for recurrent disease (46%; 5 of 11). Patients with rT1 disease also had a better outcome after SRS compared with those with rT2 disease, with a control rate of 77% (10 of 13) for rT1 disease and 40% (2 of 5) for rT2 disease. Treatments were well tolerated, with no acute side effects. One patient had radiologic evidence of temporal lobe necrosis, although the right temporal lobe had already received a high dose during prior RT. That patient also developed additional local recurrence and liver metastases and died. The actuarial 2-year survival rate was 86%. CONCLUSIONS: Our preliminary results indicate that SRS is an effective treatment modality for persistent and recurrent early-stage NPC, with early control rates comparable to other salvage treatments such as brachytherapy and nasopharyngectomy. A modest SRS dose at 12.5 Gy also appears to be effective and is associated with minimal morbidities. More clinical experience and longer follow-up are needed to validate our results and to address fully the role of SRS in salvaging local failures of NPC.