Results and prognostic factors in the retreatment of locally recurrent nasopharyngeal carcinoma.

PURPOSE

To review the results and evaluate the prognostic factors in the retreatment of locally recurrent nasopharyngeal carcinoma.

METHODS AND MATERIALS

We reviewed the records of 74 patients with locally recurrent nasopharyngeal carcinoma treated at the University of California, San Francisco between 1957 and 1995. The histologic types included squamous cell carcinoma in 6 (8.1%), nonkeratinizing carcinoma in 48 (64.9%), and undifferentiated carcinoma in 20 (27%) cases. The site of recurrence was in the primary in 46 (62.2%), in the neck nodes in 20 (27%), and in both sites in 8 (10.8%) patients. The recurrent disease was Stage I in 10 (13.5%), Stage II in 16 (21.6%), Stage III in 20 (27%), and Stage IV in 28 (37.9%) patients. Thirty-seven (50%) patients developed recurrence within 2 years and 58 (78.4%) within 5 years after initial treatment. Radiotherapeutic techniques used in the retreatment of primary recurrence consisted of external beam radiotherapy (EBRT), intracavitary brachytherapy, heavy-charged particle beam, and gamma knife, alone or in combination. Reirradiation doses ranged from 18 to 108 Gy, with a median dose of 60 Gy. Treatment of recurrent neck nodes consisted of radical neck dissection (RND) +/- intraoperative radiotherapy (IORT), or EBRT +/- hyperthermia, or chemotherapy +/- hyperthermia. Chemotherapy was used in 22 (30%) patients. Median follow-up was 20 months (range: 2 to 308 months).

RESULTS

The 3-, 5-, and 10-year actuarial overall survival following retreatment were 49, 37, 18%, respectively. Thirty-six patients (49%) were free of further local-regional recurrence after retreatment. The 3-, 5-, and 10-year local-regional progression-free rates were 52, 40, and 38%, respectively. On univariate analysis, histologic type (p < 0.0001), interval to recurrence (p = 0.034), and treatment modality for early-stage disease (p = 0.01) were significant prognostic factors for overall survival, with age being marginally significant (p = 0.053). For local-regional progression-free rate, only histology was significant (p = 0.035). On multivariate analysis, age (p = 0.026), histology (p = 0.015), and interval to recurrence (p = 0.030) were significant for overall survival, and only histology (p = 0.002) and presence of complications (p = 0.016) were significant for local-regional progression-free rate. Of the 64 reirradiated patients, late complications were documented in 29 (45%) patients. The late complications were permanent in 21 (33%) and severe in 15 (23%) patients.

CONCLUSION

Retreatment using radiotherapy alone or in combination with other treatment modalities can achieve long-term local-regional control and survival in a substantial proportion of patients with locally recurrent nasopharyngeal carcinoma. Age, histology, and interval to recurrence were independent prognostic factors for overall survival, but only histology and presence of complications were significant for local-regional progression-free rate.