Mise au point sur la curiethérapie des carcinomes épidermoïdes de la cavité buccale et du pharynx

The Role of Brachytherapy in the Management of Oropharyngeal Carcinomas: The Trento Experience

Aims

This study was undertaken to determine the outcome of patients with oropharyngeal cancer treated at the Radiotherapy Department of the Santa Chiara Hospital (Trento, Italy) with brachytherapy alone or combined with external beam radiotherapy (EBRT).

Material and methods

We retrospectively reviewed the medical records of 87 patients with squamous cell carcinoma of the oropharynx treated by radiation therapy between January 1986 and September 1999. The median age was 59 years and all patients had a minimum follow-up of one year. Tumor locations were 46 tonsillar region, 31 soft palate and 10 base of the tongue. The patients were staged as follows: 41 T1, 35 T2, 11 T3 with 70 N0, 9 N1 and 8 N2. They received either brachytherapy alone (14 patients) or a combination of external beam irradiation and brachytherapy (73 patients) using an afterloading iridium technique in a plastic tube.

Results

Overall primary tumor control, including salvage surgery, was 81/87 (93%). Control of metastatic cervical adenopathy was as follows: clinical stage N1, 5/9 patients; N2, 2/8 patients. The estimated five-year cause-specific survival and overall survival rates were 81% and 47%, respectively. After interstitial irradiation severe complications were limited to one case of osteoradionecrosis of the mandible and seven cases of mucosal ulcer.

Conclusion

This study confirms that iridium-192 interstitial implant alone or as a boost after external beam irradiation is a safe and effective therapy in the management of oropharyngeal carcinomas.

Complications following definitive irradiation for cancers of the oral cavity and the oropharynx (in a series of 1134 patients)

PURPOSE

To study the rate and severity of complications in a series of 1134 patients treated by definitive irradiation for tumors of the oral cavity (772 cases) or the oropharynx (361 cases).

METHODS AND MATERIALS

Patients were staged as 29.5% T1, 42% T2, 26% T3, 2.5% T4-Tx, and 74.5% N0 tumors. We treated 364 patients with brachytherapy only (192Ir) for the primary lesion. External irradiation and brachytherapy were combined for 770 patients.

RESULTS

The results included local control and survival. Out of 1134 patients, 330 had 376 complications. Grade 1 complications occurred in 20% of the patients, Grade 2 in 9%; Grade 3 in 4%; and Grade 4 in 0.2%. Of the Grade 1 complications, 78% were soft tissue and only 24% were bone complications. For the more severe grades (2, 3, and 4), there were 56 soft tissue complications and 90 bone complications out of 1340 patients. The statistical analysis included tumor-related factors and treatment-related factors. For the first two factors, only tumor location was significant. The treatment-related factors significant for complications were studied in univariate and multivariate study. This multivariate study confirmed that for soft tissue complications dose rate and volume treated were important (p < 0.001). It also confirmed that for bone complications, total dose > 80 Gy, dose rate > 0.7 Gy/h, and the absence of leaded protection of the mandible were all important factors.

CONCLUSION

This statistical study should allow future reduction of severe complications (Grades 2, 3, 4), if treatment factors inducing them can be taken into account. This is not always possible for very large tumors.