A method of interstitial tonsillo-palatine implants

Radiotherapy as Initial Treatment for Carcinomas of Tonsillar Region

For this study we have reviewed 186 carcinomas of the tonsillar region, i.e., the lateral wall of the oropharynx, treated from January 1959 to December 1973 at this Institute. In 148 patients (79.6%) the primary tumor and the lymphatic areas were treated with 60Co-teletherapy (TCT). In 15 cases (8.1%) the primary lesion was removed by transoral surgery, followed by irradiation of the tonsillar region and lymphatic areas with TCT. In 23 patients (12.3%) the primary tumor was treated with interstitial curietherapy, after which a radical homolateral neck dissection was performed on 10 of them; the neck was not treated in the remaining 13 cases, initially N0. As far as the cases initially treated with TCT alone are concerned, disease-free survival at 5 years was 42.5% for T1 cases and under 30% for T2, T3, whereas it was only 6.5% for T4. The most frequent failure cause of TCT was local relapse, isolated or associated with a nodal relapse. Local failures were nearly always central. On the contrary, if the field extension was adequate, there were very few nodal failures, at least in initially N0 or N1 cases. Our study recommends a revision of the current attitude towards the treatment of carcinomas of the tonsillar region.

Influence of tumoral, radiobiological, and general factors on local control and survival of a series of 361 tumors of the velotonsillar area treated by exclusive irradiation (external beam irradiation+brachytherapy or brachytherapy alone)

PURPOSE

To evaluate statistically the factors influencing the therapeutic results.

METHODS AND MATERIALS

A statistical study was carried out concerning 361 patients treated from 1977 to 1991 for velotonsillar carcinoma. They received either brachytherapy alone (18) or a combination of external beam irradiation and brachytherapy (343 patients) using an afterloading iridium technique in plastic tubes. The distribution of patients according to the localization was: 128 tonsils, 134 soft palates, 9 posterior pillars, 63 anterior pillars, and 27 glossotonsillar sulcus. The patients were staged as follows: 90 T1, 141 T2, 119 T3, 2 T4, 9 Tx with 230 N0, 93 N1, 9 N2, 20 N3, and 9 Nx.

RESULTS

The results at 5 and 10 years show: local control 80% and 74%, locoregional control 75% and 70%, overall survival 53% and 27%, specific survival 63% and 52%, respectively. The univariate study shows at 5 years a better local control for T1T2 (87%) compared with T3 (67%) with p = 0.00004. The locoregional control is better for N0 (80%) than for N+ (55%) with p = 0.002. This is the same for the overall survival (59% vs. 42%, p = 0.002). Tumors with an extension to the mobile tongue or the base have a poor prognosis (p < 0.002). The radiobiological factors show less recurrences if the total duration of the treatment is < 55 days, the number of days between External Beam Irradiation and brachytherapy is < 20. The security margin seems important also.

CONCLUSIONS

For the combination external irradiation and brachytherapy, the multivariate study for local control shows that ony T, localization, and the total duration of treatment are significant. For complications, classified into four grades, only the dose rate is significant.

Iridium-192 interstitial implant and external beam radiation therapy in the management of squamous cell carcinomas of the tonsil and soft palate

PURPOSE

To evaluate the results, techniques, indications and complications of interstitial brachytherapy in the management of squamous cell carcinomas of the tonsil and soft palate, we reviewed the Stanford University Medical School experience with this modality.

METHODS AND MATERIALS

Between May 1975 and January 1990, 37 patients with squamous cell carcinomas of the Tonsillo-Palatine region were treated with a combination of external beam irradiation and a removable Iridium-192 interstitial implant. The mean age of these patients was 56. Twenty-two were males and 15 were females. The stage distribution included four patients with Stage I, 5 with Stage II, 10 with Stage III, and 18 with Stage IV cancers. Thirty-two percent (12/37) of these patients had T3 or T4 lesions. Forty-nine percent (18/37) had stage N2 or N3 cervical lymphadenopathy. All 37 patients received initial external beam irradiation to the primary, bilateral necks, and supraclavicular region (mean dose: 5400 cGy, range 4000-6600). Eighteen patients (49%) also received neck dissections. All 37 patients received an interstitial Irridium-192 implant using a combination intraoral swage and external looping technique. The mean dose was 2700 cGy (range 2000-4000 cGy) to an average volume of 24 cc (range 5-81).

RESULTS

Local control was obtained in 95% (35/37) of the patients. Eighty-seven percent (32/37) of the patients have remained disease-free in the neck. Nine patients have developed second primary lesions, and one developed pulmonary metastasis. Fifteen patients have died (6 succumbed to their cancers, 6 to second primaries, 2 to intercurrent disease, 1 from an unknown cause). The actuarial freedom from relapse is 75%, and overall survival is 64% at 5 years, with a mean follow up of 43 months (range 5-110). Complications were limited to one case of osteoradionecrosis of the mandible and one tonsillar ulcer. Functional and esthetic integrity was preserved in most of these patients.

CONCLUSION

Iridium-192 interstitial implant boost combined with external beam radiation therapy is a safe and effective therapy in the management of locally advanced carcinomas of the tonsil and soft palate.

Velotonsillar squamous cell carcinoma: 277 cases treated by combined external irradiation and brachytherapy--results according to extension, localization, and dose rate

From 1977 to 1987, 277 patients with velotonsillar cancer (oropharyngeal cancer excluding base of tongue and valleculae) were treated by brachytherapy either alone (14 patients) or combined with external beam irradiation (263 patients) using a new afterloading Iridium-192 technique. The distribution of patients according to the localisation was as follows: 106 tonsillar region, 98 soft palate, 45 anterior pillar, 8 posterior pillar and 20 pharyngoglossal sulcus. According to the UICC TNM classification of 1979, the patients were staged as follows: 65 T1, 103 T2, 101 T3, 8 TX. 172 patients were NO, 74 N1, 3 N2, 20 N3 et 8 NX. According to the tumor extension, the 5 year actuarial local control, locoregional control, specific survival and overall survival by T stage (T1 [65 pts], T2 [103 pts.], T3 [101 pts]) were respectively: local control: 89%, 86%, 69%; locoregional control: 84%, 80%, 67%; specific survival (excluding patients dead with intercurrent disease or second cancer): 78%, 62%, 46%; overall survival: 62%, 53%, 43%. No local recurrence was detected after 3 years. According to the localization, the tumors arising from the tonsillar region, the soft palate and the posterior pillars (A Group) had a better prognosis than the tumors arising from the anterior pillars and glossotonsillar sulcus (B Group). The complications were classified into four grades according to their extension and duration: Grade 1 (minor) with very small tissue ulcer which healed within 2 months with medical treatment (20%). Grade 2 (moderate) (5%), grade 3 (severe) (1.4%), grade 4 (fatal) (0.4%). The dose rate seemed to be relatively higher in patients with grade 2 and 3 complications (70 cGy per hour on average) versus the dose rate of patients without complications (50 cGy per hour) but the difference was not significant. In conclusion, the brachytherapy boost after external irradiation can be performed under favourable conditions with an acceptable rate of complications. It was set out in order to attempt to improve the local control of the tumor while preserving the salivary function and lessening the muscular fibrosis. It shows how experienced the team is, however only a randomized study would allow to state whether this technique brings about a real improvement especially as for tumors T2 or T3.

Interstitial and external radiotherapy in carcinoma of the soft palate and uvula

Forty-three patients, all male, with limited epidermoid carcinoma of the soft palate and uvula were treated by interstitial implant usually associated with external radiotherapy. Most patients received 50 Gy external irradiation to the oropharynx and neck followed by 20-35 Gy by interstitial iridium-192 wires using either guide gutters or a plastic tube technique. Twelve primary tumors and two recurrences after external irradiation alone had implant only for 65-75 Gy. Total actuarial local control is 92% with no local failures in 34 T1 primary tumors. Only one serious complication was seen. Overall actuarial survival was 60% at 3 years and 37% at 5 years but cause-specific survivals were 81% and 64%. The leading cause of death was other aerodigestive cancer, with an actuarial rate of occurrence of 10% per year after treatment of a soft palate cancer. Interstitital brachytherapy alone or combined with external irradiation is safe, effective management for early carcinoma of the soft palate and uvula but second malignancy is a serious problem.

The place of brachytherapy in the treatment of carcinoma of the tonsil with lingual extension

One hundred forty-four of 170 patients (85%) were seen with cancer of the tonsil and received radical irradiation between 1959 and 1980. A 39% crude 3-year disease-free survival rate and a 51% locoregional control rate were observed. Locoregional relapse related to T Stage was 6, 43, 58, and 64% for T1, T2, T3, and T4, respectively. Fifty-four of 144 patients (37%) showed tongue extension, 20% in T1-T2 stages and 50% in T3-T4 stages. Local relapse was 64% and the 3-year disease-free survival rate was 23% in 39 patients with tongue extension treated with external irradiation alone, versus 33 and 43% respectively for 90 patients with no tongue extension. The increase of lymph node metastases or neck recurrences was not related to tongue extension. In 15 patients with tongue extension, treated with external radiation plus brachytherapy, the local relapse was 40% and the 3-year survival rate 60%. External irradiation plus brachytherapy was significantly related to lower local relapse and increased survival rate compared to external irradiation alone in cancer of the tonsil with tongue extension. The combined modality was not associated with increased risk of radiation complications.

Interstitial radiation therapy for squamous cell carcinoma of the tonsillar region: the Creteil experience (1971-1981)

From July 1971 to December 1981, 33 selected patients with T1, T2 tumors of the tonsillar region were treated according to the following protocol: 1. Telecobalt therapy to the primary site and to neck nodes to a dose of 45 Gy. 2. Brachytherapy to the primary site to a dose of 30 Gy using iridium 192. 3. Boost dose to involved neck nodes with electrons, or radical neck dissection, whether N1, N2, or N3. The actuarial disease-free survival was 76% when all patient groups were included and 80% for the N0 patients. The local control rate was 100%. Disease control in the neck was 94% overall and 100% for the N0 group. These results favor the use of this protocol for superficial, minimally infiltrating tumors less than 4 cm in diameter, without obvious extension to the base of the tongue or retromolar trigone.

192Ir pharyngoepiglottic fold interstitial implants. The key to successful treatment of base tongue carcinoma by radiation therapy

Twenty-eight patients with squamous carcinomas of the base tongue were seen and evaluated in a conjoint Head and Neck Tumor Board at Stanford between 1976 and 1982. Fourteen patients were treated by combined external beam and interstitial irradiation, 11 of whom had Stage III and IV carcinomas (American Joint Committee). An initial dose of 5000 to 5500 rad was first delivered by external beam irradiation in 5 to 5.5 weeks, followed approximately 3 weeks later by an iridium 192 (192Ir) interstitial implant boost by the trocar and loop technique. The key to successful treatment of these neoplasms was found to be the use of a lateral percutaneous cervical technique, which placed horizontal loops through the oropharyngeal wall above and below the hyoid bone; the superior loop included the pharyngoepiglottic fold and the tonsilloglossal groove. Standard multiple loop implants (submentally inserted) of the base tongue from the vallecula anteriorly to the circumvallate papillae were also used routinely. This approach has been successful, since 10 of the 14 patients (71%) remain without evidence of disease (mean follow-up, 32 months). There have been only two local recurrences, both on the pharyngoepiglottic fold in patients who did not receive the now standard pharyngoepiglottic fold/lateral pharyngeal wall implants. No patients have relapsed after 18 months. The other 14 patients were treated prospectively during the same period by combining initial resection, radical neck dissection, and postoperative irradiation. In this group, there were more locoregional failures compared to the group treated with radiation therapy alone (5 tongue recurrences and 7 neck relapses); in addition, more severe complications were noted in these 14 patients who received surgery and postoperative irradiation. The authors believe that combined external beam and interstitial irradiation is effective treatment for base tongue carcinomas, especially when the high-dose distribution includes the adjacent tonsilloglossal groove, pharyngoepiglottic fold, and oropharyngeal wall to and below the level of the hyoid bone, in addition to treating an adequate base tongue volume.

The treatment of cancer of the uvula and soft palate with interstitial radioactive wire implants

A new method of implantation of the soft palate with radioactive wires is described. Experience with 25 patients is reported and the results analyzed. This method of treatment appears to be highly effective and avoids radiation complications.

Carcinoma of the tonsillar region: results of external irradiation

A retrospective analysis is made of 104 patients treated with photon megavoltage radiotherapy for squamous cell carcinoma of the tonsillar region during the period 1965--1975. Moderately differentiated squamous cell carcinoma was the most common histological grade. Fifty-three per cent of the cases presented with cervical lymphadenopathy with three cases of bilateral involvement. The three year local control rate was 100% for Stage I, 74% Stage II, 49% Stage III, and 33% Stage IV. Two Stage III cases and one Stage IV case developed subsequent contralateral neck disease. No patient with either T1N0 or T2N0 tumor failed in the ipsilateral or contralateral neck despite the fact that 42% of the T1N0 cases and 37% of the T2N0 cases were treated with unilateral portals. The prognostic significance of the T and N stages, treatment techniques, as well as dose response relationships are analyzed and the literature is reviewed.