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

External Radiotherapy in the Treatment of Tonsillar Carcinomas. Analysis of 183 Cases

A retrospective analysis of 183 consecutive patients with tonsillar carcinoma obserevd from 1970 through 1984 and treated by external radiotherapy was carried out. The data were analyzed retrospectively to determine the factors affecting prognosis. Tumor size (T) and lymph node involvement (N) were found to be predominant prognostic factors. The difference in 5 year survival rate between T2 and T3 tumors was significant, and that between N1 and N3 was highly significant, whereas difference in survival could be found between N0 and N1 groups. The primary tumor was controlled by radiotherapy alone in 90% of cases of T1 lesions, 58% of T2, 37% of T3 and 11% of T4, and lymph node metastases was controlled in 70% of N1 cases, 0 of N2 and 15.5% of N3. Twenty-three patients underwent salvage surgery after radiotherapy had failed and the actuarial 5 year survival rate was 75% for stage I, 40% for stage II, 30% for stage III and 13% for stage IV.

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.

Proton radiation for treatment of cancer of the oropharynx: Early experience at Loma Linda University Medical Center using a concomitant boost technique

PURPOSE

To assess accelerated fractionation using photon and proton radiation to improve local control and reduce complications in treating locally advanced oropharyngeal cancer.

METHODS AND MATERIALS

Twenty-nine patients with localized Stage II-IV oropharyngeal cancer received accelerated photon and proton radiation, 75.9 GyE in 45 fractions/5.5 weeks, to the primary disease, involved lymph nodes, and potential areas of subclinical spread. Follow-up ranged from 2 to 96 months.

RESULTS

Five-year actuarial control for local disease was 88%, and for neck node disease, 96%; yielding a 84% locoregional control rate at 5 years. Four patients developed distant metastases. The 5-year actuarial locoregional control rate was 84%. The actuarial 2-year disease-free survival rate was 81%; at 5 years, it was 65%. All patients completed the prescribed treatment; though aggressive nutritional and anesthetic support was necessary. Late Grade 3 toxicity was seen in 3 patients.

CONCLUSIONS

Protons used as a concomitant boost with photons effectively delivered an accelerated time-dose schedule to the cancer with a more tolerable schedule to surrounding normal tissues. Preliminary results reveal increased locoregional control without increased toxicity. Future studies must evaluate the optimum time-dose schedule.

The role of brachytherapy in head and neck cancer

By precision dose delivery to a well-defined target, brachytherapy fulfills the complementary goals of delivering sufficient dose for tumor cell kill while sparing normal adjacent structures. The unique properties of this modality, either used alone or implemented in a combined modality setting with surgery or external-beam irradiation, offer an ideal means of enhancing the therapeutic ratio by exploiting the effect of local therapies while respecting normal tissue tolerance. Brachytherapy also provides an effective technique for the retreatment of patients with recurrent, persistent, or second primary head and neck malignant tumors in a previously irradiated region. The benefits of this treatment modality are reflected in excellent reported local control rates, shortened overall treatment times, reduced functional deficits, improved quality of life, and decreased costs. Successful brachytherapy relies, however, on close collaborative efforts between radiation oncologists and surgeons, careful assessment of the patient, precise planning, and technique that adheres to the rules of a system. Brachytherapy has been clearly identified as an effective, safe, and appealing modality in the treatment of head and neck malignancies.

Modern brachytherapy: current state and future prospects

This article reviews the current trends and future developments in brachytherapy. Established techniques including interstitial and high-dose rate brachytherapy are discussed with particular reference to lung, oesophageal, cervical and endometrial cancer. Intra-operative high-dose rate brachytherapy and other new techniques are also mentioned.

Pulsed dose rate and fractionated high dose rate brachytherapy: choice of brachytherapy schedules to replace low dose rate treatments

PURPOSE

Pulsed dose rate (PDR) brachytherapy is a new type of afterloading brachytherapy (BT) in which a continuous low dose rate (LDR) treatment is simulated by a series of "pulses," i.e., fractions of short duration (less than 0.5 h) with intervals between fractions of 1 to a few hours. At the Dr. Daniel den Hoed Cancer Center, the term "PDR brachytherapy" is used for treatment schedules with a large number of fractions (at least four per day), while the term "fractionated high dose rate (HDR) brachytherapy" is used for treatment schedules with just one or two brachytherapy fractions per day. Both treatments can be applied as alternatives for LDR BT. This article deals with the choice between PDR and fractionated HDR schedules and proposes possible fractionation schedules.

METHODS AND MATERIALS

To calculate HDR and PDR fractionation schedules with the intention of being equivalent to LDR BT, the linear-quadratic (LQ) model has been used in an incomplete repair formulation as given by Brenner and Hall, and by Thames. In contrast to earlier applications of this model, both the total physical dose and the overall time were not kept identical for LDR and HDR/PDR schedules. A range of possible PDR treatment schedules is presented, both for booster applications (in combination with external radiotherapy (ERT) and for BT applications as a single treatment. Because the knowledge of both alpha/beta values and the half time for repair of sublethal damage (T 1/2), which are required for these calculations, is quite limited, calculations regarding the equivalence of LDR and PDR treatments have been performed for a wide range of values of alpha/beta and T 1/2. The results are presented graphically as PDR/LDR dose ratios and as ratios of the PDR/LDR tumor control probabilities.

RESULTS

If the condition that total physical dose and overall time of a PDR treatment must be exactly identical to the values for the corresponding LDR treatment regimen is not applied, there appears to be less need for strong fractionation in PDR schedules. If the overall time is at least as long as that of the LDR schedule and if the total physical dose is (slightly) adapted, PDR schedules can be designed using longer pulse intervals of up to 3 h. Schedules with sufficiently long intervals have significant logistic advantages in terms of patient care and treatment tolerance. However, in general, PDR schedules that apply more fractionation have a lower risk of overdosing normal tissues in comparison to fractionated HDR schedules. Applying probable ranges for the values of alpha/beta and T 1/2, the model calculations indicate that the differences in effects between the proposed fractionated HDR and PDR schedules could be rather small. To detect the magnitude of these differences, (randomized) clinical studies with rather large patient groups might be needed.

CONCLUSIONS

Pulsed dose rate treatment schedules with longer intervals of up to 3 h appear adequate to replace LDR treatment schedules. Whether PDR schedules can, indeed, replace LDR treatment schedules and whether they offer detectable advantages over schedules with less fractionation (fractionated HDR) should be tested in clinical studies.

Oropharyngeal carcinoma treated with radiotherapy: a 30-year experience

PURPOSE

This study was done to determine the outcome in patients with oropharyngeal carcinoma treated at the University of Florida with radiotherapy alone to the primary site, for comparison with reported results of other types of treatment.

METHODS AND MATERIALS

Of a consecutive cohort of 785 patients with biopsy-proven, previously untreated, invasive squamous cell carcinoma of the oropharynx, this report is based on the 490 patients who had continuous-course irradiation with curative intent at the University of Florida between October 1964 and January 1991. All patients had a minimum 2-year follow-up. Forty-eight percent had Stage T3 or T4 disease, and 64% had clinically apparent neck node metastases. The median radiation dose was 68 Gy for once-a-day treatment and 76.8 Gy for twice-a-day treatment. Patients with advanced neck node disease had planned neck dissection(s) after radiotherapy.

RESULTS

The overall local control rate after radiotherapy alone was 73%. The ultimate local control rate (including surgical salvage) was 78%. At 5 years, the probability of control of neck disease was 85%; control above the clavicles, 67%; absolute survival, 44%; cause-specific survival, 77%; distant metastasis (as the first or only site of failure), 11%. Thirteen patients (2.6%) experienced severe treatment complications.

CONCLUSION

Radiotherapy results in tumor control and survival rates comparable with rates achieved with combined irradiation and surgery, with less morbidity.

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.

Radiation therapy for squamous cell carcinoma of the tonsil

OBJECTIVE

To characterize the patient population referred for radiation therapy for tonsillar cancer and to assess the effectiveness of use of only radiation therapy in this population.

DESIGN

We retrospectively reviewed the medical records of 21 patients referred to the Mayo Clinic in Rochester, Minnesota, from 1970 through 1988 for radiation therapy for squamous cell carcinoma of the tonsillar region.

MATERIAL AND METHODS

The median age of the 21 study patients was 65 years (range, 45 to 92), and the male:female ratio was 12:9. In all patients, follow-up continued until death or for 2.25 to 16.25 years. Of the 21 patients, 17 had tumors that were either surgically unresectable or medically inoperable, and 20 had clinical stage III or IV disease. The median total dose of irradiation was 55 Gy.

RESULTS

Local control of the tonsillar cancer was as follows: T2, four of five patients; T3, seven of seven; and T4, five of nine. Thus, the local control rate was 76%. No associations were discovered among local control, total dose of radiation therapy, dose per fraction, overall duration of treatment, age, sex, or reason for referral for radiation therapy. Control of metastatic cervical adenopathy was as follows: clinical stage N1, seven of seven patients; N2, six of seven; and N3, one of one. (Six study patients had no nodal involvement.) The estimated 5-year cause-specific survival and overall survival rates were 77% and 31%, respectively.

CONCLUSION

This study substantiates the effectiveness of radiation therapy in patients with squamous cell carcinoma of the tonsil.

Tonsil cancer. Patterns of failure after surgery alone and surgery combined with postoperative radiation therapy

BACKGROUND

The authors determined the patterns of treatment failure in patients treated with surgery alone or surgery combined with postoperative radiation therapy for squamous cell carcinoma of the tonsil.

METHODS

Seventy-two patients underwent surgery alone (56) or surgery and postoperative adjuvant radiation therapy (16). All patients were followed up until death (40 patients) or for a minimum of 3.5 years. For patients treated with surgery alone, clinic notes, operative notes, and pathology reports and slides were reviewed to identify clinical or pathologic predictors of recurrence above the clavicles, cause-specific survival, and overall survival. For patients undergoing postoperative adjuvant radiation therapy, demographic, treatment, and pathologic variables were analyzed to identify factors associated with control of disease above the clavicles, disease-free survival, and overall survival.

RESULTS

The main pattern of treatment failure was above the clavicles. It occurred in 39% of patients treated with surgery alone and was significantly related (P = 0.002) to the overall clinical TNM stage. Disease recurrence above the clavicles occurred in 31% of patients undergoing surgery and postoperative adjuvant radiation therapy, despite their more advanced neck disease. Five-year overall survival for patients with clinical Stage III and IV disease who were treated with surgery and post-operative adjuvant radiation therapy was 100% and 78%, respectively. Five-year overall survival for patients treated with surgery alone who had clinical Stage III, IVA, or IVB disease was 56%, 43%, and 50%, respectively.

CONCLUSION

We recommend postoperative adjuvant radiation therapy for patients with clinical Stage III or IV squamous cell carcinoma of the tonsil who have undergone complete surgical resection because this appears to improve control of disease above the clavicles and overall survival.

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.

Place of Iridium 192 implantation in definitive irradiation of faucial arch squamous cell carcinomas

PURPOSE

We have reviewed the results of 165 T1 and T2 squamous cell carcinomas of the faucial arch treated by definitive irradiation including or not Iridium 192 brachytherapy to ascertain whether a significant relationship existed between Iridium implantation, local control, complications, and survival.

METHODS AND MATERIALS

From March 1971 to November 1990, 58 T1 and 107 T2 (NO: 107/165; N1: 30/165; N2: 9/165; N3: 19/165) biopsy proven squamous cell carcinomas of the tonsillar region (104/165) and the soft palate and uvula (61/165) were treated in Henri Mondor Hospital by definitive irradiation with curative intent. From 1971 to 1981 (period 1), only guide gutter technique was available, so that implants were reserved for small tumors: patients were either managed by definitive telecobaltherapy to tumor site and neck node areas (Group 1; n = 48; mean dose: 70 Gy; confidence interval: +/- 5.5; 5 fractions of 1.8 Gy per week) or by exclusive Iridium implant (Group 2; n = 11; all T1NO; 64 Gy +/- 4.8) or by a combination of external beam radiation therapy to tumor site and neck nodes areas and Iridium implant (Group 3; n = 40). In 1981 (Period 2), a new plastic tube technique, which enables implantation of larger areas, was introduced in the department and all patients (Group 4; n = 66) were then managed by external radiation therapy (Group 3 + 4: 47 Gy +/- 4.3) followed by an Iridium implant (31 Gy +/- 10.5). Clinically positive neck nodes either received additional external dose with electrons or were excised.

RESULTS

Overall 5-year survival (Kaplan Meier) was 21%, 50.5%, and 60% in groups 1, 2, and 3 + 4, respectively (p < 0.001, log rank). Five-year local control was 58%, 100%, and 91%, respectively (p < 0.001). Five-year necrosis rate was 4.5%, 20.5% and 18%, respectively (N.S.). Comparison of results between the two periods of the study (Group 1 + 2 + 3 vs. group 4) show that these two groups are statistically comparable according to site and size of tumor and N status and that both local control (77% vs. 94% at 5 years; p < 0.01) and disease-free survival (56% vs. 71%; p = 0.03) were improved after 1980, while there was a trend to an increase in overall survival (42% vs. 53% at 5 years; p = 0.08); nodal control (86% vs. 95% at 5 years), and necrosis rate (11% vs. 20% at 5 years) were not modified. Multivariate analysis showed that both local control (p < 0.0001) and overall survival (p < 0.0001) were improved when tumor was implanted.

CONCLUSION

We recommend then to treat T1 and T2 squamous cell carcinomas of the faucial arch by external radiation therapy to tumor site and neck areas (45 Gy/25 fractions/5 weeks) followed by a 30 Gy Iridium implant and, for patients with clinically positive nodes, either a further 25-30 Gy electron beam irradiation to the nodes or neck node dissection.

Long-term treatment results of postoperative radiation therapy for advanced stage oropharyngeal carcinoma

BACKGROUND

The authors report the long-term treatment results for advanced stage base of tongue (BOT) and tonsillar fossa (TF) carcinomas treated with surgery and postoperative radiation therapy (RT) at Memorial Sloan-Kettering Cancer Center.

METHODS

Between 1973 and 1986, 51 patients with squamous cell carcinoma of the BOT (n = 31 patients) and TF (n = 20 patients) were treated with surgery plus RT. Indication(s) for RT included: advanced disease (Stage T3/T4, 34 patients [66%]); close or positive margins (33 patients, 64%) and multiple positive neck nodes (43 patients, 84%).

RESULTS

The 7-year actuarial local control rates for BOT and TF lesions were 81% and 83%, respectively. Local control was achieved in 17 of 18 (94%) patients with T3 lesions, and 12 of 16 (75%) patients with T4 lesions. Among patients with positive or close margins who received postoperative doses of 60 Gy or more, the long-term control rate was 93%. The presence of a treatment interruption had a negative effect on the local control rates. The actuarial control among patients who required a treatment break was 64%; for those not requiring interruption of their treatment, the actuarial control was 93% (P = 0.05). At 7 years, the overall survival for all patients was 52%, and the disease-free survival was 64%. The actuarial incidence of neck failure was 21% and 18% for BOT and TF, respectively. The likelihood of having distant metastasis at 7 years for all patients was 30%. The actuarial incidence of having a second malignancy was 35% for patients with BOT disease. Second malignancy was not observed among patients with TF lesions.

CONCLUSIONS

The authors conclude that surgery and postoperative RT can provide excellent long-term, disease-control rates for patients with advanced BOT and TF tumors. However, current strategies for BOT lesions have been directed at tongue preservation without surgery.

Second head and neck cancers following radiation therapy of T1 and T2 cancers of the oral cavity and oropharynx

The risk of second cancer in the head and neck region following definitive radiation therapy was evaluated among 600 patients who were treated for T1 and T2 cancers of the oral cavity and oropharynx at the Henri Mondor hospital between January 1970 and March 1987. Seventy-five patients (12.5%) were managed with external irradiation only, 243 (40.5%) with RT and Iridium 192, and 282 (47%) with Iridium 192 alone. One hundred fifteen patients (19%) developed a second cancer from 3 to 183 months after initial therapy (median: 32 months), including 69 patients (11.5%) in whom the second malignancy was diagnosed in the head and neck region. An increased and constant actuarial risk of development of second head and neck cancer was found (2.7%/year of observation). Univariate analysis showed that age, sex, stage, and modality of the initial treatment did not influence the risk of second head and neck cancer; there was a greater risk of second head and neck malignancy for those patients with soft palate carcinoma (p less than 0.05). Multivariate analysis revealed that the only group of patients who developed a second head and neck cancer more frequently were those who were irradiated with Iridium 192 only (p = 0.0076). There was a trend toward a greater risk of second head and neck malignancy for those with soft palate carcinoma (p = 0.059). Radical treatment of the second head and neck malignancy by surgery and/or re-irradiation was performed for 67% of patients. Patients initially treated by Iridium 192 only could undergo salvage treatment more often than those who previously received external beam radiotherapy (79% vs 53%, p = 0.02). The overall 2-year and 5-year survivals after the diagnosis of the second head and neck cancer were 32% and 10%, respectively.

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.

Carcinoma of the tonsillar region: potential for use of proton beam therapy

An investigation of treatment results in tonsillar region carcinomas was conducted, with particular attention to local control and morbidity from current therapy. The purpose of the investigation was to identify problems that might be resolvable with a superior treatment modality. A search was made of the National Library of Medicine's MEDLINE database, covering local control, survival, and morbidity from current therapies; dose-response relationships; and prognostic indicators. Three-dimensional radiotherapy plans were developed for representative cases, comparing photon-beam plans with proton-beam plans. Locoregional control is a major problem, and morbidity from standard therapy is high. Comparative treatment plans reveal that proton beams can deliver higher doses to the tumor volume, with significantly reduced radiation to salivary glands and mandible, than can photon-beam irradiation. The absorption and distribution characteristics of protons provide the radiation oncologist with a superior tool for treating patients with tonsillar region carcinomas. The therapeutic advantage accrues from these superior characteristics, not from an inherent biologic advantage.

Carcinoma of the tonsillar fossa: a nonrandomized comparison of irradiation alone or combined with surgery: long-term results

The results of therapy are reported in 296 patients with histologically proven epidermoid carcinoma of the tonsillar fossa; 127 were treated with irradiation alone (5,500 to 7,000 cGy), 133 with preoperative radiotherapy (2,000 to 3,000 cGy) or were initially planned for preoperative irradiation but treated with radiotherapy alone, and 36 with postoperative irradiation (5,000 to 6,000 cGy). The operation in all but 4 patients consisted of an en bloc radical tonsillectomy with ipsilateral lymph node dissection. Actuarial 5-year no evidence of disease (NED) was as follows: survival rates for patients with T1 tumors, 76%; T2, 54%; T3, 45%; and T4, 20%. Patients with no cervical lymphadenopathy or with a small metastatic lymph node (N1) had better relapse-free survival (60% to 70% at 5 years) than those with large or fixed lymph nodes (30% to 40%). Primary tumor recurrence rate in the T1-T2 groups was about 20% in patients treated with irradiation and surgery and 30% for those treated with irradiation alone (difference not statistically significant), 30% in patients with stage T3 lesions in all treatment groups, and 33% in patients with T4 disease treated with surgery and postoperative irradiation compared to 52% with irradiation alone (p = 0.03). The overall recurrence rate in the neck was about 20% for the N0 patients, 25% for N1, and 30% for those with N2 and N3 cervical lymph nodes in the 4 treatment groups. The incidence of contralateral neck recurrences was about 8% with the various treatment modalities.(ABSTRACT TRUNCATED AT 250 WORDS)

Iridium 192 implantation of squamous cell carcinomas of the oropharynx

From 1970 to 1984, 127 patients with T1 or T2 carcinomas of the oropharynx were treated with external irradiation to the primary tumor and neck nodes to a dose of 45 Gy, followed by a further 30 Gy delivered by an iridium 192 implant to the primary tumor. Patients with clinically positive nodes had either further neck irradiation using electrons or a neck dissection. Crude 5-year disease-free survival was 66% for tonsillar carcinomas, 43% for soft palate, and 51% for base of tongue. Local control was 98%, 85%, and 76%, respectively. Regional control was 97% for N0 patients and 88% for N1-3. Soft tissue ulceration occurred in 17 patients; all healed spontaneously. The high rate of local control achieved in these patients while preserving function and minimizing xerostomia supports the use of this approach.

Exclusive radiation therapy: the treatment of early tonsillar tumors

One hundred and ninety-three T1 or T2 tumors of the tonsillar region have been treated by exclusive external irradiation between 1970 and 1982. Seventy-five percent of these tumors were classified as T2. There was no relationship between T and N stages. The nodal involvement was essentially linked to the macroscopic appearance of the tumor (superficial or nodular) and to the histology. The 5-year survival rate of the whole population was 58%. N stage and macroscopic appearance only influenced the survival. The local control was 88% for T1, 79% for T2. The main prognostic factors for local control were the histological type, with a 93% local control rate for poorly differentiated tumors versus 73% for well differentiated ones, and the macroscopic appearance, with a 83% local control rate for nodular tumors versus 75% for superficial ones. Superficial tumors spreading forward the anterior pilar have a higher local failure rate. All the patients' charts have been reviewed, and we observed a high percentage of marginal recurrences. The technique of irradiation, above all in case of a superficial tumor, must take into account the possibility of "geographic miss" and keep large safety margins.

Effect of dose rate on local control and complications in the reirradiation of head and neck tumors with interstitial iridium-192

Interstitial Iridium-192 was used as the sole treatment for 23 previously irradiated patients with recurrent or second primary malignancy in the head and neck region. Doses used in initial external beam treatment ranged from 50.0 to 72.0 Gy, in daily fractions of 180 to 200 cGy. Retreatment with interstitial implant using the Quimby system delivered total doses between 38.5 and 60 Gy, with hourly dose rates of 30 to 66 cGy. Local control in the implanted volume was seen in 21 of 23 patients at 5 to 34 months post-implant (median 10 months). Dose rate (hourly dose delivered at 0.5 cm beyond the periphery of the implanted tumor volume) did not affect local control, but did have a significant impact on severe complications (soft tissue necrosis and fistulae; p = 0.26). No effect on either local control or complication rate was found for volume of implant, initial external beam radiation dose, time to recurrence, or anatomic site of treatment. These findings suggest that interstitial irradiation is effective treatment for head and neck cancers in previously irradiated sites. Dose rates as low as 32 cGy/hr provided adequate local control, with few long-term complications to date; doses above 42 cGy/hr may be associated with severe and even fatal complications.

Combined external irradiation and interstitial implantation for T1 and T2 epidermoid carcinomas of base of tongue: the Creteil experience (1971-1981)

Forty-eight patients with T1 or T2 epidermoid carcinomas of the base of tongue were treated at the Henri Mondor Hospital between 1971 and 1981. Forty-one patients received moderate dose 60Co external beam irradiation (mean: 48.6 Gy) to the primary tumor and regional nodes, followed by an interstitial iridium 192 implant to the primary tumor (mean: 32 Gy). This completed the treatment for the 30 node negative patients, but those with clinically positive nodes were managed by either an additional electron beam boost to the involved nodes or a neck dissection. Seven tumors were treated exclusively by implantation to the base of tongue (mean: 63 Gy). Five-year crude disease-free survival is 50% with 35% of patients dying of recurrent disease. Definitive local control for T1 lesions is 85% (11/13) and for T2 is 71% (25/35). A dose response effect was observed with local control of 79% (26/33) obtained with a combined dose greater than or equal to 75 Gy, but only 50% (4/8) for less than or equal to 70 Gy. For N0 patients definitive regional control is 97% and for N1-3 is 89%. Minor or moderate soft tissue ulceration was observed in 12 patients, including 3 cases that progressed to osteonecrosis. None required surgical intervention. No correlation exists between necrosis and tumor size or total dose.

Definitive radiation treatment for early stage carcinoma of the soft palate and uvula: the indications for iridium 192 implantation

From 1971 to 1984 59 T1 and T2 carcinomas of the soft palate and uvula were treated definitively by irradiation at the Henri Mondor hospital. Included are ten patients previously irradiated to the oropharyngeal area for either a carcinoma of the soft palate or another malignancy. Sixteen patients were treated by external irradiation alone, 14 by Iridium 192 implantation, and 29 by a combination of the two. Two techniques of implantation were used: the guide gutter technique (33 patients) and the plastic tube technique (10 patients). Clinically negative neck nodes (51/59) either received prophylactic telecobalt therapy (39/51) or were surveilled (12/51). Clinically involved nodes (8/59) were managed either by external irradiation alone (4/8) or combined with neck dissection (4/8). Local failure was 25% (4/16) after exclusive telecobalt therapy, 18% (5/19) after combined telecobalt therapy and implantation, and 0% (0/14) after Iridium 192 implantation alone. No local failures were seen with the plastic tube technique (0/10) as compared to 15% (5/33) for guide gutters. Only two nodal failures were observed (2/59: 3%). Crude 5-year disease-free survival was 33%. Severe complications were limited to one osteonecrosis, one soft tissue necrosis, and one partial palatal incompetence. Salivary impairment was reduced when implantation was used for part or all of the treatment. We recommend 45 Gy external radiation followed by 30 Gy from Iridium 192 implantation using the plastic tube method unless there has been prior oropharyngeal irradiation, in which case we give 60 Gy from implantation alone. For clinically negative neck nodes, we recommend 45 Gy prophylactic external neck irradiation. For clinically positive lymph nodes, this should be followed by either a 25 to 30 Gy boost to the involved nodes or a neck dissection.

Squamous cell carcinoma of the tonsillar area treated with radical irradiation

This is an analysis of 136 patients treated with radiation therapy alone (104) or in conjunction with planned neck dissection (32) for squamous cell carcinoma of the tonsillar area between October 1964 and August 1983. All patients have a 2-year follow-up and 94 (69%) have a minimum 5-year follow-up. Patients were excluded from analysis of disease control at the primary site and/or neck if they died within 2 years of treatment with that site continuously disease-free. All patients were treated with continuous-course irradiation; those treated with the planned split-course technique are not included. Once-a-day fractionation was used in 105 patients and twice-a-day fractionation in 31 patients. External beam alone was used in 93 patients, and external beam followed by a radium needle implant boost to the primary site was employed in 43 patients. Rates of initial local control with irradiation and ultimate local control after surgical salvage of irradiation failures are as follows: T1, 10/12 (83%) and 12/12; T2, 36/46 (78%) and 41/46 (89%); T3, 28/39 (72%) and 28/39 (72%); T4, 5/16 (31%) and 5/16 (31%). Local control data are also presented as a function of tumor site within the tonsillar area, total dose, dose per fraction, and external beam alone versus external beam plus radium needle implant. The 5-year determinate survival rates by modified AJCC stage are as follows: I, 3/3; II, 13/14; III, 14/17; IVA, 6/14; and IVB, 4/19.