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)

Function Preservation in Head and Neck Cancers

The treatment of head and neck cancers can have a significant impact on function and appearance, which results in impairment of quality of life. Various long-term sequelae of treatment include speech and swallowing difficulty, oral incompetence, trismus, xerostomia, dental caries and osteoradionecrosis. Management has evolved from single modality treatment of either surgery or radiation to multimodality treatment to attain acceptable functional outcomes. Brachytherapy, also known as interventional radiotherapy, with its ability to deliver high doses centrally to the target, has been shown to improve local control rates. Due to the rapid fall-off of the dose of brachytherapy there is better organ at risk sparing as compared with that of external beam radiotherapy. In the head and neck region, brachytherapy has been practiced in various sites, including the oral cavity, oropharynx, nasopharynx, nasal vestibule and paranasal sinuses. Additionally, brachytherapy has also been considered for reirradiation as a salvage. Brachytherapy can also be considered as a perioperative technique together with surgery. Close multidisciplinary cooperation is required for a successful brachytherapy programme. In oral cavity cancers, depending on the location of the tumour, brachytherapy has been shown to preserve oral competence, maintain tongue mobility, maintain speech, swallowing and the hard palate. Brachytherapy in oropharyngeal cancers has been shown to reduce xerostomia and also reduce dysphagia and aspiration post-radiation therapy. For the nasopharynx, paranasal sinus and nasal vestibule, brachytherapy preserves the respiratory function of the mucosa. Despite such an incomparable impact on function and organ preservation, brachytherapy is an underutilised technique for head and neck cancers. There is a strong need to improve brachytherapy utilisation in head and neck cancers.

Brachytherapy of the head and neck: An University of California Los Angeles guide to morbidity reduction

The head and neck (H&N) region is among the most intricate and functional part of our anatomy. Major functional nerves and blood vessels with importance that affect the entire body emanate from the base of skull. Brachytherapy plays an important role as a single modality therapy in early cancer of the lip and oral cavity and a supplemental role in the pharynx or in advanced or recurrent disease. Morbidity in the H&N is intensely personal and disabling. Its avoidance is critical in determining the success or failure of a treatment program, and it is essential to preservation of quality of life. This article summarizes the current literature regarding morbidity related to H&N brachytherapy to aid patients and physicians to achieve optimal outcomes.

[Brachytherapy for head and neck cancers]

The main indications of the brachytherapy of head and neck cancers are the limited tumours of the lip, the nose, the oral cavity and the oropharynx. Nasopharynx tumours are nowadays treated by intensity-modulated radiotherapy. This technique can be exclusive, associated with external radiotherapy or postoperative. It can also be a salvage treatment for the second primaries in previously irradiated areas. If the low dose rate brachytherapy rules remain the reference, the pulse dose rate technique allows the prescription of the dose rate and the optimisation of the dose distribution. Results of high dose rate brachytherapy are now published. This paper reports the recommendations of the Gec-ESTRO, published in 2017, and takes into account the data of the historical low dose rate series, and is upgraded with the pulsed-dose rate and high dose rate series.

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.

Chemoradiotherapy versus surgery followed by postoperative radiotherapy in tonsil cancer: Korean Radiation Oncology Group (KROG) study

Background

Treatment of tonsil cancer, a subset of oropahryngeal cancer, varies between surgery and radiotherapy. Well-designed studies in tonsil cancer have been rare and it is still controversial which treatment is optimal. This study aimed to assess the outcome and failure patterns in tonsil cancer patients treated with either approaches.

Methods

We retrospectively reviewed medical records of 586 patients with tonsil cancer, treated between 1998 and 2010 at 16 hospitals in Korea. Two hundred and one patients received radiotherapy and chemotherapy (CRT), while 385 patients received surgery followed by radiotherapy and/or chemotherapy (SRT). Compared with the SRT group, patients receiving CRT were older, with more advanced T stage and received higher radiotherapy dose given by intensity modulation techniques. Overall survival (OS), disease-free survival (DFS), locoregional recurrence-free survival (LRRFS), distant metastasis-free survival (DMFS), and clinicopathologic factors were analyzed.

Results

At follow-up, the 5-year OS, DFS, LRRFS and DMFS rates in the CRT group were 82, 78, 89, and 94%, respectively, and in the SRT group were 81, 73, 87, and 89%, respectively. Old age, current smoking, poor performance status, advanced T stage, nodal involvement, and induction chemotherapy were associated with poor OS. Induction chemotherapy had a negative prognostic impact on OS in both treatment groups (p = 0.001 and p = 0.033 in the CRT and SRT groups, respectively).

Conclusions

In our multicenter, retrospective study of tonsil cancer patients, the combined use of radiotherapy and chemotherapy resulted in comparable oncologic outcome to surgery followed by postoperative radiotherapy, despite higher-risk patients having been treated with the definitive radiotherapy. Induction chemotherapy approaches combined with either surgery or definitive radiotherapy were associated with unfavorable outcomes.

Electronic supplementary material

The online version of this article (10.1186/s12885-017-3571-3) contains supplementary material, which is available to authorized users.

American Brachytherapy Society Task Group Report: Combined external beam irradiation and interstitial brachytherapy for base of tongue tumors and other head and neck sites in the era of new technologies

Irradiation plays an important role in the treatment of cancers of the head and neck providing a high locoregional tumor control and preservation of organ functions. External beam irradiation (EBI) results in unnecessary radiation exposure of the surrounding normal tissues increasing the incidence of side effects (xerostomy, osteoradionecrosis, and so forth). Brachytherapy (BT) seems to be the best choice for dose escalation over a short treatment period and for minimizing radiation-related normal tissue damage due to the rapid dose falloff around the source. Low-dose-rate BT is being increasingly replaced by pulsed-dose-rate and high-dose-rate BT because the stepping source technology offers the advantage of optimizing dose distribution by varying dwell times. Pulsed-dose and high-dose rates appear to yield local control and complication rates equivalent to those of low-dose rate. BT may be applied alone; but in case of high risk of nodal metastases, it is used together with EBI. This review presents the results and the indications of combined BT and EBI in carcinoma of the base of tongue and other sites of the head and neck region, as well as the role BT plays among other-normal tissue protecting-modern radiotherapy modalities (intensity-modulated radiotherapy, stereotactic radiotherapy) applied in these localizations.

Radiotherapy alone or combined with chemotherapy as definitive treatment for squamous cell carcinoma of the tonsil

This study is aimed at updating our institution's experience with definitive radiotherapy (RT) for squamous cell carcinoma of the tonsil. We reviewed 531 patients treated between 1983 and 2012 with definitive RT for squamous cell carcinoma of the tonsil. Of these, 179 patients were treated with either induction (n = 19) or concomitant (n = 160) chemotherapy. Planned neck dissection was performed on 217 patients: unilaterally in 199 and bilaterally in 18 patients. Median follow-up was 5.2 years for all patients (range 0.1-31.6 years) and 8.2 years for living patients (range 1.9-31.6 years). The 5-year local control rates by T stage were as follows: T1, 94 %; T2, 87 %; T3 79 %; T4, 70 %; and overall, 83 %. Multivariate analysis revealed that local control was significantly influenced by T stage and neck dissection. The 5-year cause-specific survival rates by overall stage were as follows: I, 94 %; II, 88 %; III, 87 %; IVA, 75 %; IVB, 52 %; and overall, 78 %. Multivariate analysis revealed that cause-specific survival was significantly influenced by T stage, N stage, overall stage, fractionation, neck dissection, sex, and ethnicity. Of 77 patients treated with ipsilateral fields only, contralateral neck failure occurred in 1 %. The rate of severe complications was 12 %. Definitive RT for patients with tonsillar squamous cell carcinoma provides control rates equivalent to other modalities with a comparatively low incidence of late complications. Patients with anterior tonsillar pillar or tonsillar fossa primaries that are well lateralized with no base of tongue or soft palate extension may be treated with ipsilateral fields.

Effect of radiotherapy delay in overall treatment time on local control and survival in head and neck cancer: Review of the literature

Treatment delays in completing radiotherapy (RT) for many neoplasms are a major problem affecting treatment outcome, as increasingly shown in the literature. Overall treatment time (OTT) could be a critical predictor of local tumor control and/or survival. In an attempt to establish a protocol for managing delays during RT, especially for heavily overloaded units, we have extensively reviewed the available literature on head and neck cancer. We confirmed a large deleterious effect of prolonged OTT on both local control and survival of these patients.

Compromised quality of life in adult patients who have received a radiation dose towards the basal part of the brain. A case-control study in long-term survivors from cancer in the head and neck region

Background

Adult patients with hypothalamic-pituitary disorders have compromised quality of life (QoL). Whether this is due to their endocrine consequences (hypopituitarism), their underlying hypothalamic-pituitary disorder or both is still under debate. The aim of this trial was to measure quality of life (QoL) in long-term cancer survivors who have received a radiation dose to the basal part of the brain and the pituitary.

Methods

Consecutive patients (n=101) treated for oropharyngeal or epipharyngeal cancer with radiotherapy followed free of cancer for a period of 4 to10 years were identified. Fifteen patients (median age 56 years) with no concomitant illness and no hypopituitarism after careful endocrine evaluation were included in a case-control study with matched healthy controls. Doses to the hypothalamic-pituitary region were calculated. QoL was assessed using the Symptom check list (SCL)-90, Nottingham Health Profile (NHP), and Psychological Well Being (PGWB) questionnaires. Level of physical activity was assessed using the Baecke questionnaire.

Results

The median accumulated dose was 1.9 Gy (1.5–2.2 Gy) to the hypothalamus and 2.4 Gy (1.8–3.3 Gy) to the pituitary gland in patients with oropharyngeal cancer and 6.0–9.3 Gy and 33.5–46.1 Gy, respectively in patients with epipharyngeal cancer (n=2). The patients showed significantly more anxiety and depressiveness, and lower vitality, than their matched controls.

Conclusion

In a group of long time survivors of head and neck cancer who hade received a low radiation dose to the hypothalamic-pituitary region and who had no endocrine consequences of disease or its treatment QoL was compromised as compared with well matched healthy controls.

GEC-ESTRO recommendations for brachytherapy for head and neck squamous cell carcinomas

Both primary and recurrent squamous cell carcinoma of the head and neck are classic indications for brachytherapy. A high rate of local tumor control at the cost of limited morbidity can be achieved with brachytherapy through good patient selection, meticulous source implantation and careful treatment planning. However, no randomized trials have been performed, and there is scant evidence in the literature especially regarding practical clinical recommendations for brachytherapy for head and neck subsites. The Head and Neck Working Group of the European Brachytherapy Group (Groupe Européen de Curiethérapie-European Society for Therapeutic Radiology and Oncology (GEC-ESTRO) therefore decided to formulate the present consensus recommendations for low-dose rate, pulsed-dose rate and high-dose rate brachytherapy. The use of brachytherapy in combination with external beam radiotherapy and/or surgery is also covered as well as the use of brachytherapy in previously irradiated patients. Given the paucity of evidence in the literature, these recommendations are mainly based on clinical experience accumulated by the members of the working group over several decades and the respective publications. The recommendations cover in a general part (1) patient selection, the pre-treatment work up and patient care, (2) treatment strategy, (3) target definition, (4) implant techniques, (5) dose and dose rate prescription, (6) treatment planning and reporting, (7) treatment monitoring (8) catheter removal, and (9) post-treatment patient care and follow-up. The recommendations are then specified for the classical brachytherapy tumor sites following an analogue more focussed structure (patient selection, implant technique, target definition, dose and dose rate prescription, results): lip, oral mucosa, mobile tongue, floor of mouth, oropharynx, nasopharynx, paranasal sinuses.

Useful combination of intra-arterial chemotherapy and radiation therapy for lateral oropharyngeal wall cancer

CONCLUSION

A concomitant treatment of intra-arterial chemotherapy and radiation therapy is a promising therapeutic option for oropharyngeal cancers.

OBJECTIVES

Treatment for oropharyngeal cancer has been far from standardized because of its pathophysiologic complexity and its low incidence. In our department, T1 stage tumors with N0 or N1 status are primarily treated surgically, while T1 tumors with N2 or more advanced lymph node involvement are additionally treated with concomitant chemoradiotherapy (CRT). Treatment for T2, T3, and T4 tumors is based on CRT, but surgery is also performed if necessary.

PATIENTS AND METHODS

The study included 73 patients with squamous cell carcinomas of the lateral oropharyngeal wall who received first-line therapy at our department between May 1993 and October 2003.

RESULTS

The 5-year disease-specific survival by disease stage was 100% for stage I, 90.9% for stage II, 88.2% for stage III, 69.8% for stage Iva, and 22.2% for stage IVb. The overall 5-year disease-specific survival was 71.8%, and the overall 5-year crude survival was 54.1%.

Definitive radiotherapy for tonsillar squamous cell carcinoma

PURPOSE

The purpose of this study is to update our experience with definitive radiotherapy (RT) for carcinoma of the tonsillar area.

PATIENTS AND METHODS

There were 503 patients treated between October 1964 and May 2003 (potential follow-up for at least 2 years). Of these, 198 patients underwent a planned neck dissection and 57 patients received induction (18 patients) or concomitant (39 patients) chemotherapy.

RESULTS

The 5-year local control rates were as follows: T1, 88%; T2, 84%; T3, 78%; and T4, 61%. Multivariate analysis revealed that local control was significantly influenced by T stage, primary site, and fractionation. Local control after RT for early stage cancers was higher for tonsillar fossa/posterior pillar tumors than for those arising from the anterior tonsillar pillar. The 5-year cause-specific survival rates were as follows: I, 100%; II, 86%; III, 84%; IVA, 73%; and IVB, 46%. Multivariate analysis revealed that cause-specific survival was significantly influenced by T stage, overall stage, neck dissection, race, and gender. The incidence of severe late complications was 9%.

CONCLUSION

Based on our data and a review of the literature, definitive RT provides cure rates that are as good as those after surgery, and is associated with a lower rate of severe complications. Patients with lateralized tumors may be safely treated with ipsilateral field arrangements. Our limited experience with intensity modulated radiotherapy suggests that it is as efficacious as conventional RT.

Exclusive brachytherapy for T1 and T2 squamous cell carcinomas of the velotonsillar area: Results in 44 patients

PURPOSE

To evaluate the role of interstitial brachytherapy as an exclusive radiotherapy modality for primary T1-T2 squamous cell carcinomas (SCC) of the velotonsillar area.

METHODS AND MATERIALS

Between 1992 and 2000, 44 patients with T1-T2 SCC of the tonsil (n = 36) and soft palate (n = 8) were treated to the primary with brachytherapy alone (37 patients) or after a limited resection (7 patients). Eight patients had prior external beam radiation therapy (EBRT) for previous head-and-neck carcinoma. Nineteen patients had initial neck dissection. The mean brachytherapy dose was 58.7 Gy, and the mean reference dose rate and Ir-192 linear activity were 58.2 cGy/h and 1.51 mCi/cm respectively.

RESULTS

With a 75-month median follow-up, 1 patient recurred locally. Isolated nodal relapses occurred in 4 patients, none of whom had initial neck dissection, and salvage therapy was successful in 2. Five-year overall and progression-free survival rates were 76% and 68%, respectively. Full-course radiation therapy was possible in 7 of 12 patients who developed a second primary head-and-neck carcinoma. Late toxicity was limited to 6 mild soft-tissue necroses, and was significantly associated with previous surgery to the primary and high linear activity.

CONCLUSIONS

Exclusive brachytherapy for T1-T2 velotonsillar carcinomas is safe and effective, and permits definitive reirradiation for a second head-and-neck cancer. Initial neck dissection should be performed for optimal selection for exclusive brachytherapy.

New Radiation Therapy Techniques for the Treatment of Head and Neck Cancer

This article reviews the most recent technology used in the treatment of head and neck cancer. It discusses brachytherapy, new ways to mix radionuclides for enhanced radiobiologic effects, and different fractionation schemes that have grown in clinical importance. Intensity-modulated radiotherapy has become a mainstay in head and neck cancer treatment, and the authors discuss several popular and emerging approaches. Patient immobilization and imaging are also discussed.

In vivo dosimetry of high-dose-rate brachytherapy: study on 61 head-and-neck cancer patients using radiophotoluminescence glass dosimeter

PURPOSE

The largest in vivo dosimetry study for interstitial brachytherapy yet examined was performed using new radiophotoluminescence glass dosimeters (RPLGDs). Based on the results, a dose prescription technique achieving high reproducibility and eliminating large hyperdose sleeves was studied.

METHODS AND MATERIALS

For 61 head-and-neck cancer patients who underwent high-dose-rate interstitial brachytherapy, new RPLGDs were used for an in vivo study. The Paris System was used for implant. An arbitrary isodose surface was selected for dose prescription. Locations of 83 dosimeters were categorized as on target (n = 52) or on nontarget organ (n = 31) and were also scaled according to % basal dose isodose surface (% BDIS). Compatibility (measured dose/calculated dose) was analyzed according to location. The hyperdose sleeve was assessed in terms of prescription surface expressed in % BDIS.

RESULTS

The spread of compatibilities was larger for on nontarget organ (1.06 +/- 0.32) than for on target (0.87 +/- 0.17, p = 0.01). Within on target RPLGDs, compatibility on <95% BDIS (0.95 +/- 0.10) was better than on > or =95% BDIS (0.84 +/- 0.18, p = 0.02). The number of patients with diameter of hyperdose sleeve > or =10 mm was increased with a dose prescription to <77% BDIS (p = 0.046). For nontarget organs, the maximal positive deviation was 84% of the calculated dose.

CONCLUSIONS

Dose prescription is recommended to >77% and <95% BDIS for reproducibility and elimination of excessive hyperdose sleeve. For organs at risk, radioprotection should be considered even when calculated dose seems sufficiently low. Further development of planning software is necessary to prevent overestimation.

High-dose-rate interstitial brachytherapy for oropharyngeal carcinoma: results of 83 lesions in 82 patients

PURPOSE

Low-dose-rate interstitial brachytherapy (LDRIB) represents an effective modality for treatment of oropharyngeal carcinoma. The drawback is radioexposure of medical personnel. To eliminate this concern, we initiated high-dose-rate interstitial brachytherapy (HDRIB) in 1993. The present study evaluated the efficacy and complications associated with this approach.

METHODS AND MATERIALS

Between 1993 and 2003, HDRIB +/- external radiotherapy was used to treat 83 oropharyngeal squamous cell carcinomas. Median duration of follow-up was 26 months (range, 1-108 months). Of the 82 patients, 76 were previously untreated and 6 displayed previous history of head and neck cancer. T distribution comprised T1 (n = 7), T2 (n = 47), T3 (n = 24), and T4a (n = 5). External radiotherapy of 46 Gy was combined with 21 Gy/3.5 fractions/2 days HDRIB for 68 lesions, and 48 Gy/8 fractions/5 days HDRIB alone was used for 15 lesions. Involved nodes were either boosted by external radiotherapy or resected.

RESULTS

Five-year local control, regional control, cause-specific and overall survival rates were 82%, 84%, 88%, and 64%, respectively. Local control rates for early (T1/T2) and advanced (T3/T4) tumors were 89% and 66%, respectively (p = 0.02). Transient soft tissue necrosis was experienced in 29% of patients. No bone sequelae were observed in previously untreated patients.

CONCLUSIONS

High-dose-rate interstitial brachytherapy could achieve excellent local control and acceptable rates of complication, equivalent to reported results for LDRIB series. Given the advantage of radioprotection, HDRIB may replace LDRIB in the treatment of oropharyngeal carcinoma.

Brachytherapy versus surgery in carcinoma of tonsillar fossa and/or soft palate: late adverse sequelae and performance status: can we be more selective and obtain better tissue sparing?

PURPOSE

To report on the tumor control, adverse late normal tissue sequelae, and functional performance in patients with tonsillar fossa and/or soft palate (SP) tumors. The aim of the study is to validate the use of a more selective clinical target volume in conjunction with highly conformal radiotherapy (RT) techniques to better spare the surrounding normal tissues.

METHODS AND MATERIALS

Between 1986 and 2001, T1-T3 tonsillar fossa/SP tumors were treated in the Erasmus Medical Center using external beam radiotherapy (EBRT) to 46 Gy in 2-Gy fractions to the primary tumor and neck, followed by brachytherapy (BT) to the primary. Neck dissection was performed for node-positive disease (BT group; 104 patients). If BT was not feasible, patients underwent surgery and postoperative RT (PORT) to a dose of 50-70 Gy in 2-Gy fractions (surgery group; 86 patients). Local control, regional control, disease-free survival, and overall survival were determined. Late side effects were scored using the Radiation Therapy Oncology Group criteria. Univariate and multivariate Cox regression analyses were performed for regional failure (RF), with the parameters gender, age, site, TN stage, modality, dose, and overall treatment time. Recurrences in the contralateral neck were also related to significant ipsilateral involvement of the base of tongue and/or involvement of the SP crossing the midline. To determine the performance status scale scores and degree of xerostomia, a survey was conducted among patients living with no evidence of disease and a minimum of 2 years of follow-up. For that purpose, a research nurse interviewed patients regarding eating in public, normalcy of diet, normalcy of speech, and xerostomia.

RESULTS

The tumor control rates after BT vs. surgery at 5 years were 88% vs. 88% for local control; 93% vs. 85% for regional control; 57% vs. 52% for disease-free survival; 67% vs. 57% for overall survival; and 5% vs. 6% for RF. No patient had RF in the contralateral untreated N0 neck (0 of 14 vs. 0 of 15). Multivariate Cox regression analysis for RF was statistically significant for Stage T2 vs. T3 (hazard ratio 0.09) and for the dose to the neck >46 Gy (hazard ratio, 8.7; 95% confidence interval, 1.3-57.1). The significant late side effects in the BT group vs. surgery group were ulcer in 39% vs. 7% (p = 0.001) and trismus in 1% vs. 21% (p = 0.005). The performance status scale scores and response to questions regarding xerostomia for BT vs. surgery revealed no statistically significant differences for eating in public, normalcy of diet, normalcy of speech, and xerostomia. The mean visual analog score for xerostomia was 5.5 in the BT group vs. 6 in the surgery group.

CONCLUSION

Excellent locoregional control was obtained in T1-T3 tonsillar fossa and/or SP tumors. The rate at 10 years was 84% (BT group) vs. 78% (surgery group). However, adverse late side effects were not negligible. In addition to modality-specific side effects (ulcer/trismus), both treatment groups were significantly affected by xerostomia. Only 6 recurrences (4%) were observed in the 149 electively treated contralateral necks, and no relapses were seen in the 29 untreated contralateral necks. We, therefore, suggest that it is not necessary to treat the contralateral neck, unless the tumor extends beyond the midline of the soft palate (uvula) or beyond the lateral one-third of the ipsilateral base of the tongue. Moreover, with the currently available CT-based neck level definitions, more conformal contours (i.e., tighter boundaries) around the clinical target volume can be designed. In this way, critical structures such as the temporomandibular joint and part of the pterygoid muscles can be avoided more easily. Also, when using highly conformal treatment techniques (e.g., intensity-modulated RT), one can further reduce the dose to the major salivary glands and oral mucosa. We believe these measures will lead to less trismus and less xerostomia.

[Brachytherapy in head and neck cancers]

Experience accumulated over several decades with radiation of Head and Neck tumours by irradiation has demonstrated the need for a high tumour dose to achieve local control. With external beam irradiation alone, it is difficult to spare adjacent normal tissues, resulting in undesirable late effects on the salivary glands, mandible, and muscles of mastication. Interstitial implantation is ideally suited to deliver a high dose limited to the volume of the primary tumor, thus minimizing sequels. A large experience has been accumulated with low dose rate (LDR) brachytherapy in treatment of carcinoma of oral cavity, oropharynx, and nasopharynx. Recent analysis of large clinical series provided data indicating that modalities of low dose rate brachytherapy should be optimized in treating these tumors for increasing therapeutic ratio. Low dose rate brachytherapy is now challenged by high dose rate (HDR) brachytherapy and pulsed dose rate (PDR) brachytherapy. Preliminary results obtained with these two last modalities are discussed regarding to those of low dose rate brachytherapy.

Head and neck brachytherapy

Experience accumulated over several decades in the treatment of head and neck tumors by irradiation has demonstrated the need for a high tumor dose to achieve local control. With external beam irradiation alone, it is difficult to spare adjacent normal tissues, resulting in undesirable late effects on the salivary glands, mandible, and muscles of mastication. Interstitial implantation is ideally suited to deliver a high dose limited to the volume of the primary tumor, thus maximizing tumor control while minimizing complications. A large experience has been accumulated with low dose rate (LDR) brachytherapy in treatment of carcinoma of oral cavity, oropharynx, and nasopharynx. Recent analysis of large clinical series provided data indicating that modalities of LDR brachytherapy should be optimized in treating these tumors for increasing therapeutic ratio. LDR brachytherapy is now challenged by high dose rate (HDR) brachytherapy and pulsed dose rate (PDR) brachytherapy. Preliminary results obtained with these 2 last modalities will be discussed.

Radiation therapy for squamous cell carcinoma of the tonsillar region: a preferred alternative to surgery?

PURPOSE

There are no definitive randomized studies that compare radiotherapy (RT) with surgery for tonsillar cancer. The purpose of this study was to evaluate the results of RT alone and RT combined with a planned neck dissection for carcinoma of the tonsillar area and to compare these data with the results of treatment with primary surgery.

PATIENTS AND METHODS

Four hundred patients were treated between October 1964 and December 1997 and observed for at least 2 years. One hundred forty-one patients underwent planned neck dissection, and 18 patients received induction (17 patients) or concomitant (one patient) chemotherapy.

RESULTS

Five-year local control rates, by tumor stage, were as follows: T1, 83%; T2, 81%; T3, 74%; and T4, 60%. Multivariate analysis revealed that local control was significantly influenced by tumor stage (P =.0001), fractionation schedule (P =.0038), and external beam dose (P =.0227). Local control after RT for early-stage cancers was higher for tonsillar fossa/posterior pillar cancers than for those arising from the anterior tonsillar pillar. Five-year cause-specific survival rates, by disease stage, were as follows: I, 100%; II, 86%; III, 82%; IVa, 63%; and IVb, 22%. Multivariate analysis revealed that cause-specific survival was significantly influenced by overall stage (P =.0001), planned neck dissection (P =.0074), and histologic differentiation (P =.0307). The incidence of severe late complications after treatment was 5%.

CONCLUSION

RT alone or combined with a planned neck dissection provides cure rates that are as good as those after surgery and is associated with a lower rate of severe complications.

Curved angiocatheter metal guide for the implantation in velo-tonsillar carcinomas

Brachytherapy in velo-tonsillar region is not applied in all the institutions because of difficulties to learn it. For the implantation of wires in the soft palate, the Reverdin needle is replaced by a curved guide of angiocatheter 14 Gauge. This technique is easy and reduces the risk of tear mucosa.

Ipsilateral irradiation for carcinomas of tonsillar region and soft palate based on computed tomographic simulation

PURPOSE

To reduce xerostomia in selected patients with carcinomas of the tonsillar region and soft palate.

METHODS AND MATERIALS

We evaluated the treatment results of 32 patients with tonsillar region and soft palate carcinoma treated by radical radiotherapy between May 1989 and December 1996. They have a unilateral tumor that did not cross midline and have no contralateral neck lymphnode metastasis and treated with an ipsilateral technique (an anterior oblique and a posterior oblique field). All patients were planned with computed tomographic (CT) simulation and given 65 Gy in 26 fractions in 6.5 weeks with or without 5-15 Gy boost irradiation. The median follow-up was 44 months (4-86 months).

RESULTS

Five-year overall, cause-specific survival, local control, and regional control rate was 64, 79, 74 and 81%. No failure at the contralateral neck occurred. Moderate or severe symptomatic xerostomia was seen in 3 (9%) patients and ostero-radionecrosis requiring surgery occurred in one (3.3%) of 32 patients.

CONCLUSION

It is suggested that the ipsilateral technique is indicated in patients who had an unilateral tonsillar region or soft palate carcinoma that did not cross midline and have no contralateral neck lymphnode metastasis.

Surgical management of head and neck cancer

Head and neck cancer surgery continues to evolve through the years and undergo improvement and refinement. In this article, the current state of head and neck cancer surgery is summarized in a site-by-site basis. The most important developments include organ-sparing surgery and microvascular free-tissue transfer for reconstruction.

Feasibility and tolerance of pulsed dose rate interstitial brachytherapy

PURPOSE

Pulsed dose rate (PDR) treatment is a new approach that associates the physical advantages of high-dose-rate (HDR) technology with the potential radiobiological advantages of low-dose-rate (LDR) brachytherapy. This retrospective study analyzes the feasibility, toxicity, and preliminary oncologic results in a series of 43 patients treated with PDR interstitial brachytherapy.

METHODS AND MATERIALS

Twenty-four patients with pelvic, 17 patients with head and neck, and 2 patients with breast cancers were treated. Twenty-eight patients had primary and 15 recurrent tumors; 14 had received prior external irradiation to the same site. The doses per pulse at the prescription isodose were 0.4-1 Gy (median 0.5 Gy), delivered using a single cable-driven 0.3-1.0 Ci 192-iridium source (PDR Nucletron Micro-Selectron).

RESULTS

The median treated volumes (at the prescribed isodose) were 28 cc for pelvic, 8.33 cc for head and neck, and 40 cc for breast malignancies. Of 14,499 source and 14,499 dummy source transfer procedures, 3 technical machine failure events were observed (0.02%). Grade 3 acute toxicities were seen in 5/43 patients (4 oral stomatitis, 1 vaginal mucositis) and grade 4 acute toxicity in one patient (rectovaginal fistula). Grade 3-4 late complications were observed in 4/41 (9.8%) patients: 1 pubic fracture, 1 rectovaginal fistula, 1 vesicovaginal fistula and 1 local necrosis. With a median follow-up of 18 months, 10/41 patients progressed locoregionally (6 pelvic, 4 head and neck), 3 developed local recurrence and distant metastasis (3 pelvic), 3 only distant metastasis (2 pelvic, 1 head and neck). Two patients are lost to follow-up.

CONCLUSION

PDR interstitial brachytherapy for pelvic, head and neck, and breast malignancies is feasible and the acute and late toxicities seem acceptable. Although the physical advantages of PDR are clear, further follow-up is required to determine how results compare with those obtained with standard LDR brachytherapy.

[Virtual simulation. First clinical results in patients with prostate cancer]

AIM

Investigation of options of virtual simulation in patients with localized prostate cancer.

PATIENTS AND METHODS

Twenty-four patients suffering from prostate cancer were virtual simulated. The clinical target volume was contoured and the planning target volume was defined after CT scan. The isocenter of the planning target volume was determined and marked at patient's skin. The precision of patients marking was controlled with conventional simulation after physical radiation treatment planning.

RESULTS

Mean differences of the patient's mark revealed between the 2 simulations in all room axes around 1 mm. The organs at risk were visualized in the digital reconstructed radiographs.

CONCLUSIONS

The precise patient's mark of the isocentre by virtual simulation allows to skip the conventional simulation. The visualisation of organs at risk leeds to an unnecessarily of an application of contrast medium and to a further relieve of the patient. The personal requirement is not higher in virtual simulation than in conventional CT based radiation treatment planning.

Treatment duration as a prognostic factor for local control and survival in epidermoid carcinomas of the tonsillar region treated by combined external beam irradiation and brachytherapy

PURPOSE

We wanted to study the influence of the time factor in a combination of external irradiation and brachytherapy from a retrospective study of 370 squamous cell carcinomas of soft palate and tonsil.

PATIENTS AND METHODS

From 1977 to 1993, 370 soft palate and tonsillar carcinomas were treated at the Centre Alexis Vautrin. All patients received external irradiation (ERT) with a minimum dose to the tumour of 45 Gy, followed by low dose rate brachytherapy by Iridium 192 using the technique of plastic tubes; 22 patients received neo-adjuvant chemotherapy. We treated 85 T1, 159 T2, 117 T3 and nine T4 or TX carcinomas; 128 of these had palpable nodes. There were 267 men and 24 women. The median age was 55 years (range 33-81 years).

RESULTS

The median duration of the total treatment was 57 days. The rate of local control was 88% at 5 years when the treatment time was 7 weeks and 74% when it was 9 weeks (P = 0.001). The rates of overall survival at 5 years were 63 and 44%, respectively (P < 0.0001). For the interval between external irradiation and brachytherapy the series was divided into three groups, i.e. patients treated with a delay inferior or equal to 16 days (2 weeks), patients for which the interval was between 16 and 20 days and patients treated with a delay greater than 20 days (3 weeks). The rates of local control and overall survival at 5 years were not significantly different in the two first groups so we amalgamated these two groups and compared them with the third group. In this way the time cut-off for the delay between external irradiation and brachytherapy was 20 days. At 5 years, the rate of local control was 85% for the group for which the interval was inferior to 3 weeks and 73% when the delay was greater (P = 0.01). The rates of overall survival at 5 years were 59 and 38%, respectively (P < 0.001). Multivariate analysis confirmed that protraction of treatment was a factor for poorer local control. This factor was independent of the other prognostic factors.

CONCLUSION

The total duration of irradiation and the delay between external irradiation and brachytherapy were significant prognostic factors for local control and overall survival of soft palate and tonsil carcinomas. The overall duration should not be greater than 7 weeks (external irradiation, 5 weeks plus a delay of 12-15 days between ERT and brachytherapy). The delay should never be greater than 20 days, but a boost should be considered to make up for the loss of local control.

Fractionated high-dose-rate and pulsed-dose-rate brachytherapy: first clinical experience in squamous cell carcinoma of the tonsillar fossa and soft palate

PURPOSE

Fractionated high-dose-rate (fr.HDR) and pulsed-dose-rate (PDR) brachytherapy (BT) regimens, which simulate classical continuous low-dose-rate (LDR) interstitial radiation therapy (IRT) schedules, have been developed for clinical use. This article reports the initial results using these novel schedules in squamous cell carcinoma (SCC) of the tonsillar fossa (TF) and/or soft palate (SP).

METHODS AND MATERIALS

Between 1990 and 1994, 38 patients with TF and SP tumors (5 T1, 22 T2, 10 T3, and 1 T4) were treated by fr.HDR or PDR brachytherapy, either alone or in combination with external irradiation (ERT). Half of the patients were treated with fr.HDR, which entailed twice-daily fractions of > or = 3 Gy. The other 19 patients were administered PDR, which consisted of pulses of < or = 2 Gy delivered 4-8 times/day. The median cumulative dose of IRT +/- ERT series was 66 Gy (range 55-73). The results in these patients treated by brachytherapy were compared to 72 patients with similar tumors treated in our institute with curative intent, using ERT alone. The median cumulative dose of ERT-only series was 70 Gy (range 40-77).

RESULTS

Excellent locoregional control was achieved with the use of IRT +/- ERT, with only 13% (5 of 38) developing local failure, and salvage surgery being possible in three of the latter (60%). Neither BT scheme (fr.HDR vs. PDR) nor tumor site (TF vs. SP) significantly influenced local control rates. The type and severity of the side effects observed are comparable to those reported in the literature for LDR-IRT. These results contrast sharply with our ERT-only series, in which 39% of patients (28 of 72) developed local failure, with surgical salvage being possible only in three patients (11%). Taking the data set of 110 patients, in a univariate analysis IRT, T stage, N stage, overall treatment time (OTT), and BEDcor10 (biological effective dose with a correction for the OTT) were significant prognostic factors for local relapse-free survival (LRFS) and overall survival (OS) at 3 years. Using Cox proportional hazard analysis, only T stage and BEDcor10 remained significant for LRFS (p < 0.001 and 0.008, respectively), as well as for OS (p < 0.001 and 0.003, respectively). With regard to the current (IRT) and historical (ERT) series, for the LRFS at 3 years, dose-response relationships were established, significant, however, only for the BEDcor10 (p = 0.03).

CONCLUSION

The 3-year LRFS of approximately 90% for TF and SP tumors reported here is comparable with the best results in the literature, particularly given the fact that 30% of the patients (11 of 38) presented with T3/4 tumors. When compared with our historical (ERT-only) controls, the patients treated with IRT had superior local control. A dose-response relationship was established for the BEDcor10.

Continuous, pulsed or single acute irradiation of a transplanted rodent tumour model

BACKGROUND

Recent advances in remote afterloading pulsed mode brachytherapy have provided a much needed tool for the radiation oncologist. It has the versatility of optimised physical dose distribution along with improved staff radiation protection and patient nursing.

PURPOSE

This preliminary study was designed to explore the radiobiological equivalence between conventional continuous low dose rate tumour irradiation (CLDR) and the new technique of pulsed dose irradiation (PDR).

MATERIALS AND METHODS

Subcutaneous isogenic sarcomas transplanted in female John's Strain Wistar rats were irradiated locally with acute, pulsed or continuous interstitial low dose-rate exposures at 9-11 mm mean diameter.

RESULTS

As expected, single acute doses (5-40 Gy) were more effective (P < 0.01) in achieving tumour growth delay (1.4 days/Gy) than CLDR exposure (4-51 Gy) over 24-48 h (0.93 days/Gy). However, PDR treatment (8 hourly fractions/day) at high dose-rate (8-48Gy) over 8-72 h was significantly (P = 0.01) more effective (1.66 days/Gy) than CLDR but not acute exposures.

CONCLUSIONS

These data suggest that, clinically a significantly improved therapeutic ratio may also be achievable with pulsed high dose rate brachytherapy, and that further radiobiological studies with in-vivo tumour models are needed.

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.