Treatment of squamous cell anal canal carcinoma with pulsed dose rate brachytherapy. Feasibility study of a French cooperative group

Impact of Definitive Chemoradiation on Quality-of-Life Changes for Patients With Anal Cancer: Long-term Results of a Prospective Study

BACKGROUND

Maintaining and improving quality of life (QOL) are important goals of anal cancer management. This disease is generally curable, with many long-term survivors.

OBJECTIVE

Long-term QOL after chemoradiation for patients with anal cancer was evaluated.

DESIGN

This was a prospective cohort study.

SETTINGS

This study used data from a prospective study of patients with anal cancer who were treated with chemoradiation between 2008 and 2013.

PATIENTS

Patients with anal cancer who were treated with image-guided intensity-modulated radiation therapy were included.

INTERVENTIONS

English-speaking patients completed European Organization for Research and Treatment of Cancer cancer-specific (C30) and site-specific (CR29) QOL questionnaires at baseline, at end of radiation, at 3 and 6 months, and then annually.

MAIN OUTCOMES MEASURES

Long-term QOL was evaluated clinically (a change in score of ≥10 points was considered clinically significant) and statistically (using repeated-measurement analysis) by comparing the subscale scores at 1, 2, and 3 years with baseline scores. Subanalysis compared patients who received a radiation dose of 45 to 54 Gy versus 63 Gy.

RESULTS

Ninety-six patients were included (median follow-up of 56.5 months). The symptom and functional scales showed a clinically significant decline at the end of treatment with improvement by 3 months after treatment. There was a long-term statistically significant decline in dyspnea, body image, bowel embarrassment, fecal incontinence, and hair loss, and there was long-term statistically and clinically significant worsening of impotence. Higher radiation dose (63 Gy) was not associated with significantly worse QOL.

LIMITATIONS

Limitations included single-institution, single-arm study design, and lack of dose reconstruction (ie, analyses were based on prescribed, rather than delivered, dose).

CONCLUSIONS

Patients with anal cancer treated with chemoradiation reported recovery of overall QOL to baseline levels. Specific symptoms remained bothersome, emphasizing the need to address and manage the chemoradiation-induced symptoms, during treatment and in the long term. See Video Abstract at http://links.lww.com/DCR/B905.

IMPACTO DE LA QUIMIORRADIACIN DEFINITIVA EN CAMBIOS EN LA CALIDAD DE VIDA DE LOS PACIENTES CON CNCER ANAL RESULTADOS A LARGO PLAZO DE UN ESTUDIO PROSPECTIVE

ANTECEDENTES:Mantener y mejorar la calidad de vida son objetivos importantes del tratamiento del cáncer anal, ya que esta enfermedad generalmente es curable, con muchos sobrevivientes a largo plazo.OBJETIVO:Se evaluó la calidad de vida a largo plazo después de la quimiorradiación en pacientes con cáncer anal.DISEÑO:Este fue un estudio de cohorte prospectivo.ENTORNO CLINICO:Utilizamos datos de un estudio prospectivo en pacientes con cáncer anal tratados con quimiorradiación entre 2008-2013.PACIENTES:Los pacientes con cáncer anal fueron tratados con radioterapia de intensidad modulada guiada por imágenes.INTERVENCIONES:Los pacientes de habla inglesa completaron los cuestionarios de calidad de vida específicos de cáncer (C30) y específicos del sitio (CR29) de la Organización Europea para la Investigación y el Tratamiento del Cáncer al inicio, al final de la radiación, 3 y 6 meses, y luego anualmente.PRINCIPALES MEDIDAS DE RESULTADOS:Se evaluó a largo plazo la calidad de vida clínicamente (un cambio en la puntuación de ≥10 puntos se consideraron clínicamente significativo) y estadísticamente (usando análisis de medición repetida) comparando las subescalas de puntuación al 1, 2, y 3 años. Con puntuaciones de referencia. El subanálisis comparó pacientes que recibieron 45-54 Gy versus 63 Gy.RESULTADOS:Se incluyeron un total de 96 pacientes (mediana de seguimiento: 56,5 meses). La mayoría de las escalas funcionales y de síntomas mostraron una disminución clínicamente significativa al final del tratamiento con una mejoría a los 3 meses posteriores al tratamiento. Hubo una disminución estadísticamente significativa a largo plazo en disnea, imagen corporal, vergüenza intestinal, incontinencia fecal y pérdida de cabello; y hubo un empeoramiento a largo plazo estadística y clínicamente significativo en impotencia. La dosis de radiación más alta (63 Gy) no se asoció con una calidad de vida significativamente peor.LIMITACIONES:Institución única, diseño de estudio de un solo brazo y falta de recomposición de la dosis (es decir, los análisis se basan en la dosis prescrita, en lugar de la administrada).CONCLUSIÓNES:Los pacientes con cáncer anal tratados con quimiorradiación reportaron una recuperación de la QOL en general a los niveles de base. Síntomas específicos siguieron siendo molestos, lo que enfatiza la necesidad de resolver y tartar los síntomas inducidos por la quimiorradiación no solo durante el tratamiento, sino a largo plazo. Consulte Video Resumen en http://links.lww.com/DCR/B905. (Traducción- Dr. Francisco M. Abarca-Rendon).

Systematic review of the quality of life issues associated with anal cancer and its treatment with radiochemotherapy

PURPOSE

Radiochemotherapy is the standard of care for the treatment of anal carcinoma achieving good loco-regional control and sphincter preservation. This approach is however associated with acute and late toxicities including haematological, skin, bowel function and genito-urinary complications. This paper systematically reviews studies addressing the quality of life (QoL) implications of anal cancer and radiochemotherapy. The paper also evaluates how QoL is assessed in anal cancer.

METHODS

Medline, EMBASE, CINAHL, PsycInfo, Web of Science and the Cochrane Library were searched for publications (1996-2014) reporting the effects on patients of anal cancer and radiochemotherapy.

RESULTS

Of the 152 papers reporting treatment-related effects on patients, only 11 provided a formal assessment of QoL. In the absence of an anal cancer-specific measure, QoL was assessed using generic cancer instruments such as the core EORTC quality of life questionnaire (EORTC QLQ-C30) or colorectal cancer tools such as the EORTC QLQ-CR29. Bowel function, particularly diarrhoea, and sexual problems were the most commonly reported QoL concerns. The review of QoL issues of anal cancer patients treated with radiochemotherapy is limited by the QoL assessment measures used. It is argued that certain treatment-related toxicities, for example skin-induced radiation problems, are overlooked or inadequately represented in existing measures.

CONCLUSIONS

This review emphasises the need to develop an anal cancer-specific QoL measure and to incorporate QoL as an outcome of future trials in anal cancer. The results of this review are informative to clinicians and patients in terms of treatment decision-making.

A review of the clinical experience in pulsed dose rate brachytherapy

Pulsed dose rate (PDR) brachytherapy is a treatment modality that combines physical advantages of high dose rate (HDR) brachytherapy with the radiobiological advantages of low dose rate brachytherapy. The aim of this review was to describe the effective clinical use of PDR brachytherapy worldwide in different tumour locations. We found 66 articles reporting on clinical PDR brachytherapy including the treatment procedure and outcome. Moreover, PDR brachytherapy has been applied in almost all tumour sites for which brachytherapy is indicated and with good local control and low toxicity. The main advantage of PDR is, because of the small pulse sizes used, the ability to spare normal tissue. In certain cases, HDR resembles PDR brachytherapy by the use of multifractionated low-fraction dose.

Interstitial pulsed-dose-rate brachytherapy for the treatment of squamous cell anal carcinoma: A retrospective single institution analysis

OBJECTIVE

To examine the outcome of patients receiving interstitial pulsed-dose-rate brachytherapy (PDR-BT) after pelvic radiation therapy for treatment of an anal squamous cell carcinoma.

METHODS AND MATERIALS

Twenty-one patients were identified: 13, six, and two with stages I, II, and III tumors, respectively. After receiving received pelvic irradiation +/- concurrent chemotherapy, patients were delivered a PDR-BT boost to the residual tumor, with intention to deliver a minimal total dose of 60 Gy. The greatest dimension of residual tumor at the time of brachytherapy procedure was 12.5 mm (range: 0-20 mm). Brachytherapy implantation was performed according to the Paris system, only one plane implant being used.

RESULTS

Median dose delivered through BT was 20 Gy (range: 10-30 Gy). Median number of pulses was 48 (range: 20-80 pulses). Median treated volume was 9 cm(3) (range: 5-16 cm(3)). Median dose per pulse was 40 cGy (range: 37.5-50 cGy). No Grade 3 or more acute toxicity was reported. No Grade 3 or more delayed toxicity was seen among 18 patients with more than 6 months follow-up. Median followup was 47 months (range: 6-73 months). Twenty patients (95%) were alive at last follow-up. Tumor relapses were experienced in four patients (19%), including local relapse in three patients (14%).

CONCLUSION

With almost 4 years median followup, this study confirms previous data suggesting that PDR-BT is effective and safe in this indication. Local control rate and toxicity were in the range of what was seen with continuous low-dose-rate BT.

Interstitial high-dose rate brachytherapy as boost for anal canal cancer

AIM

To assess clinical outcomes of patients treated with a high-dose rate brachytherapy boost for anal canal cancer (ACC).

METHODS

From August 2005 to February 2013, 28 patients presenting an ACC treated by split-course external beam radiotherapy (EBRT) and HDR brachytherapy with or without chemotherapy in a French regional cancer center in Nice were retrospectively analyzed.

RESULTS

Median age was 60.6 years [34 - 83], 25 patients presented a squamous cell carcinoma and 3 an adenocarcinoma; 21 received chemotherapy. Median dose of EBRT was 45 Gy [43.2 - 52]. Median dose of HDR brachytherapy was 12 Gy [10 - 15] with a median duration of 2 days. Median overall treatment time was 63 days and median delay between EBRT and brachytherapy was 20 days. Two-year local relapse free, metastatic free, disease free and overall survivals were 83%, 81.9%, 71.8% and 87.7% respectively. Acute toxicities were frequent but not severe with mostly grade 1 toxicities: 37% of genito-urinary, 40.7% of gastro-intestinal and 3.7% of cutaneous toxicities. Late toxicities were mainly G1 (43.1%) and G2 (22%). Two-year colostomy-free survival was 75.1%, one patient had a definitive sphincter amputation.

CONCLUSION

High-dose rate brachytherapy for anal canal carcinoma as boost represents a feasible technique compared to low or pulsed-dose rate brachytherapy. This technique remains an excellent approach to precisely boost the tumor in reducing the overall treatment time.

Twenty-year experience in the management of squamous cell anal canal carcinoma with interstitial brachytherapy

OBJECTIVES

The aim of this study was to retrospectively evaluate clinical characteristics, local control, acute and late toxicity, and prognostic factors of patients with anal canal carcinoma treated with brachytherapy.

METHODS

From 1989 to 2009, 38 patients were treated with iridium 192 low-dose-rate (N = 26) or pulsed-dose-rate (N = 12) interstitial brachytherapy at a single institution. The median age was 62 years (range, 38-86 years). The TNM classification was as follows: 10 T1, 22 T2, 5 T3 and 1 T4; 32 N0, 3 N1 and 3 N2. Most patients (32/38) received either a first course of radiochemotherapy (N = 22) or radiotherapy alone (N=10) consisting of a total delivered dose of 45 Gy to the pelvis (range, 32-50) followed by a boost a median of 18 days later of 15-35 Gy (median 20 Gy) to the anal canal. The remaining 6 cases were treated with brachytherapy alone (dose range, 60-65 Gy).

RESULTS

With a median follow-up of 30 months (range, 4-200), 2- and 5-year local control rates were 91% and 87%, respectively. Preservation of the anal sphincter was achieved in 32 patients (84%). Three patients experienced incontinence after brachytherapy. Only 2 patients showed chronic mucositis grade 3/4. Age proved to be a statistically significant prognostic factor for overall survival in the univariate (p = 0.033) and multivariate analyses (p = 0.018). Concurrent chemotherapy with external beam radiotherapy was a statistically significant prognostic factor for disease-free survival in the univariate and multivariate analyses (p = 0.007 and p = 0.044, respectively).

CONCLUSIONS

Interstitial brachytherapy appears to be an effective and well tolerated treatment for anal carcinoma offering both high local tumour control and anal sphincter preservation.

Pulsed dose rate brachytherapy - is it the right way?

Pulsed dose rate (PDR-BT) treatment is a brachytherapy modality that combines physical advantages of high-dose-rate (HDR-BT) technology (isodose optimization, radiation safety) with the radiobiological advantages of low-dose-rate (LDR-BT) brachytherapy. Pulsed brachytherapy consists of using stronger radiation source than for LDR-BT and producing series of short exposures of 10 to 30 minutes in every hour to approximately the same total dose in the same overall time as with the LDR-BT. Modern afterloading equipment offers certain advantages over interstitial or intracavitary insertion of separate needles, tubes, seeds or wires. Isodose volumes in tissues can be created flexibly by a combination of careful placement of the catheter and the adjustment of the dwell times of the computerized stepping source. Automatic removal of the radiation sources into a shielded safe eliminates radiation exposures to staff and visitors. Radiation exposure is also eliminated to the staff who formerly loaded and unloaded multiplicity of radioactive sources into the catheters, ovoids, tubes etc. This review based on summarized clinical investigations, analyses the feasibility and the background to introduce this brachytherapy technique and chosen clinical applications of PDR-BT.

Pulsed dose rate brachytherapy

Pulsed dose rate (PDR) is a new modality for dose delivery in brachytherapy. It uses modern afterloading technology (miniaturized source, cable driven, software controlled), with source activities in the range of 1 Ci, which is actually one tenth of the normal activity used for high dose rate (HDR) brachytherapy. Modern technology allows dose optimization, and source strength in the above-mentioned range creates a new dose rate condition. For small fractions (pulses) with short interpulse intervals, PDR mimics the radiobiology of high dose rate brachytherapy, whereas for bigger doses per fraction, dose adjustments are needed to compensate for the loss of therapeutic ratio. Clinical series showed good figures for local control and toxicity. Almost every clinical site has been reported to have been treated with PDR, with some thousand of patients having been reported. Technical difficulties in some body sites can be overcome by slightly modifying the implant technique. PDR brachytherapy is an ideal environment for the development of new dose fractionation schedules. It creates unique conditions in which to operate. Knowledge of tissue repair kinetics is extremely important for adequate selection of dose per pulse and interpulse interval. Therapeutic ratio can be improved by adjusting interpulse intervals to the repair half-times for normal tissues. On the other hand, superfractionated schedules with low dose per pulse can be explored in conditions of tumor hypoxia, thanks to the predicted hypersensitivity at low dose per fraction. The use of chemical agents (nicotinamide and others) in concomitance with this superfractionated schedules is foreseen in controlled clinical trials. In conclusion, PDR brachytherapy can be considered a new paradigm for dose delivery. It is safe and reliable, can be used in the setting of image-guided radiation therapy, and exploit the differential effect of ionizing radiations by a thorough knowledge of tissue kinetics for an improved therapeutic ratio.

Radiation dose associated with local control in advanced anal cancer: retrospective analysis of 129 patients

BACKGROUND AND PURPOSE

To retrospectively analyse a large consecutive cohort of patients with anal cancer for treatment-related factors influencing local control and survival.

MATERIALS AND METHODS

All patients referred for primary radiotherapy at Medical University of Vienna in 1990-2002 with anal canal carcinoma without distant metastases were analysed. Treatment consisted of external radiotherapy with or without brachytherapy and with or without chemotherapy. Patient-, tumour-, and treatment-factors were tested for influence on survival and local control using Cox multivariate analysis.

RESULTS

Median age was 67 years (n=129), the UICC stage distribution was 15%, 58%, and 27% for stages I, II, and III, respectively. With median follow-up of 8.0 years for surviving patients (3.9 years including deceased patients), five-year overall survival and disease-free-survival were 57% and 51%, respectively. Local control at 5 years was 87%. Stage and age were significant factors for overall and colostomy-free-survival, N-stage for disease-free-survival. Shorter overall treatment time favoured local control in stage T1-2 (p=.015), higher total radiation dose and female gender were associated with improved local control in T3-4 tumours (p=.021).

CONCLUSIONS

These results support potential improvement of anal cancer treatment by studying advanced technology such as IMRT, making it possible to tailor high-dose regions.

Safety aspects of pulsed dose rate brachytherapy: analysis of errors in 1,300 treatment sessions

PURPOSE

To determine the safety of pulsed-dose-rate (PDR) brachytherapy by analyzing errors and technical failures during treatment.

METHODS AND MATERIALS

More than 1,300 patients underwent treatment with PDR brachytherapy, using five PDR remote afterloaders. Most patients were treated with consecutive pulse schemes, also outside regular office hours. Tumors were located in the breast, esophagus, prostate, bladder, gynecology, anus/rectum, orbit, head/neck, with a miscellaneous group of small numbers, such as the lip, nose, and bile duct. Errors and technical failures were analyzed for 1,300 treatment sessions, for which nearly 20,000 pulses were delivered. For each tumor localization, the number and type of occurring errors were determined, as were which localizations were more error prone than others.

RESULTS

By routinely using the built-in dummy check source, only 0.2% of all pulses showed an error during the phase of the pulse when the active source was outside the afterloader. Localizations treated using flexible catheters had greater error frequencies than those treated with straight needles or rigid applicators. Disturbed pulse frequencies were in the range of 0.6% for the anus/rectum on a classic version 1 afterloader to 14.9% for orbital tumors using a version 2 afterloader. Exceeding the planned overall treatment time by >10% was observed in only 1% of all treatments. Patients received their dose as originally planned in 98% of all treatments.

CONCLUSIONS

According to the experience in our institute with 1,300 PDR treatments, we found that PDR is a safe brachytherapy treatment modality, both during and outside of office hours.

External beam radiotherapy plus brachytherapy boost in treatment of anal canal carcinoma

Purpose: Radiotherapy has been the standard treatment of anal canal carcinoma for the last three decades. However, there are still many open questions such as optimal radiation technique, adequate boost dose or best chemotherapy regimen. Beside cure and local control, other important goals are sphincter salvage and avoidance of a permanent colostomy, i.e. morbidity minimization. Material and methods: At the Institute for Oncology and Radiology of Serbia, between March 1997 and May 2004, patients with anal canal carcinoma were treated with combined external beam radiotherapy and brachytherapy boost as primary treatment modality. Initially, external beam radiotherapy was applied with two opposed parallel fields and dose ranged from 40-50 Gy and after that patient continued the treatment with brachytherapy boost (intraluminal or interstitial) with doses ranged from 10-25 Gy. Total tumor dose in combined radiotherapy treatment ranged from 55-70 Gy. Results: Out of 21 patients, acute complications were registered in 15 patients (71.4%) and the most frequent was dermatitis. Complete response after radiotherapy was registered in 17 patients (81%). In the median follow up time of 42 months, five-year overall survival was 71% and disease free survival was 61%. Late sequelas were registered in 14 patients (66.7%), but they were low grade. Conclusions: Our study shows results using external beam radiotherapy and brachytherapy boost as single modality treatment, but we need more randomized trial to improve better local control and minimize toxicity.

Treatment of squamous cell anal canal carcinoma (SCACC) with pulsed dose rate brachytherapy: A retrospective study

BACKGROUND AND PURPOSE

To evaluate the results of pulsed dose rate brachytherapy (PDR) in SCACC.

MATERIAL AND METHODS

From 1996 to 2002, 71 patients (pts) with SCACC were treated with PDR brachytherapy. The median age was 61.2 years (35-88), with a sex ratio of 1 M/6.5 F. The TNM classification was: 14 T1, 41 T2, 15 T3 and 1 T4, 52 N0, 13 N1, 3 N2 and 3 N3. All the pts were M0. Treatment started with external beam irradiation to the posterior pelvis (mean dose: 45.5 Gy). Forty-seven patients received chemotherapy (neoadjuvant/concomitant or both). After an interval of 2-6 weeks, PDR interstitial brachytherapy was performed. The mean dose was 17.8 Gy to the 85% reference isodose of the Paris system.

RESULTS

Treatment was interrupted in only one pt. With a median follow-up of 28.5 months, 2-year actuarial overall survival was 90%. Fourteen relapses occurred (four distant, three regional, and seven local). Ten patients developed a grade III complication (Lent Soma scale) and two a grade IV complication (colostomy or abdominal perineal resection for necrosis).

CONCLUSION

PDR appears to be an effective treatment for SCACC. It is capable of reproducing the results usually observed with continuous LDR.

Anal canal carcinoma: early-stage tumors < or =10 mm (T1 or Tis): therapeutic options and original pattern of local failure after radiotherapy

PURPOSE

To investigate the clinical history, management, and pattern of recurrence of very early-stage anal canal cancer in a French retrospective survey.

METHODS

The study group consisted of 69 patients with Stage Tis and T1 anal canal carcinoma < or =1 cm treated between 1990 and 2000 (12 were in situ, 57 invasive, 66 Stage N0, and 3 Stage N1). The median patient age was 67 years (range, 27-83 years). Of the 69 patients, 66 received radiotherapy (RT) and 3 with in situ disease were treated by local excision alone without RT. Twenty-six patients underwent local excision before RT (12 with negative and 14 with positive surgical margins). Of the 66 patients who underwent RT, 8 underwent brachytherapy alone (median dose, 55 Gy), 38 underwent external beam RT (median dose, 45 Gy) plus a brachytherapy boost (median boost dose, 20 Gy), and 20 underwent external beam RT alone (median dose, 55 Gy).

RESULTS

Of the 69 patients, 68 had initial local control. Of the 66 patients treated by RT, 6 developed local recurrence at a median interval of 50 months (range, 13-78 months). Four patients developed local failure outside the initial tumor bed. Of the 3 patients with Tis treated by excision alone, 1 developed local recurrence. No relation was found among prior excision, dose, and local failure. The 5-year overall survival, colostomy-free survival, and disease-free survival rate was 94%, 85%, and 89%, respectively. The rate of late complications (Grade 1-3) was 28% and was 14% for those who received doses <60 Gy and 37% for those who received doses of > or =60 Gy (p = 0.04).

CONCLUSION

Most recurrences occurred after a long disease-free interval after treatment and often outside the initial tumor site. These small anal cancers could be treated by RT using a small volume and moderate dose (40-50 Gy for subclinical lesions and 50-60 Gy for T1).

Chemotherapy and radiation of anal canal cancer: the first approach

Since the late 1970's, increasing evidence from single-arm phase II studies has indicated that combined modality therapy yields a complete response rate of approximately 80-90% in most patients with squamous cell cancers of the anal canal. Surgery, most commonly an abdominoperineal resection, is reserved for salvage therapy. Although patients with large primary tumors (>5 cm) have a lower complete response rate of 50-75%, the majority of patients may be spared a colostomy and have an excellent overall survival. This chapter reviews the recent literature of patients treated for squamous cell, basaloid, and cloacogenic carcinoma (collectively defined as squamous cell cancer) of the anal canal.

[Brachytherapy in carcinomas of anal canal and rectum: techniques and results]

Conservative treatment of small anal canal and low rectal cancers is a valid alternative to radical surgery through combinated strategies including external beam and/or intracavitary irradiation, concomitant chemotherapy and 192 iridium implantation as a booster dose. Feasibility, tolerance and results are effective. Local control of the disease and the quality of the anal functions are good. The treatment requires great care in patient selection and follow-up.

High-dose radiation therapy and neoadjuvant plus concomitant chemotherapy with 5-fluorouracil and cisplatin in patients with locally advanced squamous-cell anal canal cancer: final results of a phase II study

PURPOSE

To analyse toxicity and response to a new scheme of neoadjuvant chemotherapy (CT) and concomitant radiochemotherapy (RT-CT) for locally advanced anal canal squamous-cell carcinoma (ACC).

PATIENTS AND METHODS

Eighty patients with an ACC > 40 mm and/or with lymph node involvement were included (1 T1, 52 T2, 14 T3, 13 T4, 18 N0, 30 N1, 32 N2-N3). Two cycles of 5-fluorouracil (5-FU) and CDDP were delivered as neoadjuvant CT and two during RT-CT. Pelvic (+/- inguinal) RT delivered 45 Gy in 25 fractions of 1.8 Gy. Involved fields were boosted after a one to two month gap (15-20 Gy). The median follow-up was 29 months.

RESULTS

One patient died of a pulmonary embolism on day 4. All patients received the entire treatment, with reduced 5-FU doses in 27% of the cases because of acute toxicity. Sixty-four grade 3 and five grade 4 toxicities were observed. No toxic death occurred. Complete response (CR) and partial response (PR) rates were, respectively, 10% and 51% after neoadjuvant CT, 67% and 28% after RT-CT and 93% and 5% after treatment completion (including 4 abdomino-perineal resections). The three-year actuarial overall, tumour-specific, colostomy-free, relapse-free, disease-free and event-free survivals were 86%, 88%, 73%, 70%, 67% and 63%, respectively.

CONCLUSIONS

Tolerance was good. After neoadjuvant CT, most of the patients were objective responders. After treatment completion, all but five achieved CR. The long-term results confirm the durability of local control and low toxicity on the sphincter. An ongoing phase III intergroup trial analyses the impact of neoadjuvant CT, and the benefit of a high-dose boost irradiation, on local control and colostomy-free survival.

Pulsed dose rate brachytherapy in head and neck cancers. Feasibility study of a French cooperative group

PURPOSE

To prospectively evaluate the feasibility of pulsed dose rate (PDR) brachytherapy to mimic the continuous low dose rate (cLDR) iridium wire technique in head and neck carcinomas.

MATERIALS AND METHODS

A series of 30 patients were included from June 1995 to May 1998. The primaries were located in the oral cavity (four T1, seven T2 and two T3), the velotonsillar arch (eight T1 and eight T2) and the posterior wall (one T3). Thirteen were irradiated by exclusive brachytherapy (dose, > or =45 Gy). The PDR delivered 0.5 Gy/pulse, one pulse/h, day and night, to mimic cLDR irradiation.

RESULTS

The implantation was feasible for all the patients, usually easy and of good quality. The mean duration/pulse was 13 min, with a mean source activity of 171 mCi. Patient tolerance was poor in nine cases. Sixteen patients could receive the whole PDR treatment with a total ranging from 30 to 120 pulses without any problem. Seven had short breakdowns (< or =6 h). Seven had definitive breakdowns, but could end the irradiation by manual afterloading of iridium 192 wires. The radioprotection was better (or complete), except for one patient. Most of the breakdowns were related to kinking or flattering of the tube.

CONCLUSIONS

PDR is feasible in head and neck carcinomas, but necessitates improvement of the quality and control of the plastic tubes.