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121 A new strategy for intracavitary high dose rate brachytherapy on cervical cancer using MRI
121 A NEW STRATEGY FOR INTRACAVITARY HIGH DOSE RATE BRACHYTHERAPY ON CERVICAL CANCER USING M R I Kazuo Hatano I, Mitsuhiro Sakai I, Hitoshi Araki 1, Yoshihisa Akiyama ~, Yuichiro Narita t, Hisao Ito2 1 Div. of Radiation Oncology, Chiba Cancer Center, Chiba, Japan 2 Dept. of Radiology, Chiba University, School of Medicine, Chiba, Japan
Purpose: Both MRI and 3-D treatment planning system enabled us to detect tumor extension, tumor volume and to optimize and individualize the treatment volume using intracavitary HDR brachytherapy. This study is to evaluate the efficacy of MRl-based intracavitary HDR brachytherapy fol cervical cancer and re-evaluate the "Manchester System". Materials and methods: Thirty-two patients with newly diagnosed squamous cell carcinoma of the uterine cervix (FIGO Stage Ib: 5, lla: 2, lib: 11, Illb: 14) were treated with curative radiotherapy between May 1995 and October 1997. The median age at the time of treatment was 63.8 years (range 33-90 years). The median follow-up time was 39 months (range 9.5-60.5 months). All patients were treated with 30 Gy whole pelvic irradiation followed by 20 Gy boost to parametrium. At the first brachytherapy day, both CT and MRI were performed, using a CT-MR compatible applicator. The GTV (Gross Tumor Volume) was defined as a high signal intensity mass obtained from MRI. And then the CTV (Clinical Target Volume), which covered the GTV with 6Gy was calculated with PLATO system. So, the dose distribution is not a pear-shaped. Four and 5-year survival rates were calculated using Kaplan-Meier method, and late sequelae of the rectum and bladder were also evaluated. Results: Delineation of the macroscopic tumor on the MRI was possible in all patients. The average GTV was 18.2cm3 (range 2.8-85.2) and the average CTV was 66.8 cm 3 (range 26-135.5). The average point A dose was 557cGy (range 342-826). Five-year survival rate was 80% for stage Ib, 4-year survival rate was 85%, 71% for stage lib and lllb, respectively. Three patients had residual tumor after treatment. One of these received 4Gy boost-RALS and got local control, next patient was operated, and another patient refused further treatment and died of carcinomatous peritonitis. No local recurrence was observed during the follow-up period. Eleven patients (34%) showed complications consisting of rectal bleeding and hematuria. But all of them were Grade 1 and no patients showed severe complications more than Grade 2 at 5 years. Conclusion: We can optimize and individualize the dose distribution according to the GTV which was defined as high signal intensity mass obtained from MRI at the first brachytherapy day. Although the median follow-up time is too short and the number of the patients is too small to evaluate these results, the tumor control rate and the complication rate are good and are acceptable. More work to search for the optimum fractionated dose is needed. And the "Manchester system" should be re-evaluated with new methods. 122 PATTERNS OF FAILURE FOR CANCER OF THE VAGINA RELATED TO BOOST RADIATION TECHNIQUES AFTER EXTERNAL PELVIC RADIATION Sandra A. Tincher, M.D. and Robert Y. Kim, M.D. Department of Radiation Oncology, Comprehensive Cancer Center, University of Alabama at Birmingham, Birmingham, AL 35233 Purpose: The treatment of vaginal cancer usually consists of a combination of external beam radiation and brachytherapy. The most common sites of recurrence for vaginal cancer are the vagina and pelvis. This is a retrospective review to examine patterns of failure for patients treated with curative intent using various techniques for boost following external beam pelvic irradiation. Methods: Between 1972 and 1998, 27 patients were treated for primary vaginal cancer; six patients were excluded who were treated palliatively, one excluded for histology of sarcoma, and one was excluded due to less than 24 months of follow-up. Of the 19 remaining evaluable patients, the median age was 68 years (range 49-87 years). The median follow-up was 63.5 month. Eleven women were Caucasian and 8 were AfricanAmerican. Histology consisted of squamous cell carcinoma (15 patients) and adenocarcinoma (4 patients). There were 2 stage I patients, 11 stage II patients, and 6 stage 111patients. The 2 stage 1 patients received brachytherapy alone, one by LDR vaginal cylinder and one by HDR vaginal cylinder. The 17 patients with stage II-III disease received external beam radiotherapy to the pelvis and inguinals to a median dose of 47.7 Gy. Boost was delivered by vaginal cylinder in 5 patients: one by LDR and 4 by HDR, interstitial implant in 6 patients, and by shrinking field external beam technique without brachytherapy in 4 patients. Two patients did not receive any form of boost; one due to refusal of any further therapy and one due to development of distant metastatic disease. Results: The recurrence rate for patients with vaginal cancer treated with curative intent was 21% (4 local recurrences in 19 patients). There were no recurrences in the patients with stage I disease, both of which were treated with vaginal cylinder alone. For stage II/III disease, there were 2 recurrences in the 5 patients boosted with vaginal cylinder (40%), there was 1 recurrence in the 6 patients boosted with interstitial implant (16%) and there was 1 recurrence in the 4 patients boosted with shrinking field technique (25%). One recurrence was at the bladder neck and inguinal area in a Stage 111patient boosted by interstitial implant. The remaining three recurrences were in Stage II patients, one boosted with shrinking field technique and occurred in the ischial rectal fossa, two boosted with vaginal cylinder and occurred in the posterior vagina and inguinal areas. Conclusion: For Stage II/III vaginal cancer, the form of boost radiation after whole pelvic external beam which resulted in the fewest recurrences was interstitial implant. This was followed by shrinking field external beam technique for boost. Vaginal cylinder brachytherapy should be avoided in Stage ll/IIl patients even if there is a good gross response. 123 POST-OPERATIVE RADIOTHERAPY FOR ENDOMETRIAL CARCINOMA WITH PATHOLOGIC RISK FACTORS: PATTERNS OF FAILURE Lee CP, Chuba PJ, Deppe G, Tekyi-Mensah S, Hart I Gershenson Radiation Oncology Center, Barbara Ann Karmanos Cancer Institute, Detroit
Purpose: To examine the failure patterns
in patients treated with post-operative external beam radiotherapy and vaginal cuff brachytherapy for endometrial carcinoma. Design: Retrospective review from Wayne State University of endometrial carcinoma treated between 1980 and 1998. Materials and methods: 250 endometrial carcinoma patients were treated with hysterectomy followed by radiotherapy. Histologies included adenocarcinoma (n=184), adenosquamous (n=26), and others (n=40). Tumor grade was as follows: 35 well differentiated, 30 well to moderately
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Purpose: Both MRI and 3-D treatment planning system enabled us to detect tumor extension, tumor volume and to optimize and individualize the treatment volume using intracavitary HDR brachytherapy. This study is to evaluate the efficacy of MRl-based intracavitary HDR brachytherapy fol cervical cancer and re-evaluate the "Manchester System". Materials and methods: Thirty-two patients with newly diagnosed squamous cell carcinoma of the uterine cervix (FIGO Stage Ib: 5, lla: 2, lib: 11, Illb: 14) were treated with curative radiotherapy between May 1995 and October 1997. The median age at the time of treatment was 63.8 years (range 33-90 years). The median follow-up time was 39 months (range 9.5-60.5 months). All patients were treated with 30 Gy whole pelvic irradiation followed by 20 Gy boost to parametrium. At the first brachytherapy day, both CT and MRI were performed, using a CT-MR compatible applicator. The GTV (Gross Tumor Volume) was defined as a high signal intensity mass obtained from MRI. And then the CTV (Clinical Target Volume), which covered the GTV with 6Gy was calculated with PLATO system. So, the dose distribution is not a pear-shaped. Four and 5-year survival rates were calculated using Kaplan-Meier method, and late sequelae of the rectum and bladder were also evaluated. Results: Delineation of the macroscopic tumor on the MRI was possible in all patients. The average GTV was 18.2cm3 (range 2.8-85.2) and the average CTV was 66.8 cm 3 (range 26-135.5). The average point A dose was 557cGy (range 342-826). Five-year survival rate was 80% for stage Ib, 4-year survival rate was 85%, 71% for stage lib and lllb, respectively. Three patients had residual tumor after treatment. One of these received 4Gy boost-RALS and got local control, next patient was operated, and another patient refused further treatment and died of carcinomatous peritonitis. No local recurrence was observed during the follow-up period. Eleven patients (34%) showed complications consisting of rectal bleeding and hematuria. But all of them were Grade 1 and no patients showed severe complications more than Grade 2 at 5 years. Conclusion: We can optimize and individualize the dose distribution according to the GTV which was defined as high signal intensity mass obtained from MRI at the first brachytherapy day. Although the median follow-up time is too short and the number of the patients is too small to evaluate these results, the tumor control rate and the complication rate are good and are acceptable. More work to search for the optimum fractionated dose is needed. And the "Manchester system" should be re-evaluated with new methods. 122 PATTERNS OF FAILURE FOR CANCER OF THE VAGINA RELATED TO BOOST RADIATION TECHNIQUES AFTER EXTERNAL PELVIC RADIATION Sandra A. Tincher, M.D. and Robert Y. Kim, M.D. Department of Radiation Oncology, Comprehensive Cancer Center, University of Alabama at Birmingham, Birmingham, AL 35233 Purpose: The treatment of vaginal cancer usually consists of a combination of external beam radiation and brachytherapy. The most common sites of recurrence for vaginal cancer are the vagina and pelvis. This is a retrospective review to examine patterns of failure for patients treated with curative intent using various techniques for boost following external beam pelvic irradiation. Methods: Between 1972 and 1998, 27 patients were treated for primary vaginal cancer; six patients were excluded who were treated palliatively, one excluded for histology of sarcoma, and one was excluded due to less than 24 months of follow-up. Of the 19 remaining evaluable patients, the median age was 68 years (range 49-87 years). The median follow-up was 63.5 month. Eleven women were Caucasian and 8 were AfricanAmerican. Histology consisted of squamous cell carcinoma (15 patients) and adenocarcinoma (4 patients). There were 2 stage I patients, 11 stage II patients, and 6 stage 111patients. The 2 stage 1 patients received brachytherapy alone, one by LDR vaginal cylinder and one by HDR vaginal cylinder. The 17 patients with stage II-III disease received external beam radiotherapy to the pelvis and inguinals to a median dose of 47.7 Gy. Boost was delivered by vaginal cylinder in 5 patients: one by LDR and 4 by HDR, interstitial implant in 6 patients, and by shrinking field external beam technique without brachytherapy in 4 patients. Two patients did not receive any form of boost; one due to refusal of any further therapy and one due to development of distant metastatic disease. Results: The recurrence rate for patients with vaginal cancer treated with curative intent was 21% (4 local recurrences in 19 patients). There were no recurrences in the patients with stage I disease, both of which were treated with vaginal cylinder alone. For stage II/III disease, there were 2 recurrences in the 5 patients boosted with vaginal cylinder (40%), there was 1 recurrence in the 6 patients boosted with interstitial implant (16%) and there was 1 recurrence in the 4 patients boosted with shrinking field technique (25%). One recurrence was at the bladder neck and inguinal area in a Stage 111patient boosted by interstitial implant. The remaining three recurrences were in Stage II patients, one boosted with shrinking field technique and occurred in the ischial rectal fossa, two boosted with vaginal cylinder and occurred in the posterior vagina and inguinal areas. Conclusion: For Stage II/III vaginal cancer, the form of boost radiation after whole pelvic external beam which resulted in the fewest recurrences was interstitial implant. This was followed by shrinking field external beam technique for boost. Vaginal cylinder brachytherapy should be avoided in Stage ll/IIl patients even if there is a good gross response. 123 POST-OPERATIVE RADIOTHERAPY FOR ENDOMETRIAL CARCINOMA WITH PATHOLOGIC RISK FACTORS: PATTERNS OF FAILURE Lee CP, Chuba PJ, Deppe G, Tekyi-Mensah S, Hart I Gershenson Radiation Oncology Center, Barbara Ann Karmanos Cancer Institute, Detroit
Purpose: To examine the failure patterns
in patients treated with post-operative external beam radiotherapy and vaginal cuff brachytherapy for endometrial carcinoma. Design: Retrospective review from Wayne State University of endometrial carcinoma treated between 1980 and 1998. Materials and methods: 250 endometrial carcinoma patients were treated with hysterectomy followed by radiotherapy. Histologies included adenocarcinoma (n=184), adenosquamous (n=26), and others (n=40). Tumor grade was as follows: 35 well differentiated, 30 well to moderately
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