47 Results of hdr-brachytherapy combined with external beam therapy in the primary treatment of cervical carcinoma

cervix provides excellent treatment results, the same as LDR applications concerning survival data and complication rates as welt. Our results are matching with that of other authors very well. The method described above is a very effective tool for primary irradiation of cancer of the uterine cervix, and a safe one in experienced hands. 47 RESULTS OF HDR-BRACHYTHERAPY COMBINEDWITH EXTERNALBEAM THERAPY IN THE PRIMARY TREATMENTOF CERVICAL CARCINOMA T.H. Knocke, R. POtter Department for radiotherapy and radiobiology, University of Vienna, Austria Purpose: In the primary treatment of cervical carcinoma HDR-brachytherapy has now become an established alternative to LDR-brachytherapy. We report our results regarding disease specific survival, local control and late sequelae of this treatment option. Material and methods: From 11/93 to 12/97 189 patients were treated with a curative intent. Age ranged from 31 to 91 years (median 67 years). Two patients presented in stage la, Ib=l 1,lla=l 1, Ilb=78, Illa=19, Illb=58, 1Va=5 and 3 patients in stage IVb with enlarged paraaortic lymph nodes. Squamous cell carcinoma was found in 166 patients, adenocarcinoma in 16, adeno-squamous carcinoma in 5 and small cell carcinoma in two patients. Clinical tumor diameter ranged from 1-9cm (mean 5,5 cm). Radiotherapy was prescribed according to two different regimens: treatment schedule for smaller tumors started with intracervical brachytherapy (n=49). Five to six fractions of HDR-brachytherapy with single fractions of 7 Gy to point "A" in weekly intervals were applied. External beam therapy was given four days a week with a linear accelerator (25MV) with a four field box technique in 1.8-2 Gy fractions up to a total dose of 48.6 - 50 Gy. A central shielding was placed in a.p./p.a, portals from the beginning. Patients with larger tumors and patients where the tumor was not accessible for an initial brachytherapy started with external beam therapy (n=140) up to a dose of 48.6-50 Gy with a four field box technique to the pelvis or in case of enlarged lymph nodes in CT to paraaortic region as well (n=20). Brachytherapy was given after EBT with single fractions of 7 Gy to point "A" in weekly intervals 2-5 times (median 3). Brachytherapy was performed with a tandem-ring applicator. Treatment planning was based on isocentric X-rays and on CT with applicator in place. Limited adjustments of dose distributions were done when CT findings showed an underdosage of visible tumor or an overdosage at organs at risk. Overall in 30.2% of applications such adjustments were performed although dose to point "A" was not altered. Resulting volumes of the prescribed isodose ranged from 46 - 155 cm (median 87 ccm). Results: After a median follow-up of 34 months 108 patients were alive without evidence of disease, two patients are alive with recurrence and 58 patients have died due to tumor. One patient committed suicide and twenty patients have died of intercurrent disease (age 67-91 years, median 80 years). Calculated disease specific survival at 3 years was 68.6% for all patients, 100% in stage Ia, 77.1% in stage Ib, 100% in stage lla, 78.0% in stage lib, 52.1% in stage Ilia, 58.6% in stage IIib, 53.3% in stage 1Va and 0% in stage IVb. Actuarial pelvic control at 3 years was 77.6% for all patients, 100% in stages la, lb and lla, 87.0% in stage lib, 52.7% in stage llla, 69.1% in stage lllb and 60.0% in stage IVa. When comparing outcome for patients with initial tumor diameter less 5 cm (n=65) to larger tumors (n=124) pelvic control and disease specific survival at 3 years were 90.0%/90.7% and 67.4%/57.3%, respectively. According to the EORTC/RTOG score 25 grade 3 and 13 grade 4 late complications were observed in 24 patients. Of those the vast majority were stenosis or obliterations of the vagina (n=24). There were 3 grade 3+4 late sequelae at the bladder, 4 at small bowel and 7 at the rectum including five recto-vaginal fistulas. Conclusion: HDR-brachytherapy is an effective option for the primary treatment of cervical carcinoma, results and treatment related sequelae are comparable to those of LDR-brachytherapy. 48 SOLE HDR-BRACHYTHERAPY AFTER BREAST CONSERVINGSURGERY: 4 YEAR RESULTS OF A PILOT STUDYAND INITIALFINDINGSOF A RANDOMIZEDPHASE III TRIAL C. Polgar, T. Major, L.C. Mangel, Z. Takacsi-Nagy, A. Somogyi, Z. Sulyok*, J. Fodor, G. NEmeth National Institute of Oncology, Department of radiotherapy and surgery*, Budapest, Hungary Purpose: to evaluate the feasibility, cost effectiveness, local control and side effects of sole HDR-brachytherapy (BT) after breast conserving surgery (BCS) in a pilot study, and to initiate a randomized phase I11 trial to get evidence based results. Materials and methods: 1.45 prospectively selected patients with pT1 pN0-I a breast cancer were entered into a pilot study protocol of tumor bed irradiation using interstitial HDR implants. At 8 patients 7 x 4.33 Gy, at 37 ones 7 x 5.2 Gy was delivered to the tumor bed with 2 cm margin. The treatment planning was based on the 3 dimensional (3D) reconstruction of the clipped excision cavity, catheters and skin points. A computerised conformal semi-3D dose planning was used in all cases. For the last 15 implantations a CT-based 3D planning system was applied. 2. Based on the interim results of our pilot study further 71 patients were randomized to receive 50 Gy whole breast radiotherapy (Arm A: 36) or tumor bed irradiation alone (Arm B:35). In Arm B 28 of 35 women received 7 x 5.2 Gy sole BT. The other 7 patients were treated with wide local electron field. Overall 73 patients were treated with sole HDR-BT. Results: 1. Pilot study: at a median follow-up of 36 (25-52) months 2/45 (4.4%) local, 1/45 (2.2%) regional and 1/45 (2.2%) distant failures were observed. Both local relapses were salvaged successfully with re-excision and 50 Gy whole breast radiotherapy. 2. Randomized study: at a median follow-up of 16 (8-24) months neither local nor regional recurrence was observed. Distant metastasis was detected at 1 of 71 (1.4 %) randomized patients. For the entire 73 patients, treated with sole HDR-BT, the local control rate was 97.3% (71/73) at a median follow-up of 26 (8-52) months. The cosmetic results were judged to be excellent in each case. Fat necrosis developed in 1/73 (1.4%) patients. G2 fibrosis and G2 skin side effect was detected in 6/73 (8.2%) and 2/73 (2.7%) cases, respectively. Whole breast teletherapy is approximately two times more expensive, than HDRBT alone. The best conformity can be achieved with CT-image based 3D planning. Conclusions: sole HDR-BT with careful patient selection and adequate quality assurance seems to be a feasible and cost effective alternative to whole breast radiotherapy. Evidence based results and longer follow-up are required to define which subgroups of patients should be candidates for BT alone after BCS. Sole BT shortens the time of radiotherapy from 5-6 weeks to 5 days. The skin and volume sparing effect of interstitial irradiation might decrease the side effects of radiotherapy. Conformal 3D BT calls for new treatment planning terms and concepts.

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