- Email: [email protected]
Description of radiation induced liver disease using the lyman and local damage-organ injury NTCP models
Proceedings of the 43rd Annual ASTRO Meeting
performed to create a dose kernel for the 90Y voxel source. A convolution-based algorithm was implemented which convolves the radioactivity distribution from SPECT images with the voxel dose kernel to obtain the 3-D dose distribution. Patients’ CT scans and SPECT images were fused and the calculated dose distributions were superimposed on the CT scans for display and analysis. In addition, dose-volume histograms were generated that can be used to evaluate specific patients’ dose-responses. Results: We calculated 3-D dose distributions for a selected number of patients treated with 90Y microspheres. In contrast to the predictions of the partitional model, the uptake of radioactivity within the liver was found to be highly non-uniform. The ratio of tumor to non-tumor uptake can reach 10 fold. The calculated dose-volume histogram for a patient treated to a nominal whole liver dose of 150 Gy indicated that only 26% of the liver received a dose higher than 50 Gy while gross tumor received more than 150 Gy. At the same time, 15% of the liver received higher than 100 Gy and 27% of the gross tumor received more than 250 Gy. Conclusion: The 3-D dose calculation method provides complete account of dose to the liver and tumor(s). The isodose distribution superimposed on CT scans serves as a valuable tool to evaluate treatment efficacy. The calculated dose-volume histogram allows us to better evaluate patients’ dose-response and improve future clinical trials. We aim to extend this study to all patients treated with this procedure.
53
Radiation-Induced Liver Disease after Three-Dimensional Conformal Radiotherapy in Patients with Hepatocellular Carcinoma: Dosimetric Analysis and Implication
J.C. Cheng1,2, J. Wu3, C. Huang1, D. Huang3, S.H. Cheng1, J.J. Jian1 1 Department of Radiation Oncology, Koo Foundation Sun Yat-Sen Cancer Center, Taipei, Taiwan, 2Faculty of Medicine, National Yang-Ming University School of Medicine, Taipei, Taiwan, 3Department of Medical Physics, Koo Foundation Sun Yat-Sen Cancer Center, Taipei, Taiwan Purpose: This study is to use the dose-volume analysis to predict radiation-induced liver disease (RILD) for patients with hepatocellular carcinoma (HCC) and a large proportion of chronic hepatitis treated with three-dimensional conformal radiotherapy (3DCRT). Materials and Methods: From November 1993 through December 1999, 93 patients with intra-hepatic malignancies were treated with 3DCRT at our institution. Sixty-eight patients who were diagnosed with HCC and had complete three-dimensional dose-volume data were included in this study. The reasons for patient exclusion were follow-up interval less than 3 months after radiotherapy, incomplete dose-volume data in the palliative treatment, or the diagnosis other than HCC. Fifty of the 68 patients had chronic hepatitis before treatment, either type B or type C. According to Child-Pugh classification for cirrhosis of liver, 53 patients were in class A and 15 in class B. Forty-six patients underwent transcatheter arterial chemoembolization at least a month before 3DCRT to allow adequate recovery of hepatic function. RILD was defined as either anicteric elevation of alkaline phosphatase level of at least twofold and non-malignant ascites (classic RILD), or elevated transaminases of at lease fivefold the upper limit of normal or of pre-treatment level (Grade 3 or 4 hepatic toxicity of Common Toxicity Criteria Version 2.0 by National Cancer Institute)(non-classic RILD). No patient had whole liver irradiation. All patients were evaluated for RILD by physical examination, blood chemistries, and computed tomography of the abdomen, within 4 months from completion of radiotherapy. Three-dimensional treatment planning using dose-volume histogram analysis of the normal liver was used to compare the dosimetric difference between patients with and without RILD. Results: Twelve of the 68 patients developed RILD after 3DCRT, including 2 with classic type and 10 with non-classic type. Mean prescribed dose was 50.2 ⫾ 5.9Gy, in a daily fraction of 1.8-2Gy. None of the patient-related variables were associated with RILD. There was no difference in tumor volume (780ml vs. 737ml, p⫽0.86), normal liver volume (1210ml vs. 1153ml, p⫽0.64), V30Gy (percent volume of normal liver with radiation dose ⬎30Gy)(42% vs. 33%, p⫽0.05), and V50% (percent volume of normal liver with ⬎50% of the isocenter dose)(45% vs. 36%, p⫽0.06), between patients with and without RILD. Mean hepatic dose was significantly higher in patients with RILD (2504cGy vs. 1965cGy, p⫽0.02). Patients receiving radiation dose more than 28Gy had a significantly higher rate of RILD (4/5 vs. 8/51, p⫽0.02). The probability of produced RILD in patients could be expressed as: probability⫽1/ [1⫹exp-(0.12*mean dose-4.29)], with coefficients differed from 0 at the level of p⫽ 0.0018 and 0.027 , respectively. With the normal tissue complication probability (NTCP) model using volume effect parameter (n) of 0.32, curve steepness parameter (m) of 0.15, and TD50(1) of 40Gy, patients with RILD had significantly higher NTCP than those with no RILD (36.6% vs. 19.1%, p⫽0.005). With an attempt to estimate a new “n” by grouping patients and using a quartile plot, the best agreement between the calculated and observed complication probability was obtained with the value of 0.28. Conclusion: Dose volume histogram analysis can be effectively used to quantify the tolerance of liver to radiation. Patients with RILD had significantly higher mean hepatic dose and NTCP. The hepatic tolerance, expressed as either mean hepatic dose or the parameterization of NTCP model, was much lower in our patients with HCC and a high prevalence of chronic hepatitis, as compared to the other series. Further efforts should be made to test the modified model in an independent clinical trial.
54
Description of Radiation Induced Liver Disease using the Lyman and Local Damage-Organ Injury NTCP Models
L.A. Dawson, J.M. Balter, C.J. McGinn, T.S. Lawrence, R.K. Ten Haken Radiation Oncology, University of Michigan, Ann Arbor, MI Purpose: To better describe the dose-volume tolerance for radiation induced liver disease (RILD) using the Lyman-KutcherBurman (LKB) and a local damage - organ injury (D-I) normal tissue complication probability (NTCP) model. Materials and Methods: One-hundred-and-eighty-three patients treated with conformal radiation therapy (RT) for primary or secondary intrahepatic malignancies using 1.5 Gy - 1.65 Gy bid and concurrent hepatic arterial chemotherapy were prospectively followed for RILD. All patients had prothrombin times less then 1.3 x normal or were correctable with vitamin K (suggesting relatively normal liver function). Physical dose values in the 3D dose distributions for each patient were converted to normalized effective doses at 1.5 Gy per fraction using the linear quadratic model prior to DVH computation. Normal liver
33
34
I. J. Radiation Oncology
● Biology ● Physics
Volume 51, Number 3, Supplement 1, 2001
dose-volume histograms and RILD status for these patients were used as input data for determination of LKB and D-I model parameters. A complication (yes or no) was defined as RTOG grade 3 or 4 clinical RILD up to 4 months following completion of radiotherapy. Using data from all patients, a maximum likelihood analysis yielded best estimates for LKB and D-I model parameters for the liver. A multivariate analysis of potential factors associated with RILD (including age, sex, use of whole liver radiation, type of hepatic arterial chemotherapy (fluorodeoxyuridine (FUdR) or bromodeoxyuridine (BUdR)), type of liver tumor (primary hepatobiliary cancer versus liver metastases), mean dose and NTCP) was also completed. Refined LKB model parameters were then obtained for patient subgroups with different risks of RILD. Confidence intervals were determined by exploring the space around the maximum likely parameter set using profile-likelihood methods. Results: Nineteen of 183 patients treated with focal liver radiation developed grade 3 or 4 RILD. The LKB and the D-I models were fit to the complication data for the entire group as follows: TD50(1), “m” and “n” LKB model parameters and 95% confidence intervals were 42.0 Gy (40 Gy, 51 Gy), 0.16 (0.10, 0.3) and 0.94 ( 0.67, ⬎2) respectively. The ’n’ parameter is larger than previously described, suggesting a strong volume effect for RILD and a correlation of RILD with mean liver dose. No cases of RILD were observed when the mean liver dose was less than 31 Gy. The D-I model parameters and 68% confidence intervals were: D50 ⫽ 43 Gy (36 Gy, 90 Gy); k ⫽ 2.7 (1.8, 7); F50 ⫽ 0.50 (0.37, 0.78); and ⫽ 0.1 (0.05, 0.21). Multivariate analysis demonstrated that in addition to mean dose and NTCP, primary hepatobiliary cancer diagnosis (versus liver metastases), BUdR hepatic arterial chemotherapy (versus FUdR) and male sex were significantly associated with RILD. Refined LKB model parameters were obtained for patient subgroups with different risks of RILD. For patients with primary liver cancer treated with FUdR, LKB model parameters were: TD50(1)⫽ 39 Gy, “m”⫽ 0.07, and “n”⫽ 0.78, whereas for patients with liver metastases treated with FUdR, the parameters were as follows: TD50(1)⫽ 50 Gy, “m”⫽ 0.17, and “n”⫽ 1.0. Conclusion: These data demonstrate that the liver exhibits a larger volume effect and a lower volume threshold for RILD then previously predicted, suggesting that mean liver dose may be useful in ranking focal liver RT plans. Our data suggests that the tolerance of the liver to radiation is lowest in patients with primary hepatobiliary cancer treated with hepatic arterial BUdR, and highest in patients with liver metastases treated with hepatic arterial FUdR. This work was supported in part by National Cancer Institute grant P01 CA59827, R01 CA85684 and M01 RR00042
55
Preliminary Analysis of RTOG 9708: Adjuvant Postoperative Irradiation Combined with Cisplatin/Taxol Chemotherapy following Surgery for Patients with High-Risk Endometrial Cancer
K. Greven1, K. Winter2, K. Underhill3, C. Moorthy4, J. Cooper5, T. Burke6 1 Radiation Oncology, Wake Forest University School of Medicine, Winston Salem, NC, 2Statistician, Radiation Therapy Oncology Group, Philadelphia, PA, 3Radiation Oncology, Thomas Jefferson University Hospital, Philadelphia, PA, 4 Radiation Oncology, New York Medical College, Valhalla, NY, 5Radiation Oncology, New York University Medical Center, New York, NY, 6Gynecologic Oncology, UT MD Anderson Cancer Center, Houston, TX Purpose: Patients with completely resected high-risk endometrial cancer are at risk of disease recurrence even with the addition of adjuvant pelvic radiation. A phase II study was completed by the RTOG to assess the safety and toxicity of chemotherapy when combined with radiation for these patients. Materials and Methods: Eligibility requirements included those patients who had a total abdominal hysterectomy and bilateral salpingo-oophorectomy with grade 2 or 3 endometrial adenocarcinoma with either ⬎50% myometrial invasion, stromal invasion of cervix, or pelvic-confined extrauterine disease. This study was designed to administer 4500cGy in 25 fractions to the pelvis along with cisplatin (50mg/M2) on days 1 and 28. Vaginal brachytherapy with low dose rate (1 x 20Gy to surface) or high dose rate (3 x 6 Gy to the surface) applicator was performed after the external beam radiation. Four courses of cisplatin (50mg/M2) and Taxol (175mg/M2) were given at 4 week intervals following completion of radiotherapy. Results: Forty-six patients were entered between 10/97 and 4/99. Two patients were considered ineligible (one with a previous bladder cancer and one with surgery more than 8 weeks prior to start of RT). Follow-up times range from 4.8 months to 31.5 months with a median of 17.8 months. Stage of disease was III, II, and I in 61%, 16%, and 23% of patients, respectively. Ten patients were not evaluable for protocol completion due to incomplete treatment data. The protocol completion rate was 33 out of 34 evaluable patients. Acute toxicities during RT/CDDP were grade 1 in 63%, grade 2 in 77%, grade 3 in 33% and grade 4 in 2%. During the adjuvant chemotherapy, toxicity was grade 1 in 7%, grade 2 in 7%, grade 3 in 21%, and grade 4 in 62%. Severe toxicity was primarily hematologic. Chronic toxicity was grade 1 in 23%, grade 2 in 35%, grade 3 in 14%, and grade 4 in 2% which included one patient with a grade 4 small bowel complication. At 12 months locoregional recurrence, distant recurrence and overall survival are 2%, 5% and 95% respectively. Conclusion: This treatment protocol demonstrates an excellent treatment completion rate and acceptable toxicity. Longer follow-up is needed to assess outcome. In order to assess efficacy of this adjuvant treatment program a phase III trial (RTOG 9905) has been activated and is currently accruing patients with high-risk uterine-confined disease to be randomized between radiation alone or radiation with chemotherapy.
56
Ten Year Outcome Including Patterns of Failure for Adjuvant Whole Abdominopelvic Irradiation in High Risk and Poor Histology Patients with Endometrial Carcinoma
K.D. Stewart1, S. Weiner2, P. Chen1, C. Mitchell1, D.A. Brabbins1, J. Jennings2, J.S. Stromberg1, A.A. Martinez1 1 Radiation Oncology, William Beaumont Hospital, Royal Oak, MI, 2Gynecologic Oncology, William Beaumont Hospital, Royal Oak, MI Purpose: Evaluate the long term results of treatment utilizing adjuvant whole abdominal irradiation with a pelvic/vaginal boost (WAPI) in patients with stage I - III endometrial carcinoma at high risk for intra-abdominopelvic recurrence including clear cell and serous-papillary histologies.
performed to create a dose kernel for the 90Y voxel source. A convolution-based algorithm was implemented which convolves the radioactivity distribution from SPECT images with the voxel dose kernel to obtain the 3-D dose distribution. Patients’ CT scans and SPECT images were fused and the calculated dose distributions were superimposed on the CT scans for display and analysis. In addition, dose-volume histograms were generated that can be used to evaluate specific patients’ dose-responses. Results: We calculated 3-D dose distributions for a selected number of patients treated with 90Y microspheres. In contrast to the predictions of the partitional model, the uptake of radioactivity within the liver was found to be highly non-uniform. The ratio of tumor to non-tumor uptake can reach 10 fold. The calculated dose-volume histogram for a patient treated to a nominal whole liver dose of 150 Gy indicated that only 26% of the liver received a dose higher than 50 Gy while gross tumor received more than 150 Gy. At the same time, 15% of the liver received higher than 100 Gy and 27% of the gross tumor received more than 250 Gy. Conclusion: The 3-D dose calculation method provides complete account of dose to the liver and tumor(s). The isodose distribution superimposed on CT scans serves as a valuable tool to evaluate treatment efficacy. The calculated dose-volume histogram allows us to better evaluate patients’ dose-response and improve future clinical trials. We aim to extend this study to all patients treated with this procedure.
53
Radiation-Induced Liver Disease after Three-Dimensional Conformal Radiotherapy in Patients with Hepatocellular Carcinoma: Dosimetric Analysis and Implication
J.C. Cheng1,2, J. Wu3, C. Huang1, D. Huang3, S.H. Cheng1, J.J. Jian1 1 Department of Radiation Oncology, Koo Foundation Sun Yat-Sen Cancer Center, Taipei, Taiwan, 2Faculty of Medicine, National Yang-Ming University School of Medicine, Taipei, Taiwan, 3Department of Medical Physics, Koo Foundation Sun Yat-Sen Cancer Center, Taipei, Taiwan Purpose: This study is to use the dose-volume analysis to predict radiation-induced liver disease (RILD) for patients with hepatocellular carcinoma (HCC) and a large proportion of chronic hepatitis treated with three-dimensional conformal radiotherapy (3DCRT). Materials and Methods: From November 1993 through December 1999, 93 patients with intra-hepatic malignancies were treated with 3DCRT at our institution. Sixty-eight patients who were diagnosed with HCC and had complete three-dimensional dose-volume data were included in this study. The reasons for patient exclusion were follow-up interval less than 3 months after radiotherapy, incomplete dose-volume data in the palliative treatment, or the diagnosis other than HCC. Fifty of the 68 patients had chronic hepatitis before treatment, either type B or type C. According to Child-Pugh classification for cirrhosis of liver, 53 patients were in class A and 15 in class B. Forty-six patients underwent transcatheter arterial chemoembolization at least a month before 3DCRT to allow adequate recovery of hepatic function. RILD was defined as either anicteric elevation of alkaline phosphatase level of at least twofold and non-malignant ascites (classic RILD), or elevated transaminases of at lease fivefold the upper limit of normal or of pre-treatment level (Grade 3 or 4 hepatic toxicity of Common Toxicity Criteria Version 2.0 by National Cancer Institute)(non-classic RILD). No patient had whole liver irradiation. All patients were evaluated for RILD by physical examination, blood chemistries, and computed tomography of the abdomen, within 4 months from completion of radiotherapy. Three-dimensional treatment planning using dose-volume histogram analysis of the normal liver was used to compare the dosimetric difference between patients with and without RILD. Results: Twelve of the 68 patients developed RILD after 3DCRT, including 2 with classic type and 10 with non-classic type. Mean prescribed dose was 50.2 ⫾ 5.9Gy, in a daily fraction of 1.8-2Gy. None of the patient-related variables were associated with RILD. There was no difference in tumor volume (780ml vs. 737ml, p⫽0.86), normal liver volume (1210ml vs. 1153ml, p⫽0.64), V30Gy (percent volume of normal liver with radiation dose ⬎30Gy)(42% vs. 33%, p⫽0.05), and V50% (percent volume of normal liver with ⬎50% of the isocenter dose)(45% vs. 36%, p⫽0.06), between patients with and without RILD. Mean hepatic dose was significantly higher in patients with RILD (2504cGy vs. 1965cGy, p⫽0.02). Patients receiving radiation dose more than 28Gy had a significantly higher rate of RILD (4/5 vs. 8/51, p⫽0.02). The probability of produced RILD in patients could be expressed as: probability⫽1/ [1⫹exp-(0.12*mean dose-4.29)], with coefficients differed from 0 at the level of p⫽ 0.0018 and 0.027 , respectively. With the normal tissue complication probability (NTCP) model using volume effect parameter (n) of 0.32, curve steepness parameter (m) of 0.15, and TD50(1) of 40Gy, patients with RILD had significantly higher NTCP than those with no RILD (36.6% vs. 19.1%, p⫽0.005). With an attempt to estimate a new “n” by grouping patients and using a quartile plot, the best agreement between the calculated and observed complication probability was obtained with the value of 0.28. Conclusion: Dose volume histogram analysis can be effectively used to quantify the tolerance of liver to radiation. Patients with RILD had significantly higher mean hepatic dose and NTCP. The hepatic tolerance, expressed as either mean hepatic dose or the parameterization of NTCP model, was much lower in our patients with HCC and a high prevalence of chronic hepatitis, as compared to the other series. Further efforts should be made to test the modified model in an independent clinical trial.
54
Description of Radiation Induced Liver Disease using the Lyman and Local Damage-Organ Injury NTCP Models
L.A. Dawson, J.M. Balter, C.J. McGinn, T.S. Lawrence, R.K. Ten Haken Radiation Oncology, University of Michigan, Ann Arbor, MI Purpose: To better describe the dose-volume tolerance for radiation induced liver disease (RILD) using the Lyman-KutcherBurman (LKB) and a local damage - organ injury (D-I) normal tissue complication probability (NTCP) model. Materials and Methods: One-hundred-and-eighty-three patients treated with conformal radiation therapy (RT) for primary or secondary intrahepatic malignancies using 1.5 Gy - 1.65 Gy bid and concurrent hepatic arterial chemotherapy were prospectively followed for RILD. All patients had prothrombin times less then 1.3 x normal or were correctable with vitamin K (suggesting relatively normal liver function). Physical dose values in the 3D dose distributions for each patient were converted to normalized effective doses at 1.5 Gy per fraction using the linear quadratic model prior to DVH computation. Normal liver
33
34
I. J. Radiation Oncology
● Biology ● Physics
Volume 51, Number 3, Supplement 1, 2001
dose-volume histograms and RILD status for these patients were used as input data for determination of LKB and D-I model parameters. A complication (yes or no) was defined as RTOG grade 3 or 4 clinical RILD up to 4 months following completion of radiotherapy. Using data from all patients, a maximum likelihood analysis yielded best estimates for LKB and D-I model parameters for the liver. A multivariate analysis of potential factors associated with RILD (including age, sex, use of whole liver radiation, type of hepatic arterial chemotherapy (fluorodeoxyuridine (FUdR) or bromodeoxyuridine (BUdR)), type of liver tumor (primary hepatobiliary cancer versus liver metastases), mean dose and NTCP) was also completed. Refined LKB model parameters were then obtained for patient subgroups with different risks of RILD. Confidence intervals were determined by exploring the space around the maximum likely parameter set using profile-likelihood methods. Results: Nineteen of 183 patients treated with focal liver radiation developed grade 3 or 4 RILD. The LKB and the D-I models were fit to the complication data for the entire group as follows: TD50(1), “m” and “n” LKB model parameters and 95% confidence intervals were 42.0 Gy (40 Gy, 51 Gy), 0.16 (0.10, 0.3) and 0.94 ( 0.67, ⬎2) respectively. The ’n’ parameter is larger than previously described, suggesting a strong volume effect for RILD and a correlation of RILD with mean liver dose. No cases of RILD were observed when the mean liver dose was less than 31 Gy. The D-I model parameters and 68% confidence intervals were: D50 ⫽ 43 Gy (36 Gy, 90 Gy); k ⫽ 2.7 (1.8, 7); F50 ⫽ 0.50 (0.37, 0.78); and ⫽ 0.1 (0.05, 0.21). Multivariate analysis demonstrated that in addition to mean dose and NTCP, primary hepatobiliary cancer diagnosis (versus liver metastases), BUdR hepatic arterial chemotherapy (versus FUdR) and male sex were significantly associated with RILD. Refined LKB model parameters were obtained for patient subgroups with different risks of RILD. For patients with primary liver cancer treated with FUdR, LKB model parameters were: TD50(1)⫽ 39 Gy, “m”⫽ 0.07, and “n”⫽ 0.78, whereas for patients with liver metastases treated with FUdR, the parameters were as follows: TD50(1)⫽ 50 Gy, “m”⫽ 0.17, and “n”⫽ 1.0. Conclusion: These data demonstrate that the liver exhibits a larger volume effect and a lower volume threshold for RILD then previously predicted, suggesting that mean liver dose may be useful in ranking focal liver RT plans. Our data suggests that the tolerance of the liver to radiation is lowest in patients with primary hepatobiliary cancer treated with hepatic arterial BUdR, and highest in patients with liver metastases treated with hepatic arterial FUdR. This work was supported in part by National Cancer Institute grant P01 CA59827, R01 CA85684 and M01 RR00042
55
Preliminary Analysis of RTOG 9708: Adjuvant Postoperative Irradiation Combined with Cisplatin/Taxol Chemotherapy following Surgery for Patients with High-Risk Endometrial Cancer
K. Greven1, K. Winter2, K. Underhill3, C. Moorthy4, J. Cooper5, T. Burke6 1 Radiation Oncology, Wake Forest University School of Medicine, Winston Salem, NC, 2Statistician, Radiation Therapy Oncology Group, Philadelphia, PA, 3Radiation Oncology, Thomas Jefferson University Hospital, Philadelphia, PA, 4 Radiation Oncology, New York Medical College, Valhalla, NY, 5Radiation Oncology, New York University Medical Center, New York, NY, 6Gynecologic Oncology, UT MD Anderson Cancer Center, Houston, TX Purpose: Patients with completely resected high-risk endometrial cancer are at risk of disease recurrence even with the addition of adjuvant pelvic radiation. A phase II study was completed by the RTOG to assess the safety and toxicity of chemotherapy when combined with radiation for these patients. Materials and Methods: Eligibility requirements included those patients who had a total abdominal hysterectomy and bilateral salpingo-oophorectomy with grade 2 or 3 endometrial adenocarcinoma with either ⬎50% myometrial invasion, stromal invasion of cervix, or pelvic-confined extrauterine disease. This study was designed to administer 4500cGy in 25 fractions to the pelvis along with cisplatin (50mg/M2) on days 1 and 28. Vaginal brachytherapy with low dose rate (1 x 20Gy to surface) or high dose rate (3 x 6 Gy to the surface) applicator was performed after the external beam radiation. Four courses of cisplatin (50mg/M2) and Taxol (175mg/M2) were given at 4 week intervals following completion of radiotherapy. Results: Forty-six patients were entered between 10/97 and 4/99. Two patients were considered ineligible (one with a previous bladder cancer and one with surgery more than 8 weeks prior to start of RT). Follow-up times range from 4.8 months to 31.5 months with a median of 17.8 months. Stage of disease was III, II, and I in 61%, 16%, and 23% of patients, respectively. Ten patients were not evaluable for protocol completion due to incomplete treatment data. The protocol completion rate was 33 out of 34 evaluable patients. Acute toxicities during RT/CDDP were grade 1 in 63%, grade 2 in 77%, grade 3 in 33% and grade 4 in 2%. During the adjuvant chemotherapy, toxicity was grade 1 in 7%, grade 2 in 7%, grade 3 in 21%, and grade 4 in 62%. Severe toxicity was primarily hematologic. Chronic toxicity was grade 1 in 23%, grade 2 in 35%, grade 3 in 14%, and grade 4 in 2% which included one patient with a grade 4 small bowel complication. At 12 months locoregional recurrence, distant recurrence and overall survival are 2%, 5% and 95% respectively. Conclusion: This treatment protocol demonstrates an excellent treatment completion rate and acceptable toxicity. Longer follow-up is needed to assess outcome. In order to assess efficacy of this adjuvant treatment program a phase III trial (RTOG 9905) has been activated and is currently accruing patients with high-risk uterine-confined disease to be randomized between radiation alone or radiation with chemotherapy.
56
Ten Year Outcome Including Patterns of Failure for Adjuvant Whole Abdominopelvic Irradiation in High Risk and Poor Histology Patients with Endometrial Carcinoma
K.D. Stewart1, S. Weiner2, P. Chen1, C. Mitchell1, D.A. Brabbins1, J. Jennings2, J.S. Stromberg1, A.A. Martinez1 1 Radiation Oncology, William Beaumont Hospital, Royal Oak, MI, 2Gynecologic Oncology, William Beaumont Hospital, Royal Oak, MI Purpose: Evaluate the long term results of treatment utilizing adjuvant whole abdominal irradiation with a pelvic/vaginal boost (WAPI) in patients with stage I - III endometrial carcinoma at high risk for intra-abdominopelvic recurrence including clear cell and serous-papillary histologies.