- Email: [email protected]
20 The Duration of LHRH Treatment in Men Receiving Radical Radiotherapy for Prostate Cancer
$6
September 7-10
prostate dosimetry (Vl00, V150 and Dg0), and rectal DVH for VR150%, VR100% and VR50% (volume of the rectum receiving 150, 100 and 50% of the prescribed dose in cc). Acute toxicity was scored on 6 weeks and late toxicity on >6 month follow up using RTOG scale. Results: 21% pts developed acute rectal toxicity: 15% gr 1 and 6 % gr 2. 30% developed late rectal toxicity: 20% gr 1, 9.4% gr 2 and 0.4% gr 3. On MVA, factors predictive for late gr >2 rectal toxicity include: iPSA (p=0.03) and D90 (p=0.033). For D90 <125 Gy, 125-150 Gy, 150-175 Gy and >175 Gy corresponding late grade >2 toxicity is 9%, 6.8%, 10% and 15.5% respectively. If VR100=0 cc: gr >1 and gr >2 late rectal toxicity were 5% vs 0%. If VR100=I cc: gr >1 and gr >2 toxicity were 26% vs 7%. For VR100=2cc: gr >1 and gr >2 toxicity were 3 5% vs 9.5 % respectively. Acute toxicity was predictive of late gr 2 toxicity (6%, 19% and 27% for gr 0, gr 1 and gr 2 acute proctitis respectively; p=<0.01). Acute urinary obstruction was predictor for late gr 2 toxicity (p=0.01), Conclusions: Anterior 1/2 rectum DVH (VR100), D90, AUR, predict late >1 late rectal toxicity. D90 and acute rectal toxicity predict for >2 late rectal toxicity. 18 Predictive Factors for Erectile Dysfunction in Men w i t h P r o s t a t e Cancer Following Prostate B r a c h y t h e r a p y : I s Dose to the Penile Bulb I m p o r t a n t ?
M. Keyes ~, G. MacDonald ~, A. Kruk 2, G. Duncan ~, V. Moravan 3, W.J. Morris 1 Department of Radiation Oncology, Vancouver Cancer Centre, British Columbia Cancer Agency Vancouver, British ColumbiaZ; Department of Radiation Therapy, Vancouver Cancer Centre, British Columbia Cancer Agency, Vancouver, British Columbia2; Population and Preventive Oncology, British Columbia Cancer Agency, Vancouver, British Columbia 3 Purpose: To determine predictive factors for post-implant erectile dysfunction (ED), specifically to assess the impact of penile bulb dose. M a t e r i a l and Methods: 342 consecutive patients potent preimplant with at least 2 years follow-up were included in the study. Patient, tumor, treatment and dosimetric data were prospectively collected. The penile bulb was contoured by 2 investigators and D95 and D50 calculated. Post-implant ED was defined by both physicia n-documented. Binary logistic regression analysis was used to create multivariable models of predictors for ED at 1, 2 and 3 years post-implant. Results: Potency preservation rate at 3 year follow up for different age groups include: age <60 = 73%, age 60-69 = 62% and age >70 = 46%. Multivariable analyses revealed age and degree of pre-implant erectile function to be consistent and most significant predictors of ED (p=0.0001) (year 1, 2 and 3 of follow-up). Use of androgen suppression (AS) was significant at the 1 year (p=0.0001), but not thereafter, in keeping with testosterone recovery. Other predictive MVA factors include: implant order (p=0.001), PUTV (p=0.04) and number of needles (p=0.002). These may ultimately point to trauma to the bulb as an important predictive factor of ED. Hypertension (p=0.02), and smoking (0.01) were also predictive. Penile bulb dosimetry was found to predict ED. Recovery of potency (30% of pts. per year) was seen regardless of whether patients had received prior AS or used potency aids. Conclusion: The strongest factors predictive for ED after prostate brachytherapy include age, pretreatment ED and history of AS. Significance of implant order, larger PUTV and number of needles used for implant is suggestive of trauma as a possible cause of ED after prostate Brachytherapy. Dose to the bulb is unrelated to development of ED. Potency recovery (regardless of use of AS and potency aids) is not uncommon.
CARO 2005
19 Sexual Desire C o r r e l a t e s w i t h P r e f e r e n c e s for Short versus Long Term Androgen Deprivation and R a d i o t h e r a p y in P r o s t a t e Cancer Survivors
D. Wilke 1, M. Krahn 2, P, Warde 3, A. Bezjak 3, G. Tomlinson 2, R. Rutledge 1, A. Detsky 4 Nova Scotia Cancer Centre, Dalhousie University, Halifax, Nova Scotia1; University Health Network, University of Toronto, Toronto, Ontario2; Princess Margaret Hospital, University of Toronto, Toronto, Ontario3; Mount Sinai Hospital, University of Toronto, Toronto, Ontario 4 Background: Given a hypothetical scenario, patients may be willing to trade-off survival in order to be spared the side effects of long-term versus short-term androgen deprivation (AD) and radiotherapy for the treatment of Locally Advanced Prostate Cancer. Methods: Sixty-seven prostate cancer survivors who were treated with radiotherapy participated in a structured interview. Current sexual function was assessed using the International Index of Erectile Function (IIEF) and their current prostate cancer-specific health state was assessed using the prostate cancer health state classification system of the Patient Oriented Prostate Utility Scale (PORPUS). Preferences for long versus short-term AD and radiotherapy were elicited using the Probability trade-off (PTO) technique. Results: Given a hypothetical scenario, prostate cancer survivors were willing, on average, to trade off 8.3% [95% C.I.: 7.1 - 9,3%] absolute prostate cancer- specific survival (PCSS) to avoid long-term versus short-term AD. As per RTOG 9202, long versus short-term AD and radiotherapy provides only a 3.4% benefit in PCSS at 5 years. When given the scenario of no improvement in overall survival, patients were still willing to trade survival, but required, on average, an additional 1.5% gain in PCSS (p<0.0001). Willingness to trade survival, using the PTO technique, was correlated with current sexual desire, as measured by the sexual desire domain score of the IIEF (Spearman Rank r=0.5, p<0.0001). Sexual desire domain score remained significant on multivariable analysis of factors related to willingness to trade survival. Conclusion: Prostate cancer survivors are, in theory, willing to trade survival in order to be spared the side effects of long versus short-term androgen deprivation. Sexual desire is correlated with willingness to trade PCSS. 2O The D u r a t i o n of LHRH T r e a t m e n t in Men Radical R a d i o t h e r a p y for P r o s t a t e Cancer
Receiving
P. Blood 1, C. Paul2, ]. Barnett 3, ]. Spinelli~, T. Pickles ~, G. Steinhoff ~ British Columbia Cancer Agency, University of British Columbia, Victoria, British Columbia1; University of British Columbia, Vancouver, British Columbia2; British Columbia Cancer Agency, Victoria, British Columbia3; Gary Steinhoff Clinical Research, Victoria, British Columbia 4 Rationale: Since 1997, randomized trials have shown improved outcomes when LHRH treatment is added to radical radiotherapy for selected patients with prostate cancer. However, there is a wide variation in the duration of LHRH treatment in these studies, from 4 months to 3 years. Little information is available on the extent to which men with prostate cancer are being treated with LHRH injections in this setting. Objectives: To measure the extent to which men receiving radical radiation treatment for prostate cancer are receiving LHRH treatment; by determining the proportion of men receiving LHRH prescriptions and the duration of LHRH prescriptions associated with radical radiation treatment. Methods: A cohort of men diagnosed with prostate cancer between 1986 and 2000 was assembled from the Provincial Cancer Registry. The start date of radiation treatment was
CARO 2005
September 7-10
identified for those men who received radical radiation treatment. LHRH prescriptions dispensed between one year before and three years after the start date of radical radiation treatment were identified from the pharmacy records in the Cancer Registry. Results: 34,521 men were diagnosed with prostate cancer between 1986 and 2000 and 11,787 of these men received radical radiation treatment. 3,098 of the men who received radical radiation treatment also received LHRH injections. The mean duration of LHRH injections for men treated with radical radiation in 2000 was 15 months (standard deviation 10 months) and the median was 12 months. The proportion of men dispensed LHRH injections in association with radical radiation treatment increased from less than 9% in 1995 to 71% in 2000. Conclusions: LHRH treatment is administered to the majority of men who currently receive radical radiation treatment for prostate cancer. There is a wide variation in the duration of LHRH treatment, which reflects the uncertainty in the evidence available on the optimal duration of adjuvant LHRH treatment. 21 Testosterone and Erectile Function Recovery After Radiotherapy and Long - Term Androgen Deprivation With LHRH Analogues D. Wilke I, C. Parker e, A. Andronowski I, D. Tsuji3, C. Carton 3, M. Gospodarowicz 3, P. Warde 3 Nova Scotia Cancer Centre, Dalhousie University, Halifax, Nova Scotia1; Royal Marsden Hospital, United Kingdom2; Princess Margaret Hospital, University of Toronto, Toronto, Ontario 3
Background: There is a paucity of data regarding the return of sexual function and recovery of testosterone in patients who have had radiotherapy and Iongterm adjuvant androgen deprivation. Methods: Patients at a major cancer center who had completed radiotherapy and Iongterm adjuvant androgen deprivation (3 years) with an LHRH agonist were approached to participate. Patients completed the International index of erectile function (IIEF) and had Serum levels of Testosterone (I-F), Luteinizing hormone (LH), Follicle stimulating hormone, Prostate specific antigen, and Hemoglobin measured. Assessments were repeated at one year. Results: Twenty patients were accrued from April 2000 to July 2001. Median age at entry into the study was 71 (range 55 to 81). Mean pretreatment serum TT was 10.6 nmol/L (range 0.3 to 16.6). At entry, the mean serum I F was 4.4 nmol/L (range 0.4 to 16), and at 1 year, increased to a mean value of 7.7 nmol/L (range 1.1 to 20.4) (p=0.0005). Prior to treatment, 11 out of 20 patients were potent. There was no significant improvement in any domain score of the IIEF over the one year time period. Median duration of castrate levels of-IF (<1.7 nmol/L) from cessation of androgen deprivation was 8 months. Using a cutoff of 8.0 nmol/L, the median duration of subnormal levels of I F was 2.3 years, and at 4.2 years 25% of patients had a persistently subnormal 1-1. Median duration of subnormal levels of LH was 3.8 months. Prognostic factors related to -I-I recovery were: Age and LH/-I-I ratio. Time to recovery of LH was sooner than TT (p<0.0001), suggesting the delay to recovery is at the level of the testicle. Two patients regained erectile function sufficient for intercourse. Conclusion: Testosterone levels improved over time, but remained subnormal years after cessation of treatment. Return of sexual function occurred in a minority of patients. 22 Development and Psychometric Properties of Prostate Cancer Radiation Toxicity Questionnaire
the
G. Rodrigues, M. Lock, D. O'Souza, ]. Radwan, R. Ash, V. Venkatsean, G. Bauman London Regional Cancer Program, University of Western Ontario, London, Ontario
$7
Introduction: The objective of this study was to construct a prostate cancer late radiation toxicity (PCRT) questionnaire with associated health-related quality of life (HRQoL) domains. Methods: An initial questionnaire was subjected to both patient (n=8) and expert (n=7) opinion. A pilot study (n=37) assessed patient feedback, ease of administration, and acceptance. Item reduction (n=100) based on response heterogeneity, factor analysis and Cronbach's alpha analysis was performed. Reliability testing (n=274) was performed using test-retest methodology and calculation of intraclass correlation coefficients (CC). Validity testing (n=274) consisted of discriminant and various construct validity tests 1. calculation of Pearson CC between the PCRT and different HRQoL instruments, and 2. comparison of mean brachytherapy versus external-beam radiation therapy domain scores by Student's t-test). Results: The pilot study demonstrated that the PCRT was comprehensive (94%) and easy to administer (1.3% missing data). Item reduction resulted in three HRQoL subscales: (4 item GU alpha = 0.639, 12 item GI = 0.859, 5 item sexual = 0.700). Test-retest reliability demonstrated intraclass correlation coefficients of 0.811 (GU), 0.842 (GI), and 0.740 (sexual). Discriminate validity analysis demonstrated Pearson CC of 0.449 (GU-GI), 0.200 (sexuaI-GU), and 0.09 (sexuaI-GI). Content validity analysis demonstrated significant correlations between analogous subscales between PCRT and the PCQoL (range 0.35-0.78). Smaller correlations exist between the PCRT and FACT-G (0.19-0.39) and SF-36 (0.03-0.34). Difference scores between brachytherapy and external-beam favoured brachytherapy [4.13 (GI, p=0.02), 3.50 (sexual, p=0.36), and 3.63 (GU, p=0.14)]. Conclusions: The HRQoL subscales generated from the PCRT have been shown to have good internal consistency with documented reliability and validity. 23 Patient-Reported Late Toxicity Following High-dose Radiation Therapy for Prostate Cancer: The Princess Margaret Hospital Experience
M. Skala, C. Catton, L. Divanbeigi, A. Bayley, R. Bristow, P. Catton, J. Crook, M. Gospodarowicz, M. McLean, M. Milosevic, G. Lockwood, T. Rosewall, P. Warde Princess Margaret Hospital, University of Toronto, Toronto, Ontario Objective: To determine the patient-reported incidence of late gastro-intestinal (GI) and genito-urinary (GU) toxicity following high-dose radiation therapy at the Princess Margaret Hospital (PMH). Methods: We sent a validated late toxicity postal questionnaire to 754 men with T1-T2 prostate cancer, who received 75.6 Gy or 79.8 Gy to the prostate gland using 3DCRT or IMRT between 1997 and 2003. All patients were treated with daily image guidance. Three fiducial markers were inserted into the prostate gland before treatment planning, to allow daily target verification. Patient reported toxicity was graded using the modified RTOG-LENT scoring system. Results: 416 (55%) men answered the questionnaire. At a median follow-up of 3.5 years, the incidence of RTOG Grade 0 late GI toxicity was 75%, Grade 1-23%, Grade 2-1.2% and Grade 3-1.0%. Four patients experienced Grade 3 GI toxicity. Two reported prolonged use of steroid per enema, one reported persistent use of incontinence pads, and one underwent numerous coagulation procedures. The incidence of RTOG Grade 0 late GU toxicity was 71%, Grade 1-23%, Grade 24.3% and Grade 3-1.0%. Four patients experienced Grade 3 GU toxicity. Three reported persistent use of incontinence pads, and one experienced nocturia more frequently than every hour. Patient-reported pre-treatment potency rate was 73%. Following treatment, 46% of previously potent men were able to achieve erections sufficient for intercourse at least 50% the time. 18% reported use of PDE-5 inhibitors, and 83% found these to be effective.
September 7-10
prostate dosimetry (Vl00, V150 and Dg0), and rectal DVH for VR150%, VR100% and VR50% (volume of the rectum receiving 150, 100 and 50% of the prescribed dose in cc). Acute toxicity was scored on 6 weeks and late toxicity on >6 month follow up using RTOG scale. Results: 21% pts developed acute rectal toxicity: 15% gr 1 and 6 % gr 2. 30% developed late rectal toxicity: 20% gr 1, 9.4% gr 2 and 0.4% gr 3. On MVA, factors predictive for late gr >2 rectal toxicity include: iPSA (p=0.03) and D90 (p=0.033). For D90 <125 Gy, 125-150 Gy, 150-175 Gy and >175 Gy corresponding late grade >2 toxicity is 9%, 6.8%, 10% and 15.5% respectively. If VR100=0 cc: gr >1 and gr >2 late rectal toxicity were 5% vs 0%. If VR100=I cc: gr >1 and gr >2 toxicity were 26% vs 7%. For VR100=2cc: gr >1 and gr >2 toxicity were 3 5% vs 9.5 % respectively. Acute toxicity was predictive of late gr 2 toxicity (6%, 19% and 27% for gr 0, gr 1 and gr 2 acute proctitis respectively; p=<0.01). Acute urinary obstruction was predictor for late gr 2 toxicity (p=0.01), Conclusions: Anterior 1/2 rectum DVH (VR100), D90, AUR, predict late >1 late rectal toxicity. D90 and acute rectal toxicity predict for >2 late rectal toxicity. 18 Predictive Factors for Erectile Dysfunction in Men w i t h P r o s t a t e Cancer Following Prostate B r a c h y t h e r a p y : I s Dose to the Penile Bulb I m p o r t a n t ?
M. Keyes ~, G. MacDonald ~, A. Kruk 2, G. Duncan ~, V. Moravan 3, W.J. Morris 1 Department of Radiation Oncology, Vancouver Cancer Centre, British Columbia Cancer Agency Vancouver, British ColumbiaZ; Department of Radiation Therapy, Vancouver Cancer Centre, British Columbia Cancer Agency, Vancouver, British Columbia2; Population and Preventive Oncology, British Columbia Cancer Agency, Vancouver, British Columbia 3 Purpose: To determine predictive factors for post-implant erectile dysfunction (ED), specifically to assess the impact of penile bulb dose. M a t e r i a l and Methods: 342 consecutive patients potent preimplant with at least 2 years follow-up were included in the study. Patient, tumor, treatment and dosimetric data were prospectively collected. The penile bulb was contoured by 2 investigators and D95 and D50 calculated. Post-implant ED was defined by both physicia n-documented. Binary logistic regression analysis was used to create multivariable models of predictors for ED at 1, 2 and 3 years post-implant. Results: Potency preservation rate at 3 year follow up for different age groups include: age <60 = 73%, age 60-69 = 62% and age >70 = 46%. Multivariable analyses revealed age and degree of pre-implant erectile function to be consistent and most significant predictors of ED (p=0.0001) (year 1, 2 and 3 of follow-up). Use of androgen suppression (AS) was significant at the 1 year (p=0.0001), but not thereafter, in keeping with testosterone recovery. Other predictive MVA factors include: implant order (p=0.001), PUTV (p=0.04) and number of needles (p=0.002). These may ultimately point to trauma to the bulb as an important predictive factor of ED. Hypertension (p=0.02), and smoking (0.01) were also predictive. Penile bulb dosimetry was found to predict ED. Recovery of potency (30% of pts. per year) was seen regardless of whether patients had received prior AS or used potency aids. Conclusion: The strongest factors predictive for ED after prostate brachytherapy include age, pretreatment ED and history of AS. Significance of implant order, larger PUTV and number of needles used for implant is suggestive of trauma as a possible cause of ED after prostate Brachytherapy. Dose to the bulb is unrelated to development of ED. Potency recovery (regardless of use of AS and potency aids) is not uncommon.
CARO 2005
19 Sexual Desire C o r r e l a t e s w i t h P r e f e r e n c e s for Short versus Long Term Androgen Deprivation and R a d i o t h e r a p y in P r o s t a t e Cancer Survivors
D. Wilke 1, M. Krahn 2, P, Warde 3, A. Bezjak 3, G. Tomlinson 2, R. Rutledge 1, A. Detsky 4 Nova Scotia Cancer Centre, Dalhousie University, Halifax, Nova Scotia1; University Health Network, University of Toronto, Toronto, Ontario2; Princess Margaret Hospital, University of Toronto, Toronto, Ontario3; Mount Sinai Hospital, University of Toronto, Toronto, Ontario 4 Background: Given a hypothetical scenario, patients may be willing to trade-off survival in order to be spared the side effects of long-term versus short-term androgen deprivation (AD) and radiotherapy for the treatment of Locally Advanced Prostate Cancer. Methods: Sixty-seven prostate cancer survivors who were treated with radiotherapy participated in a structured interview. Current sexual function was assessed using the International Index of Erectile Function (IIEF) and their current prostate cancer-specific health state was assessed using the prostate cancer health state classification system of the Patient Oriented Prostate Utility Scale (PORPUS). Preferences for long versus short-term AD and radiotherapy were elicited using the Probability trade-off (PTO) technique. Results: Given a hypothetical scenario, prostate cancer survivors were willing, on average, to trade off 8.3% [95% C.I.: 7.1 - 9,3%] absolute prostate cancer- specific survival (PCSS) to avoid long-term versus short-term AD. As per RTOG 9202, long versus short-term AD and radiotherapy provides only a 3.4% benefit in PCSS at 5 years. When given the scenario of no improvement in overall survival, patients were still willing to trade survival, but required, on average, an additional 1.5% gain in PCSS (p<0.0001). Willingness to trade survival, using the PTO technique, was correlated with current sexual desire, as measured by the sexual desire domain score of the IIEF (Spearman Rank r=0.5, p<0.0001). Sexual desire domain score remained significant on multivariable analysis of factors related to willingness to trade survival. Conclusion: Prostate cancer survivors are, in theory, willing to trade survival in order to be spared the side effects of long versus short-term androgen deprivation. Sexual desire is correlated with willingness to trade PCSS. 2O The D u r a t i o n of LHRH T r e a t m e n t in Men Radical R a d i o t h e r a p y for P r o s t a t e Cancer
Receiving
P. Blood 1, C. Paul2, ]. Barnett 3, ]. Spinelli~, T. Pickles ~, G. Steinhoff ~ British Columbia Cancer Agency, University of British Columbia, Victoria, British Columbia1; University of British Columbia, Vancouver, British Columbia2; British Columbia Cancer Agency, Victoria, British Columbia3; Gary Steinhoff Clinical Research, Victoria, British Columbia 4 Rationale: Since 1997, randomized trials have shown improved outcomes when LHRH treatment is added to radical radiotherapy for selected patients with prostate cancer. However, there is a wide variation in the duration of LHRH treatment in these studies, from 4 months to 3 years. Little information is available on the extent to which men with prostate cancer are being treated with LHRH injections in this setting. Objectives: To measure the extent to which men receiving radical radiation treatment for prostate cancer are receiving LHRH treatment; by determining the proportion of men receiving LHRH prescriptions and the duration of LHRH prescriptions associated with radical radiation treatment. Methods: A cohort of men diagnosed with prostate cancer between 1986 and 2000 was assembled from the Provincial Cancer Registry. The start date of radiation treatment was
CARO 2005
September 7-10
identified for those men who received radical radiation treatment. LHRH prescriptions dispensed between one year before and three years after the start date of radical radiation treatment were identified from the pharmacy records in the Cancer Registry. Results: 34,521 men were diagnosed with prostate cancer between 1986 and 2000 and 11,787 of these men received radical radiation treatment. 3,098 of the men who received radical radiation treatment also received LHRH injections. The mean duration of LHRH injections for men treated with radical radiation in 2000 was 15 months (standard deviation 10 months) and the median was 12 months. The proportion of men dispensed LHRH injections in association with radical radiation treatment increased from less than 9% in 1995 to 71% in 2000. Conclusions: LHRH treatment is administered to the majority of men who currently receive radical radiation treatment for prostate cancer. There is a wide variation in the duration of LHRH treatment, which reflects the uncertainty in the evidence available on the optimal duration of adjuvant LHRH treatment. 21 Testosterone and Erectile Function Recovery After Radiotherapy and Long - Term Androgen Deprivation With LHRH Analogues D. Wilke I, C. Parker e, A. Andronowski I, D. Tsuji3, C. Carton 3, M. Gospodarowicz 3, P. Warde 3 Nova Scotia Cancer Centre, Dalhousie University, Halifax, Nova Scotia1; Royal Marsden Hospital, United Kingdom2; Princess Margaret Hospital, University of Toronto, Toronto, Ontario 3
Background: There is a paucity of data regarding the return of sexual function and recovery of testosterone in patients who have had radiotherapy and Iongterm adjuvant androgen deprivation. Methods: Patients at a major cancer center who had completed radiotherapy and Iongterm adjuvant androgen deprivation (3 years) with an LHRH agonist were approached to participate. Patients completed the International index of erectile function (IIEF) and had Serum levels of Testosterone (I-F), Luteinizing hormone (LH), Follicle stimulating hormone, Prostate specific antigen, and Hemoglobin measured. Assessments were repeated at one year. Results: Twenty patients were accrued from April 2000 to July 2001. Median age at entry into the study was 71 (range 55 to 81). Mean pretreatment serum TT was 10.6 nmol/L (range 0.3 to 16.6). At entry, the mean serum I F was 4.4 nmol/L (range 0.4 to 16), and at 1 year, increased to a mean value of 7.7 nmol/L (range 1.1 to 20.4) (p=0.0005). Prior to treatment, 11 out of 20 patients were potent. There was no significant improvement in any domain score of the IIEF over the one year time period. Median duration of castrate levels of-IF (<1.7 nmol/L) from cessation of androgen deprivation was 8 months. Using a cutoff of 8.0 nmol/L, the median duration of subnormal levels of I F was 2.3 years, and at 4.2 years 25% of patients had a persistently subnormal 1-1. Median duration of subnormal levels of LH was 3.8 months. Prognostic factors related to -I-I recovery were: Age and LH/-I-I ratio. Time to recovery of LH was sooner than TT (p<0.0001), suggesting the delay to recovery is at the level of the testicle. Two patients regained erectile function sufficient for intercourse. Conclusion: Testosterone levels improved over time, but remained subnormal years after cessation of treatment. Return of sexual function occurred in a minority of patients. 22 Development and Psychometric Properties of Prostate Cancer Radiation Toxicity Questionnaire
the
G. Rodrigues, M. Lock, D. O'Souza, ]. Radwan, R. Ash, V. Venkatsean, G. Bauman London Regional Cancer Program, University of Western Ontario, London, Ontario
$7
Introduction: The objective of this study was to construct a prostate cancer late radiation toxicity (PCRT) questionnaire with associated health-related quality of life (HRQoL) domains. Methods: An initial questionnaire was subjected to both patient (n=8) and expert (n=7) opinion. A pilot study (n=37) assessed patient feedback, ease of administration, and acceptance. Item reduction (n=100) based on response heterogeneity, factor analysis and Cronbach's alpha analysis was performed. Reliability testing (n=274) was performed using test-retest methodology and calculation of intraclass correlation coefficients (CC). Validity testing (n=274) consisted of discriminant and various construct validity tests 1. calculation of Pearson CC between the PCRT and different HRQoL instruments, and 2. comparison of mean brachytherapy versus external-beam radiation therapy domain scores by Student's t-test). Results: The pilot study demonstrated that the PCRT was comprehensive (94%) and easy to administer (1.3% missing data). Item reduction resulted in three HRQoL subscales: (4 item GU alpha = 0.639, 12 item GI = 0.859, 5 item sexual = 0.700). Test-retest reliability demonstrated intraclass correlation coefficients of 0.811 (GU), 0.842 (GI), and 0.740 (sexual). Discriminate validity analysis demonstrated Pearson CC of 0.449 (GU-GI), 0.200 (sexuaI-GU), and 0.09 (sexuaI-GI). Content validity analysis demonstrated significant correlations between analogous subscales between PCRT and the PCQoL (range 0.35-0.78). Smaller correlations exist between the PCRT and FACT-G (0.19-0.39) and SF-36 (0.03-0.34). Difference scores between brachytherapy and external-beam favoured brachytherapy [4.13 (GI, p=0.02), 3.50 (sexual, p=0.36), and 3.63 (GU, p=0.14)]. Conclusions: The HRQoL subscales generated from the PCRT have been shown to have good internal consistency with documented reliability and validity. 23 Patient-Reported Late Toxicity Following High-dose Radiation Therapy for Prostate Cancer: The Princess Margaret Hospital Experience
M. Skala, C. Catton, L. Divanbeigi, A. Bayley, R. Bristow, P. Catton, J. Crook, M. Gospodarowicz, M. McLean, M. Milosevic, G. Lockwood, T. Rosewall, P. Warde Princess Margaret Hospital, University of Toronto, Toronto, Ontario Objective: To determine the patient-reported incidence of late gastro-intestinal (GI) and genito-urinary (GU) toxicity following high-dose radiation therapy at the Princess Margaret Hospital (PMH). Methods: We sent a validated late toxicity postal questionnaire to 754 men with T1-T2 prostate cancer, who received 75.6 Gy or 79.8 Gy to the prostate gland using 3DCRT or IMRT between 1997 and 2003. All patients were treated with daily image guidance. Three fiducial markers were inserted into the prostate gland before treatment planning, to allow daily target verification. Patient reported toxicity was graded using the modified RTOG-LENT scoring system. Results: 416 (55%) men answered the questionnaire. At a median follow-up of 3.5 years, the incidence of RTOG Grade 0 late GI toxicity was 75%, Grade 1-23%, Grade 2-1.2% and Grade 3-1.0%. Four patients experienced Grade 3 GI toxicity. Two reported prolonged use of steroid per enema, one reported persistent use of incontinence pads, and one underwent numerous coagulation procedures. The incidence of RTOG Grade 0 late GU toxicity was 71%, Grade 1-23%, Grade 24.3% and Grade 3-1.0%. Four patients experienced Grade 3 GU toxicity. Three reported persistent use of incontinence pads, and one experienced nocturia more frequently than every hour. Patient-reported pre-treatment potency rate was 73%. Following treatment, 46% of previously potent men were able to achieve erections sufficient for intercourse at least 50% the time. 18% reported use of PDE-5 inhibitors, and 83% found these to be effective.