Seven-Year Outcomes Following Accelerated Partial Breast Irradiation Stratified by ASTRO Consensus Groupings.

OBJECTIVES: Limited long-term data exist regarding outcomes for patients treated with accelerated partial breast irradiation (APBI), particularly, when stratified by American Society for Radiation Oncology (ASTRO) Consensus Statement (CS) risk groups. The purpose of this analysis is to present 5- and 7-year outcomes following APBI based on CS groupings. MATERIALS AND METHODS: A total of 690 patients with early-stage breast cancer underwent APBI from 1993 to 2012, receiving interstitial brachytherapy (n=195), balloon-based brachytherapy (n=290), or 3-dimensional conformal radiotherapy (n=205) at a single institution. Patients were stratified into suitable, cautionary, and unsuitable groups with 5-year outcomes analyzed. Seven-year outcomes were analyzed for a subset with follow-up of ≥2 years (n=625). RESULTS: Median follow-up was 6.7 years (range, 0.1 to 20.1 y). Patients assigned to cautionary and unsuitable categories were more likely to have high-grade tumors (21% to 25% vs. 9%, P=0.001), receive chemotherapy (15% to 38% vs. 6%, P<0.001), and have close/positive margins (9% to 11% vs. 0%, P<0.001). There was no difference in ipsilateral breast tumor recurrence at 5 or 7 years: 2.2%, 1.2%, 2.8% at 5 years (P=0.57), and 2.2%, 1.9%, 4.6% at 7 years (P=0.58) in the suitable, cautionary, and unsuitable groups, respectively. As compared with the suitable group, increased rates of distant metastases were noted for the unsuitable and cautionary groups at 5 years (P=0.04). CONCLUSIONS: No differences in rates of ipsilateral breast tumor recurrence were seen at 5 or 7 years when stratified by ASTRO CS groupings. Modest increases in distant recurrence were noted in the cautionary and unsuitable groups. These findings suggest that the ASTRO CS groupings stratify more for systemic recurrence and may not appropriately select patients for whole versus partial breast irradiation.

Comparison of dose-escalated, image-guided radiotherapy vs. dose-escalated, high-dose-rate brachytherapy boost in a modern cohort of intermediate-risk prostate cancer patients.

PURPOSE: We compared outcomes in intermediate-risk prostate cancer patients treated with dose-escalated adaptive image-guided radiation therapy (IGRT) or dose-escalated high-dose-rate brachytherapy boost (HDR-B). METHODS AND MATERIALS: Patients with intermediate-risk prostate cancer by National Comprehensive Cancer Network criteria were treated with either CT-based off-line adaptive IGRT (n = 734) or HDR-B (n = 282). IGRT was delivered with 3D-conformal or intensity-modulated radiation therapy with a median dose of 77.4 Gy. For HDR-B, the whole pelvis received a median 46 Gy, and the prostate 2 implants of 9.5 Gy (n = 71), 10.5 Gy (n = 155), or 11.5 Gy (n = 56). RESULTS: Median followup was 3.7 years for IGRT and 8.0 years for HDR-B (p < 0.001). Eight-year biochemical control was 86% for IGRT and 91% for HDR-B (p = 0.22), disease-free survival 67% for IGRT and 79% for HDR-B (p = 0.006), and overall survival 75% for IGRT and 86% for HDR-B (p = 0.009). Cause-specific survival (8-year, 100% vs. 99%), freedom from distant metastases (98% vs. 97%), and freedom from local recurrence (98% vs. 98%) did not differ (p > 0.50 each). A worse prognosis group was defined by percent positive prostate biopsy cores >50%, perineural invasion, or stage T2b-c, encompassing 260 (35%) IGRT and 171 (61%) HDR-B patients. These patients evidenced a 5-year biochemical control of 96% for HDR-B and 87% for IGRT (p = 0.002). CONCLUSIONS: Dose-escalated IGRT and HDR-B both yield excellent clinical outcomes for patients with intermediate-risk prostate cancer. Improved biochemical control with HDR-B for patients with worse pretreatment characteristics suggests that a subgroup of intermediate-risk prostate cancer patients may benefit from dual-modality treatment.

An age-corrected matched-pair study of erectile function in patients treated with dose-escalated adaptive image-guided intensity-modulated radiation therapy vs. high-dose-rate brachytherapy for prostate cancer.

PURPOSE: To compare erectile dysfunction (ED) after adaptive dose-escalated image-guided intensity-modulated radiotherapy (IG-IMRT) and high-dose-rate interstitial brachytherapy (HDR) monotherapy. METHODS AND MATERIALS: Low- and intermediate-risk prostate cancer patients treated with IG-IMRT or HDR were matched on pretreatment ED, age, Gleason score, T-stage, and prostate specific antigen. Patients who received androgen deprivation therapy were excluded. ED was graded by Common Terminology Criteria for Adverse Events v4. Actuarial rates of ED were computed by the Kaplan-Meier method. RESULTS: There were 384 patients with median followup of 2.0 years (0.5-6.1) for IG-IMRT and 2.0 years (0.5-8.7) for HDR. The median IG-IMRT dose was 75.6 Gy and HDR dose 38 Gy in four fractions. For patients with no pretreatment ED, actuarial rates of requiring intervention (Grade ≥2 ED) at 3 years were 31% for IG-IMRT and 19% for HDR (p=0.23), and impotence despite medical intervention (Grade 3) were 0% for IG-IMRT and 6% for HDR (p=0.06). For patients with Grade 1 pretreatment ED, Grade ≥2 ED at 3 years were 47% for IG-IMRT and 34% for HDR (p=0.79), and Grade 3 ED were 15% in both groups (p=0.59). For patients with Grade 2 pretreatment ED, Grade 3 ED at 3 years were 22% for IG-IMRT and 37% for HDR (p=0.70). No variables were predictive of Grade ≥2 ED following treatment. CONCLUSIONS: Rates of ED requiring medical intervention for both IG-IMRT and HDR are low and equivalent. Even patients with ED before treatment are likely to maintain potency with medication use at 3 years following treatment.

Chromogranin A staining as a prognostic variable in newly diagnosed Gleason score 7-10 prostate cancer treated with definitive radiotherapy.

PURPOSE: To demonstrate the association of neuroendocrine differentiation, as identified by chromogranin A (CgA) staining, with clinical outcomes in newly diagnosed prostatic adenocarcinoma treated with definitive radiotherapy (RT). MATERIALS/METHODS: Patients with Gleason score ≥7 adenocarcinoma were identified from our outcomes database. RT consisted of external beam, brachytherapy, or external beam with brachytherapy boost. Biopsy specimens were stained for neuroendocrine differentiation with CgA. Results were interpreted by a single pathologist. CgA staining was quantified as 0%, <1%, 1-10%, or >10% of tumor cells. Clinical outcomes were blinded at the time of pathologic evaluation. RESULTS: CgA staining was performed on 289 patients. 149 patients had Gleason score 7, and 140 were Gleason score 8-10. Median follow-up was 6.5 years. For patients with <1% versus >1% CgA staining, pretreatment characteristics were well-balanced. CgA staining was detected in 90 cases (31%). 58 patients had focal positive (<1%) CgA staining, and 32 cases had >1% of tumor cells CgA positive. Patients with >1% CgA staining had inferior biochemical control, clinical failure, distant metastases (DM), and cause-specific survival (CSS) rates. Ten-year rates of DM were 8% versus 48% for patients with <1% versus >1% CgA positive cells, respectively (P < 0.001). CSS at 10 years was 95% versus 76%, respectively (P < 0.001). Local control was equivalent in the two patient cohorts. Patients with <1% CgA staining had similar outcomes to those patients with 0% staining. CONCLUSIONS: Neuroendocrine differentiation involving >1% of tumor cells on prostate cancer biopsies is a predictor of DM and CSS in patients treated with primary RT.

Comparison of acute and late toxicities for three modern high-dose radiation treatment techniques for localized prostate cancer.

PURPOSE: We compared acute and late genitourinary (GU) and gastrointestinal (GI) toxicities in prostate cancer patients treated with three different high-dose radiation techniques. METHODS AND MATERIALS: A total of 1,903 patients with localized prostate cancer were treated with definitive RT at William Beaumont Hospital from 1992 to 2006: 22% with brachytherapy alone (BT), 55% with image-guided external beam (EB-IGRT), and 23% external beam with high-dose-rate brachytherapy boost (EBRT+HDR). Median dose with BT was 120 Gy for LDR and 38 Gy for HDR (9.5 Gy × 4). Median dose with EB-IGRT was 75.6 Gy (PTV) to prostate with or without seminal vesicles. For EBRT+HDR, the pelvis was treated to 46 Gy with an additional 19 Gy (9.5 Gy × 2) delivered via HDR. GI and GU toxicity was evaluated utilizing the NCI-CTC criteria (v.3.0). Median follow-up was 4.8 years. RESULTS: The incidences of any acute ≥ Grade 2 GI or GU toxicities were 35%, 49%, and 55% for BT, EB-IGRT, and EBRT+HDR (p < 0.001). Any late GU toxicities ≥ Grade 2 were present in 22%, 21%, and 28% for BT, EB-IGRT, and EBRT+HDR (p = 0.01), respectively. Patients receiving EBRT+HDR had a higher incidence of urethral stricture and retention, whereas dysuria was most common in patients receiving BT. Any Grade ≥ 2 late GI toxicities were 2%, 20%, and 9% for BT, EB-IGRT, and EBRT+HDR (p < 0.001). Differences were most pronounced for rectal bleeding, with 3-year rates of 0.9%, 20%, and 6% (p < 0.001) for BT, EB-IGRT, and EBRT+HDR respectively. CONCLUSIONS: Each of the three modern high-dose radiation techniques for localized prostate cancer offers a different toxicity profile. These data can help patients and physicians to make informed decisions regarding radiotherapy for prostate andenocarcinoma.

Identifying differences between biochemical failure and cure: incidence rates and predictors.

BACKGROUND: Patients treated with radiation therapy (RT) for prostate cancer were evaluated to estimate the length of time required to document biochemical cure (BC) after treatment and the variables associated with long-term treatment efficacy. PATIENTS AND METHODS: 2,100 patients received RT alone for localized prostate carcinoma (external-beam RT, n = 1,504; brachytherapy alone, n = 241; or brachytherapy + pelvic radiation, n = 355). The median external-beam dose was 68.4 Gy, and the median follow-up time was 8.6 years. Biochemical failure (BF) was defined according to the Phoenix definition. RESULTS: Biochemical failure was experienced by 685 patients (32.6%). The median times to BF for low-, intermediate-, and high-risk groups were 6.0, 5.6, and 4.5 years respectively (p < 0.001). The average annual incidence rates of BF for years 1-5, 5-10,11-15, and 16-20 in low-risk patients were 2.0%, 2.0%, 0.3%, and 0.06% (p < 0.001); for intermediate-risk patients, 4%, 3%, 0.3%, and 0% (p < 0.001); and for high-risk patients, 10.0%, 5.0%, 0.3%, and 0.3% (p < 0.001). After 5 years of treatment, 36.9% of all patients experienced BF. The percentage of total failures occurring during years 1-5, 5-10, 11-15, and 16-20 were 48.7%, 43.5%, 6.5%, and 1.3% for low-risk patients; 64.0%, 32.2%, 3.8%, and 0% for intermediate-risk patients; and 71.9%, 25.9%, 1.1%, and 1.1% for high-risk patients, respectively. Increasing time to nadir was associated with increased time to BF. On multivariate analysis, factors significantly associated with 10-year BC included prostate-specific antigen nadir and time to nadir. CONCLUSIONS: The incidence rates for BF did not plateau until later than 10 years after treatment, suggesting that extended follow-up time is required to monitor patients after treatment. Prostate-specific antigen nadir and time to nadir have the strongest association with long-term BC.

Prognostic significance of neuroendocrine differentiation in patients with Gleason score 8-10 prostate cancer treated with primary radiotherapy.

PURPOSE: To determine the prognostic significance of neuroendocrine differentiation (NED) in Gleason score 8-10 prostate cancer treated with primary radiotherapy (RT). METHODS AND MATERIALS: Chromogranin A (CgA) staining was performed and overseen by a single pathologist on core biopsies from 176 patients from the William Beaumont prostate cancer database. A total of 143 had evaluable biopsy material. Staining was quantified as 0%, <1%, 1-10%, or >10% of tumor cells. Patients received external beam RT alone or together with high-dose-rate brachytherapy. Cox regression and Kaplan-Meier estimates determined if the presence/frequency of neuroendocrine cells correlated with clinical endpoints. RESULTS: Median follow-up was 5.5 years. Forty patients (28%) had at least focal positive CgA staining (<1% n = 21, 1-10% n = 11, >10% n = 8). No significant differences existed between patients with or without staining in terms of age, pretreatment prostate-specific antigen, tumor stage, hormone therapy administration, % biopsy core involvement, mean Gleason score, or RT dose/modality. CgA staining concentration independently predicted for biochemical and clinical failure, distant metastases (DM), and cause-specific survival (CSS). For patients with <1% vs. >1% staining, 10-year DM rates were 13.4% vs. 55.3%, respectively (p = 0.001), and CSS was 91.7% vs. 58.9% (p < 0.001). As a continuous variable, increasing CgA staining concentration predicted for inferior rates of DM, CSS, biochemical control, and any clinical failure. No differences in outcomes were appreciated for patients with 0% vs. <1% NED. CONCLUSIONS: For Gleason score 8-10 prostate cancer, >1% NED is associated with inferior clinical outcomes for patients treated with radiotherapy. This relates most directly to an increase in distant disease failure.

Lack of benefit for the addition of androgen deprivation therapy to dose-escalated radiotherapy in the treatment of intermediate- and high-risk prostate cancer.

PURPOSE: Assessment of androgen deprivation therapy (ADT) benefits for prostate cancer treated with dose-escalated radiotherapy (RT). METHODS AND MATERIALS: From 1991 to 2004, 1,044 patients with intermediate- (n = 782) or high-risk (n = 262) prostate cancer were treated with dose-escalated RT at William Beaumont Hospital. Patients received external-beam RT (EBRT) alone, brachytherapy (high or low dose rate), or high dose rate brachytherapy plus pelvic EBRT. Intermediate-risk patients had Gleason score 7, prostate-specific antigen (PSA) 10.0-19.9 ng/mL, or Stage T2b-T2c. High-risk patients had Gleason score 8-10, PSA ≥20, or Stage T3. Patients were additionally divided specifically by Gleason score, presence of palpable disease, and PSA level to further define subgroups benefitting from ADT. RESULTS: Median follow-up was 5 years; 420 patients received ADT + dose-escalated RT, and 624 received dose-escalated RT alone. For all patients, no advantages in any clinical endpoints at 8 years were associated with ADT administration. No differences in any endpoints were associated with ADT administration based on intermediate- vs. high-risk group or RT modality when analyzed separately. Patients with palpable disease plus Gleason ≥8 demonstrated improved clinical failure rates and a trend toward improved survival with ADT. Intermediate-risk patients treated with brachytherapy alone had improved biochemical control when ADT was given. CONCLUSION: Benefits of ADT in the setting of dose-escalated RT remain poorly defined. This question must continue to be addressed in prospective study.

Predictors for chronic urinary toxicity after the treatment of prostate cancer with adaptive three-dimensional conformal radiotherapy: dose-volume analysis of a phase II dose-escalation study.

PURPOSE: To identify factors predictive for chronic urinary toxicity secondary to high-dose adaptive three-dimensional conformal radiation. METHODS AND MATERIALS: From 1999 to 2002, 331 consecutive patients with clinical Stage II-III prostate cancer were prospectively treated (median dose, 75.6 Gy). The bladder was contoured, and the bladder wall was defined as the outer 3 mm of the bladder solid volume. Toxicity was quantified according to the National Cancer Institute Common Toxicity Criteria 2.0. Median follow-up was 1.6 years. RESULTS: The 3-year rates of Grade > or =2 and Grade 3 chronic urinary toxicity were 17.0% and 3.6%, respectively. Prostate volume, confidence-limited patient-specific planning target volume, bladder wall volume, and acute urinary toxicity were all found to be accurate predictors for chronic urinary toxicity. The volume of bladder wall receiving > or =30 Gy (V30) and > or =82 Gy (V82), along with prostate volume, were all clinically useful predictors of Grade > or =2 and Grade 3 chronic urinary toxicity and chronic urinary retention. Both Grade > or =2 (p = 0.001) and Grade 3 (p = 0.03) acute urinary toxicity were predictive for the development of Grade > or =2 (p = 0.001, p = 0.03) and Grade 3 (p = 0.05, p < 0.001) chronic urinary toxicity. On Cox multivariate analysis the development of acute toxicity was independently predictive for the development of both Grade > or =2 and Grade 3 chronic urinary toxicity. CONCLUSIONS: Acute urinary toxicity and bladder wall dose-volume endpoints are strong predictors for the development of subsequent chronic urinary toxicity. Our recommendation is to attempt to limit the bladder wall V30 to <30 cm(3) and the V82 to <7 cm(3) when possible. If bladder wall information is not available, bladder solid V30 and V82 may be used.

The impact of age on long-term outcome in patients with endometrial cancer treated with postoperative radiation.

PURPOSE: Endometrial cancer is the most commonly diagnosed gynecologic malignancy in the United States. Age has been associated with worse outcome in univariate analysis. However, the patterns of failure and associated risk factors in older patients remain unclear. We reviewed our institution's experience to assess the effect of age in a population of endometrial cancer patients treated with surgery and adjuvant radiation therapy. METHODS: From 1992-2002, 243 endometrial cancer patients underwent a total abdominal hysterectomy and adjuvant radiation. Forty-nine patients with stage I-II (occult) endometrial adenocarcinoma (no clear cell or serous papillary) were treated postoperatively with vaginal intracavitary high-dose rate (HDR) brachytherapy alone using Iridium-192 (median dose 30 Gy) to a median length of 4 cm. Forty-eight patients with stage I-III endometrial adenocarcinoma (no clear cell or papillary serous) were treated with postoperative pelvic RT (median dose 45 Gy) and intracavitary HDR brachytherapy (median dose 20 Gy). One hundred forty-six patients underwent postoperative whole abdomino-pelvic irradiation (WAPI) secondary to unfavorable histology (clear cell or serous papillary) or two of the following: deep myometrial invasion, grade 3, or FIGO stage III. Age was analyzed as a continuous and a categorical variable. The age of 63 year split the age group using various statistical analyses. RESULTS: Median follow-up of all patients was 4.2 years. Patients grouped by age of < or =63 years or older had similar FIGO stage (P = 0.5), grade (P = 0.09), treatment modality (P = 0.7), and lymphovascular space invasion (LVSI) (P = 0.6). Twenty-five percent (60/243) of patients developed recurrence. Of these failures, 15% (15/102) were age < or =63 years and 32% (45/141) were age >63 years at diagnosis (P = 0.02). For all patients, the 5-year event-free survival (EFS), cause specific survival (CSS), and overall survival (OS) were 64%, 82%, and 72%, respectively. Five-year EFS for patients age < or =63 years and >63 years was 76% vs. 55% (P < 0.001). Five-year OS for age < or =63 years and >63 years was 85% vs. 63% (P < 0.001). Five-year CSS for age < or =63 years and >63 years was 91% vs. 75% (P = 0.003). Various factors were analyzed to determine an association with age. Older patients with stage III-IVA had significantly more failures than patients less than age 63 (P = 0.002). Older patients (>63 years) were found to have serous papillary histology (28%) more often than younger patients (15%) (P = 0.02). Greater depth of invasion was associated with older age (P = 0.01). On univariate analysis, older age (P = 0.003), LVSI (P = 0.002), FIGO stage (P < 0.001), grade (P < 0.001), and depth of invasion (P = 0.03) predicted for failure. On Cox multivariate analysis, older age (P = 0.006, HR 2.83), higher FIGO stage (P = 0.001, HR 1.96), and higher grade (P = 0.002, HR 2.66) were significant prognostic factors for recurrence. No difference was seen between the two age groups from date of surgery and start of radiation. The duration of therapy was not different between the two groups. CONCLUSIONS: Older endometrial cancer (age >63 years) patients have a significantly decreased overall survival, cause-specific survival, and greater risk of recurrence following postoperative RT independent of other prognostic factors and/or treatment technique. The impact of treatment-related variables did not alter the age-related outcome.

Phase II dose escalation study of image-guided adaptive radiotherapy for prostate cancer: use of dose-volume constraints to achieve rectal isotoxicity.

PURPOSE: In our Phase II prostate cancer Adaptive Radiation Therapy (ART) study, the highest possible dose was selected on the basis of normal tissue tolerance constraints. We analyzed rectal toxicity rates in different dose levels and treatment groups to determine whether equivalent toxicity rates were achieved as hypothesized when the protocol was started. METHODS AND MATERIALS: From 1999 to 2002, 331 patients with clinical stage T1 to T3, node-negative prostate cancer were prospectively treated with three-dimensional conformal adaptive RT. A patient-specific confidence-limited planning target volume was constructed on the basis of 5 CT scans and 4 sets of electronic portal images after the first 4 days of treatment. For each case, the rectum (rectal solid) was contoured in its entirety. The rectal wall was defined by use of a 3-mm wall thickness (median volume: 29.8 cc). The prescribed dose level was chosen using the following rectal wall dose constraints: (1) Less than 30% of the rectal wall volume can receive more than 75.6 Gy. (2) Less than 5% of the rectal wall can receive more than 82 Gy. Low-risk patients (PSA < 10, Stage < or = T2a, Gleason score < 7) were treated to the prostate alone (Group 1). All other patients, intermediate and high risk, where treated to the prostate and seminal vesicles (Group 2). The risk of chronic toxicity (NCI Common Toxicity Criteria 2.0) was assessed for the different dose levels prescribed. HIC approval was acquired for all patients. Median follow-up was 1.6 years. RESULTS: Grade 2 chronic rectal toxicity was experienced by 34 patients (10%) (9% experienced rectal bleeding, 6% experienced proctitis, 3% experienced diarrhea, and 1% experienced rectal pain) at a median interval of 1.1 year. Nine patients (3%) experienced grade 3 or higher chronic rectal toxicity (1 Grade 4) at a median interval of 1.2 years. The 2-year rates of Grade 2 or higher and Grade 3 or higher chronic rectal toxicity were 17% and 3%, respectively. No significant difference by dose level was seen in the 2-year rate of Grade 2 or higher chronic rectal toxicity. These rates were 27%, 15%, 14%, 17%, and 24% for dose levels equal to or less than 72, 73.8, 75.6, 77.4, and 79.2 Gy, respectively (p = 0.3). Grade 2 or higher chronic rectal bleeding was significantly greater for Group 2 than for Group 1, 17% vs. 8% (p = 0.035). CONCLUSIONS: High doses (79.2 Gy) were safely delivered in selected patients by our adaptive radiotherapy process. Under the rectal dose-volume histogram constraints for the dose level selection, the risk of chronic rectal toxicity is similar among patients treated to different dose levels. Therefore, rectal chronic toxicity rates reflect the dose-volume cutoff used and are independent of the actual dose levels. On the other hand, a larger PTV will increase the rectal wall dose and chronic rectal toxicity rates. PTV volume and dose constraints should be defined, considering their potential benefit.

Dose-volume analysis of predictors for chronic rectal toxicity after treatment of prostate cancer with adaptive image-guided radiotherapy.

PURPOSE: We analyzed our experience treating localized prostate cancer with image-guided off-line correction with adaptive high-dose radiotherapy (ART) in our Phase II dose escalation study to identify factors predictive of chronic rectal toxicity. MATERIALS AND METHODS: From 1999-2002, 331 patients with clinical stage T1-T3N0M0 prostate cancer were prospectively treated in our Phase II 3D conformal dose escalation ART study to a median dose of 75.6 Gy (range, 63.0-79.2 Gy), minimum dose to confidence limited-planning target volume (cl-PTV) in 1.8 Gy fractions (median isocenter dose = 79.7 Gy). Seventy-four patients (22%) also received neoadjuvant/adjuvant androgen deprivation therapy. A patient-specific cl-PTV was constructed using 5 computed tomography scans and 4 sets of electronic portal images by applying an adaptive process to assure target accuracy and minimize PTV margin. For each case, the rectum (rectal solid) was contoured from the sacroiliac joints or rectosigmoid junction (whichever was higher) to the anal verge or ischial tuberosities (whichever was lower), with a median volume of 81.2 cc. The rectal wall was defined using the rectal solid with an individualized 3-mm wall thickness (median volume = 29.8 cc). Rectal wall dose-volume histogram was used to determine the prescribed dose. Toxicity was quantified using the National Cancer Institute Common Toxicity Criteria 2.0. Multiple dose-volume endpoints were evaluated for their association with chronic rectal toxicity. RESULTS: Median follow-up was 1.6 years. Thirty-four patients (crude rate = 10.3%) experienced Grade 2 chronic rectal toxicity at a median interval of 1.1 years. Nine patients (crude rate = 2.7%) experienced Grade > or =3 chronic rectal toxicity (1 was Grade 4) at a median interval of 1.2 years. The 3-year rates of Grade > or =2 and Grade > or =3 chronic rectal toxicity were 20% and 4%, respectively. Acute toxicity predicted for chronic: Acute Grade 2-3 rectal toxicity (p < 0.001) including any acute rectal Grade 2-3 tenesmus (p = 0.02) and pain (p = 0.008) were significant predictors of chronic Grade > or =2 rectal toxicity. Any acute rectal toxicity (p = 0.001), any acute tenesmus (p = 0.03), and any acute diarrhea (p < 0.001) were also found to be predictive for chronic toxicity, as continuous variables. Dose-volume histogram predicted for chronic toxicity: Rectal wall absolute and relative V50, V60, V66.6, V70, and V72 and rectal solid relative V60-V72 were significantly associated with chronic Grade > or =2 rectal toxicity both as categorical and continuous variables (t test, linear regression) and when divided into subgroups (chi-square table). The chronic rectal toxicity Grade > or =2 risk was 9%, 18%, and 25% for the rectal wall relative V70 <15%, 25%-40%, and >40% respectively. The volume of rectum or rectal wall radiated to > or =50 Gy was a strong predictor for chronic rectal toxicity. Nonpredictive factors: Rectal solid/wall absolute or relative volumes irradiated to < or =40 Gy, dose level, and use of androgen deprivation were not found predictive. CONCLUSIONS: In our ART dose escalation study, rectal wall or rectum relative > or =V50 are closely predictive for chronic rectal toxicity. If rectal dose-volume histogram constraints are used to select the dose level, the risk of chronic rectal toxicity will reflect the risk of toxicity of the selected constraint rather than the dose selected as found in our study using an adaptive process. To select the prescribed dose, different dose-volume histogram constraints may be used including the rectal wall V70. Patients experiencing acute rectal toxicity are more likely to experience chronic toxicity.

Computed tomography guided management of interfractional patient variation.

Interfractional patient variation occurs regularly and considerably during the radiotherapy course. Consequently, a generic but large planning target margin has to be applied when patient treatment plan design based on a single pre-treatment computed tomography scan is used to guide multifraction radiation treatment, which creates a major limiting factor for radiotherapy improvement. Planning target margins can be significantly reduced using multiple (or 4-dimensional) image feedback management in the routine treatment process. The most effective method in multiple-image feedback management of radiotherapy is the adaptive control methodology. The adaptive radiotherapy technique aims to customize each patient's treatment plan to patient-specific variation by evaluating and characterizing the systematic and random variations through image feedback and including them in adaptive planning. Adaptive radiotherapy will become a new treatment standard, in which a predesigned adaptive treatment strategy, including the schedules of imaging and replanning, will eventually replace the predesigned treatment plan in the routine clinical practice.

Vaginal brachytherapy alone: an alternative to adjuvant whole pelvis radiation for early stage endometrial cancer.

OBJECTIVE: Postoperative management of early stage adenocarcinoma of the endometrium remains controversial. The use of pelvic radiation therapy as shown by the Gynecologic Oncology Group (GOG)-99 trial improves the event free interval at the cost of increased toxicity. We reviewed and compared our results treating early stage endometrial adenocarcinoma using hypofractionated high dose rate (HDR) vaginal brachytherapy (VB) alone with the results of the GOG-99. METHODS: From 1992 to 2002, 243 endometrial cancer patients were treated with TAH/BSO and selective lymph node dissection followed by adjuvant radiotherapy (RT). Of these, 50 FIGO stage I-II (occult) adenocarcinoma (no clear cell or serous papillary) of the endometrium were managed with HDR hypofractionated VB as monotherapy using Iridium-192 to a dose of 30 Gy in 6 fractions twice weekly prescribed to a depth of 5 mm and median length of 4 cm. The characteristics, toxicity rates, and outcomes of our patients were compared with the results of the GOG-99. The median follow up of our patients and the GOG-99 were 3.2 years and 5.8 years, respectively. RESULTS: Patient characteristics including age, stage, and grade were similar in our study and the GOG-99. The local recurrence rate in our study, the pelvic RT arm of the GOG-99, and the no RT arm of the GOG-99 were 4% (n = 2), 2% (n = 3), and 9% (n = 18), respectively. In our study, one patient failed in the vagina alone and a second patient failed in the vagina and pelvis. In the GOG-99, the vagina as a component of locoregional failure was also the most common failure site in the no RT arm 77.8% (n = 14) and in the RT arm 100% (n = 3). The 2-year cumulative recurrence rate in our study was 2%, which compares favorably with the GOG-99 pelvic RT arm (3%) and observation arm (12%). Four-year survival rates of the no RT arm of the GOG-99, the RT arm of the GOG-99, and our study with HDR VB were 86%, 92%, and 97%, respectively. Chronic grade 2 toxicity rates were reduced by the use of VB compared to pelvic RT, especially GI toxicity 0% vs. 34% (P value < 0.001), and GI obstruction 0% vs. 7% (P value = 0.08). CONCLUSION: Stage I-II (occult) endometrial adenocarcinoma treated with postoperative HDR vaginal brachytherapy has similar overall survival, locoregional failure rates, and cumulative recurrence rates to standard fractionation external beam pelvic RT with the benefit of much lower toxicity rates and shorter overall treatment time.

Prostate gland motion assessed with cine-magnetic resonance imaging (cine-MRI).

PURPOSE: To quantify prostate motion during a radiation therapy treatment using cine-magnetic resonance imaging (cine-MRI) for time frames comparable to that expected in an image-guided radiation therapy treatment session (20-30 min). MATERIALS AND METHODS: Six patients undergoing radiation therapy for prostate cancer were imaged on 3 days, over the course of therapy (Weeks 1, 3, and 5). Four hundred images were acquired during the 1-h MRI session in 3 sagittal planes through the prostate at 6-s intervals. Eleven anatomic points of interest (POIs) have been used to characterize prostate/bony pelvis/abdominal wall displacement. Motion traces and standard deviation for each of the 11 POIs have been determined. The probability of displacement over time has also been calculated. RESULTS: Patients were divided into 2 groups according to rectal filling status: full vs. empty rectum. The displacement of POIs (standard deviation) ranged from 0.98 to 1.72 mm for the full-rectum group and from 0.68 to 1.04 mm for the empty-rectum group. The low standard deviations in position (2 mm or less) would suggest that these excursions have a low frequency of occurrence. The most sensitive prostate POI to rectal wall motion was the mid-posterior with a standard deviation of 1.72 mm in the full-rectum group vs. 0.79 mm in the empty-rectum group (p = 0.0001). This POI has a 10% probability of moving more than 3 mm in a time frame of approximately 1 min if the rectum is full vs. approximately 20 min if the rectum is empty. CONCLUSION: Motion of the prostate and seminal vesicles during a time frame similar to a standard treatment session is reduced compared to that reported in interfraction studies. The most significant predictor for intrafraction prostate motion is the status of rectal filling. A prostate displacement of <3 mm (90%) can be expected for the 20 min after the moment of initial imaging for patients with an empty rectum. This is not the case for patients presenting with full rectum. The determination of appropriate intrafraction margins in radiation therapy to accommodate the time-dependent uncertainty in positional targeting is a topic of ongoing investigations for the on-line image guidance model.

A dose-escalation trial with the adaptive radiotherapy process as a delivery system in localized prostate cancer: analysis of chronic toxicity.

PURPOSE: To evaluate the validity of the chosen adaptive radiotherapy (ART) dose-volume constraints while testing the hypothesis that toxicity would not be greater at higher tumor dose levels. MATERIALS AND METHODS: In the ART dose escalation/selection trial, treatment was initiated with a generic planning target volume (PTV) formed as a 1-cm expansion of the clinical target volume (CTV). After the first week of therapy, the patient was replanned with a patient-specific PTV, constructed with CT and electronic portal images obtained in the first 4 days of treatment. A new multileaf collimator beam aperture was used. A minimum dose prescribed to the patient-specific PTV, ranging 70.2-79.2 Gy, was determined on the basis of the following rectal and bladder constraints: <5% of the rectal wall has a dose >82 Gy, <30% of the rectal wall has a dose >75.6 Gy, <50% of the bladder volume has a dose >75.6 Gy, and the maximum bladder dose is 85 Gy. A conformal four-field and/or intensity-modulated radiotherapy (IMRT) technique was used. Independent reviewers scored toxicities. The worst toxicity score seen was used as per the Common Toxicity Criteria grade scale (version 2). We divided the patients into three separate groups: 70.2-72 Gy, >72-75.6 Gy, and >75.6-79.2 Gy. Toxicities in each group were quantified and compared by the Pearson chi-squared test to validate our dose escalation/selection model. Grades 0, 1, 2, and 3 were censored as none vs. each category and none vs. any. RESULTS: We analyzed patients with follow-up greater than 1 year. The mean duration of follow-up was 29 months (range, 12-46 months). We report on 280 patients, mean age 72 years (range, 51-87 years). Only 60 patients received adjuvant hormones. Mean pretreatment prostate-specific antigen level was 9.3 ng/mL (range, 0.6-120 ng/mL). Mean Gleason score was 6 (range, 3-9). The lowest dose level was given to 49 patients, the intermediate dose to 131 patients, and 100 patients received the highest dose escalation. One hundred eighty-one patients (65%) were treated to a prostate field only and 99 patients (35%) to prostate and seminal vesicles. Chronic genitourinary and/or gastrointestinal categories were incontinence, persistent urinary retention, increased urinary frequency/urgency, urethral stricture, hematuria, diarrhea, rectal pain, bleeding, ulcer, fistula, incontinence, and proctitis. Toxicity at the high dose level was not different from toxicity at the intermediate or lower dose levels. No significant difference was observed in any of the individual toxicity categories. CONCLUSIONS: By applying the ART process--namely, developing a patient-specific PTV--to prostate cancer patients, significant dose escalation can be achieved without increases in genitourinary or gastrointestinal toxicity. Our data validate the rectal and bladder dose-volume constraints chosen for our three-dimensional conformal and IMRT prostrate radiotherapy planning.

Improved outcome at 10 years for serous-papillary/clear cell or high-risk endometrial cancer patients treated by adjuvant high-dose whole abdomino-pelvic irradiation.

PURPOSE: The aim of the study was to evaluate the 10-year treatment outcome of utilizing adjuvant high-dose whole abdominal irradiation (WAPI technique) with a pelvic/vaginal boost in patients with stage I-III endometrial carcinoma at high risk for intra-abdominopelvic recurrence, including serous-papillary and clear cell histologies. MATERIAL AND METHODS: In a prospective nonrandomized trial, 132 patients were treated with adjuvant WAPI between November 1981 and October 2001. Forty-three patients (32%) were 1998 FIGO stage I-II and 89 (68%) were stage III. Pathological features included the following: 66 (52%) with deep myometrial invasion, 50 (38%) with positive peritoneal cytology, 89 (67%) with high-grade lesions, 25 (19%) with positive pelvic/para-aortic lymph nodes, and 58 (45%) with serous-papillary or clear cell histology. RESULTS: The mean follow up was 6.4 years (range 0.6-16.1). For the entire group, the 5- and 10-year cause-specific survival (CSS) was 77 and 72%, whereas the disease-free survival (DFS) was 55 and 45%. When stratified by histology the 5- and 10-year CSS for adenocarcinoma was 75 and 70%, while serous-papillary/clear cell was 80 and 74% (P = 0.314). The 5- and 10-year DFS for adenocarcinoma was 59 and 49%, whereas serous-papillary/clear cell was 49 and 38% (P = 0.563). For surgical stages I-II, the 5-year CSS was 83% for adenocarcinoma and 89% for serous-papillary (P = 0.353). For stage III, it was 73 and 62% (P = 0.318), respectively. Forty-six patients (35%) relapsed. The first site of failure was the abdomen/pelvis in 27/46 (59%). When stratified by histologic variant, 34% of patients with adenocarcinoma and 41% with serous-papillary developed recurrent disease. In multivariate regression analysis only advancing age was of prognostic significance for CSS (P = 0.025) and DFS (P = 0.026). Chronic grade 3/4 GI toxicity was seen in 14%, and 2% of patients developed grade 3 renal toxicity. CONCLUSION: High-dose adjuvant WAPI is very effective treatment with excellent 10-year results for stage I-III endometrial carcinoma with risk factors for intra-abdominopelvic recurrence, including serous-papillary or clear cell histology. The low long-term complication rate with high CSS makes high-dose WAPI the treatment of choice for these patients with significant comorbidities.

Ten-year outcome including patterns of failure and toxicity for adjuvant whole abdominopelvic irradiation in high-risk and poor histologic feature patients with endometrial carcinoma.

PURPOSE: To evaluate the long-term results of treatment using adjuvant whole abdominal irradiation (WAPI) with a pelvic/vaginal boost in patients with Stage I-III endometrial carcinoma at high risk of intra-abdominopelvic recurrence, including clear cell (CC) and serous-papillary (SP) histologic features. METHODS AND MATERIALS: In a prospective nonrandomized trial, 119 patients were treated with adjuvant WAPI between November 1981 and April 2000. All patients were analyzed, including those who did not complete therapy. The mean age at diagnosis was 66 years (range 39-88). Thirty-eight patients (32%) had 1989 FIGO Stage I-II disease and 81 (68%) had Stage III. The pathologic features included the following: 64 (54%) with deep myometrial invasion, 48 (40%) with positive peritoneal cytologic findings, 69 (58%) with high-grade lesions, 21 (18%) with positive pelvic/para-aortic lymph nodes, and 44 (37%) with SP or CC histologic findings. RESULTS: The mean follow-up was 5.8 years (range 0.2-14.7). For the entire group, the 5- and 10-year cause-specific survival (CSS) rate was 75% and 69% and the disease-free survival (DFS) rate was 58% and 48%, respectively. When stratified by histologic features, the 5- and 10-year CSS rate for adenocarcinoma was 76% and 71%, and for serous papillary/CC subtypes, it was 74% and 63%, respectively (p = 0.917). The 5- and 10-year DFS rate for adenocarcinoma was 60% and 50% and was 54% and 37% serous papillary/CC subtypes, respectively (p = 0.498). For surgical Stage I-II, the 5-year CSS rate was 82% for adenocarcinoma and 87% for SP/CC features (p = 0.480). For Stage III, it was 75% and 57%, respectively (p = 0.129). Thirty-seven patients had a relapse, with the first site of failure the abdomen/pelvis in 14 (38%), lung in 8 (22%), extraabdominal lymph nodes in 7 (19%), vagina in 6 (16%), and other in 2 (5%). When stratified by histologic variant, 32% of patients with adenocarcinoma and 30% with the SP/CC subtype developed recurrent disease. Most failures for either histologic group occurred within the abdominopelvic region. However, one-third of the adenocarcinoma recurrences were in the lung. Multivariate regression analysis (age, surgical stage, grade, myometrial invasion, histologic type, lymph node status, and peritoneal cytology) demonstrated age (p = 0.019) and surgical stage (p = 0.036) to be of prognostic significance for CSS; age (p = 0.036) was the only significant prognostic factor for DFS. Grade 1-2 gastrointestinal and hematologic acute toxicities were common. Asymptomatic bibasilar scarring on chest X-ray and mild elevation of liver enzymes were seen in almost 50% of the patients. Even though chronic toxicities were less frequent, 12% developed Grade 3-4 gastrointestinal and 2% Grade 3 renal toxicities. CONCLUSION: Adjuvant WAPI is very effective treatment with excellent 10-year results for Stage I-III endometrial carcinoma with risk factors for intra-abdominopelvic recurrence, including SP or CC histologic variants, deep myometrial invasion, high grade, nodal involvement, and positive peritoneal cytology. The low long-term complication rate with high CSS rate makes WAPI the treatment of choice for these patients with significant comorbidities.