Radiation therapy margin reduction for patients with localized prostate cancer: A prospective study of the dosimetric impact and quality of life

OBJECTIVES

To investigate the impact of reducing Clinical Target Volume (CTV) to Planning Target Volume (PTV) margins on delivered radiation therapy (RT) dose and patient reported quality-of-life (QOL) for patients with localized prostate cancer.

METHODS

Twenty patients were included in a single institution IRB-approved prospective study. Nine were planned with reduced margins (4 mm at prostate/rectum interface, 5 mm elsewhere), and 11 with standard margins (6/10 mm). Cumulative delivered dose was calculated using deformable dose accumulation. Each daily CBCT dataset was deformed to the planning CT (pCT), dose was computed, and accumulated on the resampled pCT using a parameter-optimized, B-spline algorithm (Elastix, ITK/VTK). EPIC-26 patient reported QOL was prospectively collected pre-treatment, post-treatment, and at 2-, 6-, 12-, 18-, 24-, 36-, 48-, and 60-month follow-ups. Post -RT QOL scores were baseline corrected and standardized to a [0-100] scale using EPIC-26 methodology. Correlations between QOL scores and dosimetric parameters were investigated, and the overall QOL differences between the two groups (QOLMargin-reduced -QOLcontrol ) were calculated.

RESULTS

The median QOL follow-up length for the 20 patients was 48 months. Difference between delivered dose and planned dose did not reach statistical significance (p > 0.1) for both targets and organs at risk between the two groups. At 4 years post-RT, standardized mean QOLMargin-reduced -QOLcontrol were improved for Urinary Incontinence, Urinary Irritative/Obstructive, Bowel, and Sexual EPIC domains by 3.5, 14.8, 10.2, and 16.1, respectively (higher values better). The control group showed larger PTV/rectum and PTV/bladder intersection volumes (7.2 ± 5.8, 18.2 ± 8.1 cc) than the margin-reduced group (2.6 ± 1.8, 12.5 ± 8.3 cc), though the dose to these intersection volumes did not reach statistical significance (p > 0.1) between the groups. PTV/rectum intersection volume showed a moderate correlation (r = -0.56, p < 0.05) to Bowel EPIC domain.

CONCLUSIONS

Results of this prospective study showed that margin-reduced group exhibited clinically meaningful improvement of QOL without compromising the target dose coverage.

Recurrence Risk Stratification for Women With FIGO Stage I Uterine Endometrioid Carcinoma Who Underwent Surgical Lymph Node Evaluation

OBJECTIVE

The aim of this study was to estimate the recurrence risk based on the number of prognostic factors for patients with stage I uterine endometrioid carcinoma (EC) who underwent surgical lymph node evaluation (SLNE) and were managed with observation.

METHODS

We queried our database for women with FIGO-2009 stage I EC who underwent surgical staging including SLNE. Multivariate analysis with stepwise model selection was used to determine independent risk factors for 5-year recurrence-free survival (RFS). Study groups based on risk factors were compared for RFS, disease-specific survival, and overall survival.

RESULTS

A total of 706 patients were identified: median age was 60 years (range, 30 to 93 y) and median follow-up was 120 months. Median number of examined lymph nodes was 8 (range, 1 to 66). 91% were stage IA, 75% had grade 1 and lymphovascular space invasion was detected in 6%. Independent predictors of 5-year RFS included age 60 years and above ( P =0.038), grade 2 ( P =0.003), and grade 3 ( P <0.001) versus grade 1. Five-year RFS for group 0 (age less than 60 y and grade 1) was 98% versus 92% for group 1 (either: age 60 y and older or grade 2/3) versus 84% for group 2 (both: age 60 y and above and grade 2/3), respectively ( P <0.001). Five-year disease-specific survival was 100% versus 98% versus 95%, ( P =0.012) and 5-year overall survival was 98% versus 90% versus 81%, for groups 0, 1, and 2, respectively ( P <0.001).

CONCLUSIONS

In patients with stage I EC who received SLNE and no adjuvant therapy, only age 60 years and above and high tumor grade were independent predictors of recurrence and can be used to quantify individualized recurrence risk, whereas lymphovascular space invasion was not an independent prognostic factor in this cohort.

The Prognostic Significance of the Depth of Cervical Stromal Invasion in Women With FIGO Stage II Uterine Endometrioid Carcinoma

OBJECTIVE

The objective of this study was to investigate the prognostic significance of the depth of cervical stromal invasion (CSI) in women with FIGO stage II uterine endometrioid adenocarcinoma (EC).

METHODS

Our database of women with EC was quired for patients with stage II EC. Pathologic slides were retrieved and reviewed by gynecologic pathologists to determine cervical stromal thickness and depth of CSI as a percentage of stromal thickness (%CSI). Kaplan-Meier, univariate, and multivariate analyses were used to compare recurrence-free, disease-specific (DSS), and overall survival (OS) between women who had<50% versus ≥50% CSI. Univariate and multivariate analyses were used to assess other prognostic variables associated with survival endpoints.

RESULTS

A total of 117 patients were included in our study who had hysterectomy between 1/1990 and 8/2021. Seventy-nine patients (68%) with <50% and 38 (32w%) with ≥50% CSI. After a median follow-up of 131 months, 5-year DSS was significantly worse for women with ≥50% CSI (78% vs. 91%; P =0.04). However, %CSI was not an independent predictor for any of the studied survival endpoints. Independent predictors of worse 5-year recurrence-free survival and DSS included FIGO grade 3 tumors ( P =0.02) and the presence of lymphovascular space invasion ( P =0.03). Grade 3 tumors were the only independent predictor of worse 5-year OS ( P =0.02).

CONCLUSIONS

Our results suggest that deep CSI is not an independent prognostic factor for survival endpoints in women with stage II uterine endometroid adenocarcinoma. The lack of independent prognostic significance of the depth CSI needs to be validated in a multi-institutional analysis.

The Prognostic Impact of Substantial Lymphovascular Space Invasion in Women with FIGO Stage I Uterine Endometrioid Carcinoma with Pathologically Negative Nodal Evaluation

PURPOSE/OBJECTIVE(S)

Substantiallymphovascular space invasion (LVSI) is an important predictor of lymph node involvement in women with endometrial carcinoma. However, its prognostic significance in women with stage I who had pathologic negative nodal evaluation (PNNE) was not fully evaluated. We aimed to evaluate the prognostic significance of substantial LVSI on recurrence-free (RFS), disease-specific (DSS) and overall survival (OS) in women with FIGO stage I uterine endometrioid adenocarcinoma (EC).

MATERIALS/METHODS

Our uterine cancer database was queried for women with stage I EC who had a hysterectomy and PNNE at our institution between 1/1990 and 11/2022. Postoperatively, patients were managed with observation or adjuvant radiation therapy (RT) with pelvic external beam RT or vaginal cuff brachytherapy (VB). Women with synchronous malignancies and those who received adjuvant chemotherapy were excluded. Pathologic specimens were retrieved and LVSI was quantified by Gynecology pathologists (none, focal or substantial). Patients' demographics, surgical and pathologic variables were analyzed. Predictors of RFS, DSS and OS using univariate (UVA) and multivariate analysis (MVA) were studied.

RESULTS

One thousand fifty-two patients were identified with a median age of 63 years and median follow-up of 9.7 years. Median number of examined lymph node (LN) were 9 (range 4-18). 907 patients (86.2%) had no LVSI, 87 (8.3%) had focal and 58 (5.5%) had substantial LVSI. In patients with focal LVSI, 32.2% received pelvic RT and 39.1% received VB. In patients with substantial LVSI, 20.7% received pelvic RT and 58.6% received VB.Recurrence was diagnosed in 86 patients (8.2%). While any LVSI was associated with tumor recurrence, there was no significant difference for the site of initial recurrence between patients with focal vs. substantial LVSI. 5-year RFS was 93.3% (95% CI 91.5-95.1), 76.8% (67.2-87.7) and 79.1% (67.6-95.3) for no, focal and substantial LVSI. The 5-year DSS was 97.6% (96.5-98.7), 83.5% (75-93.1), and 90% (81.8-99.9); and 5-year OS was 90.7% (88.7-92.8), 72.8% (62.9-84.2) and 86% (76.2-97.2), respectively. Independent predictors of worse 5-year RFS and DSS include any LVSI, age > 60 years, higher tumor grade. Independent predictors of worse 5- year OS include any LVSI, age > 60, high comorbidity burden, and higher tumor grade.

CONCLUSION

Our large data suggest similar recurrence-free, disease specific and OS for women with stage I uterine endometrioid carcinoma who had pathologically negative nodal evaluation and substantial or focal LVSI. There was no significant difference for the site of initial recurrence between patients with focal or substantial LVSI. Multi-institutional pooled analyses may be needed to validate our results.

Does Stereotactic Online Adaptive MRgRT to the Prostate Preclude the Need for Rectal Spacer

PURPOSE/OBJECTIVE(S)

Historical prospective trials have shown that hydrogel rectal spacers can be very effective at decreasing rectal wall dose, and in turn rectal toxicity, in patients undergoing curative intent fractionated courses of radiotherapy for prostate cancer. However, in the modern era of stereotactic online adaptive MR guided radiation (MRgRT), it's not yet determined if rectal spacers improve the potential daily need for plan adaptation.

MATERIALS/METHODS

A prospective database of MRgRT patients were queried for intact prostate cancer patients who received stereotactic online adaptive MR guided radiation. Patients were reviewed for the presence of a hydrogel rectal spacer present on the planning images. The number of adaptive fractions as well as the organs at risk out of tolerance were noted for each patient. Comparisons between number of fractions adapted as well as the number of fractions adapted for rectal constraints, were noted. For each case within this patient group that required plan adaptation, pre-specified dose constraints were finally met prior to treatment delivery.

RESULTS

A total of 27 patients were treated with stereotactic online adaptive MRgRT from 2020 to 2022. 8 patients had a hydrogel rectal spacer placed prior to treatment. Out of the 95 fractions delivered to non-hydrogel patients, 78 were adapted, with 52 for urethra, 31 for bladder, 5 for bladder neck, and 35 for rectum. Of the 40 fractions delivered to patients with a hydrogel spacer, 20 were adapted. The corresponding reasons for adaptation in this group were 14 times for the urethra, 19 times for the bladder, 8 times for the bladder neck, and 8 times for the rectum. It was common for multiple at-risk organs to require adaptation for a single fraction within both cohorts. Although the percentage of patients requiring adaptation for rectal constraints was greater in the non-hydrogel patients (36.8% vs. 20%), this was not found to be statistically significant; p value greater than 0.1.

CONCLUSION

The presence of a rectal spacer did not significantly reduce the need for online plan adaptation of the rectum for stereotactic online adaptive MRgRT. Furthermore, patients with a rectal spacer continued to often require adaptation to meet other prescription constraints. Further work is necessary to better select patients who would benefit from hydrogel spacers in the setting of online adaptive MRgRT. Additionally, longer follow-up of this patient population coupled with a larger patient cohort overall remains needed to increase the power of this analysis and to further explore the clinical outcomes of this patient group.

Does a Dominant Intraprostatic Lesion Boost Require Daily Adaptation when Treated with Stereotactic Online Adaptive MR-Guided Therapy?

PURPOSE/OBJECTIVE(S)

Multiple trials have demonstrated a dose-response relationship for radiation therapy in the treatment of localized prostate cancer. Recent data has also demonstrated a benefit with whole gland stereotactic radiation therapy (SBRT) in conjunction with a simultaneous integrated boost to the dominant intraprostatic lesion (DIL). SBRT with a DIL boost can often increase dose to nearby organs at risk such as the rectum and online adaptive MR guided radiation therapy (MGgRT) may offer a dosimetric and toxicity benefit.

MATERIALS/METHODS

A prospective database of MRgRT patients was queried for intact prostate cancer patients who received SBRT with a SIB to the DIL. The guideline for adaptation for coverage was to ensure the PTV-prostate coverage at 95% of prescribed dose was greater than 92% or by discretion of the treating physician. Adaptions for organs at risk were made to meet prescription constraints. The number of fractions requiring adaptation to meet organs at risk constraints and/or adequate coverage were reviewed.

RESULTS

A total of 26 patients were treated with SBRT with a DIL boost using stereotactic online adaptive MRgRT from 2020 to 2022. 10 of 26 patients were treated for re-irradiation of intact prostate. Out of the 130 fractions delivered, 107 fractions required adaptation (82.3%). 59 fractions were adapted for urethra (45.2%), 48 fractions were adapted for bladder (36.9%), 36 fractions were adapted for rectum (27.7%), 23 fractions were adapted for bladder neck (17.7%), and 19 fractions were adapted for coverage (14.6%). For 53 fractions (40.8 %), adaptation was required for more than one organ at risk.

CONCLUSION

A total of 82.3% of fractions required adaptation for patients treated with SBRT with a DIL boost using stereotactic online adaptive MRgRT. Adaptation occurred most frequently for urethral (45.2%), bladder (36.9%), and rectal constraints (27.7%). Further studies are needed to elucidate if daily adaptive online MRgRT translates to reduced patient toxicity and improved quality of life.

Dose-Escalated Radiation Alone or in Combination With Short-Term Total Androgen Suppression for Intermediate-Risk Prostate Cancer: Patient-Reported Outcomes From NRG/Radiation Therapy Oncology Group 0815 Randomized Trial

PURPOSE

To report patient-reported outcomes (PROs) of a phase III trial evaluating total androgen suppression (TAS) combined with dose-escalated radiation therapy (RT) for patients with intermediate-risk prostate cancer.

METHODS

Patients with intermediate-risk prostate cancer were randomly assigned to dose-escalated RT alone (arm 1) or RT plus TAS (arm 2) consisting of luteinizing hormone-releasing hormone agonist/antagonist with oral antiandrogen for 6 months. The primary PRO was the validated Expanded Prostate Cancer Index Composite (EPIC-50). Secondary PROs included Patient-Reported Outcome Measurement Information System (PROMIS)-fatigue and EuroQOL five-dimensions scale questionnaire (EQ-5D). PRO change scores, calculated for each patient as the follow-up score minus baseline score (at the end of RT and at 6, 12, and 60 months), were compared between treatment arms using a two-sample t test. An effect size of 0.50 standard deviation was considered clinically meaningful.

RESULTS

For the primary PRO instrument (EPIC), the completion rates were ≥86% through the first year of follow-up and 70%-75% at 5 years. For the EPIC hormonal and sexual domains, there were clinically meaningful (P < .0001) deficits in the RT + TAS arm. However, there were no clinically meaningful differences by 1 year between arms. There were also no clinically meaningful differences at any time points between arms for PROMIS-fatigue, EQ-5D, and EPIC bowel/urinary scores.

CONCLUSION

Compared with dose-escalated RT alone, adding TAS demonstrated clinically meaningful declines only in EPIC hormonal and sexual domains. However, even these PRO differences were transient, and there were no clinically meaningful differences between arms by 1 year.

The Impact of Racial Disparities on Outcome in Patients With Stage IIIC Endometrial Carcinoma: A Pooled Data Analysis

OBJECTIVE

To report the impact of race on clinical outcomes in patients with stage IIIC endometrial carcinoma.

MATERIALS AND METHODS

A retrospective multi-institutional study included 90 black and 568 non-black patients with stage IIIC endometrial carcinoma who received adjuvant chemotherapy and radiation treatments. Overall survival (OS) and recurrence-free survival (RFS) were calculated by the Kaplan-Meier method. Propensity score matching (PSM) was conducted. Statistical analyses were conducted using SPSS version 27.

RESULTS

The Median follow-up was 45.3 months. black patients were significantly older, had more nonendometrioid histology, grade 3 tumors, and were more likely to have >1 positive paraaortic lymph nodes compared with non-black patients (all P <0.0001). The 5-year estimated OS and RFS rates were 45% and 47% compared with 77% and 68% for black patients versus non-black patients, respectively ( P <0.001). After PSM, the 2 groups were well-balanced for all prognostic covariates. The estimated hazard ratios of black versus non-black patients were 1.613 ( P value=0.045) for OS and 1.487 ( P value=0.116) for RFS. After PSM, black patients were more likely to receive the "Sandwich" approach and concurrent chemoradiotherapy compared with non-black ( P =0.013) patients.

CONCLUSIONS

Black patients have higher rates of nonendometrioid histology, grade 3 tumors, and number of involved paraaortic lymph nodes, worse OS, and RFS, and were more likely to receive the "Sandwich" approach compared with non-black patients. After PSM, black patients had worse OS with a nonsignificant trend in RFS. Access to care, equitable inclusion on randomized trials, and identification of genomic differences are warranted to help mitigate disparities.

Does Prophylactic Paraortic Lymph Node Irradiation Improve Outcomes in Women With Stage IIIC1 Endometrial Carcinoma?

PURPOSE

To evaluate the impact of prophylactic paraortic lymph node (PALN) radiation therapy (RT) on clinical outcomes in patients with International Federation of Obstetrics and Gynecology 2018 stage IIIC1 endometrial cancer (EC).

METHODS AND MATERIALS

A multi-institutional retrospective study included patients with International Federation of Obstetrics and Gynecology 2018 stage IIIC1 EC lymph node assessment, status postsurgical staging, followed by adjuvant chemotherapy and RT using various sequencing regimens. Overall survival (OS) and recurrence-free survival (RFS) rates were estimated by the Kaplan-Meier method. Univariable and multivariable analysis were performed by Cox proportional hazard models for RFS/OS. In addition, propensity score matching was used to estimate the effect of the radiation field extent on survival outcomes.

RESULTS

A total of 378 patients were included, with a median follow-up of 45.8 months. Pelvic RT was delivered to 286 patients, and 92 patients received pelvic and PALN RT. The estimated OS and RFS rates at 5 years for the entire cohort were 80% and 69%, respectively. There was no difference in the 5-year OS (77% vs 87%, P = .47) and RFS rates (67% vs 70%, P = .78) between patients treated with pelvic RT and those treated with pelvic and prophylactic PALN RT, respectively. After propensity score matching, the estimated hazard ratios (HRs) of prophylactic PALN RT versus pelvic RT were 1.50 (95% confidence interval, 0.71-3.19; P = .28) for OS and 1.24 (95% confidence interval, 0.64-2.42; P = .51) for RFS, suggesting that prophylactic PALN RT does not improve survival outcomes. Distant recurrence was the most common site of first recurrence, and the extent of RT field was not associated with the site of first recurrence (P = .79).

CONCLUSIONS

Prophylactic PALN RT was not significantly associated with improved survival outcomes in stage IIIC1 EC. Distant metastasis remains the most common site of failure despite routine use of systemic chemotherapy. New therapeutic approaches are necessary to optimize the outcomes for women with stage IIIC1 EC.

Quantification of recurrence risk based on number of adverse prognostic factors in women with stage I uterine endometrioid carcinoma

Objective

The goal was to develop an updated model to predict the risk of recurrence, based on the number of adverse pathologic features in women with International Federation of Gynecology and Obstetrics stage I uterine endometrioid carcinoma, who did not undergo any adjuvant treatment.

Material and Methods

Women at a single center who underwent surgical staging without adjuvant therapy between January 1990 and December 2019 were included. Cox proportional hazards model was used to identify independent predictors of relapse free survival (RFS). Prognostic groups were then created based on the number of independent predictors of recurrence that were identified (0, 1, or 2-3 risk factors). Overall survival (OS) and disease specific survival (DSS) were also calculated for each group.

Results

In total 1133 women were eligible for inclusion. Median follow-up was 84 months. Independent prognostic factors of recurrence included: age ≥60; grade 2 or 3 differentiation; and presence of lymphovascular space invasion (LVSI). Due to the small number of patients with either 2 or 3 risk factors, these groups were combined into one (group 2/3). Isolated vaginal cuff recurrence was the most common site of recurrence in all study groups (2%, 7%, and 17% for groups 0, 1, and 2/3, respectively). Five-year RFS rates were 96%, 85%, and 57% for groups 0, 1, and 2/3 (p<0.01), respectively. Five-year DSS rates were 99%, 96%, and 85% and 5-year OS rates were 94%, 85%, and 62% (p<0.01), respectively.

Conclusion

We identified older age, high grade, and presence of LVSI as independent predictors of recurrence for women with stage I uterine endometrioid carcinoma. Using these prognostic factors, recurrence risk can be quantified for individual patients, and these factors can be used in deciding the appropriate adjuvant management course.

Matched-pair Analysis for Survival Endpoints Between Women With Early-stage Uterine Carcinosarcoma and Uterine Serous Carcinoma

OBJECTIVE

The objective of this study was to compare survival endpoints between women with uterine carcinosarcoma and those with uterine serous carcinoma utilizing matching analysis.

METHODS

Patients with stages I to II who underwent hysterectomy at our institution were included in this analysis. Patients with carcinosarcoma were then matched to patients with serous carcinoma based on stage, and adjuvant management received (observation, radiation treatment alone, chemotherapy alone, or combined modality with radiotherapy and chemotherapy. Recurrence-free survival, disease-specific survival, and overall survival were calculated for the 2 groups.

RESULTS

A total of 134 women were included (67 women with carcinosarcoma and 67 with serous carcinoma, matched 1:1). There was no statistically significant difference between the 2 groups regarding 5-year recurrence-free survival (59% vs. 62%), disease-specific survival (66% vs. 67%), or overall survival (53% vs. 57%), respectively. The only independent predictor of shorter recurrence-free survival for the entire cohort was the lack of adjuvant combined modality therapy, while lower uterine segment involvement was the only independent predictor for shorter disease-specific survival. Lack of lymph node dissection and lack of adjuvant combined modality therapy were independent predictors of shorter overall survival.

DISCUSSION

When matched based on stage and adjuvant treatment, our study suggests that there is no statistically significant difference in survival endpoints between women with early-stage carcinosarcoma and serous carcinoma. Adjuvant combined modality treatment is an independent predictor of longer recurrence-free survival and overall survival.

The impact of race, comorbid conditions and obesity on survival endpoints in women with high grade endometrial carcinoma

OBJECTIVE

To estimate overall survival, disease-specific survival, and progression-free survival among high grade endometrial carcinoma cases and to determine factors impacting survival for non-Hispanic white and non-Hispanic black women.

METHODS

We identified high grade endometrial carcinoma cases among non-Hispanic white and non-Hispanic black women from ongoing institutional studies, and determined eligibility through medical record and pathologic review. We estimated effects of demographic and clinical variables on survival outcomes using Kaplan Meier methods and Cox proportional hazards modelling.

RESULTS

Non-Hispanic Black women with BMI <25.0 had poorest overall survival compared to non-Hispanic white women with BMI <25.0 (HR 3.03; 95% CI [1.35, 6.81]), followed by non-Hispanic black women with BMI 25.0+ (HR 2.43; 95% CI [1.28, 4.60]). A similar pattern emerged for disease-specific survival. Non-Hispanic black women also had poorer progression-free survival than non-Hispanic white women (HR 1.40; 95% CI [1.01, 1.93]). Other significant factors impacting survival outcomes included receipt of National Cancer Center Network (NCCN) guideline-concordant treatment (GCT), earlier stage at diagnosis, and fewer comorbid conditions.

CONCLUSIONS

BMI and race interact and modify the association with high grade endometrial carcinoma survival. Other potentially modifiable factors, such as reducing comorbidities and increasing access to GCT will potentially improve survival after diagnosis of high grade endometrial carcinomas. A better understanding of the molecular drivers of these high grade carcinomas may lead to targeted therapies that reduce morbidity and mortality associated with these aggressive tumors.

The Impact of Adjuvant Management Strategies on Outcomes in Women With Early Stage Uterine Serous Carcinoma

Objective To determine the impact of different adjuvant strategies on outcomes in women with early-stage uterine serous carcinoma (USC). Methods Our retrospective database for women with endometrial carcinoma was queried for women with 2009 International Federation of Gynecology and Obstetrics (FIGO) stages I-II USC who underwent surgical staging between January 1991 and April 2019 followed by adjuvant management (observation, radiation therapy (RT), chemotherapy (CT), or combined modality treatment (CRT)). Chi-square tests were performed to compare differences in outcome by type of adjuvant management. Recurrence-free survival (RFS), disease-specific survival (DSS), and overall survival (OS) were assessed by Kaplan-Meier and log-rank tests. Univariate and multivariate analyses (MVA) were performed to identify statistically significant predictors of survival endpoints. Results We identified 171 women who met our inclusion criteria. The median follow-up time was 70.5 months. Seventy-five percent of the study cohort was FIGO stage IA, 13% were stage IB, and 12% were stage II. All women underwent pelvic lymph node dissection with a median number of dissected lymph nodes of 14. Omentectomy was performed in 64% of patients. Adjuvant RT was utilized in 56% of women (65 patients received vaginal brachytherapy alone, 10 patients received pelvic RT, and 21 patients received a combination of both). The most commonly used chemotherapy regimen was carboplatin and paclitaxel with a median number of cycles of six. A total of 44% of the cohort received CRT, 12% received RT alone, 19% received chemo alone, and 25% were observed. Five-year RFS was 73% for those who received CRT, 84% for those who received RT alone, 68% for those who received CT alone, and 55% for those who were observed (p=0.13). Five-year DSS was 81%, 94%, 71%, and 60%, respectively (p=0.02). Five-year OS was 76%, 70%, 60%, and 56%, respectively (p=0.11). On MVA of OS and DSS, a higher percentage of myometrial invasion, the presence of lower uterine segment involvement, positive peritoneal cytology, and receipt of chemotherapy alone/observation were independent predictors of worse outcomes. The sole independent predictor of worse RFS on MVA was the presence of positive peritoneal cytology. Conclusion In this cohort of women with early-stage USC who underwent surgical staging, adjuvant radiation treatment with or without chemotherapy was associated with improved survival endpoints and trended toward improved recurrence rates.

Volumetric-Modulated Arc Radiotherapy with Daily Image-Guidance Carries Better Toxicity Profile for Higher Risk Prostate Cancer

PURPOSE

To compare radiotherapy-induced toxicity for localized prostate-cancer (PCa) treated with versus without daily image-guidance.

PATIENTS AND METHODS

We identified consecutive intermediate and high-risk localized PCa patients treated with definitive radiotherapy using intensity-modulated radiotherapy (IMRT) with variable duration of androgen-deprivation therapy (ADT) within 2015-2016 (Arm-A) and 2005-2007 (Arm-B). Arm-A cases received daily online imaging guidance (IGRT) using cone-beam computed tomography (CBCT) unlike Arm-B candidates with no daily IGRT. After reporting demographic, clinico-pathological features and treatment details, we compared acute (within 3 months post-therapy) and late RT-induced toxicities between study groups graded by RTOG/CTCAE criteria. Uni/multivariate analyses (UVA/MVA) were performed to identify independent predictors for RT-related side-effects.

RESULTS

We were able to identify 257 cases who met our inclusion criteria. Overall, median age was 73 years (48-85), 67% had intermediate-risk and 47% received ADT. Arm-A included 72 patients who received IMRT delivered using volumetric-modulated arc therapy (VMAT), whereas, Arm-B was formed of 185 cases who utilized step-and-shoot static IMRT. Clinico-pathological features and treatment details were non-different across study arms except that Arm-A had more Grade Group 3, higher median total dose (79.2 vs. 74 Gy) and more pelvic lymph-nodes RT (p <0.05). Although acute toxicity was similar across groups, Arm-B encountered higher late toxicity score, more intense late genitourinary side-effects (P=0.008), with non-different late lower-gastrointestinal toxicities. On MVA, lack of daily CBCT, African-American race and higher comorbidities were independently predictive for late toxicities.  Conclusion: IMRT with daily CBCT permitted safe delivery of dose-escalated IMRT with improved toxicity profile for higher-risk prostate cancer.

Abstract S09-02: Outcomes by race for cancer patients hospitalized with SARS-CoV-2 infection

Purpose: Disparities in COVID-19 outcomes have been widely reported, with disproportionate negative impacts on the African American (AA) population. The purpose of this study was to evaluate the impact of race on COVID-19 outcomes for cancer patients hospitalized in a large Michigan health care system.

Methods: A cohort of hospitalized, laboratory-confirmed SARS-CoV-2 positive patients was identified through the Henry Ford Health System Institutional COVID prospective patient registry between March 1st–May 2020. Those with a diagnosis of cancer were identified using our institutional tumor registry and electronic health record (EHR). Patient self-reported race/ethnicity data were extracted from the system’s centralized EHR, as were other demographic and clinical covariates. Racial differences in cumulative incidence of mortality and hospital discharge were tested. To further evaluate the effect of race on the mortality, Fine-Gray competing-risks model was performed with discharge alive as a competing event. A P&lt;0.05 was considered statistically significant.

Results: Out of the 204 COVID+ cancer patients hospitalized in our health care system, 69.6% were AA (N=142). AA patients were slightly younger than non-AA patients (70.35 v. 74.58, p=0.023). No difference in mean BMI was detected (30.33 AA v. 29.87 non-AA, p = 0.68). A smaller proportion of AA patients had active cancer (36.6% v. 40.3%, p = 0.73). Outcomes were generally inferior in the AA cohort, although these differences were not statistically significant. The rate of ICU admission was 41.5% in AA and 37.1% in non-AA (p=0.659). 34.5% of AA patients required intubation compared to 25.8% of non-AA patients (p=0.288). In our model, older age was the only variable that significantly increased the risk of death (standard hazard ratio SHR 1.05, p = 0.002). The risk of death was higher for AA patients (SHR 1.92, p=0.068) and males (SHR 1.62, p = 0.078) but did not meet statistical significance.

Discussion: COVID-19 outcomes were worse in the AA cancer population, but these differences did not meet statistical significance. Inferior outcomes for AA cancer patients were seen despite younger age and a smaller proportion of patients with active cancer. Our analysis focused on hospitalized patients, which would tend to select patients with similar disease severity. Notably, AA patients were significantly over-represented in our cohort (70% of hospitalizations compared to 14% of Michigan population). Our results suggest that racial disparities in outcomes for cancer patients with a SARS-CoV-2 infection may exist, but further study of larger, less selected populations is needed.

Citation Format: Steven S. Chang, Clara Hwang, Mohamed A. Elshaikh, Amy Tang, Christine M. Neslund-Dudas, Albert M. Levin, Laila M. Poisson, Benjamin A. Rybicki. Outcomes by race for cancer patients hospitalized with SARS-CoV-2 infection [abstract]. In: Proceedings of the AACR Virtual Meeting: COVID-19 and Cancer; 2020 Jul 20-22. Philadelphia (PA): AACR; Clin Cancer Res 2020;26(18_Suppl):Abstract nr S09-02.

A deep dive into understanding tumor foci classification using multiparametric MRI based on convolutional neural network

PURPOSE

Deep learning models have had a great success in disease classifications using large data pools of skin cancer images or lung X-rays. However, data scarcity has been the roadblock of applying deep learning models directly on prostate multiparametric MRI (mpMRI). Although model interpretation has been heavily studied for natural images for the past few years, there has been a lack of interpretation of deep learning models trained on medical images. In this paper, an efficient convolutional neural network (CNN) was developed and the model interpretation at various convolutional layers was systematically analyzed to improve the understanding of how CNN interprets multimodality medical images and the predictive powers of features at each layer. The problem of small sample size was addressed by feeding the intermediate features into a traditional classification algorithm known as weighted extreme learning machine (wELM), with imbalanced distribution among output categories taken into consideration.

METHODS

The training data collection used a retrospective set of prostate MR studies, from SPIE-AAPM-NCI PROSTATEx Challenges held in 2017. Three hundred twenty biopsy samples of lesions from 201 prostate cancer patients were diagnosed and identified as clinically significant (malignant) or not significant (benign). All studies included T2-weighted (T2W), proton density-weighted (PD-W), dynamic contrast enhanced (DCE) and diffusion-weighted (DW) imaging. After registration and lesion-based normalization, a CNN with four convolutional layers were developed and trained on tenfold cross validation. The features from intermediate layers were then extracted as input to wELM to test the discriminative power of each individual layer. The best performing model from the tenfolds was chosen to be tested on the holdout cohort from two sources. Feature maps after each convolutional layer were then visualized to monitor the trend, as the layer propagated. Scatter plotting was used to visualize the transformation of data distribution. Finally, a class activation map was generated to highlight the region of interest based on the model perspective.

RESULTS

Experimental trials indicated that the best input for CNN was a modality combination of T2W, apparent diffusion coefficient (ADC) and DWI_b50 . The convolutional features from CNN paired with a weighted extreme learning classifier showed substantial performance compared to a CNN end-to-end training model. The feature map visualization reveals similar findings on natural images where lower layers tend to learn lower level features such as edges, intensity changes, etc, while higher layers learn more abstract and task-related concept such as the lesion region. The generated saliency map revealed that the model was able to focus on the region of interest where the lesion resided and filter out background information, including prostate boundary, rectum, etc. CONCLUSIONS: This work designs a customized workflow for the small and imbalanced dataset of prostate mpMRI where features were extracted from a deep learning model and then analyzed by a traditional machine learning classifier. In addition, this work contributes to revealing how deep learning models interpret mpMRI for prostate cancer patient stratification.

Executive summary of the American Radium Society® Appropriate Use Criteria for management of uterine carcinosarcoma

OBJECTIVE

Uterine carcinosarcomas (UCS) represent a rare but aggressive subset of endometrial cancers, comprising <5% of uterine malignancies. To date, limited prospective trials exist from which evidence-based management of this rare malignancy can be developed.

METHODS

The American Radium Society Appropriate Use Criteria presented in this manuscript are evidence-based guidelines developed by a multidisciplinary expert panel for management of women with UCS. An extensive analysis of current medical literature from peer-reviewed journals was performed. A well-established methodology (modified Delphi) was used to rate the appropriate use of imaging and treatment procedures for the management of UCS. These guidelines are intended for the use of all practitioners who desire information about the management of UCS.

RESULTS

The majority of patients with UCS will present with advanced extra uterine disease, with 10% presenting with metastatic disease. They have worse survival outcomes when compared to uterine high-grade endometrioid adenocarcinomas. The primary treatment for non-metastatic UCS is complete surgical staging with total hysterectomy, salpingo-oophorectomy and lymph node staging. Patients with UCS appear to benefit from adjuvant multimodality therapy to reduce the chance of tumor recurrence with the potential to improve overall survival.

CONCLUSION

Women diagnosed with uterine UCS should undergo complete surgical staging. Adjuvant multimodality therapies should be considered in the treatment of both early- and advanced stage patients. Long-term surveillance is indicated as many of these women may recur. Prospective clinical studies of women with UCS are necessary for optimal management.

Charlson Comorbidity score influence on prostate cancer survival and radiation-related toxicity

INTRODUCTION

In addition to survival endpoints, we explored the impact of Charlson Comorbidity-Index (CCI) on the acute and late toxicities in men with localized prostate cancer who received dose-escalated definitive radiotherapy (RT).

MATERIALS AND METHODS

CCI scores at diagnosis and survival outcomes were identified for men with intermediate/high-risk prostate cancer treated with RT (1/2007-12/2012). Study-cohort was accordingly grouped into no, mild and severe comorbidity (CCI-0, 1 or 2+). CCI-groups were compared for demographics, prognostic-factors; and RT-related toxicities based on RTOG/CTCAE criteria. Kaplan-Meier curves and Uni/multivariate (MVA) analyses were used to examine the influence of CCI-group on overall (OS), disease-specific (DSS) and biochemical-relapse free (BRFS) survival.

RESULTS

We included 257 patients with median age 73 years (48-85), 53% African-American and 67% had intermediate-risk. Median prostate RT-dose was 76 Gy; and 47% received androgen-deprivation therapy. CCI-0,1,2+ groups encompassed 76 (30%), 54 (21%) and 127 (49%) patients, respectively and were well-balanced. Ten and 15-years OS were significantly different (76% versus 46% versus 55% for 10-years OS and 53% versus 31% versus 14% for 15-years OS for CCI-0 versus CCI-1[HR:2.25; CI[1.31-3.87]] versus CCI-2+[HR:2.73; CI[1.73-4.31]]; p < 0.001. CCI-0 had better DSS than CCI-2+ (HR:2.23; CI[1.06-4.68]; p = 0.03) and BRFS was similar (p = 0.99). Late G2/3 RT-toxicities were more common in CCI-2+ (47%) than CCI-1 (44%) and CCI-0 (29%), p = 0.032; with non-different acute-toxicities (p = 0.62). On MVA, increased CCI was deterministic for OS (HR:3.65; CI [1.71:7.79]; p < 0.001) and was only marginal for DSS (HR:2.55; CI [0.98-6.6]; p = 0.05) with no impact on BRFS (p > 0.05).

CONCLUSIONS

Higher CCI is a significant predictor for late RT-related side-effects and shorter OS in men with localized prostate cancer. Baseline comorbidities should be considered during initial counseling and follow up visits.

Geometric and dosimetric impact of anatomical changes for MR-only radiation therapy for the prostate

PURPOSE

With the move towards magnetic resonance imaging (MRI) as a primary treatment planning modality option for men with prostate cancer, it becomes critical to quantify the potential uncertainties introduced for MR-only planning. This work characterized geometric and dosimetric intra-fractional changes between the prostate, seminal vesicles (SVs), and organs at risk (OARs) in response to bladder filling conditions.

MATERIALS AND METHODS

T2-weighted and mDixon sequences (3-4 time points/subject, at 1, 1.5 and 3.0 T with totally 34 evaluable time points) were acquired in nine subjects using a fixed bladder filling protocol (bladder void, 20 oz water consumed pre-imaging, 10 oz mid-session). Using mDixon images, Magnetic Resonance for Calculating Attenuation (MR-CAT) synthetic computed tomography (CT) images were generated by classifying voxels as muscle, adipose, spongy, and compact bone and by assignment of bulk Hounsfield Unit values. Organs including the prostate, SVs, bladder, and rectum were delineated on the T2 images at each time point by one physician. The displacement of the prostate and SVs was assessed based on the shift of the center of mass of the delineated organs from the reference state (fullest bladder). Changes in dose plans at different bladder states were assessed based on volumetric modulated arc radiotherapy (VMAT) plans generated for the reference state.

RESULTS

Bladder volume reduction of 70 ± 14% from the final to initial time point (relative to the final volume) was observed in the subject population. In the empty bladder condition, the dose delivered to 95% of the planning target volume (PTV) (D95%) reduced significantly for all cases (11.53 ± 6.00%) likely due to anterior shifts of prostate/SVs relative to full bladder conditions. D15% to the bladder increased consistently in all subjects (42.27 ± 40.52%). Changes in D15% to the rectum were patient-specific, ranging from -23.93% to 22.28% (-0.76 ± 15.30%).

CONCLUSIONS

Variations in the bladder and rectal volume can significantly dislocate the prostate and OARs, which can negatively impact the dose delivered to these organs. This warrants proper preparation of patients during treatment and imaging sessions, especially when imaging required longer scan times such as MR protocols.

Automatic Segmentation of the Prostate on CT Images Using Deep Neural Networks (DNN)

PURPOSE

Recent advances in deep neural networks (DNNs) have unlocked opportunities for their application for automatic image segmentation. We have evaluated a DNN-based algorithm for automatic segmentation of the prostate gland on a large cohort of patient images.

METHODS AND MATERIALS

Planning-CT data sets for 1114 patients with prostate cancer were retrospectively selected and divided into 2 groups. Group A contained 1104 data sets, with 1 physician-generated prostate gland contour for each data set. Among these image sets, 771 were used for training, 193 for validation, and 140 for testing. Group B contained 10 data sets, each including prostate contours delineated by 5 independent physicians and a consensus contour generated using the STAPLE method in the CERR software package. All images were resampled to a spatial resolution of 1 × 1 × 1.5 mm. A region (128 × 128 × 64 voxels) containing the prostate was selected to train a DNN. The best-performing model on the validation data sets was used to segment the prostate on all testing images. Results were compared between DNN and physician-generated contours using the Dice similarity coefficient, Hausdorff distances, regional contour distances, and center-of-mass distances.

RESULTS

The mean Dice similarity coefficients between DNN-based prostate segmentation and physician-generated contours for test data in Group A, Group B, and Group B-consensus were 0.85 ± 0.06 (range, 0.65-0.93), 0.85 ± 0.04 (range, 0.80-0.91), and 0.88 ± 0.03 (range, 0.82-0.92), respectively. The Hausdorff distance was 7.0 ± 3.5 mm, 7.3 ± 2.0 mm, and 6.3 ± 2.0 mm for Group A, Group B, and Group B-consensus, respectively. The mean center-of-mass distances for all 3 data set groups were within 5 mm.

CONCLUSIONS

A DNN-based algorithm was used to automatically segment the prostate for a large cohort of patients with prostate cancer. DNN-based prostate segmentations were compared to the consensus contour for a smaller group of patients; the agreement between DNN segmentations and consensus contour was similar to the agreement reported in a previous study. Clinical use of DNNs is promising, but further investigation is warranted.

The impact of Charlson Comorbidity Index on survival outcomes in men with prostate cancer who underwent definitive prostate radiotherapy

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Background: Life expectancy is very essential in deciding treatment options in men with prostate cancer (PCa); however, the impact of comorbidities on outcomes is not well-established. We investigated the influence of Charlson Comorbidity Index (CCI) on survival endpoints in men with localized PCa who were treated with prostate radiotherapy (RT). Methods: Men with intermediate and high risk PCa who were treated with definitive RT between 1/2007 and 12/2012 were included. Groups were created according to their baseline CCI score at diagnosis into no, mild and severe comorbidity (CCI 0, 1 or 2+). The groups were then compared based on patients’ characteristics and prognostic factors. Kaplan-Meier curves and Uni/multivariate analyses (MVA) were used to examine the impact of CCI groups on overall (OS), disease specific (DSS), and biochemical relapse free (BRFS) survival. Results: 257 patients were identified after excluding low risk, metastatic cases and those with inadequate follow up. Median follow-up was 92 months (range: 2-135) and median age was 73 years (range: 48-85). 53% of the cases were black and 67% were of intermediate risk. Median RT dose was 76 Gy and 47% received androgen deprivation therapy. CCI groups 0, 1 and 2+ encompassed 76 (30%), 54 (21%) and 127 (49%) patients, respectively. Groups were generally well-balanced. 10 and 15 years OS was significantly different across CCI groups (76% & 53%, 46% & 31% and 55% & 14%, for CCI-0, 1 and 2+ respectively; p < 0.001). CCI-0 had better DSS than CCI-2+ ( p = 0.03) with no difference for CCI-0 vs 1 ( p = 0.1). BRFS was non-different among CCI groups ( p = 0.99). On MVA, increased CCI was deterministic for OS ( p < 0.001) after adjusting for age, Gleason’s score and T-stage. For DSS, only age and T3 vs T1/2 were independently prognostic ( p < 0.001); whereas CCI-1 vs 0 was only marginal ( p = 0.05). Conclusions: Higher CCI was a significant predictor of shorter OS in intermediate and high-risk PCa. Baseline comorbidities should be taken into consideration during patient counselling for treatment options and in designing prospective trials for men with localized prostate cancer.

Disparities in the Use of Single-fraction Stereotactic Radiosurgery for the Treatment of Brain Metastases From Non-small Cell Lung Cancer

PURPOSE

Radiation treatment patterns in patients with brain metastases from non-small cell lung cancer (NSCLC) have not been well elucidated. The National Cancer Database (NCDB) was used to evaluate trends in the use of whole brain radiation therapy (WBRT) and stereotactic radiosurgery (SRS) for brain metastasis from NSCLC.

METHODS

This NCDB study included patients > 18 years old with metastatic NSCLC treated with single-fraction SRS or WBRT between 2004 and 2014. Chi-square, t-test, and multivariable logistic regression analyses were used to identify predictors of SRS versus WBRT.

RESULTS

Of 40,803 patients, 34,183 (83.8%) received WBRT and 6,620 (16.2%) received SRS. SRS utilization increased from 7% (157 cases) in 2004 to 37% (1,346 cases) in 2014 (p < .001). SRS was utilized more by academic than community facilities (22% versus 13%, p < .001). The strongest independent predictors of SRS included year of diagnosis in 2010-2014 versus 2004-2009 (odds ratio [OR] 2.62, 95% CI 2.46-2.79, p < .0001), metropolitan versus rural (OR 2.26, CI 1.79-2.85, p < .0001), distance from cancer-reporting facility of ≥ 30 versus < 30 miles (OR 2.36, CI 2.18-2.56, p < .0001), private insurance versus non-insured patients (OR 1.96, CI 1.68-2.29, p < .0001), and academic versus community facility (OR 1.76, CI 1.66-1.87, p < .0001).

CONCLUSION

SRS for NSCLC brain metastases has steadily increased in the United States; however, WBRT remains the most commonly used. Wide geographic and socioeconomic variations exist in the utilization of SRS and WBRT for this patient population.

Multiparametric MRI-based intraprostatic tumor volume delineation in localized prostate cancer

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Background: Multiparametric MR imaging (mpMRI) has shown promising results in the diagnosis and localization of prostate cancer. Furthermore, mpMRI may play an important role in identifying a suitable target volume for intraprostatic radiotherapy boost. We sought to investigate the level of correlation between dominant tumor foci contoured on various mpMRI sequences. Methods: mpMRI data from 18 patients with MR-guided biopsy-proven prostate cancer were obtained from the SPIE-AAPM-NCI Prostate MR Classification Challenge. Each case consisted of T2-weighted, apparent diffusion coefficient (ADC), and ktrans images computed from dynamic contrast-enhanced sequences. All image sets were rigidly co-registered, and the dominant tumor foci were identified and contoured for each MRI sequence. Hausdorff distance (HD), mean distance to agreement (MDA), and Dice and Jaccard coefficients were calculated between the contours for each pair of MRI sequences (i.e., T2 vs. ADC, T2 vs. ktrans, and ADC vs. ktrans). The Pearson correlation coefficient (PCC) was also obtained for Dice and Jaccard between these image pairs. Results: The dominant tumor foci were located in the peripheral zone, transition zone, and anterior fibromuscular stroma in 5 (28%), 7 (39%), and 6 (33%) patients, respectively. Mean tumor volumes in the T2-weighted, ADC, and ktrans sequences were 2.71 +/- 2.74 mL, 2.71 +/- 2.67 mL, and 2.21 +/- 1.86 mL, respectively. Mean HD and MDA were lowest (4.34 +/- 1.52 mm and 1.00 +/- 0.52 mm) and Dice and Jaccard coefficients highest (0.74 +/- 0.12 and 0.60 +/- 0.15) for T2 vs. ADC. The PCC for Dice was 0.15 between T2 vs. ADC and T2 vs. ktrans, 0.37 between T2 vs. ADC and ADC vs. ktrans, and 0.62 between T2 vs. ktrans and ADC vs. ktrans, and similar values were obtained for Jaccard (0.12, 0.32, and 0.67, respectively). Four patients were excluded in the PCC calculation as no vascular permeability was visible in the ktrans maps. Conclusions: This analysis suggests that T2-weighted and ADC sequences have high correlation in identifying a suitable intraprostatic radiotherapy boost volume for localized prostate cancer. Furthermore, ktrans maps may provide additional information for tumor volume delineation.

Impact of age at diagnosis on racial disparities in endometrial cancer patients

INTRODUCTION

Although black patients with endometrial cancer (EC) have worse survival compared with white patients, the interaction between age/race has not been examined. The primary objective was to evaluate the impact of age at diagnosis on racial disparities in disease presentation and outcome in EC.

METHODS

We evaluated women diagnosed with EC between 1991 and 2010 from the Surveillance, Epidemiology, and End Results. Mutation status for TP53 or PTEN, or with the aggressive integrative, transcript-based, or somatic copy number alteration-based molecular subtype were acquired from the Cancer Genome Atlas. Logistic regression model was used to estimate the interaction between age and race on histology. Cox regression model was used to estimate the interaction between age and race on survival.

RESULTS

78,184 white and 8518 black patients with EC were analyzed. Median age at diagnosis was 3-years younger for black vs. white patients with serous cancer and carcinosarcoma (P<0.0001). The increased presentation of non-endometrioid histology with age was larger in black vs. white patients (P<0.0001). The racial disparity in survival and cancer-related mortality was more prevalent in black vs. white patients, and in younger vs. older patients (P<0.0001). Mutations in TP53, PTEN and the three aggressive molecular subtypes each varied by race, age and histology.

CONCLUSIONS

Aggressive histology and molecular features were more common in black patients and older age, with greater impact of age on poor tumor characteristics in black vs. white patients. Racial disparities in outcome were larger in younger patients. Intervention at early ages may mitigate racial disparities in EC.

External pelvic and vaginal irradiation vs. vaginal irradiation alone as postoperative therapy in women with early stage uterine serous carcinoma: Results of a National Cancer Database analysis

PURPOSE

Adjuvant treatment in early stage uterine serous carcinoma (USC) usually consists of chemotherapy with vaginal brachytherapy (VB), pelvic external beam radiation therapy (EBRT), or combination. We compared survival outcomes across these various radiation treatment modalities using the National Cancer Database.

METHODS AND MATERIALS

The National Cancer Database was queried for adult females with histologically confirmed International Federation of Gynecology and Obstetrics 1988 Stage I-II USC diagnosed from 2003 to 2013 treated definitively with hysterectomy, adjuvant chemotherapy, and radiation therapy. χ² tests were used to assess differences by radiation type (VB, pelvic EBRT, and EBRT + VB) and various clinical variables. Kaplan-Meier and log-rank test methods were used to evaluate survival outcomes. Risk factors related to overall survival were identified by univariate and multivariate analysis.

RESULTS

We identified 1336 patients with USC who met our inclusion criteria. Most patients were treated with VB (66%) compared with EBRT (21%) or combination EBRT + VB (13%). The proportion of patients who received EBRT (including EBRT + VB) was higher for those who did not have a lymph node dissection or with fewer dissected lymph nodes. Patients treated with VB alone had longer 5-year survival rates (84% [95% confidence interval: 80, 90]) than those treated with EBRT (75% [95% confidence interval: 69, 80]) (p < 0.001). On multivariate analysis, the presence of lymphovascular space invasion (hazard ratio, 2.48; p < 0.001) and the absence of a lymph node dissection (hazard ratio, 2.24; p = 0.047) were independent predictors of overall survival.

CONCLUSIONS

This large hospital-based study suggests that VB alone may be sufficient for adjuvant radiation treatment in women with USC treated with adjuvant chemotherapy and who underwent an adequate surgical staging.

The impact of lymphadenectomy on survival endpoints in women with early stage uterine endometrioid carcinoma: A matched analysis

OBJECTIVES

The role of pelvic lymphadenectomy (LA) in women with stage I endometrial carcinoma (EC) is controversial. The objective of this study is to investigate the prognostic impact of LA on survival endpoints in matched cohorts of women with stage I EC solely of endometrioid histology. Survival endpoints included recurrence-free (RFS), disease-specific (DSS) and overall survival (OS).

METHODS AND MATERIALS

Patients with FIGO stage I EC who underwent hysterectomy with LA as part of their surgical staging between 1/1990 and 6/2015 were matched to a similar group that underwent hysterectomy without lymphadenectomy (NLA), based on stage, grade and adjuvant management. Univariate and multivariate modeling with Cox regression analysis was carried out for predictors of survival endpoints.

RESULTS

870 women constituted the study cohort (435 in each group). Median number of dissected lymph node in the LA group was 9 (range, 5-75). There was no statistically significant difference between the two groups in regards to 5-year OS (87.2% for LA vs. 91.7% for NLA) (p=0.36), DSS 97.7% vs. 98% (p=0.54) and RFS (93.7% vs. 90% (p=0.08), respectively. Lymphadenectomy was not a predictor of any of the studied survival endpoints. On multivariate analysis for the entire cohort, older age, deep myometrial invasion and higher tumor grade were predictors of worse RFS. For DSS, higher tumor grade, lower uterine segment (LUS) involvement and FIGO stage IB were significant predictors of worse outcome. For OS, older age and LUS involvement were the only two independent predictors for shorter OS.

CONCLUSIONS

After matching for FIGO stage, grade and adjuvant management, it appears that lymphadenectomy in women with stage I EC does not impact survival endpoints.

Revisiting Milan cervical cancer study: Do the original findings hold in the era of chemotherapy?

BACKGROUND

The primary treatment of early stage cervical carcinoma (IB-IIA) is either surgery or radiation therapy based on the pivotal Milan randomized study published twenty years ago. In the presence of high-risk features, the gold standard treatment is concurrent chemotherapy and radiation therapy (CRT) whether it is the in the postoperative or the definitive setting. Using the National Cancer Data Base (NCDB), the goal of our study is to compare the outcomes of surgery and radiation therapy in the chemotherapy era.

METHODS

Between 2004 and 2013, 5478 patients diagnosed with early stage cervical cancer were divided into 2 groups based on their primary treatment: non-surgical (n=1980) and surgical groups (n=3498). The distribution of patient/tumor characteristics and treatment variables with their relation to overall survival and proportional regression models were assessed to investigate the superiority of one approach over the other. Propensity score analysis adjusted for imbalance of covariates to create a well-matched-patient cohort.

FINDINGS

At 46months median follow-up, the 5-year overall survival was similar between both groups (73·8% vs. 75.7%; p=0.619) after applying propensity score analysis. On multivariate analysis, high Charlson comorbidity score, stage IIA disease, larger tumor size, positive lymph nodes and high-grade disease were significant predictors of poor outcome while older age and treatment approach were not.

INTERPRETATION

Our analysis suggests that surgery (followed by adjuvant RT or CRT) and definitive radiotherapy (with or without chemotherapy) result in equivalent survival. Prospective studies are warranted to establish this paradigm in the chemotherapy era.

Survival endpoints for young women with early stage uterine endometrioid carcinoma: a matched analysis

OBJECTIVES

Younger age is thought to be a favorable prognostic factor in women with endometrial carcinoma (EC). Survival endpoints were compared between two matched groups of patients with early stage EC: women 45 years or younger and women older than 45 years.

METHODS AND MATERIALS

Two matched groups of patients were created based on stage, grade, lymph node dissection and adjuvant management. Recurrence-free (RFS), disease-specific (DSS) and overall survival (OS) were calculated.

RESULTS

A total of 525 patients (88 younger patients and 437 older patients, matched 1:5) were included in this study. The two groups were well balanced except for less myometrial invasion in the younger patients. There were no significant differences between younger and older patients in regards to 5-year RFS (94% vs. 91%, p=0.6902). Similarly, there was no significant difference in regards to DSS (96% vs. 97%, p=0.9000). While 5-year OS was similar for both groups (89% vs. 89%, p=0.9942), 10-year OS was longer in the younger group (83% vs. 68% with p=0.13). On multivariate analysis for RFS, the presence of lymphovascular space invasion was the only predictor of shorter RFS (p=0.0007). Tumor grade (p=0.0002) and lower uterine segment involvement (p=0.0141) were independent predictors of shorter DSS. Older age (p<0.001) and stage II (p=0.01) were the only predictors of shorter OS.

CONCLUSIONS

When matched based on tumor stage, grade and adjuvant management, our study suggests that there is no difference in survival endpoints between younger and older patients with early stage endometrial carcinoma.

ACR Appropriateness Criteria® Adjuvant Management of Early-Stage Endometrial Cancer

These consensus guidelines on adjuvant radiotherapy for early-stage endometrial cancer were developed from an expert panel convened by the American College of Radiology. The American College of Radiology Appropriateness Criteria® are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer-reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method; and Grading of Recommendations Assessment, Development, and Evaluation, or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment. After a review of the published literature, the panel voted on three variants to establish best practices for the utilization of imaging, radiotherapy, and chemotherapy after primary surgery for early-stage endometrial cancer.

Trends in the utilization of adjuvant vaginal brachytherapy in women with early-stage endometrial carcinoma: Results of an updated period analysis of SEER data

PURPOSE

Adjuvant vaginal brachytherapy (VB) is a well-established and effective radiation treatment modality in women with early-stage endometrial carcinoma. We sought to evaluate and update published trends in the utilization of VB vs. other radiation therapy modalities (pelvic external beam radiation therapy (EBRT) or the combination of VB and pelvic EBRT using the National Cancer Institute's Surveillance, Epidemiology, and End Results database.

METHODS AND MATERIALS

The Surveillance, Epidemiology, and End Results database was queried for adult females with histologically confirmed International Federation of Gynecology and Obstetrics 1988 Stage I-II endometrial carcinoma diagnosed from 1995 to 2012 and treated definitively with hysterectomy and adjuvant radiation therapy. Chi-square tests were used to assess differences by radiation type (VB, EBRT, and VB + EBRT) and various demographic and clinical variables.

RESULTS

We identified 15,201 patients that met inclusion criteria. There was a significant overall increase in the use of VB was observed from 17.1% in 1995-2000 compared to 57.1% in 2007-2012 (p < 0.0001). Similarly, there was a proportional decrease in the use of EBRT from 54.0% to 25.5% (p < 0.0001) as well as in the use of VB + EBRT from 28.9% to 17.4% during the same period (p < 0.0001). The observed increase in utilization of VB was not limited to any variables (age, race, histological type, International Federation of Gynecology and Obstetrics stage, and the status of lymph node dissection [yes or no]) or the number of dissected lymph nodes.

CONCLUSIONS

In this large national database set, there continues to be an increasing trend for the use of VB in the adjuvant setting in women with early-stage endometrial carcinoma.

Adjuvant therapy of uterine clear cell carcinoma: a review

PURPOSE

Uterine clear-cell carcinoma (UCCC) is a rare subset of type II endometrial carcinoma with a poor prognosis relative to the most common type of endometrioid carcinoma. Due to its rarity, there has been limited direct evidence of the efficacy of specific adjuvant therapy posthysterectomy in women with UCCC. We present a review of current literature regarding adjuvant therapy of uterine clear cell carcinoma.

METHODS

We searched for English-language publications through Pubmed using a combination of the following key words: endometrial carcinoma, clear cell carcinoma, recurrence, prognosis, adjuvant therapy, radiation treatment and chemotherapy. Due to the rarity of UCCC, studies were not limited by design or number of patients.

RESULTS

There is a paucity of randomized prospective controlled studies focusing on UCCC adjuvant therapy. Findings have largely been derived from retrospective studies of type II endometrial carcinomas or all endometrial cancers as a group. Very few retrospective studies were found to focus on UCCC adjuvant therapy, although certain larger studies did have subset analyses of UCCC patients.

CONCLUSIONS

For early stage disease, locoregional radiotherapy, especially vaginal brachytherapy, has evidence of efficacy. The therapeutic gain of radiotherapy may be further improved with the addition of systemic chemotherapy. Evidence for combined radiation therapy with systemic chemotherapy in women with advanced stage UCCC has remained debatable. UCCC-specific studies are needed to determine the best adjuvant therapy for UCCC without the confounding effects of USC and other endometrial cancers.

ACR Appropriateness Criteria® Adjuvant Therapy in Vulvar Cancer

These American College of Radiology consensus guidelines were formed from an expert panel on the appropriate use of adjuvant therapy in vulvar cancer after primary treatment with surgery. The American College of Radiology Appropriateness Criteria® are evidence-based guidelines for specific clinical conditions that are reviewed every 3 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances where evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment. The panel reviewed the pertinent literature in vulvar cancer and voted on three variants to establish appropriate use of imaging, adjuvant radiation, including dose, fields, and technique, as well as adjuvant chemotherapy. This report will aid clinicians in selecting appropriate patients for adjuvant treatment and will provide guidelines for the optimal delivery of adjuvant radiation therapy and chemotherapy.

Solitary ovarian plasmacytoma. A case report and review of literature

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A patient with rare solitary ovarian plasmacytoma is reported

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Diagnostic work-up is mandatory to rule out ovarian involvement as part of multiple myeloma.

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After complete surgical resection, the prognosis appears to be very favorable.

Obesity and Lymphovascular Invasion in Women with Uterine Endometrioid Carcinoma

AIM

Obesity is classically linked to type I endometrial cancer (EC). Lymphovascular invasion (LVI) is a well-known adverse prognostic factor in EC. In other disease sites, it has been reported that obesity and LVI are strongly associated. The objective of the present study was to investigate the association between obesity and LVI in women with EC.

PATIENTS AND METHODS

For this Institutional Review Board (IRB)-approved study, we reviewed our prospectively-maintained uterine cancer database of 1,950 patients with EC International Federation of Gynecology and Obstetrics (FIGO) stages I-IV who underwent hysterectomy from 1/1988 through 12/2011. Bivariate and multivariate analyses were conducted to investigate the relationships between obesity, as measured by body mass index (BMI) at the time of hysterectomy and tumor features including LVI.

RESULTS

A total of 1,341 patients with uterine endometrioid carcinoma were identified. All patients underwent hysterectomy, and salpingoophrectomy with or without lymph node dissection. The median BMI for study patients was 34.3 (range=15.7-71.3) kg/m(2). 46.8% of the patients were morbidly obese. 625 patients (46.7%) were <60 years at diagnosis with a median BMI of 36.31 (range=19.7-69.8) kg/m(2) while the median BMI for women 61 years or older was 32.2 (15.7-71.3) kg/m(2) (p=0.002). In univariate analyses, high BMI was not significantly associated with LVI. In multivariate analyses, higher BMI was independently associated with younger age at diagnosis (odd ratio (OR)=0.97, 95% confidence interval (CI)=0.96-9.97) and the presence of lower tumor FIGO grade (OR=0.98, 95% CI=0.97-0.99).

CONCLUSION

Increased BMI was significantly associated with lower tumor grade and younger patient age at diagnosis. Increased body mass index was not associated with LVI. The higher prevalence of obesity in young women with EC is alarming.

A novel approach for evaluation of prostate deformation and associated dosimetric implications in IGRT of the prostate

PURPOSE

Prostate deformation is assumed to be a secondary correction and is typically ignored in the planning target volume (PTV) margin calculations. This assumption needs to be tested, especially when planning margins are reduced with daily image-guidance. In this study, deformation characteristics of the prostate and seminal vesicles were determined, and the dosimetric impact on treatment plans with different PTV margins was investigated.

METHODS

Ten prostate cancer patients were retrospectively selected for the study, each with three fiducial markers implanted in the prostate. Two hundred CBCT images were registered to respective planning CT images using a B-spline-based deformable image registration (DIR) software. A manual bony anatomy-based match was first applied based on the alignment of the pelvic bones and fiducial landmarks. DIR was then performed. For each registration, deformation vector fields (DVFs) of the prostate and seminal vesicles (SVs) were quantified using deformation-volume histograms. In addition, prostate rotation was evaluated and compared with prostate deformation. For a patient demonstrating small and large prostate deformations, target coverage degradation was analyzed in each of three treatment plans with PTV margins of 10 mm (6 mm at the prostate/rectum interface), as well as 5, and 3 mm uniformly.

RESULTS

Deformation of the prostate was most significant in the anterior direction. Maximum prostate deformation of greater than 10, 5, and 3 mm occurred in 1%, 17%, and 76% of the cases, respectively. Based on DVF-histograms, DVF magnitudes greater than 5 and 3 mm occurred in 2% and 27% of the cases, respectively. Deformation of the SVs was most significant in the posterior direction, and it was greater than 5 and 3 mm in 7.5% and 44.9% of the cases, respectively. Prostate deformation was found to be poorly correlated with rotation. Fifty percent of the cases showed rotation with negligible deformation and 7% of the cases showed significant deformation with minimal rotation (<3°). Average differences in the D95 dose to the prostate+SVs between the planning CT and CBCT images was 0.4%±0.5%, 3.0%±2.8%, and 6.6%±6.1%, respectively, for the plans with 10/6, 5, and 3 mm margins. For the case with both a large degree of prostate deformation (≈10% of the prostate volume) and rotation (≈8°), D95 was reduced by 0.5%±0.1%, 6.8%±0.6%, and 20.9%±1.6% for 10/6, 5, and 3 mm margin plans, respectively. For the case with large prostate deformation but negligible rotation (<1°), D95 was reduced by 0.4±0.3, 3.9±1.0, and 11.5±2.5 for 10/6, 5, and 3 mm margin plans, respectively.

CONCLUSIONS

Prostate deformation over a course of fractionated prostate radiotherapy may not be insignificant and may need to be accounted for in the planning margin design. A consequence of these results is that use of highly reduced planning margins must be viewed with caution.

Contouring variability of human- and deformable-generated contours in radiotherapy for prostate cancer

This study was designed to evaluate contouring variability of human-and deformable-generated contours on planning CT (PCT) and CBCT for ten patients with low-or intermediate-risk prostate cancer. For each patient in this study, five radiation oncologists contoured the prostate, bladder, and rectum, on one PCT dataset and five CBCT datasets. Consensus contours were generated using the STAPLE method in the CERR software package. Observer contours were compared to consensus contour, and contour metrics (Dice coefficient, Hausdorff distance, Contour Distance, Center-of-Mass [COM] Deviation) were calculated. In addition, the first day CBCT was registered to subsequent CBCT fractions (CBCTn: CBCT2-CBCT5) via B-spline Deformable Image Registration (DIR). Contours were transferred from CBCT1 to CBCTn via the deformation field, and contour metrics were calculated through comparison with consensus contours generated from human contour set. The average contour metrics for prostate contours on PCT and CBCT were as follows: Dice coefficient-0.892 (PCT), 0.872 (CBCT-Human), 0.824 (CBCT-Deformed); Hausdorff distance-4.75 mm (PCT), 5.22 mm (CBCT-Human), 5.94 mm (CBCT-Deformed); Contour Distance (overall contour)-1.41 mm (PCT), 1.66 mm (CBCT-Human), 2.30 mm (CBCT-Deformed); COM Deviation-2.01 mm (PCT), 2.78 mm (CBCT-Human), 3.45 mm (CBCT-Deformed). For human contours on PCT and CBCT, the difference in average Dice coefficient between PCT and CBCT (approx. 2%) and Hausdorff distance (approx. 0.5 mm) was small compared to the variation between observers for each patient (standard deviation in Dice coefficient of 5% and Hausdorff distance of 2.0 mm). However, additional contouring variation was found for the deformable-generated contours (approximately 5.0% decrease in Dice coefficient and 0.7 mm increase in Hausdorff distance relative to human-generated contours on CBCT). Though deformable contours provide a reasonable starting point for contouring on CBCT, we conclude that contours generated with B-Spline DIR require physician review and editing if they are to be used in the clinic.

An adaptive MR-CT registration method for MRI-guided prostate cancer radiotherapy

Magnetic Resonance images (MRI) have superior soft tissue contrast compared with CT images. Therefore, MRI might be a better imaging modality to differentiate the prostate from surrounding normal organs. Methods to accurately register MRI to simulation CT images are essential, as we transition the use of MRI into the routine clinic setting. In this study, we present a finite element method (FEM) to improve the performance of a commercially available, B-spline-based registration algorithm in the prostate region. Specifically, prostate contours were delineated independently on ten MRI and CT images using the Eclipse treatment planning system. Each pair of MRI and CT images was registered with the B-spline-based algorithm implemented in the VelocityAI system. A bounding box that contains the prostate volume in the CT image was selected and partitioned into a tetrahedral mesh. An adaptive finite element method was then developed to adjust the displacement vector fields (DVFs) of the B-spline-based registrations within the box. The B-spline and FEM-based registrations were evaluated based on the variations of prostate volume and tumor centroid, the unbalanced energy of the generated DVFs, and the clarity of the reconstructed anatomical structures. The results showed that the volumes of the prostate contours warped with the B-spline-based DVFs changed 10.2% on average, relative to the volumes of the prostate contours on the original MR images. This discrepancy was reduced to 1.5% for the FEM-based DVFs. The average unbalanced energy was 2.65 and 0.38 mJ cm(-3), and the prostate centroid deviation was 0.37 and 0.28 cm, for the B-spline and FEM-based registrations, respectively. Different from the B-spline-warped MR images, the FEM-warped MR images have clear boundaries between prostates and bladders, and their internal prostatic structures are consistent with those of the original MR images. In summary, the developed adaptive FEM method preserves the prostate volume during the transformation between the MR and CT images and improves the accuracy of the B-spline registrations in the prostate region. The approach will be valuable for the development of high-quality MRI-guided radiation therapy.