Prognostic performance of FIGO 2023 endometrial carcinoma staging: a comparison to FIGO 2009 staging in the setting of known and unknown molecular classification.

AIMS: The 2023 FIGO staging criteria for endometrial cancer (EC) introduced marked changes from the 2009 version. The full implication of these changes for patient diagnosis and treatment is unknown. We evaluate the differences in staging and prognostication between the two systems, with and without inclusion of molecular classification. METHODS AND RESULTS: We assigned (1) FIGO 2009, (2) 2023 molecular-agnostic and (3) 2023 molecular-informed stages to 404 fully staged and molecularly classified patients with EC. Disease-specific and progression/relapse-free survival were analysed via the Kaplan-Meier method and compared with log-rank testing; 118 of 252 (47%) FIGO 2009 stage I patients were upstaged based on histopathological findings alone. Stage I/II subgroup survival distribution analysis showed a worse prognosis in FIGO 2023 IIB and IIC patients. In the molecular-informed FIGO 2023 system, three of 15 (20%) POLE-mutated stage I/II cases were downstaged from FIGO 2009 and eight (53%) were downstaged from molecular-agnostic FIGO 2023. Fifty-one of 60 (85%) p53-abnormal tumours were upstaged from the FIGO 2009, whereas 13 of 60 (22%) were upstaged from the 2023 molecular-agnostic stage. Molecular classification improved prognostic stratification for both 2009 and 2023 FIGO systems. CONCLUSIONS: Downstaging based on POLE mutation more accurately represents patient outcomes. However, in the absence of known POLE status, applying molecular-agnostic FIGO 2023 criteria for stage I/II disease should be conducted with caution. For aggressive histotypes, additionally reporting FIGO 2009 stage should be considered. Upstaging based on substantial lymphovascular space invasion, aggressive histotype with any myometrial invasion and abnormal p53 improves prognostic discernment. Further subdivisions within stage I/II provide minimal additional prognostic information.

Adjuvant radiation therapy in early-stage endometrial cancer with abnormal beta-catenin expression is associated with improved local control.

OBJECTIVES: Emerging data suggests that abnormal (nuclear) ß-catenin expression in some settings is associated with poorer outcomes. Our study aimed to verify the significance of abnormal ß-catenin expression in early-stage endometrial cancer patients and determine if adjuvant radiation therapy (RT) improves local control. METHODS: We identified 213 patients with FIGO 2018 stage I-II endometrioid endometrial cancer who underwent surgery from 2009 to 2021 with ß-catenin expression assessed. Vaginal, regional, and distant recurrences were analyzed using competing risk methods, and overall survival was analyzed using Kaplan-Meier. RESULTS: Median follow up was 53.2 months; 6.9% experienced vaginal, 8.2% regional, and 7.4% distant recurrence. For the entire cohort, abnormal ß-catenin expression was significantly associated with vaginal recurrence and remained significant on multivariate analysis (p = 0.03). There were 114 patients in the no specific molecular profile (NSMP) subgroup, and abnormal ß-catenin expression was present in 46.5%. In the NSMP subgroup, abnormal ß-catenin expression was associated with increased rates of vaginal recurrence (p = 0.06). Abnormal ß-catenin expression in the NSMP subgroup was significant on multivariate analysis for vaginal recurrence (p = 0.04). RT significantly decreased vaginal recurrences in the entire cohort in patients with abnormal ß-catenin expression (0%) versus wild type expression (17.5%; p = 0.03). In the NSMP subgroup 0% of patients who received RT versus 20.9% of patients who did not receive RT experienced a vaginal recurrence (p = 0.03). CONCLUSION: Use of adjuvant RT for stage I-II NSMP endometrial cancer with abnormal ß-catenin expression improved local control. RT should be considered in these patients to decrease risk of vaginal recurrences.

Prospective molecular classification of endometrial carcinomas: institutional implementation, practice, and clinical experience.

The comprehensive genomic analysis of endometrial carcinoma (EC) by The Cancer Genome Atlas (TCGA) led to the discovery of four distinct and prognostically significant molecular subgroups. Molecular classification has the potential to improve risk-stratification when integrated with clinicopathologic features and has recently been included in national and international patient management EC guidelines. Thus, the adoption of molecular classification into routine pathologic and clinical practice is likely to grow significantly in the upcoming years. Establishing an efficient and standardized workflow for performing molecular classification on ECs, and reporting both the molecular and histologic findings in an integrative manner, is imperative. Here we describe our effort to implement rapid and routine molecular classification on all ECs diagnosed at our institution. To this effect, we performed immunohistochemistry as a surrogate marker for identifying genetic and/or epigenetic alterations in DNA mismatch repair (e.g., MLH1, PMS2, MSH6, MSH2), and TP53 genes. In addition, we have developed and employed a single-gene POLE SNaPshot assay, which is a rapid and analytically sensitive method for detecting select POLE exonuclease domain mutations (EDMs). We report our molecular testing workflow and integrative reporting system as well as the clinicopathologic and molecular features of 310 ECs that underwent routine molecular classification at our institution. The 310 ECs were molecularly classified as follows: 15 (5%) POLE mutant (POLEmut), 79 (25%) mismatch repair-deficient (MMRd), 135 (44%) no specific molecular profile (NSMP), and 81 (26%) p53 abnormal (p53abnl). This work provides an initial framework for implementing routine molecular classification of ECs.

Imaging to optimize gynecological radiation oncology.

Gynecological cancers have particularly benefited from the increasing use of imaging to guide radiation treatment planning for both external beam radiation and brachytherapy. While the different gynecological cancers have varying use of imaging, certain trends predominate. CT represents an economical choice for evaluating initial disease extent or potential metastasis at follow-up, particularly for endometrial and ovarian cancers. F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/CT is particularly useful for assessing the initial disease extent and longer term treatment response of squamous predominant cancers, including cervical, vaginal, and vulvar cancers. With its excellent pelvic soft tissue discrimination, MRI provides the greatest assistance in evaluating the local extent of gynecological tumors, including initial evaluation for non-operative endometrial and vulvar cancer, and assessment before, after and during brachytherapy for cervix, locally recurrent endometrial, and primary vaginal cancers. With more limited availability of MRI, ultrasound can also help guide brachytherapy, particularly during procedures. The benefits of using imaging to better spare bone marrow or earlier assessment of treatment response are topics still being explored, in particular for cervical cancer. As imaging along with radiation oncology technologies continue to evolve and develop, such as with MRI-linacs and ultra high dose rate (FLASH) radiation, we may continue to see increasing use of imaging for advancing gynecological radiation oncology.

Executive summary of the American Radium Society appropriate use criteria for management of uterine clear cell and serous carcinomas.

BACKGROUND: Uterine clear cell and serous carcinomas have a high propensity for locoregional and distant spread, tend to be more advanced at presentation, and carry a higher risk of recurrence and death than endometrioid cancers. Limited prospective data exist to guide evidence-based management of these rare malignancies. OBJECTIVE: The American Radium Society sought to summarize evidence-based guidelines developed by a multidisciplinary expert panel that help to guide the management of uterine clear cell and serous carcinomas. METHODS: The American Radium Society Appropriate Use Criteria presented in this manuscript were developed by a multidisciplinary expert panel using an extensive analysis of current published literature from peer-reviewed journals. A well-established methodology (modified Delphi) was used to rate the appropriate use of diagnostic and therapeutic procedures for the management of uterine clear cell and serous carcinomas. RESULTS: The primary treatment for non-metastatic uterine clear cell and serous carcinomas is complete surgical staging, with total hysterectomy, salpingo-oophorectomy, omentectomy, and lymph node staging. Even in early-stage disease, patients with uterine clear cell and serous carcinomas have a worse prognosis than those with type I endometrial cancers, warranting consideration for adjuvant therapy regardless of the stage. Given the aggressive nature of these malignancies, and until further research determines the most appropriate adjuvant therapy, it may be reasonable to counsel patients about combined-modality treatment with systemic chemotherapy and radiotherapy. CONCLUSION: Patients diagnosed with uterine clear cell and serous carcinomas should undergo complete surgical staging. Multimodal adjuvant therapies should be considered in the treatment of both early-stage and advanced-stage disease. Further prospective studies or multi-institutional retrospective studies are warranted to determine optimal sequencing of therapy and appropriate management of patients based on their unique risk factors. Long-term surveillance is indicated due to the high risk of locoregional and distant recurrence.

Defining the survival benefit of adjuvant pelvic radiotherapy and chemotherapy versus chemotherapy alone in stages III-IVA endometrial carcinoma.

OBJECTIVES: To determine which patients with locoregionally advanced endometrial cancer may benefit from pelvic external beam radiotherapy (EBRT) in addition to chemotherapy compared to chemotherapy alone. METHODS: Patients with FIGO stages III-IVA endometrial carcinoma between 2004 and 2016 who underwent at least total hysterectomy and adjuvant multiagent chemotherapy were identified in the National Cancer Database. The primary outcome was overall survival according to receipt of pelvic EBRT, analyzed using the Kaplan-Meier method and Cox multivariable regression. RESULTS: In total, 13,270 patients were identified (62% pure endometrioid, 38% serous/clear cell or mixed histology; 22.6% stage IIIA, 4.7% stage IIIB, 71.2% stage IIIC, 1.5% stage IVA), of whom 40% received pelvic EBRT. In univariable analysis, EBRT was associated with absolute 5-year survival increases of 5% and 9% in the endometrioid and non-endometrioid cohorts, respectively (P < 0.0001). In multivariable analyses stratified by stage and histology, patients with a significant benefit from EBRT were stage IIIC (specifically IIIC2) endometrioid (adjusted hazard ratio [HR] 0.73, P = 0.01) and stages IIIB and IIIC non-endometrioid (adjusted HR 0.52, P = 0.01 and adjusted HR 0.79, P < 0.0001). The benefit of EBRT in node-positive patients persisted in those who underwent more extensive lymphadenectomy. CONCLUSIONS: Stages III-IVA endometrial cancer comprised a heterogeneous population with respect to the added benefit of radiotherapy compared to chemotherapy alone. Patients with stage IIIC2 endometrioid and stages IIIB-C non-endometrioid cancer may be most likely to benefit from pelvic EBRT.

National patterns of care and cancer-specific outcomes of adjuvant treatment in patients with serous and clear cell endometrial carcinoma.

OBJECTIVES: To investigate outcomes of adjuvant therapy for serous and clear cell endometrial carcinoma, as prior studies are limited by sample size and/or patient heterogeneity. National guidelines permit substantial variations in treatment, suggesting the need for additional data. METHODS: Patients with FIGO stages I-III serous or clear cell uterine carcinoma who underwent at least total hysterectomy were identified in SEER-Medicare. Adjuvant external beam radiation, brachytherapy, and chemotherapy were determined using SEER fields and Medicare claims. The primary outcome was death from endometrial cancer (cancer-specific mortality [CSM]) evaluated using Gray's test (univariable analysis, UVA) and Fine-Gray regression (multivariable analysis, MVA). RESULTS: A total of 1789 patients (1437 serous, 352 clear cell) were identified. In stages I-II patients (n = 1188), brachytherapy was significant for survival in UVA (P = 0.03) and MVA (P = 0.02). Additionally, in the subset with serous histology (n = 947), chemotherapy was also significant in UVA (P = 0.002) and approached significance in MVA (P = 0.05). The 4-year CSM for stages I-II serous cancers was 25% without brachytherapy or chemotherapy, 15% with one, and 9% with both (P ≤ 0.05 for all pairwise comparisons). In stage III patients (n = 601), chemotherapy was significant in UVA (P = 0.002) and MVA (P = 0.006). Most (81%) patients underwent lymph node dissection, which predicted lower CSM in stage III (P = 0.001) but not stages I-II patients. CONCLUSIONS: Our results suggest brachytherapy benefits stages I-II serous/clear cell cancers, chemotherapy benefits stage III serous/clear cell cancers, and both chemotherapy and brachytherapy benefit stages I-II serous cancers.

Benefit of Cisplatin With Definitive Radiotherapy in Older Women With Cervical Cancer.

BACKGROUND: Cisplatin with definitive radiotherapy (RT) is considered the standard of care for cervical cancer; however, older women are frequently undertreated and have worse outcomes compared with younger patients. Because women aged ≥65 years have been disproportionately underrepresented in clinical trials, uncertainties exist regarding how much they benefit from the addition of cisplatin to RT. PATIENTS AND METHODS: Women aged ≥65 years with nonmetastatic cervical cancer treated with definitive external-beam RT and brachytherapy were identified in the SEER-Medicare database. Death attributable to cervical cancer (cancer-specific mortality [CSM]) was evaluated against competing risks of death using Gray's test. Propensity score analysis and the Fine-Gray multivariable regression model were used to adjust for baseline differences, including comorbidity. RESULTS: The total cohort comprised 826 patients, of whom 531 (64%) received cisplatin, 233 (28%) were FIGO stage I, 374 (45%) were stage II, and 219 (27%) were stage III-IVA. Older age and chronic kidney disease significantly predicted omission of cisplatin. Virtually all cisplatin dosing was weekly, with a median of 5 cycles. Death from cervical cancer was significantly lower with cisplatin than without (5-year CSM, 31% vs 39%; P=.02; adjusted hazard ratio, 0.72; P=.02), which persisted in propensity score analysis. Receiving ≥5 cycles was required for benefit, as no difference in CSM was seen in patients receiving 1 to 4 cycles versus no cisplatin. Subgroup analyses revealed that the benefit of cisplatin persisted in women aged ≥75 years and those with early-stage disease. Incidence of cytopenia, nausea/vomiting, and hypovolemia increased in patients treated with cisplatin. CONCLUSIONS: Administration of cisplatin with definitive RT in women aged ≥65 years was associated with a significant benefit in the incidence of death attributable to cervical cancer, despite competing risks for mortality in an older population. Receiving at least 5 cycles of weekly cisplatin was required for benefit.

Prognostic Significance of P16 Expression and P53 Expression in Primary Vaginal Cancer.

To evaluate the correlation between p16 expression and clinical outcomes in patients with primary vaginal cancer treated with definitive radiotherapy. P16 immunohistochemical was performed on 25 patient samples and recorded from pathology reports in 7 patients. P53 immunohistochemical was performed on 3 p16-negative samples. Baseline characteristics were compared using the Fisher exact test. Outcomes were compared using log-rank tests, and cox proportional hazards models. Survival and recurrence analysis was performed with the Kaplan-Meier method and cumulative incidence estimates. P16 expression was positive in 29 patients and negative in 3 patients. Two of the p16-negative tumors showed positive expression of p53. The median overall survival, progression-free survival and 2-yr cumulative incidence of recurrence were 66 mo [95% confidence interval (CI), 31-96], 34 mo (95% CI, 21-86), and 19% (95% CI, 7%-34%), respectively. P16-positive tumors had higher median overall survival and progression-free survival compared with p16-negative tumors (82 vs. 31 mo, P=0.02 and 35 vs 16 mo, P=0.04, respectively). The 2-yr cumulative incidence of recurrence was 14% for p16-positive tumors compared with 67% for p16-negative tumors (P=0.07). On univariable analysis, p16-negative status, age older than 65, and advanced stage were associated with inferior overall survival. P16 negativity is an independent predictor of inferior overall survival. P16-positive vaginal cancers have a better prognosis and decreased incidence of recurrence compared with p16-negative tumors. These prognostic findings associated with p16-negative vaginal cancers will need to be confirmed in larger patient cohorts.

Extent of lymphovascular space invasion may predict lymph node metastasis in uterine serous carcinoma.

OBJECTIVES: Emerging evidence suggests that extent of lymphovascular space invasion (LVSI) predicts for risk of lymph node metastasis in endometrioid uterine cancers. However, this correlation remains unknown in the setting of uterine serous carcinoma (USC). We sought to examine the association between extent of LVSI and other histopathologic characteristics with risk of nodal metastasis for women with USC. MATERIALS/METHODS: Pathological data from all cases of uterine serous carcinoma between July 1998 to July 2015 at our institution were reviewed. Descriptive, univariate, and multivariate logistic regression analysis of selected pathologic features were performed. RESULTS: 88 patients with USC underwent total abdominal or laparoscopic hysterectomy, bilateral salpingo-oophorectomy, and selective lymphadenectomy. Surgical staging revealed the following FIGO stage distributions: I (41%), II (8%), III (32%), IV (19%). LVSI was present in 44 (50%) patients. 36 patients (41%) had LN metastases with median number of total nodes removed of 17 (range, 1-49). On univariate analysis, depth of myometrial invasion, LVSI, tumor size, and cervical stromal involvement were significantly associated with nodal involvement. In a multivariate model, LVSI (OR 6.25, 95% CI 2.2-18.0, p<0.01) and cervical stromal involvement (OR 3.33, 95% CI 1.10-10.0, p=0.03) were the only factors that remained significant. Among patients with LVSI-positive disease, extensive LVSI was associated with increased risk of nodal involvement compared to focal LVSI (90% vs 29%, p=0.04). CONCLUSIONS: Presence and extent of LVSI, and cervical stromal invasion are important predictors for lymph node metastasis in uterine serous carcinoma.

Nomogram to Predict Risk of Lymph Node Metastases in Patients With Endometrioid Endometrial Cancer.

Pelvic lymphadenectomy in early-stage endometrial cancer is controversial, but the findings influence prognosis and treatment decisions. Noninvasive tools to identify women at high risk of lymph node metastasis can assist in determining the need for lymph node dissection and adjuvant treatment for patients who do not have a lymph node dissection performed initially. A retrospective review of surgical pathology was conducted for endometrioid endometrial adenocarcinoma at our institution. Univariate and multivariate logistic regression analysis of selected pathologic features were performed. A nomogram to predict for lymph node metastasis was constructed. From August 1996 to October 2013, 296 patients underwent total abdominal or laparoscopic hysterectomy, bilateral salpingo-oophorectomy, and selective lymphadenectomy for endometrioid endometrial adenocarcinoma. Median age at surgery was 62.7 yr (range, 24.9-93.6 yr). Median number of lymph nodes removed was 13 (range, 1-72). Of all patients, 38 (12.8%) had lymph node metastases. On univariate analysis, tumor size ≥4 cm, grade, lymphovascular space involvement, cervical stromal involvement, adnexal or serosal or parametrial involvement, positive pelvic washings, and deep (more than one half) myometrial invasion were all significantly associated with lymph node involvement. In a multivariate model, lymphovascular space involvement, deep myometrial invasion, and cervical stromal involvement remained significant predictors of nodal involvement, whereas tumor size of ≥4 cm was borderline significant. A lymph node predictive nomogram was constructed using these factors. Our nomogram can help estimate risk of nodal disease and aid in directing the need for additional surgery or adjuvant therapy in patients without lymph node surgery. Lymphovascular space involvement is the most important predictor for lymph node metastases, regardless of grade, and should be consistently assessed.

Impact of socioeconomic status and ethnic enclave on cervical cancer incidence among Hispanics and Asians in California.

OBJECTIVE: This study aimed to evaluate the incidence of cervical cancer by nativity [United States (US) versus non-US], neighborhood socioeconomic status and ethnic enclave among Hispanics and Asians in California. METHODS: Using data from the California Cancer Registry, information on all primary invasive cervical cancer (Cca) patients diagnosed in California from January 1, 1990 through December 31, 2004 was obtained. We analyzed the influence of enclave, socioeconomic status and nativity on Cca incidence. RESULTS: Among the 22,189 Cca cases diagnosed between 1990 and 2004, 50% were non-Hispanic white, 39% Hispanic and 11% Asian women, and 63% US-born. Seventy percent of the Cca cases were squamous cell carcinoma, 19% adenocarcinoma and 11% other histologies. Higher incidence of Cca was observed in high enclave (76%) and low socioeconomic status (70%) neighborhoods. By ethnic group, US-born women showed lower rates of squamous cell carcinoma compared to foreign-born women. Hispanics living in low socioeconomic and high enclave had 12.7 times higher rate of Cca than those living in high socioeconomic, low enclave neighborhoods. For Asian women incidence rates were 6 times higher in the low socioeconomic, high enclave neighborhoods compared to those living in high socioeconomic, low enclave neighborhoods. CONCLUSION: More targeted outreach to increase Pap smear screening and human papilloma virus vaccination for women living in high enclave neighborhoods can help decrease the incidence of Cca in these groups of women.

Design approach and benefits of the 3D-printed vaginal individualized applicator (VIA).

PURPOSE: Interstitial gynecologic brachytherapy necessitates precise needle placement, requiring time and expertise. We aimed to simplify interstitial procedures and facilitate optimal needle distribution with individualized vaginal templates to guide interstitial needles. MATERIALS/METHODS: We developed the 3D-printed vaginal individualized applicator (VIA), a cylindrical template containing individualized internal channels that guide interstitial needles to cover the tumor extent. Eight patients underwent VIA only interstitial implants (VIA only), and five intact cervical cases were treated using tandem and customized VIA (VIA + T). Procedure length, number of needles utilized and dosimetric measures were evaluated. RESULTS: VIA was successfully designed and used clinically for 24 procedures (8 VIA only, 16 VIA + T). Average procedure needle insertion time reduced from 80.9 min for traditional interstitial to 42.9 min for VIA only, approximately 47% shorter with a similar mean high risk CTV volume (28.3 cc VIA only vs. 32.4 cc) and excellent dosimetry with average CTV V100% (94.3% and 94.4%). VIA + T was particularly useful in patients with small vaginal canals and large tumor size. For the five VIA + T patients average tumor size was 68.0cc (range 26.6-143.5 cc). VIA + T procedures were approximately 20% shorter than hybrid procedures with other applicators with mean length of 20.1 min and an average of 6.8 needles (range 3-12). CONCLUSION: Our novel 3D-printed VIA facilitates gynecologic interstitial brachytherapy by simplifying needle placement, reducing procedure time, and maintaining excellent dosimetry. VIA can be customized for various clinical scenarios, particularly beneficial for large tumors or small vaginal canals.

Development and clinical implementation of simple needle attachment post placement interstitial template (SNAPP-IT) enabling a shorter, more direct needle path while preserving tumor visualization.

PURPOSE: Historical gynecologic interstitial brachytherapy templates block direct tumor visualization during needle placement, presenting an opportunity for clinical innovation to develop a novel interstitial template allowing direct tumor visualization during needle insertion. METHODS AND MATERIALS: We designed and implemented a novel interstitial template, simple needle attachment post placement interstitial template (SNAPP-IT), that allowed direct visualization of the target vaginal tumor during interstitial needle placement while maintaining the ability to individually secure needles to the template, allow a vaginal cylinder, suture holes for securing to the perineum, MRI compatibility and sterilizable for repeat use. Procedure outcomes including procedure time, needle path lengths, and plan dosimetry were prospectively captured in a patient database. RESULTS: Forty gynecologic interstitial brachytherapy cases were recorded (20 SNAPP-IT, 20 traditional templates). Needle insertion depth was reduced using the SNAPP-IT in comparison with traditional interstitial templates (11.8 cm vs. 3.6 cm, p < 0.0001). The average CTV volume was 25.6 cc for SNAPP-IT and 20.7 cc for traditional; both methods averaged a similar number of needles (15.8, 15.6). Dosimetric constraints were similarly met in both treatment groups. Procedures performed using the SNAPP-IT were shorter compared with those performed with traditional interstitial devices (83.4 minutes vs. 100.7 minutes) and there were no post-operative infections in the SNAPP-IT group. CONCLUSIONS: Implementation of a novel gynecologic interstitial brachytherapy template (SNAPP-IT) reduced procedure times, allowed direct tumor visualization, and decreased needle insertion depth. SNAPP-IT provides a useful alternative approach for vaginal interstitial brachytherapy, may increase brachytherapist efficiency with complex procedures and potentially expands access to interstitial brachytherapy.

Parametric response mapping of co-registered intravoxel incoherent motion magnetic resonance imaging and positron emission tomography in locally advanced cervical cancer undergoing concurrent chemoradiation therapy.

Background and Purpose: Intravoxel-incoherent-motion (IVIM) magnetic-resonance-imaging (MRI) and positron-emission-tomography (PET) have been investigated independently but not voxel-wise to evaluate tumor microenvironment in cervical carcinoma patients. Whether regionally combined information of IVIM and PET offers additional predictive benefit over each modality independently has not been explored. Here, we investigated parametric-response-mapping (PRM) of co-registered PET and IVIM in cervical cancer patients to identify sub-volumes that may predict tumor shrinkage to concurrent-chemoradiation-therapy (CCRT). Materials and Methods: Twenty cervical cancer patients (age: 63[41-85]) were retrospectively evaluated. Diffusion-weighted-images (DWIs) were acquired on 3.0 T MRIs using a free-breathing single-shot-spin echo-planar-imaging (EPI) sequence. Pre- and on-treatment (∼after four-weeks of CCRT) MRI and pre-treatment FDG-PET/CT were acquired. IVIM model-fitting on the DWIs was performed using a Bayesian-fitting simplified two-compartment model. Three-dimensional rigidly-registered maps of PET/CT standardized-uptake-value (SUV) and IVIM diffusion-coefficient (D) and perfusion-fraction (f) were generated. Population-means of PET-SUV, IVIM-D and IVIM-f from pre-treatment-scans were calculated and used to generate PRM via a voxel-wise joint-histogram-analysis to classify voxels as high/low metabolic-activity and with high/low (hi/lo) cellular-density. Similar PRM maps were generated for SUV and f. Results: Tumor-volume (p < 0.001) significantly decreased, while IVIM-f (p = 0.002) and IVIM-D (p = 0.03) significantly increased on-treatment. Pre-treatment tumor-volume (r = -0.45,p = 0.04) and PRM-SUVhi D lo (r = -0.65,p = 0.002) negatively correlated with ΔGTV, while pre-treatment IVIM-D (r = 0.64,p = 0.002), PRM-SUVlo f hi (r = 0.52,p = 0.02), and PRM-SUVlo D hi (r = 0.74,p < 0.001) positively correlated with ΔGTV. Conclusion: IVIM and PET was performed on cervical cancer patients undergoing CCRT and we observed that both IVIM-f and IVIM-D increased during treatment. Additionally, PRM was applied, and sub-volumes were identified that were related to ΔGTV.

Prognostic Effect of Mismatch Repair Status in Early-Stage Endometrial Cancer Treated With Adjuvant Radiation: A Multi-institutional Analysis.

PURPOSE: The aim of this work was to report the effect of mismatch repair (MMR) status on outcomes of patients with stage I-II endometrioid endometrial adenocarcinoma (EEC) who receive adjuvant radiation therapy. METHODS AND MATERIALS: This is a multi-institutional retrospective cohort study across 11 institutions in North America. Patients with known MMR status and stage I-II EEC status postsurgical staging were included. Overall survival (OS) and recurrence-free survival (RFS) rates were estimated via the Kaplan-Meier method. Univariable and multivariable analyses were performed via Cox proportional hazard models for RFS and OS. Statistical analyses were conducted using SPSS version 27. RESULTS: In total, 744 patients with a median age at diagnosis of 65 years (IQR, 58-71) were included. Most patients were White (69.4%) and had Federation of Obstetrics and Gynecology 2009 stage I (84%) and Federation of Obstetrics and Gynecology grade 1 to 2 (73%). MMR deficiency was reported in 234 patients (31.5%), whereas 510 patients (68.5%) had preserved MMR. External beam radiation therapy with or without vaginal brachytherapy was delivered to 186 patients (25%), whereas 558 patients (75%) received vaginal brachytherapy alone. At a median follow-up of 43.5 months, the estimated crude OS and RFS rates for the entire cohort were 92.5% and 84%, respectively. MMR status was significantly correlated with RFS. RFS was inferior for MMR deficiency compared with preserved MMR (74.3% vs 88.6%, P < .001). However, no difference in OS was seen (90.8% vs 93.2%, P = .5). On multivariable analysis, MMR deficiency status was associated with worse RFS (hazard ratio, 1.86; P = .001) but not OS. CONCLUSIONS: MMR status was independently associated with RFS but not OS in patients with early-stage EEC who were treated with adjuvant radiation therapy. These findings suggest that differential approaches to surveillance and/or treatment based on MMR status could be warranted.

Primary squamous cell carcinoma of the vagina: prognostic factors, treatment patterns, and outcomes.

OBJECTIVE: Primary squamous cell carcinoma (SCCA) of the vagina is a rare malignancy with limited data to guide treatment. We evaluated prognostic factors and outcomes for patients with primary vaginal SCCA treated with definitive radiation therapy at a single institution. METHODS: A retrospective analysis was performed on patients treated for primary vaginal SCCA from 1959 to 2011. RESULTS: Ninety-one patients with primary vaginal SCCA were treated with definitive radiation therapy. Thirty-eight patients had FIGO stage I, 28 stage II, 13 stage III, and 12 stage IV disease. The mean total dose was 70.1 Gy. Two-year overall survival (OS), locoregional control rate (LRC), and distant metastasis-free survival by stage were, respectively: stage I: 96.2%, 80.6%, 87.5%; stage II: 92.3%, 64.7%, 84.6%; stage III: 66.6%, 44.4%, 50.0%; and stage IV: 25.0%, 14.3%, 25.0%. Treatment with total dose over 70 Gy was associated with improved OS (p=0.0956) and LRC (p=0.055). There was a significant difference in median dose received by patients who developed grade 3/4 toxicity compared to those who did not (82.9 Gy versus 70.0 Gy, p=0.0019). None of the 10 patients treated with IMRT experienced locoregional recurrence or grade 3/4 toxicity. Tumor size larger than 4 cm was associated with worse OS (p=0.0034) and LRC (p=0.006). CONCLUSIONS: Our analysis suggests that the optimal dose for definitive treatment of SCCA of the vagina lies between 70 and 80 Gy. Treatment with IMRT may allow for dose escalation with reduced toxicity and excellent LRC. Tumor size over 4 cm is associated with inferior outcomes and may require additional treatment modalities.

Treatment approach and outcomes of vaginal melanoma.

OBJECTIVE: To describe the characteristics of primary vaginal melanoma patients in the Surveillance, Epidemiology, and End Result database and to determine the outcome from the treatment approaches. MATERIALS/METHODS: From the Surveillance, Epidemiology, and End Result registry, 201 patients with vaginal melanoma were identified. Patients' characteristics and prognostic factors including age, race, extent of surgery, and use of radiation therapy were obtained. RESULTS: The median age was 68 years (range, 28-100 years). The population was 73% white, 11% black, and 16% Asian/American Indian. International Federation of Gynecology and Obstetrics staging results were stage I (46%), stage II (18%), stage III (3%), stage IVA (3%), stage IVB (12%), and unknown (18%). Treatment approach included surgical resection of the primary site in 70%, whereas 35% of the patients underwent lymph node resection. Approximately 40% of the patients received radiotherapy, which was primarily used in the adjuvant setting. Overall survival at 2 and 5 years was 24% and 15%, respectively. Presence of lymph nodes at diagnosis was associated with worse overall survival (hazard ratio, 1.98; P = 0.02). Adjuvant radiation did not offer a statistically significant overall survival advantage compared to surgery alone. CONCLUSIONS: Vaginal melanoma is a rare diagnosis primarily affecting the elderly. Overall survival is low even for patients presenting with disease limited to the vagina. Lymph node involvement at diagnosis is strongly predictive of worse overall survival. Most patients are treated with surgical resection with varying use of adjuvant radiotherapy. Further research is needed to identify the etiology and improve the outcome of this aggressive disease.

Developing Next-Generation 3-Dimensional Printing for Cervical Cancer Hybrid Brachytherapy: A Guided Interstitial Technique Enabling Improved Flexibility, Dosimetry, and Efficiency.

PURPOSE: We developed a 3-dimensionally (3D) printed tandem anchored radially guiding interstitial template (TARGIT) to increase the simplicity of intracavitary/interstitial technique for tandem-and-ovoid (T&O) procedures in cervical cancer brachytherapy. This study compared dosimetry and procedure logistics between T&O implants using the original TARGIT versus the next-generation TARGIT-Flexible-eXtended (TARGIT-FX) 3D-printed template designed for practice-changing ease-of-use with further simplified needle insertion and increased flexibility in needle placement. METHODS AND MATERIALS: This single-institution retrospective cohort study included patients undergoing T&O brachytherapy as part of definitive cervical cancer treatment. Procedures used the original TARGIT from November 2019 through February 2022 and the TARGIT-FX from March 2022 through November 2022. The FX design features full extension to the vaginal introitus with 9 needle channels and allows for needle additions or depth adjustments intraprocedure and after computed tomography/magnetic resonance imaging. RESULTS: A total of 148 implants were performed, 68 (46%) with TARGIT and 80 (54%) with TARGIT-FX, across 41 patients. Across implants, the TARGIT-FX achieved higher mean V100% (+2.8%, P = .0019), and across patients, the TARGIT-FX achieved higher D90 (+2.0 Gy, P = .037) and higher D98 (+2.7 Gy, P = .016) compared with the original TARGIT. Doses to organs at risk were overall similar between templates. Procedure times for TARGIT-FX implants were 30% shorter on average than for those using the original TARGIT (P < .0001), and 28% shorter on average for the subset of implants with high-risk clinical target volume ≥30 cc (P = .013). All residents (100%, N = 6) surveyed regarding the TARGIT-FX indicated ease-of-use for needle insertion and interest in applying the technique in future practice. CONCLUSIONS: The TARGIT-FX achieved shorter procedure times with increased tumor coverage and similar normal tissue sparing compared with the previously applied TARGIT and illustrates the potential of 3D printing to enhance efficiency and shorten the learning curve for intracavitary/interstitial procedure technique in cervical cancer brachytherapy.

Dosimetric Evaluation of Organs at Risk From SAVE Protocol.

PURPOSE: The objective of this work was to evaluate dosimetric characteristics to organs at risk (OARs) from short-course adjuvant vaginal cuff brachytherapy (VCB) in early endometrial cancer compared with standard of care (SOC) in a multi-institutional prospective randomized trial. METHODS AND MATERIALS: SAVE (Short Course Adjuvant Vaginal Brachytherapy in Early Endometrial Cancer Compared to Standard of Care) is a prospective, phase 3, multisite randomized trial in which 108 patients requiring VCB were randomized to an experimental short-course arm (11 Gy × 2 fractions [fx] to surface) and SOC arm. Those randomized to the SOC arm were subdivided into treatment groups based on treating physician discretion as follows: 7 Gy × 3 fx to 5 mm, 5 to 5.5 Gy × 4 fx to 5 mm, and 6 Gy × 5 fx to surface. To evaluate doses to OARs of each SAVE cohort, the rectum, bladder, sigmoid, small bowel, and urethra were contoured on planning computed tomography, and doses to OARs were compared by treatment arm. Absolute doses for each OAR and from each fractionation scheme were converted to 2 Gy equivalent dose (EQD23). Each SOC arm was compared with the experimental arm separately using 1-way analysis of variance, followed by pairwise comparisons using Tukey's honestly significant difference test. RESULTS: The experimental arm had significantly lower doses for rectum, bladder, sigmoid, and urethra compared with the 7 Gy × 3 and 5 to 5.5 Gy × 4 fractionation schemes; however, the experimental arm did not differ from the 6 Gy × 5 fractionation scheme. For small bowel doses, none of the SOC fractionation schemes were statistically different than the experimental. The highest EQD23 doses to the examined OARs were observed to come from the most common dose fractionation scheme of 7 Gy × 3 fx. With a short median follow-up of 1 year, there have been no isolated vaginal recurrences. CONCLUSIONS: Experimental short-course VCB of 11 Gy × 2 fx to the surface provides a comparable biologically effective dose to SOC courses. Experimental short-course VCB was found to reduce or be comparable to D2cc and D0.1cc EQD23 doses to rectum, bladder, sigmoid, small bowel, and urethra critical structures. This may translate into a comparable or lower rate of acute and late adverse effects.