Sensory Outcomes after Neurotization in Nipple-sparing Mastectomy and Implant-based Breast Reconstruction.

Background: Mastectomy and breast reconstruction techniques continue to evolve to optimize aesthetic and reconstructive outcomes. However, the loss of sensation after mastectomy remains a major limitation. This article describes our evolution of a novel approach that we first described in 2019, combining recent advances in breast oncologic, reconstructive, and peripheral nerve surgery to optimize sensory outcomes. Methods: Nipple-sparing mastectomy was performed in all patients and involved preservation of lateral intercostal nerves when anatomy was favorable. When nerves could not be preserved without compromising oncologic safety, nipple-areolar complex neurotization was performed using allograft or intercostal autograft from a transected T3, T4, or T5, lateral intercostal nerve to identified subareolar nerve targets. Immediate, prepectoral, direct-to-implant reconstruction was then performed. Acroval one-point moving and one-point static pressure thresholds established baseline sensibility values, which were then repeated at multiple time points postoperatively. Results: Outcomes from 47 women (79 breasts) were assessed prospectively. Mean follow-up was 9.2 months (range 6-14 months). At 6 months postoperatively, over 80% of patients had good-to-excellent one-point moving as well as one-point static sensibility scores averaged across all areas tested. None of the patients developed persistent dysesthesia or clinical evidence of neuroma. Conclusions: This study represents the largest series reported to date of sensibility outcomes after nipple-sparing mastectomy and implant reconstruction with concurrent neurotization. Sensibility results show that this approach allows for preservation of high degrees of breast and nipple-areolar complex sensation in most patients.

Pretest PSA and Restaging PSMA PET/CT Predict Survival in Biochemically Recurrent Prostate Cancer.

BACKGROUND: A biochemical recurrence (BCR) risk model was created based on pretest prostate specific antigen (PSA) and groupings by restaging prostate specific membrane antigen (PSMA) PET/CT. METHODS: A cohort of 1216 BCR patients were analyzed for overall survival (OS) according to the PSA threshold and restaging PSMA PET/CT. A Cox regression analysis of OS was carried out to detect significant clinical characteristics. RESULTS: In the cohort, 271 patients had a pretest PSA of <0.5 ng/mL and 945 patients had higher PSA values. The restaging PSMA PET/CT was positive for 834 patients and negative for 369. Of 1203 patients, 133 (11%) died, including 19 of the 369 (5%) patients without positive sites on the restaging PSMA PET/CT, 82 of the 711 (12%) with 1-5 positive sites, and 32 of the 123 (26%) with >5 positive sites. In the Cox regression analysis, four variables significantly predicted OS: treatment center, International Society of Urologic Pathology (ISUP) grade, pretest PSA threshold, and the grouping of positive sites on the restaging PSMA PET/CT. CONCLUSIONS: The pretest PSA and PSMA PET/CT were important for the OS of the BCR patients. The findings argue for the new BCR risk model and serve as framework for ongoing trials.

Does lymph node assessment change the prognostic significance of substantial LVSI and p53 status in endometrial endometrioid carcinoma?

OBJECTIVE: The PORTEC-2 update suggested that substantial lymphovascular space invasion (LVSI) and abnormal p53 expression (p53abnl) predict for poorer outcomes and that these patients should be treated with external beam radiation therapy (EBRT). We aim to determine if patients with these risk factors who undergo a lymph node (LN) assessment show similar outcomes. METHODS: We retrospectively reviewed 126 patients with FIGO 2009 stage IA grade 3, stage IB grade 1-2, and stage IIIC (positive LN but no other stage II/III risk factors) endometrioid endometrial cancer who underwent LN assessment. Local (LR), regional recurrences (RR), and distant metastases were analyzed using competing risk methods, and overall survival (OS) was analyzed using Kaplan-Meier. RESULTS: Median follow-up time was 37.2 months. OS was significantly different between patients with and without p53abnl expression (16.7% versus 3.1% deceased), and between patients with and without LVSI (11.1% versus 1.5% deceased; p < 0.01 for both). The 2-year cumulative incidence of LR for patients with p53abnl versus wild type p53 and LVSI versus no LVSI was 11.1% (95% CI 0-25.6) versus 2.2% (95% CI 0-5.25; p = 0.04), and 11.4% (95% CI 2.0-20.9) versus 0%, respectively (p < 0.01). The 2-year cumulative RR in patients with LVSI versus no LVSI was 6.9% (95% CI 0-14.4) versus 0% (p = 0.05). No patients who completed pelvic RT experienced an in-field recurrence. CONCLUSIONS: Despite LN assessment, patients with high-intermediate risk early-stage or stage IIIC (with positive lymph nodes only but no other stage II or III risk factors) endometrial cancer with p53abnl expression and/or LVSI have worse outcomes. These patients may derive benefit from intensification with EBRT to improve local and pelvic control.

Galectin-1 Mediates Chronic STING Activation in Tumors to Promote Metastasis through MDSC Recruitment.

The immune system plays a crucial role in the regulation of metastasis. Tumor cells systemically change immune functions to facilitate metastatic progression. Through this study, we deciphered how tumoral galectin-1 (Gal1) expression shapes the systemic immune environment to promote metastasis in head and neck cancer (HNC). In multiple preclinical models of HNC and lung cancer in immunogenic mice, Gal1 fostered the establishment of a premetastatic niche through polymorphonuclear myeloid-derived suppressor cells (PMN-MDSC), which altered the local microenvironment to support metastatic spread. RNA sequencing of MDSCs from premetastatic lungs in these models demonstrated the role of PMN-MDSCs in collagen and extracellular matrix remodeling in the premetastatic compartment. Gal1 promoted MDSC accumulation in the premetastatic niche through the NF-κB signaling axis, triggering enhanced CXCL2-mediated MDSC migration. Mechanistically, Gal1 sustained NF-κB activation in tumor cells by enhancing stimulator of interferon gene (STING) protein stability, leading to prolonged inflammation-driven MDSC expansion. These findings suggest an unexpected protumoral role of STING activation in metastatic progression and establish Gal1 as an endogenous-positive regulator of STING in advanced-stage cancers. SIGNIFICANCE: Galectin-1 increases STING stability in cancer cells that activates NF-κB signaling and CXCL2 expression to promote MDSC trafficking, which stimulates the generation of a premetastatic niche and facilitates metastatic progression.

Outcomes and Imaging Analysis in Hepatocellular Carcinoma Treated With Stereotactic Body Radiation Therapy.

PURPOSE: Although arterial phase enhancement is commonly used to evaluate treatment response for hepatocellular carcinoma, it may not accurately describe response for lesions treated with stereotactic body radiation therapy (SBRT). We aimed to describe the post-SBRT imaging findings to better inform the optimal timing of salvage therapy after SBRT. METHODS AND MATERIALS: We retrospectively reviewed patients with hepatocellular carcinoma treated with SBRT from 2006 to 2021 at a single institution with available imaging showing lesions with characteristic arterial enhancement and portal venous washout. Patients were then stratified into 3 groups based on treatment: (1) concurrent SBRT and transarterial chemoembolization, (2) SBRT only, and (3) SBRT followed by early salvage therapy due to persistent enhancement. Overall survival was analyzed with the Kaplan-Meier method, and cumulative incidences were calculated with competing risk analysis. RESULTS: We included 82 lesions in 73 patients. The median follow-up time was 22.3 months (range, 2.2-88.1 months). The median time to overall survival was 43.7 months (95% confidence interval, 28.1-57.6 months) and median progression-free survival was 10.5 months (95% confidence interval, 7.2-14.0 months). There were 10 (12.2%) lesions that experienced local progression and there was no difference in rates of local progression between the 3 groups (P = .32). In the SBRT-only group, the median time to resolution of arterial enhancement and washout was 5.3 months (range, 1.6-23.7 months). At 3, 6, 9, and 12 months, 82%, 41%, 13%, and 8% of lesions, respectively, continued to show arterial hyperenhancement. CONCLUSIONS: Tumors treated with SBRT may continue to exhibit persistence of arterial hyperenhancement. Without an increase in size of enhancement, continued surveillance may be appropriate for these patients.

Feasibility of the Audio-Visual Assisted Therapeutic Ambience in Radiotherapy (AVATAR) System for Anesthesia Avoidance in Pediatric Patients: A Multicenter Trial.

PURPOSE: The Audio-Visual Assisted Therapeutic Ambience in Radiotherapy (AVATAR) system was the first published radiation therapy (RT)-compatible system to reduce the need for pediatric anesthesia through video-based distraction. We evaluated the feasibility of AVATAR implementation and effects on anesthesia use, quality of life, and anxiety in a multicenter pediatric trial. METHODS AND MATERIALS: Pediatric patients 3 to 10 years of age preparing to undergo RT at 10 institutions were prospectively enrolled. Children able to undergo at least 1 fraction of RT using AVATAR without anesthesia were considered successful (S). Patients requiring anesthesia for their entire treatment course were nonsuccessful (NS). The PedsQL3.0 Cancer Module (PedsQL) survey assessed quality of life and was administered to the patient and guardian at RT simulation, midway through RT, and at final treatment. The modified Yale Preoperative Anxiety Scale (mYPAS) assessed anxiety and was performed at the same 3 time points. Success was evaluated using the χ2 test. PedsQL and mYPAS scores were assessed using mixed effects models with time points evaluated as fixed effects and a random intercept on the subject. RESULTS: Eighty-one children were included; median age was 7 years. AVATAR was successful at all 10 institutions and with photon and proton RT. There were 63 (78%) S patients; anesthesia was avoided for a median of 20 fractions per patient. Success differed by age (P = .04) and private versus public insurance (P < .001). Both patient (P = .008) and parent (P = .006) PedsQL scores significantly improved over the course of RT for patients aged 5 to 7. Anxiety in the treatment room decreased for both S and NS patients over RT course (P < .001), by age (P < .001), and by S versus NS patients (P < .001). CONCLUSIONS: In this 10-center prospective trial, anesthesia avoidance with AVATAR was 78% in children aged 3 to 10 years, higher than among age-matched historical controls (49%; P < .001). AVATAR implementation is feasible across multiple institutions and should be further studied and made available to patients who may benefit from video-based distraction.

Correction: von Eyben et al. A Risk Model for Patients with PSA-Only Recurrence (Biochemical Recurrence) Based on PSA and PSMA PET/CT: An Individual Patient Data Meta-Analysis. Cancers 2022, 14, 5461.

In the original publication [...].

Validation of a Resectability Scoring System for Prediction of Pancreatic Adenocarcinoma Surgical Outcomes.

BACKGROUND: The most used pancreatic cancer (PC) resectability criteria are descriptive in nature or based solely on dichotomous degree of involvement (< 180° or > 180°) of vessels, which allows for a high degree of subjectivity and inconsistency. METHODS: Radiographic measurements of the circumferential degree and length of tumor contact with major peripancreatic vessels were retrospectively obtained from pre-treatment multi-detector computed tomography (MDCT) images from PC patients treated between 2001 and 2015 at two large academic institutions. Arterial and venous scores were calculated for each patient, then tested for a correlation with tumor resection and R0 resection. RESULTS: The analysis included 466 patients. Arterial and venous scores were highly predictive of resection and R0 resection in both the training (n = 294) and validation (n = 172) cohorts. A recursive partitioning tree based on arterial and venous score cutoffs developed with the training cohort was able to stratify patients of the validation cohort into discrete groups with distinct resectability probabilities. A refined recursive partitioning tree composed of three resectability groups was generated, with probabilities of resection and R0 resection of respectively 94 and 73% for group A, 61 and 35% for group B, and 4 and 2% for group C. This resectability scoring system (RSS) was highly prognostic, predicting median overall survival times of 27, 18.9, and 13.5 months respectively for patients in RSS groups A, B, and C (p < 0.001). CONCLUSIONS: The proposed RSS was highly predictive of resection, R0 resection, and prognosis for patients with PC when tested against an external dataset.

Patterns of Progression in Patients With Newly Diagnosed Glioblastoma Treated With 5-mm Margins in a Phase 1/2 Trial of 5-Fraction Stereotactic Radiosurgery With Concurrent and Adjuvant Temozolomide.

PURPOSE: In patients with newly diagnosed glioblastoma (GBM), tumor margins of at least 20 mm are the standard of care. We sought to determine the pattern of tumor progression in patients treated with 5-fraction stereotactic radiosurgery with 5-mm margins. METHODS AND MATERIALS: Thirty adult patients with newly diagnosed GBM were treated with 5-fraction stereotactic radiosurgery in escalated doses from 25 to 40 Gy with a 5-mm total treatment margin. Progression was scored as "in-field" if the recurrent tumor was within or contiguous with the 5-mm margin, "marginal" if between 5 and 20 mm, and "distant" if entirely occurring greater than 20 mm. As geometric patterns of progression do not reflect the biologic dose received, we calculated the minimum equi-effective dose in 2 Gy (EQD2) per day at the site of tumor recurrence. Progression was "dosimetrically in-field" if covered by a minimum EQD2 per day of 48 Gy10. RESULTS: From 2010 to 2016, 27 patients had progressed. Progression was in-field in 17 (63%), marginal in 3 (11%), and distant in 7 (26%) patients. In the 3 patients with marginal progression, the minimum EQD2 to recurrent tumor were 48 Gy10, 56 Gy10 (both considered dosimetrically in-field), and 7 Gy10 (ie, dosimetrically out-of-field). Median overall survival was 12.1 months for in-field (95% confidence interval [CI], 8.9-17.6), 15.1 months (95% CI, 10.1 to not achieved) for marginal, and 21.4 months (95% CI, 11.2-33.5) for distant progression. Patients with radiation necrosis were less likely to have in-field progression (1 of 7; 14%) compared with those without radiation necrosis (16 of 20; 80%; P = .003); those with necrosis had a median overall survival of 27.2 months (95% CI, 11.2-48.3) compared with 11.7 months (95% CI, 8.9-17.6) for patients with no necrosis (P = .077). CONCLUSIONS: In patients with newly diagnosed GBM treated with a 5-mm clinical target volume margin, 3 patients (11%) had marginal progression within 5 to 20 mm; only 1 patient (4%) may have dosimetrically benefitted from conventional 20-mm margins. Radiation necrosis was associated with in-field tumor control.

NFE2L2 Mutations Enhance Radioresistance in Head and Neck Cancer by Modulating Intratumoral Myeloid Cells.

Radiotherapy (RT) is one of the primary treatments of head and neck squamous cell carcinoma (HNSCC), which has a high-risk of locoregional failure (LRF). Presently, there is no reliable predictive biomarker of radioresistance in HNSCC. Here, we found that mutations in NFE2L2, which encodes Nrf2, are associated with a significantly higher rate of LRF in patients with oral cavity cancer treated with surgery and adjuvant (chemo)radiotherapy but not in those treated with surgery alone. Somatic mutation of NFE2L2 led to Nrf2 activation and radioresistance in HNSCC cells. Tumors harboring mutant Nrf2E79Q were substantially more radioresistant than tumors with wild-type Nrf2 in immunocompetent mice, whereas the difference was diminished in immunocompromised mice. Nrf2E79Q enhanced radioresistance through increased recruitment of intratumoral polymorphonuclear myeloid-derived suppressor cells (PMN-MDSC) and reduction of M1-polarized macrophages. Treatment with the glutaminase inhibitor CB-839 overcame the radioresistance induced by Nrf2E79Q or Nrf2E79K. RT increased expression of PMN-MDSC-attracting chemokines, including CXCL1, CXLC3, and CSF3, in Nrf2E79Q-expressing tumors via the TLR4, which could be reversed by CB-839. This study provides insights into the impact of NFE2L2 mutations on radioresistance and suggests that CB-839 can increase radiosensitivity by switching intratumoral myeloid cells to an antitumor phenotype, supporting clinical testing of CB-839 with RT in HNSCC with NFE2L2 mutations. SIGNIFICANCE: NFE2L2 mutations are predictive biomarkers of radioresistance in head and neck cancer and confer sensitivity to glutaminase inhibitors to overcome radioresistance.

Time to resolution of iodine-123 metaiodobenzylguanidine (123 I-MIBG) avidity and local control outcomes for high-risk neuroblastoma following radiation therapy.

INTRODUCTION: 123 I-MIBG scan is used in neuroblastoma (NB) to monitor treatment response. Time to resolution of 123 I-MIBG avidity after radiation therapy (RT) is unknown. We sought to determine time to resolution of 123 I-MIBG avidity after RT and local failure (LF) rate. METHODS: We performed a retrospective review of children with high-risk NB who underwent 123 I-MIBG scans pre- and post-RT from 2003 to 2019. Time from RT to resolution of 123 I-MIBG activity was analysed. LF and cumulative incidence of local progression (CILP) after RT stratified by site, presence of residual disease and use of boost RT were determined. RESULTS: Forty-two patients with median age 3.9 years (1.9-4.7 years) were included, with median follow-up time 3.9 years (1.4-6.9). Eighty-six lesions were treated with RT to median dose of 21.6 Gy. Eighteen of 86 lesions were evaluable for time to resolution of MIBG avidity after RT, with median resolution time of 78 days (36-208). No LF occurred among 26 patients who received RT to primary sites after GTR, versus 4/12 (25%) patients treated with residual primary disease. 2-year CILP was 19% (12% primary disease 25% metastatic disease (P = 0.18)). 2-year CILP for non-residual primary, residual primary, non-residual metastatic and residual metastatic lesions was 0%, 42%, 11% and 30% respectively (P = 0.01) and for boosted and non-boosted residual lesions was 29% and 35% (P = 0.44). CONCLUSION: Median time to MIBG resolution after RT was 78 days. Primary lesions without residual disease had excellent local control. LF rate was higher after RT for residual disease, with no benefit for boost RT.

Long-term Outcomes of Diffuse or Recurrent Tenosynovial Giant Cell Tumor Treated with Postoperative External Beam Radiation Therapy.

PURPOSE: Tenosynovial giant cell tumor (TGCT) is a rare proliferative disorder of synovial membrane that previously was known as pigmented villonodular synovitis. Primary treatment involves surgical resection; however, complete removal of all disease involvement is difficult to achieve. Radiation may be useful to reduce the risk of recurrence. We report and update our institutional experience treating diffuse and recurrent TGCT with postsurgical external beam radiation therapy. METHODS AND MATERIALS: We performed a retrospective chart review of 30 patients with TGCT from 2003 to 2019 treated with radiation therapy. Each patient was evaluated for demographics, radiation treatment parameters, surgical management, complications, and outcome. RESULTS: With mean follow-up of 82 months (range, 3-211), 24 patients (80%) who underwent surgery followed by radiation therapy did not experience any further relapse, and all 30 patients achieved local control (100%) with additional salvage therapy after radiation therapy. The most common site of disease was the knee (n = 22, 73%), followed by the ankle (n = 5, 16%) and the hand (n = 3, 10%). Seven patients (24%) presented at time of initial diagnosis and 23 (76%) presented with recurrent disease after surgical resection, with an average of 2.6 surgical procedures before radiation therapy. After resection, 18 of 30 patients (67%) demonstrated residual TGCT by imaging. The median radiation therapy dose delivered was 36 Gy (range, 34-36 Gy) in 1.8 to 2.5 Gy/fractions for 4 weeks. In the assessment of posttreatment joint function, 26 sites (86%) exhibited excellent or good function, 2 (7%) fair, and 2 poor (7%) as determined by our scoring system. There were no cases of radiation-associated malignancy. CONCLUSIONS: Among patients with diffuse or recurrent TGCT, postsurgical external beam radiation therapy provided excellent local control and good functional status, with minimal treatment-related complications. Postsurgical radiation therapy is a well-tolerated noninvasive treatment that should be considered after maximal cytoreductive resection to prevent disease progression and recurrence.

Radiation Oncology Virtual Education Rotation (ROVER) 2.0 for Residents: Implementation and Outcomes.

The COVID-19 pandemic catalyzed the integration of a virtual education curriculum to support radiation oncologists in training. We report outcomes from Radiation Oncology Virtual Education Rotation (ROVER) 2.0, a supplementary virtual educational curriculum created for radiation oncology residents globally. A prospective cohort of residents completed surveys before and after the live virtual webinar sessions (pre- and post-surveys, respectively). Live sessions were structured as complex gray-zone cases across various core disease sites. Resident demographics and responses were summarized using means, standard deviations, and proportions. Nine ROVER sessions were held from October 2020 to June 2021. A total of 1487 registered residents completed the pre-survey, of which 786 attended the live case discussion and 223 completed post-surveys. A total of 479 unique radiation oncology residents (of which 95, n = 19.8%, were international attendees) from 147 institutions (national, n = 81, 55.1%; international, n = 66, 44.9%) participated in the sessions. There was similar participation across post-graduate year (PGY) 2 through 5 (range n = 86 to n = 105). Of the 122 unique resident post-surveys, nearly all reported learning through the virtual structure as "very easy" or "easy" (97.5%, n = 119). A majority rated the ROVER 2.0 educational sessions to be "valuable or "very valuable" (99.2%, n = 121), and the panelists-attendee interaction as "appropriate" (97.5%, n = 119). Virtual live didactics aimed at radiation oncology residents are feasible. These results suggest that the adoption of the ROVER 2.0 curricula may help improve radiation oncology resident education.

A Risk Model for Patients with PSA-Only Recurrence (Biochemical Recurrence) Based on PSA and PSMA PET/CT: An Individual Patient Data Meta-Analysis.

An individual patient meta-analysis followed 1216 patients with PSA-only recurrence (biochemical recurrence, BCR) restaged with [68Ga]Ga-PSMA-11 PET/CT before the salvage treatment for median 3.5 years and analyzed the overall survival (OS). A new risk model included a good risk group with a prescan PSA < 0.5 ng/mL (26%), an intermediate risk group with a prescan PSA > 0.5 ng/mL and a PSMA PET/CT with 1 to 5 positive sites (65%), and a poor risk group with a prescan PSA > 0.5 ng/mL and a PSA PET/CT with > 5 positive sites (9%) (p < 0.0001, log rank test). The poor risk group had a five-year OS > 60%. Adding a BCR risk score by the European Association of Urology did not significantly improve the prediction of OS (p = 0.64). In conclusion, the restaging PSMA PET/CT markedly predicted the 5-year OS. The new risk model for patients with PSA-only relapse requires a restaging PSMA PET/CT for patients with a prescan PSA > 0.5 ng/mL and has a potential use in new trials aiming to improve the outcome for patients with PSA-only recurrence who have polysites prostate cancer detected on PSMA PET/CT.

Local control of brain metastases with osimertinib alone in patients with EGFR-mutant non-small cell lung cancer.

PURPOSE: Although osimertinib has excellent intracranial activity in metastatic non-small cell lung cancer (NSCLC) with exon 19 deletion or L858R EGFR alterations, measures of local control of brain metastases are less well-reported. We describe lesion-level outcomes of brain metastases treated with osimertinib alone. METHODS: We retrospectively reviewed patients with EGFR-mutant NSCLC with untreated brain metastasis measuring ≥ 5 mm at the time of initiating osimertinib. Cumulative incidence of local recurrence in brain (LRiB) was calculated with death as a competing risk, and univariable and multivariable analyses were conducted to identify factors associated with LRiB. RESULTS: We included 284 brain metastases from 37 patients. Median follow-up was 20.1 months. On initial MRI after starting osimertinib, patient-level response was complete response (CR) in 11 (15%), partial response (PR) in 33 (45%), stable disease (SD) in 18 (25%) and progressive disease (PD) in 11 (15%). The 1-year cumulative incidence of LRiB was 14% (95% CI 9.9-17.9) and was significantly different in patients with a CR (0%), PR (4%), and SD (11%; p = 0.02). Uncontrolled primary tumor (adjusted hazard ratio [aHR] 3.78, 95% CI 1.87-7.66; p < 0.001), increasing number of prior systemic therapies (aHR 2.12, 95% CI 1.49-3.04; p < 0.001), and higher ECOG score (aHR 7.8, 95% CI 1.99-31.81; p = 0.003) were associated with LRiB. CONCLUSIONS: Although 1-year cumulative incidence of LRiB is < 4% with a CR or PR, 1-year cumulative incidence of LRiB is over 10% for patients with less than a PR to osimertinib on initial MRI. These patients should be followed closely for need for additional treatment such as stereotactic radiosurgery.

Incidence of Brain Metastases in Women Treated With Neoadjuvant Chemotherapy for Breast Cancer: Implications for Screening.

PURPOSE: Patients with metastatic breast cancer may develop brain metastases. Our study identified high-risk patients to refine selection criteria for BM screening approaches. PATIENTS: We reviewed breast cancer patients treated with neoadjuvant chemotherapy (NAC) at a single university center between 2005 and 2019. METHODS: Competing risks analysis was performed with the Fine and Gray model to analyze the cumulative incidence of BM and loco-regional recurrence. Overall survival (OS) and progression-free survival (PFS) were calculated using Kaplan-Meier and log-rank tests. Multivariable analysis was performed with Cox proportional hazards regression to identify factors predictive for development of BM. Statistical significance was determined as a 2-sided P value of <.05. RESULTS: In total, 112 patients experienced distant failure (DF) and 49 patients developed BM. Twenty patients with BM (41%) presented with symptoms requiring craniotomy +/- whole brain radiation treatment. Patients with BM were significantly more likely to have local (P < .01) and regional (P < .01) failure. On multivariable analysis, age <40 years (P = .011), presence of lung metastases (P < .0001), and residual nodal disease with >4 lymph nodes positive after NAC (P = .024) all predicted for increased likelihood of BM. Patients with these criteria had higher likelihoods of having BM (P = .013) and worse PFS (P = .044). On multivariable analysis for OS, presence of lung metastases was the most significant predictor of poor outcome (P < .0001). CONCLUSION: We propose a study of screening brain MRI for young (<40 years) patients with breast cancer receiving NAC and patients who develop metastatic disease post-NAC, especially those with lung involvement.

The Combination of Radiotherapy and Complement C3a Inhibition Potentiates Natural Killer cell Functions Against Pancreatic Cancer.

Pancreatic cancer is one of the deadliest cancers, against which current immunotherapy strategies are not effective. Herein, we analyzed the immune cell composition of the tumor microenvironment of pancreatic cancer samples in The Cancer Genome Atlas and found that the presence of intratumoral NK cells correlates with survival. Subsequent analysis also indicated that NK cell exclusion from the microenvironment is found in a high percentage of clinical pancreatic cancers and in preclinical models of pancreatic cancer. Mechanistically, NK cell exclusion is regulated in part by complement C3a and its receptor signaling. Inhibition of the C3a receptor enhances NK cell infiltration in syngeneic mouse models of pancreatic cancer resulting in tumor growth delay. However, tumor growth inhibition mediated by NK cells is not sufficient alone for complete tumor regression, but is potentiated when combined with radiation therapy. Our findings indicate that although C3a inhibition is a promising approach to enhance NK cell-based immunotherapy against pancreatic cancer, its combination with radiation therapy hold greater therapeutic benefit.

Dynamic Contrast-Enhanced Ultrasound Modeling of an Analog to Pseudo-Diffusivity in Intravoxel Incoherent Motion Magnetic Resonance Imaging.

Tumor perfusion and vascular properties are important determinants of cancer response to therapy and thus various approaches for imaging perfusion are being explored. In particular, Intravoxel Incoherent Motion (IVIM) MRI has been actively researched as an alternative to Dynamic-Contrast-Enhanced (DCE) CT and DCE-MRI as it offers non-ionizing, non-contrast-based perfusion imaging. However, for repetitive treatment assessment in a short time period, high cost, limited access, and inability to scan at the bedside remain disadvantages of IVIM MRI. We propose an analysis framework that may enable 3D DCE Ultrasound (DCE-US) - low cost, bedside imaging with excellent safety record - as an alternative modality to IVIM MRI for the generation of DCE-US based pseudo-diffusivity maps in acoustically accessible anatomy and tumors. Modelling intravascular contrast propagation as a convective-diffusive process, we reconstruct parametric maps of pseudo-diffusivity by solving a large-scale fully coupled inverse problem without any assumptions regarding local constancy of the reconstructed parameters. In a mouse tumor model, we demonstrate that the 3D DCE-US pseudo-diffusivity is repeatable, sensitive to treatment with an antiangiogenic agent, and moderately correlated to histological measures of perfusion and angiogenesis.

Rectosigmoid Cancer-Rectal Cancer or Sigmoid Cancer?

OBJECTIVES: We aimed to determine the optimal treatment for patients with locally advanced rectosigmoid cancers, and to determine whether this can be guided by distance from anal verge (AV) and/or anatomic landmarks such as the sacral promontory and peritoneal reflection (PR). MATERIALS AND METHODS: We retrospectively reviewed patients with T3-T4 and/or node-positive rectosigmoid cancers who underwent surgery from 2006 to 2018 with available pelvic imaging. We included tumors at 9 to 20 cm from the AV on either staging imaging, or colonoscopy. Patients were stratified into those who received neoadjuvant therapy, and those who underwent upfront surgery. Comparisons of characteristics were performed using χ 2 test and Fischer exact test. Locoregional failure (LRF) and overall survival were compared using Cox regressions and Kaplan-Meier analysis. RESULTS: One hundred sixty-one patients were included. Ninety-seven patients had neoadjuvant therapy, and 64 patients had upfront surgery. Median follow-up time was 45.1 months. Patients who had neoadjuvant therapy had tumors that were higher cT stage ( P <0.01) with more positive/close circumferential resection margins seen on imaging by radiologists (28.9% vs. 1.6% , P =0.015). The 2-year rate of LRF, distant metastases, or overall survival was not significantly different between the 2 groups. None of 15 patients with tumors below the PR treated with neoadjuvant therapy had LRF, but 1 (25%) of 4 patients with tumors below the PR treated with adjuvant therapy experienced LRF ( P =0.05). CONCLUSIONS: Patients with tumors below the PR may benefit more from neoadjuvant therapy. The PR on imaging may be a reliable landmark in addition to the distance from the AV to determine the most appropriate treatment option.

Characterization of Metastatic Non-Small Cell Lung Cancer and Oligometastatic Incidence in an Era of Changing Treatment Paradigms.

PURPOSE: Because of the limitations of current staging systems and evolving definitions, there are limited data on oligometastatic non-small cell lung cancer (NSCLC) epidemiology. The purpose of this study was to evaluate metastatic disease burden and the incidence of oligometastatic disease using recent clinical trial eligibility criteria. METHODS AND MATERIALS: A cohort of patients with metastatic NSCLC, diagnosed from 2016 to 2019, were randomly sampled from a curated tumor registry. Definitions for oligometastatic disease were obtained from relevant clinical trials. The Stanford Cancer Institute Research Database was used to identify baseline patient factors, systemic and local therapy, extent and location of metastatic lesions, and survival outcomes. RESULTS: Among 120 patients presenting with metastatic NSCLC, the majority had de novo metastatic disease (75%) with a median of 4 metastatic lesions involving 3 organ systems. Of these, 37.5% would have been eligible for at least 1 oligometastatic trial, with 28.3% meeting criteria for the MD Anderson Cancer Center trial, 20.0% for NRG-LU002, 6.7% for SINDAS, and 16.7% for SABR-COMET. By adding malignant pleural effusions and early progression as exclusionary criteria, only 54.1% of patients with ≤3 synchronous metastases were eligible for consideration of local therapy. Early progression on systemic therapy was associated with worse survival (10.0 vs 42.4 months; P < .001), whereas presence of malignant pleural effusions was not. Of those tumors identified as oligometastatic, 44.4% received local therapy and 28.9% underwent ablative therapy to all sites. There was a trend toward greater overall survival (44.4 vs 24.9 months; P = .055) and progression-free survival (8.0 vs 5.4 months; P = .06) in patients meeting eligibility for at least 1 oligometastatic trial. CONCLUSIONS: Around 48% of patients with metastatic NSCLC had ≤3 metastases at presentation and 28% met clinical trial criteria for oligometastatic disease. Future research is needed to better define the oligometastatic state and identify patients most likely to benefit from local therapy.