Detection of Residual Peritoneal Metastases Following Cytoreductive Surgery Using Pegsitacianine, a pH-Sensitive Imaging Agent: Final Results from a Phase II Study

BACKGROUND

For patients with peritoneal carcinomatosis, extent of disease and completeness of cytoreductive surgery (CRS) are major prognostic factors for long-term survival. Assessment of these factors could be improved using imaging agents. Pegsitacianine is a pH-sensitive polymeric micelle conjugated to the fluorophore indocyanine green. The micelle disassembles in acidic microenvironments, such as tumors, resulting in localized fluorescence unmasking. We assessed the utility of pegsitacianine in detecting residual disease following CRS.

PATIENTS AND METHODS

NCT04950166 was a phase II, non-randomized, open-label, multicenter US study. Patients eligible for CRS were administered an intravenous dose of pegsitacianine at 1 mg/kg 24-72 h before surgery. Following CRS, the peritoneal cavity was reexamined under near-infrared (NIR) illumination to evaluate for fluorescent tissue. Fluorescent tissue identified was excised and evaluated by histopathology. The primary outcome was the rate of clinically significant events (CSE), defined as detection of histologically confirmed residual disease excised with pegsitacianine or a revision in the assessment of completeness of CRS. Secondary outcomes included acceptable safety and pegsitacianine performance.

RESULTS

A total of 53 patients were screened, 50 enrolled, and 40 were evaluable for CSE across six primary tumor types. Residual disease was detected with pegsitacianine in 20 of 40 (50%) patients. Pegsitacianine showed high sensitivity and was well tolerated with no serious adverse events (SAEs). Transient treatment-related, non-anaphylactic infusion reactions occurred in 28% of patients.

CONCLUSIONS

Pegsitacianine was well tolerated and facilitated the recognition of occult residual disease following CRS. The high rate of residual disease detected suggests that the use of pegsitacianine augmented surgeon assessment and performance during CRS.

Neoadjuvant therapy for resectable melanoma

The standard of care for patients with resectable stage III/IV melanoma classically included upfront resection with adjuvant therapy. However, in more recent years, the amount of systemic therapies available for neoadjuvant use for these patients has increased. This article reviewed clinical trials investigating neoadjuvant therapy for patients with resectable stage III/IV melanoma. The outcomes of these trials have identified optimal treatment regimens to maximise patient response and minimize toxicities. Additionally, the date demonstrate advantages to neoadjuvant treatment compared to adjuvant therapy alone. Further research is needed to utilize a patient's response to neoadjuvant treatment for prognostication and creation of an individualized treatment plan.

Delayed time to radiation and overall survival in Merkel cell carcinoma

BACKGROUND

Clinically localized Merkel cell carcinoma (MCC) is commonly treated with surgical excision and radiotherapy. The relationship between time to adjuvant radiotherapy and overall survival (OS) remains understudied.

METHODS

This retrospective study used data from the National Cancer Database (2006-2019). Patients with clinically localized MCC who received surgical excision and adjuvant radiotherapy were included. Multivariate regressions were used to account for various patient and tumor factors. The primary outcome was 5-year OS, and the secondary outcome was time from diagnosis to adjuvant radiation (TTR).

RESULTS

Of the 1965 patients included, most were male (n = 1242, 63.2%) and white (n = 1915, 97.5%), and the median age was 74 years (interquartile range [IQR]: 66-81). The median TTR was 83 days (IQR: 65-106). A total of 83.6% of patients received radiotherapy to the primary site, 21.3% to the draining nodal basin, 17.1% to both, and 12.2% whose target location of radiotherapy was not recorded in the data. TTR of ≥79 days (the 45th percentile) was associated with worse OS on both univariate and multivariate analyses (log-rank p = 0.0014; hazard ratio [HR]: 1.258, 95% confidence interval [CI]: 1.055-1.500, p = 0.010). This persisted on sub-analyses of patients <80 years old (n = 1407; HR: 1.380, 95% CI: 1.080-1.764, p = 0.010) and of patients with Charlson comorbidity index (CCI) of 0 (n = 1411; HR: 1.284, 95% CI: 1.034-1.595, p = 0.024). Factors associated with delayed TTR included greater age (p = 0.039), male sex (p = 0.04), CCI > 1 (p = 0.036), academic facility (p < 0.001), rural county (p = 0.034), AJCC T2 stage (p = 0.010), negative margins (p = 0.017), 2+ pathologically positive regional nodes (p = 0.011), and margin size >2 cm (p = 0.015).

CONCLUSIONS

Delayed radiotherapy (≥79 days) was associated with worse OS of MCC patients. Further study in controlled cohorts is needed to ascertain this relationship.

Upregulation of exosome secretion from tumor-associated macrophages plays a key role in the suppression of anti-tumor immunity

Macrophages play a pivotal role in tumor immunity. We report that reprogramming of macrophages to tumor-associated macrophages (TAMs) promotes the secretion of exosomes. Mechanistically, increased exosome secretion is driven by MADD, which is phosphorylated by Akt upon TAM induction and activates Rab27a. TAM exosomes carry high levels of programmed death-ligand 1 (PD-L1) and potently suppress the proliferation and function of CD8+ T cells. Analysis of patient melanoma tissues indicates that TAM exosomes contribute significantly to CD8+ T cell suppression. Single-cell RNA sequencing analysis showed that exosome-related genes are highly expressed in macrophages in melanoma; TAM-specific RAB27A expression inversely correlates with CD8+ T cell infiltration. In a murine melanoma model, lipid nanoparticle delivery of small interfering RNAs (siRNAs) targeting macrophage RAB27A led to better T cell activation and sensitized tumors to anti-programmed cell death protein 1 (PD-1) treatment. Our study demonstrates tumors use TAM exosomes to combat CD8 T cells and suggests targeting TAM exosomes as a potential strategy to improve immunotherapies.

Evaluating Changes in Surgical Outcomes for Patients With Inflammatory Bowel Disease Following Medicaid Expansion

BACKGROUND

Little is known about the impact of Medicaid expansion on the surgical care of inflammatory bowel disease. We sought to determine whether Medicaid expansion is associated with improved postsurgical outcomes for patients with inflammatory bowel disease undergoing a colorectal resection.

METHODS

We performed a risk-adjusted difference-in-difference study examining postsurgical outcomes for patients ages 26 to 64 with Crohn's disease or ulcerative colitis undergoing a colorectal resection across 15 states that did and did not expand Medicaid before (2012-2013) and after (2016-2018) policy reform. Primary study outcomes included 30-day readmission and postoperative complication.

RESULTS

Study population included 11 394 patients with inflammatory bowel disease that underwent a colorectal resection. States that underwent Medicaid expansion were associated with a rise in Medicaid enrollment following policy reform (11.8% pre-Medicaid expansion vs 19.7% post-Medicaid expansion). Difference-in-difference analysis revealed a statistically significant lower odds of 30-day readmission in patients undergoing a colorectal resection in expansion states following policy reform relative to patients in nonexpansion states prior to reform (odds ratio, 0.56; 95% confidence interval, 0.36-0.86). No changes in odds of postoperative complication were noted across expansion and nonexpansion states.

CONCLUSIONS

Medicaid expansion is associated with a rise in Medicaid enrollment in expansion states following policy reform. There were greater improvements in postoperative outcomes associated with patients in expansion states following policy reform relative to patients in nonexpansion states prior to reform, which may have been related to improved perioperative care and medical management.

Impact of travel burden on the treatment of stage I and II breast cancer: A National Cancer Database analysis

BACKGROUND

Although historic studies of state registries have demonstrated decreased radiation therapy use for patients with breast cancer living further away from radiation facilities, the association between travel distance and breast cancer treatment in a modern national cohort remains unknown.

METHODS

Female patients with estrogen receptor/progesterone receptor positive and human epidermal growth factor receptor 2 negative pathologic stages I to II breast cancer were identified from the National Cancer Database (2018-2020) and dichotomized by distance ≤20 miles or >20 miles (75th percentile) from the treatment facility. The association between travel distance and type of surgery and treatment administered was analyzed by univariate and multivariate logistic regression and after 1:1 propensity matching.

RESULTS

Of the 293,318 patients identified for inclusion, the median age was 63 years, and most patients (n = 190,567, 65%) lived ≤20 miles of the treatment facility. Patients with a travel burden >20 miles were more likely to receive a mastectomy (≤20 miles 30.4% vs >20 miles 34.0%, P < .001; odds ratio 1.14, P = .016), and less likely to receive radiation (≤20 miles 63.3% vs >20% miles 60.1%, P < .001; odds ratio 0.81, P < .001). These findings persisted after propensity score matching (n = 33,544 per cohort), with patients living further being more likely to undergo a mastectomy (≤20 miles 30.3% vs >20 miles 35.3%, P < .001) and less likely to receive radiation (≤ 20 miles 65.4% vs. >20 miles 58.5%, P < .001).

CONCLUSION

Patients with hormone receptor-positive stage I to II breast cancer with a larger travel burden are more likely to receive a mastectomy and less likely to undergo radiation therapy to treat their disease.

Neoadjuvant Chemotherapy in Retroperitoneal Sarcoma: A National Cohort Study

INTRODUCTION

Management of retroperitoneal sarcoma (RPS) remains controversial, with the mainstay of treatment being surgery. While neoadjuvant radiation demonstrated no improvement in recurrence-free survival in a prospective randomized trial (STRASS), the role of neoadjuvant chemotherapy (NCT) remains unknown and is the subject of ongoing study (STRASS2).

METHODS

Patients who underwent surgical resection of high-grade RP leiomyosarcoma (LMS) or dedifferentiated liposarcoma (DDLS) were identified from the National Cancer Database (2006-2019). Predictors of NCT were analyzed using univariate and multivariate logistic regression analyses. Differences in 5-year survival were examined using the Kaplan-Meier (KM) method and by Cox proportional hazard modeling.

RESULTS

A total of 2656 patients met inclusion criteria. Fifty-seven percent of patients had DDLS and 43.5% had LMS. Six percent of patients underwent NCT. Patients who received NCT were younger (median age 60 vs 64 years, p < 0.001) and more likely to have LMS (OR 1.4, p = 0.04). In comparing NCT with no-NCT patients, there was no difference in 5-year overall survival (OS) on KM analysis (57.3% vs 52.8%, p = 0.38), nor was any difference seen after propensity matching (54.9% vs 49.1%, p = 0.48, N = 144 per group). When stratified by histology, there was no difference in OS based on receipt of NCT (LMS: 59.8% for NCT group, 56.6% for no-NCT, p = 0.34; DDLS: 54.2% for NCT group, 50.1% for no-NCT, p = 0.99).

CONCLUSION

In patients undergoing surgical resection of RP LMS or DDLS, NCT does not appear to confer an OS advantage. Prospective randomized data from STRASS2 will confirm or refute these retrospective data.

Disparities in Presentation, Treatment, and Survival in Anaplastic Thyroid Cancer

BACKGROUND

Disparities have been previously described in the presentation, management, and outcomes of other thyroid cancer subtypes; however, it is unclear whether such disparities exist in anaplastic thyroid cancer (ATC).

METHODS

We identified patients with ATC from the National Cancer Database (2004-2020). The primary outcomes were receipt of surgery, chemotherapy, and radiation. The secondary outcome was 1-year survival. Multivariable logistic and Cox proportional hazards regressions were used to assess the associations between sex, race/ethnicity, and the outcomes.

RESULTS

Among 5359 patients included, 58% were female, and 80% were non-Hispanic white. Median tumor size was larger in males than females (6.5 vs. 6.0 cm; p < 0.001) and in patients with minority race/ethnicity than in white patients (6.5 vs. 6.0 cm; p < 0.001). After controlling for tumor size and metastatic disease, female patients were more likely to undergo surgical resection (odds ratio [OR]: 1.20; p = 0.016) but less likely to undergo chemotherapy (OR: 0.72; p < 0.001) and radiation (OR: 0.76; p < 0.001) compared with males. Additionally, patients from minority racial/ethnic backgrounds were less likely to undergo chemotherapy (OR: 0.69; p < 0.001) and radiation (OR: 0.71; p < 0.001) than white patients. Overall, unadjusted, 1-year survival was 23%, with differences in treatment receipt accounting for small but significant differences in survival between groups.

CONCLUSIONS

There are disparities in the presentation and treatment of ATC by sex and race/ethnicity that likely reflect differences in access to care as well as patient and provider preferences. While survival is similarly poor across groups, the changing landscape of treatments for ATC warrants efforts to address the potential for exacerbation of disparities.

Neoadjuvant chemotherapy in patients undergoing neoadjuvant radiation for trunk and extremity soft tissue sarcoma

INTRODUCTION

Many patients with high-risk soft tissue sarcoma (STS) develop distant metastases. Meta-analyses suggest that chemotherapy confers a small survival benefit, though few studies focus on neoadjuvant chemotherapy (NCT). There has been more frequent use of neoadjuvant radiation therapy (NRT) in STS, but the utility of NCT for these patients remains unclear.

METHODS

Patients with stage II-III trunk/extremity STS who underwent NRT and resection were identified using the National Cancer Database (2006-2019). Predictors of NCT were analyzed using logistic regression. Change in rate of NCT use over time was assessed using log-linear regression modeling. Survival was examined using Kaplan-Meier (KM) and Cox proportional hazard modeling.

RESULTS

Of 5740 patients, 25% underwent NCT. The overall median age was 62, 55% of patients were male, and 67% had stage III disease. The most common histological subtypes were fibrosarcoma/myxofibrosarcoma (39%) and liposarcoma (16%). Use of NCT decreased by 4.0% per year throughout the study period (p < 0.01). Predictors of NCT included younger age (median 54, IQR 42-64 vs. median 65, IQR 53-75, p < 0.01), treatment at an academic center (odds ratio [OR] 1.5, p < 0.01), and stage III disease (OR 2.2, p < 0.01). Histologic predictors of NCT included synovial sarcoma (52%) and angiosarcoma (45%). With a median follow-up time of 77 months, NCT was associated with improved 5-year survival compared to NRT alone on KM analysis (70% vs. 63%, p < 0.01). This difference persisted on multivariate analysis (hazard ratio 0.86, p = 0.027) and after propensity matching (70% vs. 65%, p = 0.0064).

CONCLUSION

Despite risk of distant failure in high-risk STS, use of NCT has decreased over time in patients receiving NRT. In this retrospective analysis, NCT was associated with a modestly improved overall survival.

Long-term outcomes to neoadjuvant pembrolizumab based on pathological response for patients with resectable stage III/IV cutaneous melanoma

BACKGROUND

While neoadjuvant immunotherapy for melanoma has shown promising results, the data have been limited by a relatively short follow-up time, with most studies reporting 2-year outcomes. The goal of this study was to determine long-term outcomes for stage III/IV melanoma patients treated with neoadjuvant and adjuvant programmed cell death receptor 1 (PD-1) inhibition.

PATIENTS AND METHODS

This is a follow-up study of a previously published phase Ib clinical trial of 30 patients with resectable stage III/IV cutaneous melanoma who received one dose of 200 mg IV neoadjuvant pembrolizumab 3 weeks before surgical resection, followed by 1 year of adjuvant pembrolizumab. The primary outcomes were 5-year overall survival (OS), 5-year recurrence-free survival (RFS), and recurrence patterns.

RESULTS

We report updated results at 5 years of follow-up with a median follow-up of 61.9 months. No deaths occurred in patients with a major pathological response (MPR, <10% viable tumor) or complete pathological response (pCR, no viable tumor) (n = 8), compared to a 5-year OS of 72.8% for the remainder of the cohort (P = 0.12). Two of eight patients with a pCR or MPR had a recurrence. Of the patients with >10% viable tumor remaining, 8 of 22 patients (36%) had a recurrence. Additionally, the median time to recurrence was 3.9 years for patients with ≤10% viable tumor and 0.6 years for patients with >10% viable tumor (P = 0.044).

CONCLUSIONS

The 5-year results from this trial represent the longest follow-up of a single-agent neoadjuvant PD-1 trial to date. Response to neoadjuvant therapy continues to be an important prognosticator with regard to OS and RFS. Additionally, recurrences in patients with pCR occur later and are salvageable, with a 5-year OS of 100%. These results demonstrate the long-term efficacy of single-agent neoadjuvant/adjuvant PD-1 blockade in patients with a pCR and the importance of long-term follow-up for these patients.

TRIAL REGISTRATION

Clinicaltrials.gov, NCT02434354.

Impact of Patient Comorbidities on Presentation Stage of Breast and Colon Cancers

BACKGROUND

While patients with multiple comorbidities may have frequent contact with medical providers, it is unclear whether their healthcare visits translate into earlier detection of cancers, specifically breast and colon cancers.

METHODS

Patients diagnosed with stage I-IV breast ductal carcinoma and colon adenocarcinoma were identified from the National Cancer Database and stratified by comorbidity burden, dichotomized as a Charlson Comorbidity Index (CCI) Score of <2 or ≥2. Characteristics associated with comorbidities were analyzed by univariate and multivariate logistic regression. Propensity-score matching was performed to determine the impact of CCI on stage at cancer diagnosis, dichotomized as early (I-II) or late (III-IV).

RESULTS

A total of 672,032 patients with colon adenocarcinoma and 2,132,889 with breast ductal carcinoma were included. Patients with colon adenocarcinoma who had a CCI ≥ 2 (11%, n = 72,620) were more likely to be diagnosed with early-stage disease (53% vs. 47%; odds ratio [OR] 1.02, p = 0.017), and this finding persisted after propensity matching (CCI ≥ 2 55% vs. CCI < 2 53%, p < 0.001). Patients with breast ductal carcinoma who had a CCI ≥ 2 (4%, n = 85,069) were more likely to be diagnosed with late-stage disease (15% vs. 12%; OR 1.35, p < 0.001). This finding also persisted after propensity matching (CCI ≥ 2 14% vs. CCI < 2 10%, p < 0.001).

CONCLUSIONS

Patients with more comorbidities are more likely to present with early-stage colon cancers but late-stage breast cancers. This finding may reflect differences in practice patterns for routine screening in these patients. Providers should continue guideline directed screenings to detect cancers at an earlier stage and optimize outcomes.

Radiation, Lymph Node Dissection, or Both: Management of Lymph Node Micrometastases from Merkel Cell Carcinoma

BACKGROUND

Regional lymph node micrometastases from Merkel cell carcinoma (MCC) can be treated with completion lymph node dissection (CLND) and/or radiation therapy (RT). It is unclear how these options compare in terms of survival benefits for patients.

PATIENTS AND METHODS

This retrospective cohort study used data from years 2012-2019 of the National Cancer Database. Patients with MCC and clinically negative, but pathologically positive, lymph node metastases who received RT to and/or CLND of the regional lymph node basin were included. Inverse probability weight balancing was performed using covariates followed by Cox proportional hazards modeling for survival analysis.

RESULTS

A total of 962 patients were included [median (interquartile range) age, 74 (67-80) years, 662 (68.8%) male patients, 926 (96.3%) white patients]. The majority (63%, n = 606) had a CLND only, while 18% (n = 173) had RT only, and 19% (n = 183) had both CLND and RT. From 2016 to 2019, usage of RT only increased from 10% to 31.8%. Multivariate analysis demonstrated that treatment modality was not associated with survival [RT versus CLND, hazard ratio (HR) 0.842, 95% confidence interval (CI) 0.621-1.142, p = 0.269, RT+CLND versus CLND, HR 1.029, 95% CI 0.775-1.367, p = 0.844]. This persisted after balancing weights (RT versus CLND, HR 0.837, 95% CI 0.614-1.142, p = 0.262, RT+CLND versus CLND, HR 1.085, 95% CI 0.801-1.470, p = 0.599).

CONCLUSIONS

The usage of RT for nodal micrometastasis in MCC is increasing as compared with CLND. This strategy appears to be safe, with no significant difference in survival outcomes.

Primary Hyperparathyroidism in Young Adult Patients

BACKGROUND

Primary hyperparathyroidism (PHPT) affects 2% of Americans over 55 years of age, and is less common in younger patients. Pediatric PHPT patients have higher rates of multigland disease (MGD). We studied young adult patients to determine whether they have similarly elevated rates of MGD and would benefit from routine bilateral neck exploration.

METHODS

Retrospective chart review was performed on patients who underwent parathyroidectomy for PHPT (2000-2019). Cohorts were defined by age: Group A (18-40 years) and Group B (> 40 years). Univariate and multivariate logistic regression analyses were performed.

RESULTS

Of 3889 patients with PHPT, 9.1% (n = 352) were included in Group A. On multivariate analysis, multiple endocrine neoplasia (odds ratio [OR] 6.3, 95% confidence interval [CI] 3.1-12.7), male sex (OR 1.3, 95% CI 1.0-1.5), family history of PHPT (OR 2.7, 95% CI 1.6-4.8), prior parathyroidectomy (OR 2.2, 95% CI 1.6-3.0), and non-localizing imaging (OR 1.8, 95% CI 1.5-2.1) were associated with MGD; younger age was not an independent risk factor. In patients with sporadic PHPT (n = 3833), family history was most strongly associated with MGD (OR 4.0, 95% CI 2.2-7.3).

CONCLUSIONS

In our population of patients with sporadic PHPT, a positive family history of PHPT was strongly associated with MGD; additional associations were found with prior parathyroidectomy, non-localizing imaging, and male sex. Younger age was not an independent risk factor. Age alone in the absence of a family history should not raise suspicion for MGD nor determine the need for bilateral neck exploration.

Sentinel lymph node biopsy status improves adjuvant therapy decision-making in patients with clinical stage IIB/C melanoma: A population-based analysis

BACKGROUND

Given the results of the recent KEYNOTE-716 trial, the performance of sentinel lymph node (SLN) biopsy for patients with clinical stage IIB/C melanoma has been questioned.

OBJECTIVE

Determine the utility of SLN status in guiding the recommendations for adjuvant therapy.

METHODS

Patients with clinical stage IIB/C cutaneous melanoma who underwent wide local excision and SLN biopsy between 2004 and 2011 were identified from the Surveillance, Epidemiology, and End Results database. Two prognostic models, with and without SLN status, were developed predicting risk of melanoma-specific death (MSD). The primary outcome was net benefit at treatment thresholds of 20% to 40% risk of 5-year MSD.

RESULTS

For the 4391 patients included, the 5-year MSD rate was 46%. The model estimating 5-year MSD risk that included SLN status provided greater net benefit at treatment thresholds from 30% to 78% compared to the model without SLN status. The added net benefit for the SLN biopsy-containing model persisted in subgroup analysis of patients in different age groups and with various T stages.

LIMITATIONS

Retrospective study.

CONCLUSIONS

A prognostic model with SLN status estimating patient risk for 5-year MSD provides superior net benefit compared to a model with primary tumor staging factors alone for threshold mortality rates ≥30%.

Quality and readability assessment of online patient information on cytoreductive surgery and hyperthermic intraperitoneal chemotherapy

BACKGROUND AND OBJECTIVES

We aim to assess the quality and readability of online information available to patients considering cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS-HIPEC).

METHODS

The top three search engines (Google, Bing, and Yahoo) were searched in March 2022. Websites were classified as academic, hospital-affiliated, foundation/advocacy, commercial, or unspecified. Quality of information was assessed using the JAMA benchmark criteria (0-4) and DISCERN tool (16-80), and the presence of a Health On the Net code (HONcode) seal. Readability was evaluated using the Flesch Reading Ease score.

RESULTS

Fifty unique websites were included. The average JAMA and DISCERN scores of all websites were 0.72 ± 1.14 and 39.58 ± 13.71, respectively. Foundation/advocacy websites had significantly higher JAMA mean score than commercial (p = 0.044), academic (p < 0.001), and hospital-affiliated websites (p = 0.001). Foundation/advocacy sites had a significantly higher DISCERN mean score than hospital-affiliated (p = 0.035) and academic websites (p = 0.030). The HONcode seal was present in 4 (8%) websites analyzed. Readability was difficult and at the level of college students.

CONCLUSIONS

The overall quality of patient-oriented online information on CRS-HIPEC is poor and available resources may not be comprehensible to the general public. Patients seeking information on CRS-HIPEC should be directed to sites affiliated with foundation/advocacy organizations.

Clinical Outcomes Associated With Pembrolizumab Monotherapy Among Adults With Diffuse Malignant Peritoneal Mesothelioma

Importance

Diffuse malignant peritoneal mesothelioma (DMPM) represents a rare and clinically distinct entity among malignant mesotheliomas. Pembrolizumab has activity in diffuse pleural mesothelioma but limited data are available for DMPM; thus, DMPM-specific outcome data are needed.

Objective

To evaluate outcomes after the initiation of pembrolizumab monotherapy in the treatment of adults with DMPM.

Design, Setting, and Participants

This retrospective cohort study was conducted in 2 tertiary care academic cancer centers (University of Pennsylvania Hospital Abramson Cancer Center and Memorial Sloan Kettering Cancer Center). All patients with DMPM treated between January 1, 2015, and September 1, 2019, were retrospectively identified and followed until January 1, 2021. Statistical analysis was performed between September 2021 and February 2022.

Exposures

Pembrolizumab (200 mg or 2 mg/kg every 21 days).

Main Outcomes and Measures

Median progression-free survival (PFS) and median overall survival (OS) were assessed using Kaplan-Meier estimates. The best overall response was determined using RECIST (Response Evaluation Criteria in Solid Tumors) criteria, version 1.1. The association of disease characteristics with partial response was evaluated using the Fisher exact test.

Results

This study included 24 patients with DMPM who received pembrolizumab monotherapy. Patients had a median age of 62 years (IQR, 52.4-70.6 years); 14 (58.3%) were women, 18 (75.0%) had epithelioid histology, and most (19 [79.2%]) were White. A total of 23 patients (95.8%) received systemic chemotherapy prior to pembrolizumab, and the median number of lines of prior therapy was 2 (range, 0-6 lines). Of the 17 patients who underwent programmed death ligand 1 (PD-L1) testing, 6 (35.3%) had positive tumor PD-L1 expression (range, 1.0%-80.0%). Of the 19 evaluable patients, 4 (21.0%) had a partial response (overall response rate, 21.1% [95% CI, 6.1%-46.6%]), 10 (52.6%) had stable disease, and 5 (26.3%) had progressive disease (5 of 24 patients [20.8%] were lost to follow-up). There was no association between a partial response and the presence of a BAP1 alteration, PD-L1 positivity, or nonepithelioid histology. With a median follow-up of 29.2 (95% CI, 19.3 to not available [NA]) months, the median PFS was 4.9 (95% CI, 2.8-13.3) months and the median OS was 20.9 (95% CI, 10.0 to NA) months from pembrolizumab initiation. Three patients (12.5%) experienced PFS of more than 2 years. Among patients with nonepithelioid vs epithelioid histology, there was a numeric advantage in median PFS (11.5 [95% CI, 2.8 to NA] vs 4.0 [95% CI, 2.8-8.8] months) and median OS (31.8 [95% CI, 8.3 to NA] vs 17.5 [95% CI, 10.0 to NA] months); however, this did not reach statistical significance.

Conclusions and Relevance

The results of this retrospective dual-center cohort study of patients with DMPM suggest that pembrolizumab had clinical activity regardless of PD-L1 status or histology, although patients with nonepithelioid histology may have experienced additional clinical benefit. The partial response rate of 21.0% and median OS of 20.9 months in this cohort with 75.0% epithelioid histology warrants further investigation to identify those most likely to respond to immunotherapy.

Association Between Metastatic Melanoma Response to Checkpoint Inhibitor Therapy and Tumor-Infiltrating Lymphocyte Classification on Primary Cutaneous Melanoma Biopsies

This cohort study examines the association between tumor-infiltrating lymphocyte classification and disease progression among patients with metastatic primary cutaneous melanoma receiving checkpoint inhibitor therapy.

Trends in infectious complications after partial colectomy for colon cancer over a decade: A national cohort study

BACKGROUND

The American College of Surgeons National Surgical Quality Improvement Program helps participating hospitals track and report surgical complications with the goal of improving patient care. We sought to determine whether postoperative infectious complications after elective colectomy for malignancy improved among participating centers over time.

METHODS

Patients with colon malignancies who underwent elective partial colectomy with primary anastomosis (categorized as low or non-low) were identified from the American College of Surgeons National Surgical Quality Improvement Program database (2011-2019). Thirty-day postoperative infectious complications analyzed by year included superficial, deep, and organ space surgical site infections, urinary tract infection, pneumonia, and sepsis. Trends in patient and treatment characteristics were investigated using log-linear regression along with their association with infectious outcomes.

RESULTS

Of the 78,827 patients identified, 51% were female, and the median age was 68. The majority (84%) underwent partial colectomy without a low anastomosis. There was a decrease in all infectious complications except for organ space infections which increased 35% overall from 2.0 to 2.7% (P = .037), driven by patients without a low anastomosis (1.9%-2.7%, P = .01). There was no change in most patient factors associated with organ space infections, except for a notable increase in American Society of Anesthesiologists class III and IV-V patients over time, both associated with organ space infections (P < .001; P = .002).

CONCLUSION

Infectious complications have decreased significantly overall after colectomy for colon cancer, whereas there has been an increase in organ space infection rates specifically. Although changing patient characteristics may contribute to this observed trend, further study is needed to better understand its etiology to help mitigate this complication.

Shared and distinct biological circuits in effector, memory and exhausted CD8+ T cells revealed by temporal single-cell transcriptomics and epigenetics

Naïve CD8+ T cells can differentiate into effector (Teff), memory (Tmem) or exhausted (Tex) T cells. These developmental pathways are associated with distinct transcriptional and epigenetic changes that endow cells with different functional capacities and therefore therapeutic potential. The molecular circuitry underlying these developmental trajectories and the extent of heterogeneity within Teff, Tmem and Tex populations remain poorly understood. Here, we used the lymphocytic choriomeningitis virus model of acute-resolving and chronic infection to address these gaps by applying longitudinal single-cell RNA-sequencing (scRNA-seq) and single-cell assay for transposase-accessible chromatin sequencing (scATAC-seq) analyses. These analyses uncovered new subsets, including a subpopulation of Tex cells expressing natural killer cell-associated genes that is dependent on the transcription factor Zeb2, as well as multiple distinct TCF-1+ stem/progenitor-like subsets in acute and chronic infection. These data also revealed insights into the reshaping of Tex subsets following programmed death 1 (PD-1) pathway blockade and identified a key role for the cell stress regulator, Btg1, in establishing the Tex population. Finally, these results highlighted how the same biological circuits such as cytotoxicity or stem/progenitor pathways can be used by CD8+ T cell subsets with highly divergent underlying chromatin landscapes generated during different infections.

Peroxynitrite in the tumor microenvironment changes the profile of antigens allowing escape from cancer immunotherapy

Cancer immunotherapy often depends on recognition of peptide epitopes by cytotoxic T lymphocytes (CTLs). The tumor microenvironment (TME) is enriched for peroxynitrite (PNT), a potent oxidant produced by infiltrating myeloid cells and some tumor cells. We demonstrate that PNT alters the profile of MHC class I bound peptides presented on tumor cells. Only CTLs specific for PNT-resistant peptides have a strong antitumor effect in vivo, whereas CTLs specific for PNT-sensitive peptides are not effective. Therapeutic targeting of PNT in mice reduces resistance of tumor cells to CTLs. Melanoma patients with low PNT activity in their tumors demonstrate a better clinical response to immunotherapy than patients with high PNT activity. Our data suggest that intratumoral PNT activity should be considered for the design of neoantigen-based therapy and also may be an important immunotherapeutic target.

National Practice Patterns in the Management of the Regional Lymph Node Basin After Positive Sentinel Lymph Node Biopsy for Cutaneous Melanoma

BACKGROUND

Immediate completion lymph node dissection (CLND) for patients with sentinel lymph node (SLN) metastasis from cutaneous melanoma has been replaced largely by ultrasound nodal surveillance since the publication of two landmark trials in 2016 and 2017. National practice patterns of CLND remain poorly characterized.

METHODS

Patients with a diagnosis of cutaneous melanoma in 2016 and 2018 without clinical nodal disease who underwent sentinel lymph node biopsy (SLNB) were identified from the National Cancer Database (NCDB). Characteristics associated with CLND were analyzed by uni- and multivariate logistic regression. Overall survival (OS) was estimated using Kaplan-Meier and Cox proportional hazards regression analyses.

RESULTS

Of the 3517 patients included in the study, 1405 had disease diagnosed in 2016. The patients with cutaneous melanoma diagnosed in 2016 had a median age of 60 years and a tumor thickness of 2.3 mm compared to 62 years and 2.4 mm, respectively, for the patients with cutaneous melanoma diagnosed in 2018. According to the NCDB, 40 % (n = 559) of the patients underwent CLND in 2016 compared with 6 % (n = 132) in 2018. The factors associated with receipt of CLND in 2018 included younger age (odds ratio [OR], 0.97; 95 % confidence interval [CI], 0.95-0.99; p = 0.001), rural residence (OR, 3.96; 95 % CI, 1.50-10.49; p = 0.006), head/neck tumor location (OR, 1.88; 95 % CI, 1.10-3.23; p = 0.021), and more than one positive SLN (OR, 1.80; 95 % CI, 1.17-2.76; p = 0.007). The 5-year OS did not differ between the patients who received SLNB only and those who underwent CLND (hazard ratio [HR], 0.93; p = 0.54).

CONCLUSION

The rates of CLND have decreased nationally. However, patients with head/neck primary tumors who live in rural locations are more likely to undergo CLND, highlighting populations for which treatment may be non-uniform with national practice patterns.

Impact of the affordable care act's medicaid expansion on presentation stage and perioperative outcomes of colorectal cancer

BACKGROUND AND OBJECTIVES

Medicaid expansion has improved healthcare coverage and preventive health service use. To what extent this has resulted in earlier stage colorectal cancer diagnoses and impacted perioperative outcomes is unclear.

METHODS

This was a retrospective difference-in-difference study using the National Cancer Database on adults (40-64) with Medicaid or no insurance, diagnosed with colorectal adenocarcinomas before (2010-2013) and after (2015-2018) expansion. The primary outcome was early-stage (American Joint Committee on Cancer Stage 0-1) diagnosis. The secondary outcomes were rate of local excision, emergency surgery, postoperative length of stay, rates of minimally invasive surgery, postoperative mortality, and overall survival (OS).

RESULTS

Medicaid expansion was associated with an increase in early-stage diagnoses for patients with colorectal cancers (odds ratio [OR]: 1.28, 95% confidence interval [CI]: 1.15-1.43), an increase in local excision (OR: 1.39, 95% CI: 1.13-1.69), and a decreased rate of emergent surgery (OR: 0.85, 95% CI: 0.75-0.97) and 90-day mortality (OR: 0.75, 95% CI: 0.59-0.97). Additionally, patients in expansion states postexpansion had an improved 5-year OS (hazard ratio: 0.88, 95% CI: 0.83-0.94).

CONCLUSIONS

Insurance coverage expansion may be particularly important for optimizing stage of diagnosis, subsequent survival, and perioperative outcomes for socioeconomically vulnerable patients.

Fourteen years of pancreatic surgery for malignancy among ACS-NSQIP centers: Trends in major morbidity and mortality

BACKGROUND

The American College of Surgeons National Surgical Quality Improvement Program was established to help participating hospitals track and report surgical complications with the goal of improving surgical care. We sought to determine whether this has led to improvements in surgical outcomes for pancreatic malignancies.

METHODS

Patients with pancreatic malignancies who underwent surgical resection were identified from the American College of Surgeons National Surgical Quality Improvement Program database (2006-2019). Thirty-day postoperative major morbidity and mortality were analyzed by year. Major morbidity included organ and deep surgical site infection, venous thromboembolism, cardiac event, pneumonia, acute renal failure, sepsis, and respiratory failure.

RESULTS

Of the 28,888 patients identified, 51% were male, the median age was 68, 74.3% underwent a pancreaticoduodenectomy, and 25.7% underwent a distal pancreatectomy. Among patients who underwent a pancreaticoduodenectomy, there was a significant increase in major morbidity (annual percent change 0.77, P = .012) driven by increases in organ space surgical site infection (annual percent change 3.52, P < .001) and venous thromboembolism (annual percent change 4.72, P = .005). However, there was a decrease in postoperative mortality (annual percent change -4.58, P = .001). For distal pancreatectomy patients, there was no change in rates of overall major morbidity (annual percent change -1.35, P = .08) or mortality (annual percent change -3.21, P = .25).

CONCLUSION

Although major morbidity and mortality have not significantly changed for distal pancreatectomy patients, mortality has steadily decreased for patients undergoing pancreaticoduodenectomy, despite an increase in major morbidity. Whether this trend reflects a change in patient selection, an increase in detection of postoperative morbidities and/or an improvement in mitigation of these morbidities warrants further study.

Association of type II diabetes mellitus with characteristics and outcomes for patients undergoing sentinel lymph node biopsy for cutaneous melanoma

BACKGROUND AND OBJECTIVES

Type II diabetes mellitus (T2DM) can lead to an immunosuppressed state, but whether T2DM is associated with worse outcomes for patients with melanoma has not been well studied.

METHODS

Consecutive patients diagnosed with clinical stage I-II cutaneous melanoma who underwent sentinel lymph node biopsy at a single institution (2007-2016) were identified. Melanoma characteristics and recurrence/survival outcomes were compared between patients with and without T2DM at the time of melanoma diagnosis.

RESULTS

Of 1128 patients evaluated, 111 (9.8%) had T2DM (n = 94 [84.7%] non-insulin dependent [NID-T2DM]; n = 17 [15.3%] insulin dependent [ID-T2DM]). T2DM patients were more likely to be older (odds ratio [OR] 1.04, p < 0.001), male (OR 2.15, p = 0.003), have tumors >1.0 mm (OR 1.88, p = 0.023), and have microsatellitosis (OR 2.29, p = 0.030). Five-year cumulative incidence of melanoma recurrence was significantly higher for patients with ID-T2DM (46.7% ID-T2DM vs. 25.7% NID-T2DM vs. 17.1% no T2DM, p < 0.001), and on multivariable analysis, ID-T2DM was independently associated with melanoma recurrence (hazard ratio 2.57, p = 0.015). No difference in 5-year disease-specific survival was observed between groups.

CONCLUSIONS

ID-T2DM appears to be associated with more advanced melanoma and increased risk for melanoma recurrence. Further study as to whether this reflects differences in tumor biology or host factors is warranted.

An Internally Validated Prognostic Risk-Score Model for Disease-Specific Survival in Clinical Stage I and II Merkel Cell Carcinoma

BACKGROUND

Merkel cell carcinoma (MCC) is a rare cutaneous malignancy for which factors predictive of disease-specific survival (DSS) are poorly defined.

METHODS

Patients from six centers (2005-2020) with clinical stage I-II MCC who underwent sentinel lymph node (SLN) biopsy were included. Factors associated with DSS were identified using competing-risks regression analysis. Risk-score modeling was established using competing-risks regression on a training dataset and internally validated by point assignment to variables.

RESULTS

Of 604 patients, 474 (78.5%) and 128 (21.2%) patients had clinical stage I and II disease, respectively, and 189 (31.3%) had SLN metastases. The 5-year DSS rate was 81.8% with a median follow-up of 31 months. Prognostic factors associated with worse DSS included increasing age (hazard ratio [HR] 1.03, p = 0.046), male sex (HR 3.21, p = 0.021), immune compromise (HR 2.46, p = 0.013), presence of microsatellites (HR 2.65, p = 0.041), and regional nodal involvement (1 node: HR 2.48, p = 0.039; ≥2 nodes: HR 2.95, p = 0.026). An internally validated, risk-score model incorporating all of these factors was developed with good performance (AUC 0.738). Patients with ≤ 4.00 and > 4.00 points had 5-year DSS rates of 89.4% and 67.2%, respectively. Five-year DSS for pathologic stage I/II patients with > 4.00 points (n = 49) was 79.8% and for pathologic stage III patients with ≤ 4.00 points (n = 62) was 90.3%.

CONCLUSIONS

A risk-score model, including patient and tumor factors, based on DSS improves prognostic assessment of patients with clinically localized MCC. This may inform surveillance strategies and patient selection for adjuvant therapy trials.

Educational Review: Neoadjuvant Approaches to Melanoma

BACKGROUND

With the development of novel systemic therapies, the treatment of patients with melanoma has changed drastically over the past few years, especially with regard to neoadjuvant treatments. Standard of care for patients with resectable stage III/IV melanoma traditionally consisted of surgery, with possible adjuvant treatment. However, there have been promising improvements in patient outcomes with neoadjuvant treatment compared to upfront surgery, specifically with targeted and immune therapies.

METHODS

A review of clinical trials in the neoadjuvant treatment of stage III/IV melanoma was performed.

RESULTS

Multiple phase I-II clinical trials have investigated the utility of interferon, targeted therapies (i.e., BRAF and/or MEK inhibitors) and immune checkpoint inhibitors (i.e., PD-1 or CTLA-4 inhibitors) in the treatment of resectable clinical stage III/IV melanoma. Large strides have been made with regards to optimal treatment strategy and dosing, to maximize clinical and pathologic response rates while minimizing toxicities. Additionally, complete pathologic response to neoadjuvant therapies translates to a disease-free survival benefit. Current and future directions include individualizing surgical and adjuvant therapy based on patient response to neoadjuvant treatments.

CONCLUSIONS

The current evidence, represented by small phase I-II trials, demonstrates advantages to neoadjuvant treatment with targeted or immune therapy for patients with resectable stage III/IV melanoma. Future research is needed to determine the advantages of neoadjuvant compared to adjuvant treatment, and to further refine treatment strategies based on patient response.

HRS phosphorylation drives immunosuppressive exosome secretion and restricts CD8+ T-cell infiltration into tumors

The lack of tumor infiltration by CD8⁺ T cells is associated with poor patient response to anti-PD-1 therapy. Understanding how tumor infiltration is regulated is key to improving treatment efficacy. Here, we report that phosphorylation of HRS, a pivotal component of the ESCRT complex involved in exosome biogenesis, restricts tumor infiltration of cytolytic CD8⁺ T cells. Following ERK-mediated phosphorylation, HRS interacts with and mediates the selective loading of PD-L1 to exosomes, which inhibits the migration of CD8⁺ T cells into tumors. In tissue samples from patients with melanoma, CD8⁺ T cells are excluded from the regions where tumor cells contain high levels of phosphorylated HRS. In murine tumor models, overexpression of phosphorylated HRS increases resistance to anti-PD-1 treatment, whereas inhibition of HRS phosphorylation enhances treatment efficacy. Our study reveals a mechanism by which phosphorylation of HRS in tumor cells regulates anti-tumor immunity by inducing PD-L1⁺ immunosuppressive exosomes, and suggests HRS phosphorylation blockade as a potential strategy to improve the efficacy of cancer immunotherapy.