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.

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.

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.

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.

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 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.

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.

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.