Clinical and Histological Response to Talimogene Laherparepvec Therapy in Advanced Melanoma: Impact on Overall Survival

BACKGROUND

Talimogene laherparepvec (T-VEC) is an FDA-approved oncolytic herpesvirus therapy used for unresectable stage IIIB through IV metastatic melanoma. However, the correlation between clinical complete response (cCR) and pathologic complete response (pCR) in patients treated with T-VEC is understudied.

STUDY DESIGN

We conducted a retrospective study from a prospectively maintained IRB-approved melanoma single-center database in patients treated with T-VEC from October 2015 to April 2022. Patients were categorized into 3 groups: cCR with pCR, cCR without pCR, and less than cCR. The primary endpoint was overall survival. We used descriptive statistics, chi-square tests, and Wilcoxon rank-sum tests to compare key covariates among exposure groups. We used survival analysis to compare survival curves and reported hazard ratio of death (95% CI) across exposure groups.

RESULTS

We included 116 patients with a median overall survival (interquartile range) of 22.7 (14.8-39.3) months. The majority were men (69%) and White (97.4%), with a median age of 74.5 years. More than half of patients (n = 60, 51.6%) achieved cCR. Distribution among the groups was as follows: cCR with pCR (35.3%), cCR without pCR (16.3%), and less than cCR (48.4%). Median overall survival time (interquartile range) was 26.5 (18.6-36.0) months for cCR with pCR, 22.7 (14.4-35.5) months for cCR without pCR, and 17.8 (9.2-47.0) months for less than cCR (log-rank p value = 0.0033).

CONCLUSIONS

Patients achieving cCR with pCR after T-VEC therapy have the most favorable overall survival outcomes, whereas those achieving cCR without pCR have inferior survival and those achieving less than cCR have the poorest overall survival outcomes. These findings emphasize the importance of histological confirmation and provide insights for optimizing T-VEC therapy in patients with advanced melanoma.

Lymph node metastases in young patients with gastrointestinal stromal tumor: A nationwide analysis

BACKGROUND

Children, adolescents, and young adults (CAYA) (age ≤39 years) with GIST have high rates of LNM, but their clinical relevance is undefined. This study analyzed the impact of LNM on overall survival (OS) for CAYA with GIST.

METHODS

The National Cancer Database was queried for patients with resected GIST and pathologic nodal staging data from 2004-2019. Factors associated with LNM were identified. Survival was assessed stratified by presence of LNM.

RESULTS

Of 4420 patients with GIST, 238 were CAYA (5.4%). When compared to older adults, CAYA more often had small intestine primaries (51.8% vs. 36.6%, p < 0.0001), T4 tumors (30.7% vs. 24.5%, p = 0.0275) and pN1 disease (11.3% vs. 4.7%, p < 0.0001). Within a multivariable Cox proportional hazards regression model adjusting for age, comorbid disease, mitotic rate, tumor size, and primary site, LNM were associated with increased hazard of death for older adults (hazard ratio [HR]: 1.83; confidence interval [CI]: 1.35-2.42; p < 0.0001), but not CAYA (HR: 3.38; CI: 0.50-14.08; p = 0.13). For CAYA, only high mitotic rate predicted mortality (HR: 4.68; CI: 1.41-18.37: p = 0.02).

CONCLUSIONS

LNM are more commonly identified among CAYA with resected GIST who undergo lymph node evaluations, but do not appear to impact OS as observed in older adults. High mitotic rate remains a predictor of poor outcomes for CAYA with GIST.

Does Preoperative MRI Reduce Positive Margins after Breast-Conserving Surgery?

BACKGROUND

Breast-conserving surgery (BCS) is a mainstay for breast cancer management, and obtaining negative margins is critical. Some have advocated for the use of preoperative magnetic resonance imaging (MRI) in reducing positive margins after BCS. We sought to determine whether preoperative MRI was associated with reduced positive margins.

PATIENTS AND METHODS

The SHAVE/SHAVE2 trials were multicenter trials in ten US centers with patients with stage 0-3 breast cancer undergoing BCS. Use of preoperative MRI was at the discretion of the surgeon. We evaluated whether or not preoperative MRI was associated with margin status prior to randomization regarding resection of cavity with shave margins.

RESULTS

A total of 631 patients participated. Median age was 64 (range 29-94) years, with a median tumor size of 1.3 cm (range 0.1-9.3 cm). Patient factors included 26.1% of patients (165) had palpable tumors, and 6.5% (41) received neoadjuvant chemotherapy. Tumor factors were notable for invasive lobular histology in 7.0% (44) and extensive intraductal component (EIC) in 32.8% (207). A preoperative MRI was performed in 193 (30.6%) patients. Those who underwent preoperative MRI were less likely to have a positive margin (31.1% versus 38.8%), although this difference was not statistically significant (p = 0.073). On multivariate analysis, controlling for patient and tumor factors, utilization of preoperative MRI was not a significant factor in predicting margin status (p = 0.110). Rather, age (p = 0.032) and tumor size (p = 0.040) were the only factors associated with margin status.

CONCLUSION

These data suggest that preoperative MRI is not associated margin status; rather, patient age and tumor size are the associated factors.

Association of functional, inherited vitamin D-binding protein variants with melanoma-specific death

BACKGROUND

It is unclear whether genetic variants affecting vitamin D metabolism are associated with melanoma prognosis. Two functional missense variants in the vitamin D-binding protein gene (GC), rs7041 and rs4588, determine 3 common haplotypes, Gc1s, Gc1f, and Gc2, of which Gc1f may be associated with decreased all-cause death among melanoma patients based on results of a prior study, but the association of Gc1f with melanoma-specific death is unclear.

METHODS

We investigated the association of the Gc1s, Gc1f, and Gc2 haplotypes with melanoma-specific and all-cause death among 4490 individuals with incident, invasive primary melanoma in 2 population-based studies using multivariable Cox-proportional hazards regression.

RESULTS

In the pooled analysis of both datasets, the patients with the Gc1f haplotype had a 37% lower risk of melanoma-specific death than the patients without Gc1f (hazard ratio [HR] = 0.63, 95% confidence interval [CI] = 0.47 to 0.83, P = .001), with adjustments for age, sex, study center, first- or higher-order primary melanoma, tumor site, pigmentary phenotypes, and Breslow thickness. Associations were similar in both studies. In pooled analyses stratified by Breslow thickness, the corresponding melanoma-specific death HRs for those patients with the Gc1f haplotype compared with those without Gc1f were 0.89 (95% CI = 0.63 to 1.27) among participants with tumor Breslow thickness equal to or less than 2.0 mm and 0.40 (95% CI = 0.25 to 0.63) among participants with tumor Breslow thickness greater than 2.0 mm (Pinteraction = .003).

CONCLUSIONS

Our findings suggest that individuals with the GC haplotype Gc1f may have a lower risk of dying from melanoma-specifically from thicker, higher-risk melanoma-than individuals without this Gc1f haplotype.

International Center-Level Variation in Utilization of Completion Lymph Node Dissection and Adjuvant Systemic Therapy for Sentinel Lymph Node-Positive Melanoma at Major Referral Centers

OBJECTIVE

The aim of this study was to determine overall trends and center-level variation in utilization of completion lymph node dissection (CLND) and adjuvant systemic therapy for sentinel lymph node (SLN)-positive melanoma.

SUMMARY BACKGROUND DATA

Based on recent clinical trials, management options for SLN-positive melanoma now include effective adjuvant systemic therapy and nodal observation instead of CLND. It is unknown how these findings have shaped practice or how these contemporaneous developments have influenced their respective utilization.

METHODS

We performed an international cohort study at 21 melanoma referral centers in Australia, Europe, and the United States that treated adults with SLN-positive melanoma and negative distant staging from July 2017 to June 2019. We used generalized linear and multinomial logistic regression models with random intercepts for each center to assess center-level variation in CLND and adjuvant systemic treatment, adjusting for patient and disease-specific characteristics.

RESULTS

Among 1109 patients, performance of CLND decreased from 28% to 8% and adjuvant systemic therapy use increased from 29 to 60%. For both CLND and adjuvant systemic treatment, the most influential factors were nodal tumor size, stage, and location of treating center. There was notable variation among treating centers in management of stage IIIA patients and use of CLND with adjuvant systemic therapy versus nodal observation alone for similar risk patients.

CONCLUSIONS

There has been an overall decline in CLND and simultaneous adoption of adjuvant systemic therapy for patients with SLN-positive melanoma though wide variation in practice remains. Accounting for differences in patient mix, location of care contributed significantly to the observed variation.

Methylation of nonessential genes in cutaneous melanoma - Rule Out hypothesis

Differential methylation plays an important role in melanoma development and is associated with survival, progression and response to treatment. However, the mechanisms by which methylation promotes melanoma development are poorly understood. The traditional explanation of selective advantage provided by differential methylation postulates that hypermethylation of regulatory 5'-cytosine-phosphate-guanine-3' dinucleotides (CpGs) downregulates the expression of tumor suppressor genes and therefore promotes tumorigenesis. We believe that other (not necessarily alternative) explanations of the selective advantages of methylation are also possible. Here, we hypothesize that melanoma cells use methylation to shut down transcription of nonessential genes - those not required for cell survival and proliferation. Suppression of nonessential genes allows tumor cells to be more efficient in terms of energy and resource usage, providing them with a selective advantage over the tumor cells that transcribe and subsequently translate genes they do not need. We named the hypothesis the Rule Out (RO) hypothesis. The RO hypothesis predicts higher methylation of CpGs located in regulatory regions (CpG islands) of nonessential genes. It also predicts the higher methylation of regulatory CpGs linked to nonessential genes in melanomas compared to nevi and lower expression of nonessential genes in malignant (derived from melanoma) versus normal (derived from nonaffected skin) melanocytes. The analyses conducted using in-house and publicly available data found that all predictions derived from the RO hypothesis hold, providing observational support for the hypothesis.

Increased tryptophan, but not increased glucose metabolism, predict resistance of pembrolizumab in stage III/IV melanoma

Clinical trials of combined IDO/PD1 blockade in metastatic melanoma (MM) failed to show additional clinical benefit compared to PD1-alone inhibition. We reasoned that a tryptophan-metabolizing pathway other than the kynurenine one is essential. We immunohistochemically stained tissues along the nevus-to-MM progression pathway for tryptophan-metabolizing enzymes (TMEs; TPH1, TPH2, TDO2, IDO1) and the tryptophan transporter, LAT1. We assessed tryptophan and glucose metabolism by performing baseline C11-labeled α-methyl tryptophan (C11-AMT) and fluorodeoxyglucose (FDG) PET imaging of tumor lesions in a prospective clinical trial of pembrolizumab in MM (clinicaltrials.gov, NCT03089606). We found higher protein expression of all TMEs and LAT1 in melanoma cells than tumor-infiltrating lymphocytes (TILs) within MM tumors (n = 68). Melanoma cell-specific TPH1 and LAT1 expressions were significantly anti-correlated with TIL presence in MM. High melanoma cell-specific LAT1 and low IDO1 expression were associated with worse overall survival (OS) in MM. Exploratory optimal cutpoint survival analysis of pretreatment 'high' vs. 'low' C11-AMT SUV_max of the hottest tumor lesion per patient revealed that the 'low' C11-AMT SUV_max was associated with longer progression-free survival in our clinical trial (n = 26). We saw no such trends with pretreatment FDG PET SUV_max. Treatment of melanoma cell lines with telotristat, a TPH1 inhibitor, increased IDO expression and kynurenine production in addition to suppression of serotonin production. High melanoma tryptophan metabolism is a poor predictor of pembrolizumab response and an adverse prognostic factor. Serotoninergic but not kynurenine pathway activation may be significant. Melanoma cells outcompete adjacent TILs, eventually depriving the latter of an essential amino acid.

InterMEL: An international biorepository and clinical database to uncover predictors of survival in early-stage melanoma

INTRODUCTION

We are conducting a multicenter study to identify classifiers predictive of disease-specific survival in patients with primary melanomas. Here we delineate the unique aspects, challenges, and best practices for optimizing a study of generally small-sized pigmented tumor samples including primary melanomas of at least 1.05mm from AJTCC TNM stage IIA-IIID patients. We also evaluated tissue-derived predictors of extracted nucleic acids' quality and success in downstream testing. This ongoing study will target 1,000 melanomas within the international InterMEL consortium.

METHODS

Following a pre-established protocol, participating centers ship formalin-fixed paraffin embedded (FFPE) tissue sections to Memorial Sloan Kettering Cancer Center for the centralized handling, dermatopathology review and histology-guided coextraction of RNA and DNA. Samples are distributed for evaluation of somatic mutations using next gen sequencing (NGS) with the MSK-IMPACTTM assay, methylation-profiling (Infinium MethylationEPIC arrays), and miRNA expression (Nanostring nCounter Human v3 miRNA Expression Assay).

RESULTS

Sufficient material was obtained for screening of miRNA expression in 683/685 (99%) eligible melanomas, methylation in 467 (68%), and somatic mutations in 560 (82%). In 446/685 (65%) cases, aliquots of RNA/DNA were sufficient for testing with all three platforms. Among samples evaluated by the time of this analysis, the mean NGS coverage was 249x, 59 (18.6%) samples had coverage below 100x, and 41/414 (10%) failed methylation QC due to low intensity probes or insufficient Meta-Mixed Interquartile (BMIQ)- and single sample (ss)- Noob normalizations. Six of 683 RNAs (1%) failed Nanostring QC due to the low proportion of probes above the minimum threshold. Age of the FFPE tissue blocks (p<0.001) and time elapsed from sectioning to co-extraction (p = 0.002) were associated with methylation screening failures. Melanin reduced the ability to amplify fragments of 200bp or greater (absent/lightly pigmented vs heavily pigmented, p<0.003). Conversely, heavily pigmented tumors rendered greater amounts of RNA (p<0.001), and of RNA above 200 nucleotides (p<0.001).

CONCLUSION

Our experience with many archival tissues demonstrates that with careful management of tissue processing and quality control it is possible to conduct multi-omic studies in a complex multi-institutional setting for investigations involving minute quantities of FFPE tumors, as in studies of early-stage melanoma. The study describes, for the first time, the optimal strategy for obtaining archival and limited tumor tissue, the characteristics of the nucleic acids co-extracted from a unique cell lysate, and success rate in downstream applications. In addition, our findings provide an estimate of the anticipated attrition that will guide other large multicenter research and consortia.

Outcomes with adjuvant anti-PD-1 therapy in patients with sentinel lymph node-positive melanoma without completion lymph node dissection

Until recently, most patients with sentinel lymph node-positive (SLN+) melanoma underwent a completion lymph node dissection (CLND), as mandated in published trials of adjuvant systemic therapies. Following multicenter selective lymphadenectomy trial-II, most patients with SLN+ melanoma no longer undergo a CLND prior to adjuvant systemic therapy. A retrospective analysis of clinical outcomes in SLN+ melanoma patients treated with adjuvant systemic therapy after July 2017 was performed in 21 international cancer centers. Of 462 patients who received systemic adjuvant therapy, 326 patients received adjuvant anti-PD-1 without prior immediate (IM) CLND, while 60 underwent IM CLND. With median follow-up of 21 months, 24-month relapse-free survival (RFS) was 67% (95% CI 62% to 73%) in the 326 patients. When the patient subgroups who would have been eligible for the two adjuvant anti-PD-1 clinical trials mandating IM CLND were analyzed separately, 24-month RFS rates were 64%, very similar to the RFS rates from those studies. Of these no-CLND patients, those with SLN tumor deposit >1 mm, stage IIIC/D and ulcerated primary had worse RFS. Of the patients who relapsed on adjuvant anti-PD-1, those without IM CLND had a higher rate of relapse in the regional nodal basin than those with IM CLND (46% vs 11%). Therefore, 55% of patients who relapsed without prior CLND underwent surgery including therapeutic lymph node dissection (TLND), with 30% relapsing a second time; there was no difference in subsequent relapse between patients who received observation vs secondary adjuvant therapy. Despite the increased frequency of nodal relapses, adjuvant anti-PD-1 therapy may be as effective in SLN+ pts who forego IM CLND and salvage surgery with TLND at relapse may be a viable option for these patients.

Omission of Radiation in Conservative Treatment for Breast Cancer: Opportunity for De-escalation of Care

INTRODUCTION

De-escalation of breast cancer treatment aims to reduce patient and financial toxicity without compromising outcomes. Level I evidence and National Comprehensive Cancer Network guidelines support omission of adjuvant radiation in patients aged >70 y with hormone-sensitive, pT1N0M0 invasive breast cancer treated with endocrine therapy. We evaluated radiation use in patients eligible for guideline concordant omission of radiation.

METHODS

Subgroup analysis of patients eligible for radiation omission from two pooled randomized controlled trials, which included stage 0-III breast cancer patients undergoing breast conserving surgery, was performed to evaluate factors associated with radiation use.

RESULTS

Of 631 patients, 47 (7.4%) met radiation omission criteria and were treated by 14 surgeons at eight institutions. The mean age was 75.3 (standard deviation + 4.4) y. Majority of patients identified as White (n = 46; 97.9%) and non-Hispanic (n = 44; 93.6%). The mean tumor size was 1.0 cm; 37 patients (88.1%) had ductal, 4 patients (9.5%) had lobular, and 17 patients (40.5%) had low-grade disease. Among patients eligible for radiation omission, 34 (72.3%) patients received adjuvant radiation. Those who received radiation were significantly younger than those who did not (74 y, interquartile range = 4 y, versus 78 y, interquartile range = 11 y, P = 0.03). There was no difference in radiation use based on size (P = 0.4), histology (P = 0.5), grade (P = 0.7), race (P = 1), ethnicity (P = 0.6), institution (P = 0.1), gender of the surgeon (P = 0.7), or surgeon (P = 0.1).

CONCLUSIONS

Fewer than 10% of patients undergoing breast conservation met criteria for radiation omission. Nearly three-quarters received radiation therapy with younger age being a driver of radiation use, suggesting ample opportunity for de-escalation, particularly among younger eligible patients.

Characterization of the CpG Island Hypermethylated Phenotype Subclass in Primary Melanomas

Cutaneous melanoma can be lethal even if detected at an early stage. Epigenetic profiling may facilitate the identification of aggressive primary melanomas with unfavorable outcomes. We performed clustering of whole-genome methylation data to identify subclasses that were then assessed for survival, clinical features, methylation patterns, and biological pathways. Among 89 cutaneous primary invasive melanomas, we identified three methylation subclasses exhibiting low methylation, intermediate methylation, or hypermethylation of CpG islands, known as the CpG island methylator phenotype (CIMP). CIMP melanomas occurred as early as tumor stage 1b and, compared with low-methylation melanomas, were associated with age at diagnosis ≥65 years, lentigo maligna melanoma histologic subtype, presence of ulceration, higher American Joint Committee on Cancer stage and tumor stage, and lower tumor-infiltrating lymphocyte grade (all P < 0.05). Patients with CIMP melanomas had worse melanoma-specific survival (hazard ratio = 11.84; confidence interval = 4.65‒30.20) than those with low-methylation melanomas, adjusted for age, sex, American Joint Committee on Cancer stage, and tumor-infiltrating lymphocyte grade. Genes hypermethylated in CIMP compared with those in low-methylation melanomas included PTEN, VDR, PD-L1, TET2, and gene sets related to development/differentiation, the extracellular matrix, and immunity. CIMP melanomas exhibited hypermethylation of genes important in melanoma progression and tumor immunity, and although present in some early melanomas, CIMP was associated with worse survival independent of known prognostic factors.

The efficacy of immune checkpoint blockade for melanoma in-transit with or without nodal metastases - A multicenter cohort study

PURPOSE

Guidelines addressing melanoma in-transit metastasis (ITM) recommend immune checkpoint inhibitors (ICI) as a first-line treatment option, despite the fact that there are no efficacy data available from prospective trials for exclusively ITM disease. The study aims to analyze the outcome of patients with ITM treated with ICI based on data from a large cohort of patients treated at international referral clinics.

METHODS

A multicenter retrospective cohort study of patients treated between January 2015 and December 2020 from Australia, Europe, and the USA, evaluating treatment with ICI for ITM with or without nodal involvement (AJCC8 N1c, N2c, and N3c) and without distant disease (M0). Treatment was with PD-1 inhibitor (nivolumab or pembrolizumab) and/or CTLA-4 inhibitor (ipilimumab). The response was evaluated according to the RECIST criteria modified for cutaneous lesions.

RESULTS

A total of 287 patients from 21 institutions in eight countries were included. Immunotherapy was first-line treatment in 64 (22%) patients. PD-1 or CTLA-4 inhibitor monotherapy was given in 233 (81%) and 23 (8%) patients, respectively, while 31 (11%) received both in combination. The overall response rate was 56%, complete response (CR) rate was 36%, and progressive disease (PD) rate was 32%. Median PFS was ten months (95% CI 7.4-12.6 months) with a one-, two-, and five-year PFS rate of 48%, 33%, and 18%, respectively. Median MSS was not reached, and the one-, two-, and five-year MSS rates were 95%, 83%, and 71%, respectively.

CONCLUSION

Systemic immunotherapy is an effective treatment for melanoma ITM. Future studies should evaluate the role of systemic immunotherapy in the context of multimodality therapy, including locoregional treatments such as surgery, intralesional therapy, and regional therapies.

Pathologic complete response and survival after neoadjuvant chemotherapy in cT1-T2/N0 HER2+ breast cancer

Women with small HER2+ breast cancers may have excellent prognosis with adjuvant single-agent chemotherapy and HER2-targeted therapy. The role of de-escalated therapy in the neoadjuvant setting, however, remains uncertain. We conducted a cohort study of adult women with T1-2/cN0 HER2+ breast cancer diagnosed 2013–2016 in the National Cancer Database treated with neoadjuvant chemotherapy (NAC) and HER2-targeted therapy. Factors associated with pathologic complete response (pCR) and overall survival were examined. In total, 6994 patients were included, 32% cT1 and 68% cT2. Multi-agent NAC was given to 90% of women while single-agent NAC was given to 10% of women. pCR was achieved in 46% of cT2 patients and 43% of cT1, and in 46% of patients treated with multi-agent versus 38% single agent. Patients receiving multi-agent chemotherapy were younger, had fewer comorbidities, and had higher cT stage and grade. In all patients, pCR was associated with improved survival (p < 0.01). Multi-agent chemotherapy (OR 1.3, p = 0.003), hormone receptor negative (OR 2.6, p < 0.001), higher grade (OR 2.2, p < 0.001), younger age (OR 1.4, p = 0.011), and later year of diagnosis (OR 1.3, p = 0.005) were associated with achieving pCR. Multi-agent chemotherapy was associated with higher likelihood of pCR, but this effect was modest compared to other factors. Single-agent NAC with HER2-directed therapy in selected patients may provide excellent outcome with reduced toxicity, while allowing escalated therapy in the adjuvant setting for patients with residual disease. Prospective studies are needed to determine effects of de-escalation in the neoadjuvant setting on survival and optimal selection strategies.

Sociodemographic and Clinical Predictors of Neoadjuvant Chemotherapy in cT1-T2/N0 HER2-Amplified Breast Cancer

BACKGROUND

The optimal treatment strategy for small node-negative human epidermal growth factor receptor 2-positive (HER2+) breast cancer remains controversial. Neoadjuvant chemotherapy may risk overtreatment, whereas surgery first fails to identify patients with residual disease in need of escalated adjuvant systemic therapy. We investigated patient characteristics associated with receipt of neoadjuvant chemotherapy.

METHODS

Adult women with cT1-T2/N0, HER2+ breast cancer between 2013 and 2017 in the National Cancer Database who underwent surgery within 8 months of diagnosis were included. Patients were classified as receiving neoadjuvant chemotherapy versus a surgery-first approach. We assessed the sociodemographic and clinical predictors of neoadjuvant chemotherapy versus surgery first and associations between neoadjuvant chemotherapy and breast cancer treatments using multivariable regression models.

RESULTS

We identified 56,784 women, of whom 12,758 (22%) received neoadjuvant chemotherapy, 29,139 (53%) received adjuvant chemotherapy, 12,907 (24%) received no chemotherapy, and 1980 were missing chemotherapy information. After adjustment, cT2 stage was the strongest predictor of neoadjuvant chemotherapy compared with surgery first. Younger age and later diagnosis year were positively associated with receipt of neoadjuvant chemotherapy. In contrast, hormone receptor positivity, Black race, rural county, and government-funded or no health insurance were inversely associated with neoadjuvant chemotherapy. In multivariable analyses, patients who received neoadjuvant chemotherapy were more likely to have a mastectomy (vs. lumpectomy) and sentinel lymph node biopsy or no nodal surgery (vs. axillary lymph node dissection). Patients who received neoadjuvant chemotherapy were more likely to receive multi-agent (vs. single-agent) chemotherapy than those who received adjuvant chemotherapy.

CONCLUSIONS

Substantial differences in the utilization of neoadjuvant chemotherapy exist in women with HER2+ breast cancer, which reflect both clinical parameters and disparities. Optimal treatment strategies should be implemented equitably across sociodemographic groups.

The clinical significance of adenomatous polyposis coli (APC) and catenin Beta 1 (CTNNB1) genetic aberrations in patients with melanoma

BACKGROUND

Melanoma-intrinsic activated β-catenin pathway, the product of the catenin beta 1 (CTNNB1) gene, has been associated with low/absent tumor-infiltrating lymphocytes, accelerated tumor growth, metastases development, and resistance to anti-PD-L1/anti-CTLA-4 agents in mouse melanoma models. Little is known about the association between the adenomatous polyposis coli (APC) and CTNNB1 gene mutations in stage IV melanoma with immunotherapy response and overall survival (OS).

METHODS

We examined the prognostic significance of somatic APC/CTNNB1 mutations in the Cancer Genome Atlas Project for Skin Cutaneous Melanoma (TCGA-SKCM) database. We assessed APC/CTNNB1 mutations as predictors of response to immunotherapies in a clinicopathologically annotated metastatic patient cohort from three US melanoma centers.

RESULTS

In the TCGA-SKCM patient cohort (n = 434) presence of a somatic APC/CTNNB1 mutation was associated with a worse outcome only in stage IV melanoma (n = 82, median OS of APC/CTNNB1 mutants vs. wild-type was 8.15 vs. 22.8 months; log-rank hazard ratio 4.20, p = 0.011). APC/CTNNB1 mutation did not significantly affect lymphocyte distribution and density. In the 3-melanoma institution cohort, tumor tissues underwent targeted panel sequencing using two standards of care assays. We identified 55 patients with stage IV melanoma and APC/CTNNB1 genetic aberrations (mut) and 169 patients without (wt). At a median follow-up of more than 25 months for both groups, mut compared with wt patients had slightly more frequent (44% vs. 39%) and earlier (66% vs. 45% within six months from original diagnosis of stage IV melanoma) development of brain metastases. Nevertheless, time-to-development of brain metastases was not significantly different between the two groups. Fortunately, mut patients had similar clinical benefits from PD-1 inhibitor-based treatments compared to wt patients (median OS 26.1 months vs. 29.9 months, respectively, log-rank p = 0.23). Less frequent mutations in the NF1, RAC1, and PTEN genes were seen in the mut compared with wt patients from the 3-melanoma institution cohort. Analysis of brain melanoma tumor tissues from a separate craniotomy patient cohort (n = 55) showed that melanoma-specific, activated β-catenin (i.e., nuclear localization) was infrequent (n = 3, 6%) and not prognostic in established brain metastases.

CONCLUSIONS

APC/CTNNB1 mutations are associated with a worse outcome in stage IV melanoma and early brain metastases independent of tumor-infiltrating lymphocyte density. However, PD1 inhibitor-based treatments provide comparable benefits to both mut and wt patients with stage IV melanoma.

Disease-Associated Risk Variants in ANRIL Are Associated with Tumor-Infiltrating Lymphocyte Presence in Primary Melanomas in the Population-Based GEM Study

BACKGROUND

Genome-wide association studies have reported that genetic variation at ANRIL (CDKN2B-AS1) is associated with risk of several chronic diseases including coronary artery disease, coronary artery calcification, myocardial infarction, and type 2 diabetes mellitus. ANRIL is located at the CDKN2A/B locus, which encodes multiple melanoma tumor suppressors. We investigated the association of these variants with melanoma prognostic characteristics.

METHODS

The Genes, Environment, and Melanoma Study enrolled 3,285 European origin participants with incident invasive primary melanoma. For each of ten disease-associated SNPs at or near ANRIL, we used linear and logistic regression modeling to estimate, respectively, the per allele mean changes in log of Breslow thickness and ORs for presence of ulceration and tumor-infiltrating lymphocytes (TIL). We also assessed effect modification by tumor NRAS/BRAF mutational status.

RESULTS

Rs518394, rs10965215, and rs564398 passed false discovery and were each associated (P ≤ 0.005) with TILs, although only rs564398 was independently associated (P = 0.0005) with TILs. Stratified by NRAS/BRAF mutational status, rs564398*A was significantly positively associated with TILs among NRAS/BRAF mutant, but not wild-type, cases. We did not find SNP associations with Breslow thickness or ulceration.

CONCLUSIONS

ANRIL rs564398 was associated with TIL presence in primary melanomas, and this association may be limited to NRAS/BRAF-mutant cases.

IMPACT

Pathways related to ANRIL variants warrant exploration in relationship to TILs in melanoma, especially given the impact of TILs on immunotherapy and survival.

Are we choosing wisely? Drivers of preoperative MRI use in breast cancer patients

INTRODUCTION

Factors contributing to the use of preoperative MRI remain poorly understood.

METHODS

Data from a randomized controlled trial of stage 0-3 breast cancer patients undergoing breast conserving surgery between 2016 and 2018 were analyzed.

RESULTS

Of the 396 patients in this trial, 32.6% had a preoperative MRI. Patient age, race, ethnicity, tumor histology, and use of neoadjuvant therapy were significant predictors of MRI use. On multivariate analysis, younger patients with invasive lobular tumors were more likely to have a preoperative MRI. Rates also varied significantly by individual surgeon (p < 0.001); in particular, female surgeons (39.9% vs. 24.0% for male surgeons, p = 0.001) and those in community practice (58.9% vs. 14.2% for academic, p < 0.001) were more likely to order preoperative MRI. Rates declined over the two years of the study, particularly among female surgeons.

CONCLUSIONS

Preoperative MRI varies with patient age and tumor histology; however, there remains variability by individual surgeon.

Talimogene Laherparepvec (T-VEC) for the Treatment of Advanced Locoregional Melanoma After Failure of Immunotherapy: An International Multi-Institutional Experience

BACKGROUND

Talimogene laherparepvec (T-VEC) is an oncolytic virus approved for the treatment of unresectable, recurrent melanoma. The role of T-VEC after progression on systemic immunotherapy (IO) remains undefined. The goal of this study was to characterize the efficacy of T-VEC after failure of IO in patients with unresectable metastatic melanoma.

METHODS

An international, multi-institutional review of AJCC version 8 stage IIIB-IV melanoma patients treated with T-VEC after failure of IO was performed at six centers from October 2015-December 2020. Primary outcome was in-field response; secondary outcomes included analyses of in-field and overall progression-free survival (PFS) and in-field and overall disease-free survival (DFS) after a complete response. Subset analysis of T-VEC initiation sequentially after or concurrently with IO was performed.

RESULTS

Of 112 patients, median age at T-VEC initiation was 69 years (range 21-93); 65 (58%) were male. Before T-VEC, 57% patients received one IO regimen, 42% received two or more, with most patients (n = 74, 66%) receiving T-VEC sequential to IO. Most were stage 3C (n = 51, 46%) at T-VEC initiation, 29 (26%) received injections to nodal disease. Over median follow-up of 14 months, in-field response at final T-VEC injection was 37% complete (CR), 14% partial (PR). T-VEC initiation sequentially or concurrently did not significantly affect in-field response (p = 0.26). Median in-field PFS was 15 months (95% confidence interval 4.6-NE). Median overall DFS after CR was 32 months (95% confidence interval 17-NE).

CONCLUSIONS

T-VEC after failure of IO is effective in unresectable, metastatic stage IIIB-IV melanoma. T-VEC initiation sequentially or concurrently did not significantly affect in-field response.

Bridging Endocrine Therapy for HR+/HER2- Resectable Breast Cancer: Is it Safe?

BACKGROUND

The COVID-19 pandemic has required new treatment paradigms to limit exposures and optimize hospital resources, including the use of neoadjuvant endocrine therapy (NAET) as bridging therapy for HR+/HER2-invasive tumors and DCIS. While this approach has been used in locally advanced disease, it is unclear how it may affect outcomes in resectable HR+/HER2- tumors.

METHODS

Women ≥18 years diagnosed with in situ (Tis) or non-metastatic HR+/HER2- breast cancer from March-May 2019 and 2020 were included. Fisher's exact test and two-sample t test were used to compare baseline characteristics and surgical outcomes between strata. Sub-analysis was performed between patients who received primary surgery vs a bridging NAET approach.

RESULTS

Despite similar clinical characteristics, patients in 2019 were more likely to have a surgery-first approach (75% vs 42%, P-value = .0007), receive surgery sooner (22 vs 29 days, P-value < .001), and within 60 days from diagnosis date (100% vs 85%, P-value = .0301). Neoadjuvant endocrine therapy was a more prevalent approach in 2020 (48% vs 7%, P-value < .0001). Rates of clinical to pathologic up-staging remained consistent across primary surgery vs bridging NAET subgroups (P-value = .9253).

DISCUSSION

Pandemic-driven treatment protocols provide a unique opportunity to assess the utility of bridging endocrine therapy for resectable HR+/HER2- tumors. Differences in clinical and pathologic staging were similar across groups and did not appear to be affected by receipt of NAET. Our limited cohort demonstrates this strategic therapeutic avenue can optimize health care utilization and may be a reasonable approach when delaying surgery is preferred.

An Unusual Case of BIA-ALCL Associated with Prolonged/Complicated Biocell-Textured Expander, followed by Smooth Round Breast Implant Exposure, and Concurrent Use of Adalimumab

SUMMARY

Breast implant-associated anaplastic large-cell lymphoma (BIA-ALCL) is a malignancy associated with textured breast implants. BIA-ALCL is typically restricted to the periprosthetic capsule, presenting as a unilateral recurrent seroma years after placement of a textured breast implant. Current estimates suggest an incidence of one in 3300 for patients with Allergan Biocell textured implants. As of February 6, 2019, U.S. Medical Device Reporting associated with BIA-ALCL showed 457 unique cases of BIA-ALCL, with 24 "unverified and potentially inaccurate" cases associated with a nontextured implant. As of February of 2019, there were 688 reported cases to date worldwide. To date, there are no published case reports of BIA-ALCL associated exclusively with smooth implants or with smooth implants after textured expanders, and there has been no reported smooth-only case in any registry, database, or journal worldwide. The authors present a case of BIA-ALCL associated with smooth round implants and textured tissue expanders. A 56-year-old woman was treated for left stage IIA invasive ductal carcinoma with bilateral mastectomies and immediate reconstruction with bilateral subpectoral textured tissue expanders. She underwent exchange to Mentor smooth-round implants, and completed adjuvant chemotherapy. Magnetic resonance imaging and examination 4.5 years after implant placement showed no abnormal findings. The patient had left breast trauma 5 years following implant placement while taking adalimumab, and developed an open wound requiring explantation. A recurrent seroma developed, and tested positive for BIA-ALCL on cytology. Surgical pathologic examination after total capsulectomy demonstrated stage IA BIA-ALCL. To the authors' knowledge, this is the first case report of BIA-ALCL in a patient with textured expanders followed by prolonged exposure to smooth round implants.

Gender Bias in Surgical Oncology Fellowship Recommendation Letters: Gaining Progress

OBJECTIVE

Gender bias has been identified in letters of recommendation (LOR) in many different surgical training fields. Among surgeons, women comprise over 30% of the full-time faculty positions nationally and surgical oncology is one of the most gender diverse surgical subspecialties. We sought to determine if bias existed in LOR submitted to a Complex General Surgical Oncology (CGSO) fellowship.

DESIGN

LOR for the CGSO fellowship were retrospectively analyzed from applicants at a single institution over an 8-year period (2013-2020). The linguistic content of the letters was analyzed using Linguistic Inquiry and Word Count (LIWC2015), a validated text analysis program. Using multivariable analysis, LOR were compared by gender of both applicant and letter writer to explore the association between gender and the characteristics of the applicants and letter writers.

SETTING

University of North Carolina at Chapel Hill (UNC), Division of Surgical Oncology and Endocrine Surgery.

PARTICIPANTS

Applicants interviewed for the CSGO fellowship program at the UNC from 2013 to 2020 as well as all applicants from the 2018 application cycle, regardless of interview status.

RESULTS

About 841 letters from 219 interviewed applicants throughout the 2013 to 2020 surgical oncology fellowship application cycles were included. No difference in authenticity, clout, analytic thinking, or emotional tone of the letters was seen when comparing men and women applicants. Of the 41 word categories analyzed, only "references to achievement" in LOR written for women was significantly higher when compared to LOR written for men (p = 0.01). Interestingly, significantly more women applicants had at least 1 LOR written by a woman (p = 0.04). A subset analysis of all applicants regardless of interview status from the 2018 cycle included 294 LOR from 77 applicants. With the inclusion of noninterviewed applicants, LOR for men had more analytic tone than LOR for women (p = 0.02), otherwise there were no significant differences between the groups.

CONCLUSIONS

Very few differences in LOR were found for applicants at a CGSO fellowship program based on applicant or letter writer gender. The lack of gender bias demonstrates progress within the field of surgical oncology, likely a result of recent work and educational effort in this area. Efforts to expand this progress into other surgical sub-specialties are necessary.

Use and Costs of Sentinel Lymph Node Biopsy in Non-Ulcerated T1b Melanoma: Analysis of a Population-Based Registry

BACKGROUND

The utility of sentinel lymph node biopsy (SLNB) for non-ulcerated T1b melanoma is debated and associated costs are poorly characterized. Prior work using institutional registries may overestimate the incidence of nodal positivity in this population.

OBJECTIVE

The aim of this study was to estimate the use of SLNB, positivity prevalence, and procedural costs in patients with non-ulcerated T1b melanoma using a population-based registry.

METHODS

We identified patients with clinically node-negative, non-ulcerated melanoma 0.8-1.0 mm thick (T1b according to the 8th edition standard of the American Joint Committee on Cancer) in the Surveillance, Epidemiology, and End Results database from 2010 to 2016. The prevalence of SLNB procedures and positive sentinel nodes were calculated. Factors associated with SLNB and sentinel node positivity were assessed using logistic regression. Medicare reimbursement costs and patient out-of-pocket expenses for SLNB and wide local excision (WLE) versus WLE alone were estimated.

RESULTS

Among 7245 included patients, 3835(53%) underwent SLNB, 156 (4.1%, 95% confidence interval 3.5-4.7) of whom had a positive SLNB. Younger age, >1 mitosis per mm², female sex, and truncal tumor location were associated with higher odds of positivity. The estimated SLNB cost to identify one patient with stage III disease was $71,700 (range $54,648-$83,172). Out-of-pocket expenses for a Medicare patient were estimated to be $652 for a WLE and SLNB and $79 for a WLE alone.

CONCLUSIONS

In this population-based study, only 4% of selected non-ulcerated T1b patients had a positive SLNB, which is lower than prior reports. At the population level, SLNB is associated with high costs per prognostic information gained.

Effect of Clear vs Standard Covered Masks on Communication With Patients During Surgical Clinic Encounters: A Randomized Clinical Trial

Importance

During the COVID-19 pandemic, wearing masks has become necessary, especially within health care. However, to our knowledge, the consequences of mask wearing on communication between surgeons and patients have not been studied.

Objective

To evaluate the effects of clear vs standard covered masks on communication during surgical clinic encounters.

Design

This randomized clinical trial examined communication between surgeons and their patients when surgeons wore clear vs covered masks in surgical outpatient clinics at a single academic medical center. New patients were recruited from participating surgeons' clinic schedules.

Interventions

Surgeons wore either clear masks or covered masks for each clinic visit with a new patient, based on a per-visit randomization plan.

Main Outcomes and Measures

The primary outcome measures included patient perceptions of (1) surgeon communication and (2) trust in surgeons, as well as (3) quantitative assessments and (4) qualitative assessments regarding patient impressions of the surgeon's mask. After the clinic encounter, patients completed a verbal survey including validated Clinician and Group Consumer Assessment of Healthcare Providers and Systems questions. Additional questions involved surgeon empathy, trust, and the patient's impression of the surgeon's mask. Data were analyzed by comparing patient data in the clear vs covered groups using Cochran-Mantel-Haenszel tests, and comments were analyzed for themes.

Results

Two hundred patients were enrolled from 15 surgeons' clinics spanning 7 subspecialties. When surgeons wore a clear mask, patients rated their surgeons higher for providing understandable explanations (clear, 95 of 100 [95%] vs covered, 78 of 100 [78%]; P < .001), demonstrating empathy (clear, 99 [99%] vs covered, 85 [85%]; P < .001), and building trust (clear, 94 [94%] vs covered, 72 [72%]; P < .001). Patients preferred clear masks (clear, 100 [100%] vs covered, 72 [72%]; P < .001), citing improved surgeon communication and appreciation for visualization of the face. Conversely, 8 of 15 surgeons (53%) were unlikely to choose the clear mask over their standard covered mask.

Conclusions and Relevance

This randomized clinical trial demonstrates that patients prefer to see their surgeon's face. Surgeons who wore clear masks were perceived by patients to be better communicators, have more empathy, and elicit greater trust. Because masks will remain part of the health care landscape for some time, deliberate attention to preserving communication within the surgeon-patient relationship is warranted.

Trial Registration

ClinicalTrials.gov Identifier: NCT04595695.

Active surveillance of patients who have sentinel node positive melanoma: An international, multi-institution evaluation of adoption and early outcomes after the Multicenter Selective Lymphadenectomy Trial II (MSLT-2)

BACKGROUND

For patients with sentinel lymph node (SLN)-positive cutaneous melanoma, the Second Multicenter Selective Lymphadenectomy trial demonstrated equivalent disease-specific survival (DSS) with active surveillance using nodal ultrasound versus completion lymph node dissection (CLND). Adoption and outcomes of active surveillance in clinical practice and in adjuvant therapy recipients are unknown.

METHODS

In a retrospective cohort of SLN-positive adults treated at 21 institutions in Australia, Europe, and the United States from June 2017 to November 2019, the authors evaluated the impact of active surveillance and adjuvant therapy on all-site recurrence-free survival (RFS), isolated nodal RFS, distant metastasis-free survival (DMFS), and DSS using Kaplan-Meier curves and Cox proportional hazard models.

RESULTS

Among 6347 SLN biopsies, 1154 (18%) were positive and had initial negative distant staging. In total, 965 patients (84%) received active surveillance, 189 (16%) underwent CLND. Four hundred thirty-nine patients received adjuvant therapy (surveillance, 38%; CLND, 39%), with the majority (83%) receiving anti-PD-1 immunotherapy. After a median follow-up of 11 months, 220 patients developed recurrent disease (surveillance, 19%; CLND, 22%), and 24 died of melanoma (surveillance, 2%; CLND, 4%). Sixty-eight patients had an isolated nodal recurrence (surveillance, 6%; CLND, 4%). In patients who received adjuvant treatment without undergoing prior CLND, all isolated nodal recurrences were resectable. On risk-adjusted multivariable analyses, CLND was associated with improved isolated nodal RFS (hazard ratio [HR], 0.36; 95% CI, 0.15-0.88), but not all-site RFS (HR, 0.68; 95% CI, 0.45-1.02). Adjuvant therapy improved all-site RFS (HR, 0.52; 95% CI, 0.47-0.57). DSS and DMFS did not differ by nodal management or adjuvant treatment.

CONCLUSIONS

Active surveillance has been adopted for most SLN-positive patients. At initial assessment, real-world outcomes align with randomized trial findings, including in adjuvant therapy recipients.

LAY SUMMARY

For patients with melanoma of the skin and microscopic spread to lymph nodes, monitoring with ultrasound is an alternative to surgically removing the remaining lymph nodes. The authors studied adoption and real-world outcomes of ultrasound monitoring in over 1000 patients treated at 21 centers worldwide, finding that most patients now have ultrasounds instead of surgery. Although slightly more patients have cancer return in the lymph nodes with this strategy, typically, it can be removed with delayed surgery. Compared with up-front surgery, ultrasound monitoring results in the same overall risk of melanoma coming back at any location or of dying from melanoma.

Factors Associated with Nodal Pathologic Complete Response Among Breast Cancer Patients Treated with Neoadjuvant Chemotherapy: Results of CALGB 40601 (HER2+) and 40603 (Triple-Negative) (Alliance)

BACKGROUND

De-escalation of axillary surgery after neoadjuvant chemotherapy (NAC) requires careful patient selection. We seek to determine predictors of nodal pathologic complete response (ypN0) among patients treated on CALGB 40601 or 40603, which tested NAC regimens in HER2+ and triple-negative breast cancer (TNBC), respectively.

PATIENTS AND METHODS

A total of 760 patients with stage II-III HER2+ or TNBC were analyzed. Those who had axillary surgery before NAC (N = 122), or who had missing pretreatment clinical nodal status (cN) (N = 58) or ypN status (N = 41) were excluded. The proportion of patients with ypN0 disease was estimated for those with and without breast pathologic complete response (pCR) according to pretreatment nodal status.

RESULTS

In 539 patients, the overall ypN0 rate was 76.3% (411/539) to 93.2% (245/263) in patients with breast pCR and 60.1% (166/276) with residual breast disease (RD) (P < 0.0001). For patients who were cN0 pretreatment, the ypN0 rate was 88.8% (214/241), 96.3% (104/108) with breast pCR, and 82.7% (110/133) with RD. For patients who were cN1, 66.2% (157/237) converted to ypN0, 91.7% (111/121) with breast pCR and 39.7% (46/116) with RD. For patients who were cN2/3, 65.6% (40/61) converted to ypN0, 88.2% (30/34) with breast pCR and 37.0% (10/27) with RD. On multivariable analysis, only pretreatment clinical nodal status and breast pCR/RD were associated with ypN0 status (both P < 0.0001).

CONCLUSIONS

Breast pCR and pretreatment nodal status are predictive of ypN0 axillary nodal involvement, with < 5% residual nodal disease among cN0 patients who experience breast pCR. These findings support the incorporation of axillary surgery de-escalation strategies into NAC trials.

Does acral lentiginous melanoma subtype account for differences in patterns of care in Black patients?

BACKGROUND

Melanoma-specific outcomes for Black patients are worse when compared to non-Hispanic white (NHW) patients. We sought to evaluate whether acral lentiginous melanoma, seen more commonly in Black patients, was associated with racial disparities in outcomes METHODS: The National Cancer Database was analyzed for major subtypes of stage I-IV melanoma diagnosed from 2004 to 2016. The association between Black race and (Siegel et al., Jan) 1 acral melanoma diagnosis and (Bradford et al., Apr) 2 receipt of major amputation for surgical management of melanoma was evaluated using multivariable logistic regression.

RESULTS

251,864 patients were included (1453 Black). Black patients had increased odds of acral melanoma (odds ratio [OR] = 27.6, 95% CI]: 24.4, 31.2) compared to NHW patients. Black patients still had higher odds ratios of major amputation across all stages after adjusting for acral histology and other potential confounders CONCLUSIONS: Increased prevalence of acral melanoma in Black patients does not fully account for increased receipt of major amputation.

Targeting the IL-2 inducible kinase in melanoma; a phase 2 study of ibrutinib in systemic treatment-refractory distant metastatic cutaneous melanoma: preclinical rationale, biology, and clinical activity (NCI9922)

BACKGROUND

IL-2 inducible kinase (ITK) is highly expressed in metastatic melanomas and its inhibition suppresses melanoma cell proliferation. We hypothesize that ibrutinib has a direct antitumor effect in melanoma cell lines and that treatment of metastatic melanomas with ibrutinib induces antitumor responses.

METHODS

We assessed the ibrutinib effect on melanoma cell proliferation, apoptosis, and motility. Patients with metastatic melanoma refractory to PD-1 and MAPK inhibitors (if BRAFV600-mutant) were treated with ibrutinib, 840 mg PO QD, as part of a phase II clinical trial (clinicaltrials.gov NCT02581930).

RESULTS

Melanoma cell lines frequently express ITK, YES1, and EGFR. Ibrutinib suppressed cell motility and proliferation in most cell lines. Eighteen patients (13 male; median age 63.5 years, range 37-82; 12 with ipilimumab resistance) were enrolled. The most frequent side effects were fatigue (61%), anorexia (50%), hyponatremia (28%), nausea, and vomiting (22% each). No antitumor responses were seen. At a median follow-up of 6 months (0.3-35.8 months), the median progression-free survival was 1.3 months (range 0.2-5.5 months). Fifteen patients were discontinued from the study due to progression, and 14 patients had died from metastatic melanoma. All archived tumors expressed ITK, 41% had no expression of p16 and PTEN, and 61% had absent tumor-infiltrating lymphocytes (TILs). Ibrutinib significantly suppressed proliferating (Ki67+) CD19+ peripheral blood mononuclear cells and had no significant effect on other lymphocyte subsets.

CONCLUSION

Ibrutinib did not induce any meaningful clinical benefit. ITK expression may not be clinically relevant. Treatment-refractory metastatic melanomas have other fundamental defects (i.e. absent PTEN and p16 expression, absent TILs) that may contribute to an adverse prognosis.

Surveillance of Sentinel Node-Positive Melanoma Patients with Reasons for Exclusion from MSLT-II: Multi-Institutional Propensity Score Matched Analysis

BACKGROUND

In sentinel lymph node (SLN)-positive melanoma, two randomized trials demonstrated equivalent melanoma-specific survival with nodal surveillance vs completion lymph node dissection (CLND). Patients with microsatellites, extranodal extension (ENE) in the SLN, or >3 positive SLNs constitute a high-risk group largely excluded from the randomized trials, for whom appropriate management remains unknown.

STUDY DESIGN

SLN-positive patients with any of the three high-risk features were identified from an international cohort. CLND patients were matched 1:1 with surveillance patients using propensity scores. Risk of any-site recurrence, SLN-basin-only recurrence, and melanoma-specific mortality were compared.

RESULTS

Among 1,154 SLN-positive patients, 166 had ENE, microsatellites, and/or >3 positive SLN. At 18.5 months median follow-up, 49% had recurrence (vs 26% in patients without high-risk features, p < 0.01). Among high-risk patients, 52 (31%) underwent CLND and 114 (69%) received surveillance. Fifty-one CLND patients were matched to 51 surveillance patients. The matched cohort was balanced on tumor, nodal, and adjuvant treatment factors. There were no significant differences in any-site recurrence (CLND 49%, surveillance 45%, p = 0.99), SLN-basin-only recurrence (CLND 6%, surveillance 14%, p = 0.20), or melanoma-specific mortality (CLND 14%, surveillance 12%, p = 0.86).

CONCLUSIONS

SLN-positive patients with microsatellites, ENE, or >3 positive SLN constitute a high-risk group with a 2-fold greater recurrence risk. For those managed with nodal surveillance, SLN-basin recurrences were more frequent, but all-site recurrence and melanoma-specific mortality were comparable to patients treated with CLND. Most recurrences were outside the SLN-basin, supporting use of nodal surveillance for SLN-positive patients with microsatellites, ENE, and/or >3 positive SLN.

The Role of Intraoperative Radiation in Early-stage Breast Cancer

Intraoperative radiation therapy (IORT) is a specialized form of accelerated partial breast irradiation in which a single dose of radiation is delivered to the tumor bed at the time of breast conserving surgery. With completion of radiation to the tumor bed at the time of surgery, IORT promises improved patient convenience, compliance, and quality of life. In addition, with its potentially skin-sparing properties and ability to deliver a high biologically effective dose to the tumor bed while reducing dose to nontarget tissues, IORT results in different but overall less toxicities compared with other modalities of radiation for breast cancer. However, skepticism over the role of IORT in breast cancer exists, and the 2 randomized trials that have analyzed IORT as the definitive radiation component of breast conservation therapy have shown an increase in local recurrence rates with IORT compared with whole breast irradiation, but similar rates of overall survival. In this review, we discuss the practicalities of IORT, the prospective data supporting and negating the role of IORT in lieu of whole breast irradiation, and the toxicity after IORT in early-stage breast cancer. We also review the role of IORT as a radiation boost and specific strategies for successful implementation of IORT in breast cancer.

Brain Tumor Microenvironment and Angiogenesis in Melanoma Brain Metastases

BACKGROUND

High tumor-infiltrating lymphocytes (TILs) and hemorrhage are important prognostic factors in patients who have undergone craniotomy for melanoma brain metastases (MBM) before 2011 at the University of Pittsburgh Medical Center (UPMC). We have investigated the prognostic or predictive role of these histopathologic factors in a more contemporary craniotomy cohort from the University of North Carolina at Chapel Hill (UNC-CH). We have also sought to understand better how various immune cell subsets, angiogenic factors, and blood vessels may be associated with clinical and radiographic features in MBM.

METHODS

Brain tumors from the UPMC and UNC-CH patient cohorts were (re)analyzed by standard histopathology, tumor tissue imaging, and gene expression profiling. Variables were associated with overall survival (OS) and radiographic features.

RESULTS

The patient subgroup with high TILs in craniotomy specimens and subsequent treatment with immune checkpoint inhibitors (ICIs, n=7) trended to have longer OS compared to the subgroup with high TILs and no treatment with ICIs (n=11, p=0.059). Bleeding was significantly associated with tumor volume before craniotomy, high melanoma-specific expression of basic fibroblast growth factor (bFGF), and high density of CD31+αSMA- blood vessels. Brain tumors with high versus low peritumoral edema before craniotomy had low (17%) versus high (41%) incidence of brisk TILs. Melanoma-specific expression of the vascular endothelial growth factor (VEGF) was comparable to VEGF expression by TILs and was not associated with any particular prognostic, radiographic, or histopathologic features. A gene signature associated with gamma delta (gd) T cells was significantly higher in intracranial than same-patient extracranial metastases and primary melanoma. However, gdT cell density in MBM was not prognostic.

CONCLUSIONS

ICIs may provide greater clinical benefit in patients with brisk TILs in MBM. Intratumoral hemorrhage in brain metastases, a significant clinical problem, is not merely associated with tumor volume but also with underlying biology. bFGF may be an essential pathway to target. VEGF, a factor principally associated with peritumoral edema, is not only produced by melanoma cells but also by TILs. Therefore, suppressing low-grade peritumoral edema using corticosteroids may harm TIL function in 41% of cases. Ongoing clinical trials targeting VEGF in MBM may predict a lack of unfavorable impacts on TIL density and/or intratumoral hemorrhage.

Impact of Cavity Shave Margins on Margin Status in Patients with Pure Ductal Carcinoma In Situ

BACKGROUND

We examined the impact of cavity shave margins (CSMs) on margin status in patients with pure ductal carcinoma in situ (DCIS) undergoing partial mastectomy (PM).

METHODS

One hundred and nine patients from 2 multicenter, randomized controlled trials were identified with pure DCIS (no invasive cancer). Surgeons performed their best PM, with specimen radiography and resection of selective margins per surgeon discretion. Patients were then randomized to have CSM resected or not. A positive margin was defined as <2 mm from ink.

RESULTS

Median patient age was 63 years; median size of DCIS was 1.20 cm; 43.6% of patients had high-grade DCIS; and 58 (53.2%) patients were randomized to take CSM. The "shave" and "no-shave" groups were well-matched for age, race, ethnicity, palpability, grade, and size of DCIS. Although 33 (56.9%) of the patients in the shave group had a positive margin before randomization, only 12 (20.7%) had a positive margin after randomization to CSM (p < 0.001). In the no-shave group, 17 patients (33.3%) had a positive margin. Controlling for size and grade of DCIS, taking CSM resulted in a nearly 65% reduction in the positive-margin rate (odds ratio 0.366; 95% CI, 0.136 to 0.981; p = 0.046). Size of DCIS remained an independent predictor of positive margins in the model (odds ratio 1.646; 95% CI, 1.227 to 2.209; p = 0.001).

CONCLUSIONS

CSM reduces positive-margin rates in patients with pure DCIS, and can be a practical solution for DCIS patients who tend to have a high rate of margin positivity.

Direct Comparison of In-Person Versus Virtual Interviews for Complex General Surgical Oncology Fellowship in the COVID-19 Era

BACKGROUND

In the era of coronavirus disease 2019 (COVID-19), many Complex General Surgical Oncology (CGSO) fellowship programs implemented virtual interviews (VI) during the 2020 interview season. At our institution, we had the unique opportunity to conduct an in-person interview (IPI) prior to the pandemic-related travel restrictions, and a VI after the restrictions were in place.

OBJECTIVE

The goal of this study was to understand how the VI model compares with the traditional IPI approach.

METHODS

Online surveys were distributed to both groups, collecting feedback on their interview experience. Responses were evaluated using a two-sample t test assuming equal variances.

RESULTS

Twenty-three of 26 (88%) applicants completed the survey. Most applicants reported that the interview gave them a satisfactory understanding of the CGSO fellowship (100% IPI, 92% VI) and the majority in both groups felt that the interview experience allowed them to accurately represent themselves (92% and 82%, respectively). All participants in the IPI group felt they were able to get an adequate understanding of the culture of the program, while only 64% in the VI group agreed with that statement (p = 0.02). IPI applicants were more likely to agree that the interview experience was sufficient to allow them to make a ranking decision (92% vs. 54%; p = 0.04).

CONCLUSIONS

While the VI modality offers several advantages over the IPI, it still falls short in conveying some of the more subjective aspects of the programs, including program culture. Strategies to provide applicants with better insight into these areas during the VI will be important moving forward.

Pleomorphic Invasive Lobular Carcinoma of the Breast With Extracellular Mucin and HER2 Amplification

Invasive lobular carcinoma with extracellular mucin is an uncommon pattern of invasive breast carcinoma. The 5th Edition of the World Health Organization Classification of Breast Tumors states that it is unknown whether these tumors are a subtype of mucinous carcinoma or invasive lobular carcinoma. Invasive lobular carcinoma with extracellular mucin frequently presents as a palpable mass and may be more likely to be grade 2 to 3 and HER2-positive than classic invasive lobular carcinoma. This case of pleomorphic invasive lobular carcinoma with extracellular mucin was detected by imaging only and was HER2-amplified, suggesting that a subset of these tumors may be clinically occult with an aggressive phenotype. Invasive lobular carcinoma with extracellular mucin is infrequently encountered and awareness of this entity is helpful in avoiding misdiagnosis.

Characterization of Sentinel Lymph Node Immune Signatures and Implications for Risk Stratification for Adjuvant Therapy in Melanoma

BACKGROUND

Although sentinel lymph node (SLN) biopsy is a standard procedure used to identify patients at risk for melanoma recurrence, it fails to risk-stratify certain patients accurately. Because processes in SLNs regulate anti-tumor immune responses, the authors hypothesized that SLN gene expression may be used for risk stratification.

METHODS

The Nanostring nCounter PanCancer Immune Profiling Panel was used to quantify expression of 730 immune-related genes in 60 SLN specimens (31 positive [pSLNs], 29 negative [nSLNs]) from a retrospective melanoma cohort. A multivariate prediction model for recurrence-free survival (RFS) was created by applying stepwise variable selection to Cox regression models. Risk scores calculated on the basis of the model were used to stratify patients into low- and high-risk groups. The predictive power of the model was assessed using the Kaplan-Meier and log-rank tests.

RESULTS

During a median follow-up period of 6.3 years, 20 patients (33.3%) experienced recurrence (pSLN, 45.2% [14/31] vs nSLN, 20.7% [6/29]; p = 0.0445). A fitted Cox regression model incorporating 12 genes accurately predicted RFS (C-index, 0.9919). Improved RFS was associated with increased expression of TIGIT (p = 0.0326), an immune checkpoint, and decreased expression of CXCL16 (p = 0.0273), a cytokine important in promoting dendritic and T cell interactions. Independent of SLN status, the model in this study was able to stratify patients into cohorts at high and low risk for recurrence (p < 0.001, log-rank).

CONCLUSIONS

Expression profiles of the SLN gene are associated with melanoma recurrence and may be able to identify patients as high or low risk regardless of SLN status, potentially enhancing patient selection for adjuvant therapy.

The Prognostic Value of Axillary Staging Following Neoadjuvant Chemotherapy in Inflammatory Breast Cancer

BACKGROUND

Inflammatory breast cancer (IBC) has historically been characterized by high rates of recurrence and poor survival; however, there have been significant improvements in systemic therapy. We sought to investigate modern treatment of IBC and define the yield and prognostic significance of axillary lymph nodes after neoadjuvant chemotherapy (NAC).

METHODS

Women with clinical stage T4d, N0-N3, M0 IBC from 2012 to 2016 in the National Cancer Database were included. Kaplan-Meier survival curves and Cox regression were used to assess mortality by receptor subtype and nodal status.

RESULTS

We identified 5265 patients; 37% hormone receptor (HR) +/HER2 - , 19% HR +/HER2 + , 18% HR -/HER2 + , and 26% triple-negative, and 5-year overall survival was 51.6%. Only 34% were treated according to guidelines with NAC, modified radical mastectomy, and adjuvant radiation. Pathologically positive lymph nodes (ypN +) after NAC varied by subtype and clinical nodal status (cN) ranging from 82% in cN + HR +/HER2 - patients to 19% in cN0 HR -/HER2 + patients. ypN + strongly correlated with survival in all subtypes with the most pronounced impact in HR +/HER2 + patients, with 90% 5-year overall survival in ypN0 versus 66% for ypN + (HR 4.29, 95% CI 1.58-11.70, p = 0.03).

CONCLUSIONS

Five-year survival in M0 IBC is 51.6%. Positive nodes after NAC varied by subtype and clinical N status but is sufficiently high and provided meaningful prognostication in all subtypes to support continued routine pathologic assessment. Future study is warranted to identify reliable, less morbid, methods of staging the axilla in IBC patients appropriate for deescalation of axillary surgery.

Reflector Localization of Breast Lesions and Parameters Associated with Positive Surgical Margins in Women Undergoing Breast Conservation Surgery

OBJECTIVE

To evaluate our experience with reflector localization of breast lesions and parameters influencing surgical margins in patients with a malignant diagnosis.

METHODS

A retrospective institution review board-approved review of our institutional database was performed for breast lesions preoperatively localized from September 1, 2016, through December 31, 2017. Wire localizations were excluded. From electronic medical records and imaging, the following data was recorded: breast density, lesion type and size, reflector placement modality and number placed, reflector distance from lesion and skin, excision of lesion and reflector, tissue volume, margin status, and final pathology. Statistical analysis was performed with a Fisher's exact test, Mann-Whitney test, and logistic regression. P < 0.05 was significant.

RESULTS

A total of 111 reflectors were deployed in the breasts of 103 women with 109 breast lesions. Ninety (81.1%) reflectors were placed under mammographic guidance and 21 (18.9%) under US. The lesions consisted of 68 (62.4%) masses, 17 (15.6%) calcifications, 2 (1.8%) architectural distortions, and 22 (20.2%) biopsy markers. Fourteen (21.2%) of 66 cases with a preoperative malignant diagnosis had a positive surgical margin. Final pathology, including 6 lesions upgraded to malignancy on excision, demonstrated 72 (66.0%) malignant, 22 (20.2%) high-risk, and 15 (13.8%) benign lesions. Univariate and multivariate analysis revealed no statistically significant parameters (lesion type or size, placement modality, reflector distance to skin or lesion, specimen radiography or pathology) were associated with a positive surgical margin.

CONCLUSION

Reflector localization is an alternative to wire localization of breast lesions. There were no lesion-specific or technical parameters affecting positive surgical margins.

Decreased survival and increased recurrence in Merkel cell carcinoma significantly linked with immunosuppression

BACKGROUND

Merkel cell carcinoma (MCC) is a rare and aggressive form of skin cancer. It is an immunogenic tumor as evident by its association with Polyomavirus, immunotherapy response, and increased prevalence in the immunosuppressed population.

OBJECTIVE

We sought to evaluate the impact of known clinicopathological determinants and immunosuppression on the risk of recurrence and mortality of MCC patients.

METHODS

A retrospective, observational cohort study of patients diagnosed and/or treated with MCC at two tertiary academic institutions. We compared clinicopathological determinants, treatment modalities, and immunosuppression status on clinical outcomes of recurrence, disease-specific survival, and overall survival.

RESULTS

We evaluated 90 patients within our study and 34% had a cancer recurrence during follow-up. Patients with recurrence were significantly more likely to be immunosuppressed (32% vs 5%; P = .001). Estimated 5-year recurrence was 43%, and immunosuppressed patients were significantly more likely to recur (Hazard ratio [HR] 3.67 [1.80-7.51]; P < .0001). Immunosuppressed patients had significantly elevated cancer-specific mortality (HR 6.11[1.61-23.26]; P = .008).

LIMITATIONS

Retrospective review with a prolonged observation period and changing treatment modalities.

CONCLUSION

Immunocompromised patients had a threefold increased incidence of 5-year mortality and over twofold increased incidence of any recurrence as non-immunocompromised patients. Patients' immunosuppressive status should be considered when making decisions regarding treatment, surveillance, and prognostication.

MRI-guided core needle biopsy of the breast: Radiology-pathology correlation and impact on clinical management

OBJECTIVE

Breast MRI is used to screen high-risk patients and determine extent of disease in breast cancer (BC) patients. The goal of this study was to determine the pathologic correlates of breast MRI abnormalities biopsied under MRI guidance.

METHODS

We retrospectively identified 101 MRI-guided core needle biopsies (CNB) of the breast from 79 women over a 4-year period. MRI-detected lesions biopsied with ultrasound or stereotactic guidance were excluded. MRI studies and pathology were reviewed by breast radiologists and pathologists.

RESULTS

Of the 79 patients, 72 (91%) had a history of prior (n = 13) or concurrent (n = 59) BC. There were 101 MRI abnormalities: 60 (59%) with non-mass enhancement (NME) and 41 (41%) with mass enhancement. Pathology was benign in 83/101 (82%), including in the majority of NME lesions (43/60, 72%). The most common benign findings were: fibrocystic changes (FCC) (49%), sclerosing lesions (13%), and fibroadenoma (FA) (9%). There were 18 (18%) malignant diagnoses: 8 (44%) invasive lobular carcinoma (ILC), 7 (39%) ductal carcinoma in situ (DCIS), and 3 (17%) invasive ductal carcinoma (IDC). Of the 18 malignant diagnoses, 16 (89%) occurred in 14 unique patients with concurrent BC. Based on the malignant MRI-guided CNB, 6 (46%) of these patients had additional (sentinel lymph node biopsy or contralateral breast surgery) or more extensive (wider lumpectomy) surgery.

CONCLUSION

In this series, most MRI-guided CNB of the breast were benign. The vast majority of malignant diagnoses occurred in patients with concurrent BC and frequently resulted in changes in clinical management.

High intratumoral tryptophan metabolism is a poor predictor of response to pembrolizumab (pembro) in metastatic melanoma (MM): Results from a prospective trial using baseline C11-labeled alpha-methyl tryptophan (C11-AMT) PET imaging for response prediction

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Background: Molecular imaging of metabolic pathways critical for effector T cell response other than glucose could predict response to PD1 inhibitors. We have previously shown that high expression of tryptophan metabolic pathway enzymes in stage III/IV melanoma correlates with reduced abundance of tumor-infiltrating lymphocytes (TILs, ASCO 2019, e21014). Here we investigated C11-AMT, a PET tracer that images tryptophan metabolism, as a predictor of response to pembro in patients (pts) with PD1 inhibitor-naïve MM. Methods: In this trial (NCT03089606) pts must have had measurable MM by RECIST, have undergone IV contrast CT, FDG-PET, and C11-AMT PET scan (30-40 min dynamic imaging), plus a mandatory tumor biopsy prior to pembro treatment. Results: 21 pts (16 males; 15 stage IV; median age 61) had all 3 baseline scans and evaluable research biopsies. 13 pts were non-progressors (CR = 4, PR = 6, and SD = 3). At a median f/u of 13.7 mons (2.8-25.1+), 6 pts are dead from MM, 11 are alive without MM and 4 are alive with MM. 46 tumor lesions were assessed by all 3 scans. Of the pts with tumor lesion, C11-AMT PET SUVmax < 7 and skewness < +0.3 of the tumor lesion with the highest C11-AMT SUVmax was associated with non-progression by RECIST (SUVmax < 7/skewness < +0.3 in progressors vs. non-progressors; Fisher’s 2-tail test p= 0.055). The corresponding association between baseline FDG-PET (SUVmax < 14 and skewness < +0.3) with treatment response was insignificant ( p= 0.08). There was a weak (Spearman ρ= 0.33) but significant correlation ( p= 0.001) in SUVmax between FDG-PET and C11-AMT among the 46 tumors analyzed. There was no significant correlation between melanoma-specific expression of the tryptophan- (TPH1, TPH2, IDO1, TDO2, LAT1) and glucose-metabolizing enzymes (GLUT1, HK1, HK3) by immunohistochemistry. Response to pembro trends to associate with present TILs (Fisher’s p= 0.087). Conclusions: Baseline C11-AMT PET imaging using simple radiomics measures (highest metabolic activity, SUVmax, and tumor heterogeneity, skewness) may better predict clinical benefit from pembro in MM than FDG PET. Variability in C11-AMT’s SUVmax cannot be solely explained by FDG-PET’s SUVmax, suggesting that these two imaging modalities may provide complementary information about intratumoral metabolic dysregulation that may relate with pembro response. Texture analysis using LifeX v4.0 will be presented at the meeting. Clinical trial information: NCT03089606 .

A risk prediction model for the development of subsequent primary melanoma in a population-based cohort

BACKGROUND

Guidelines for follow-up of patients with melanoma are based on limited evidence.

OBJECTIVES

To guide skin surveillance, we developed a risk prediction model for subsequent primary melanomas, using demographic, phenotypical, histopathological, sun exposure and genomic risk factors.

METHODS

Using Cox regression frailty models, we analysed data for 2613 primary melanomas from 1266 patients recruited to the population-based Genes, Environment and Melanoma study in New South Wales, Australia, with a median of 14 years' follow-up via the cancer registry. Discrimination and calibration were assessed.

RESULTS

The median time to diagnosis of a subsequent primary melanoma decreased with each new primary melanoma. The final model included 12 risk factors. Harrell's C-statistic was 0·73 [95% confidence interval (CI) 0·68-0·77], 0·65 (95% CI 0·62-0·68) and 0·65 (95% CI 0·61-0·69) for predicting second, third and fourth primary melanomas, respectively. The risk of a subsequent primary melanoma was 4·75 times higher (95% CI 3·87-5·82) for the highest vs. the lowest quintile of the risk score. The mean absolute risk of a subsequent primary melanoma within 5 years was 8·0 ± SD 4.1% after the first primary melanoma, and 46·8 ± 15·0% after the second, but varied substantially by risk score.

CONCLUSIONS

The risk of developing a subsequent primary melanoma varies considerably between individuals and is particularly high for those with two or more primary melanomas. The risk prediction model and its associated nomograms enable estimation of the absolute risk of subsequent primary melanoma, on the basis of on an individual's risk factors, and can be used to tailor surveillance intensity, communicate risk and provide patient education. What's already known about this topic? Current guidelines for the frequency and length of follow-up to detect new primary melanomas in patients with one or more previous primary melanomas are based on limited evidence. People with one or more primary melanomas have, on average, a higher risk of developing another primary invasive melanoma, compared with the general population, but an accurate way of estimating individual risk is needed. What does this study add? We provide a comprehensive risk prediction model for subsequent primary melanomas, using data from 1266 participants with melanoma (2613 primary melanomas), over a median 14 years' follow-up. The model includes 12 risk factors comprising demographic, phenotypical, histopathological and genomic factors, and sun exposure. It enables estimation of the absolute risk of subsequent primary melanomas, and can be used to tailor surveillance intensity, communicate individual risk and provide patient education.

Phase II Single-Arm Study of Preoperative Letrozole for Estrogen Receptor-Positive Postmenopausal Ductal Carcinoma In Situ: CALGB 40903 (Alliance)

PURPOSE

Primary endocrine therapy for ductal carcinoma in situ (DCIS) as a potential alternative to surgery has been understudied. This trial explored the feasibility of a short-term course of letrozole and sought to determine whether treatment results in measurable radiographic and biologic changes in estrogen receptor (ER)-positive DCIS.

PATIENTS AND METHODS

A phase II single-arm multicenter cooperative-group trial was conducted in postmenopausal patients diagnosed with ER-positive DCIS without invasion. Patients were treated with letrozole 2.5 mg per day for 6 months before surgery. Breast magnetic resonance imaging (MRI) was obtained at baseline, 3 months, and 6 months. The primary end point was change in 6-month MRI enhancement volume compared with baseline.

RESULTS

Overall, 79 patients were enrolled and 70 completed 6 months of letrozole. Of these, 67 patients had MRI data available for each timepoint. Baseline MRI volumes ranged from 0.004 to 26.3 cm3. Median reductions from baseline MRI volume (1.4 cm3) were 0.6 cm3 (61.0%) at 3 months (P < .001) and 0.8 cm3 (71.7%) at 6 months (P < .001). Consistent reductions were seen in median baseline ER H-score (228; median reduction, 15.0; P = .005), progesterone receptor H-score (15; median reduction, 85.0; P < .001), and Ki67 score (12%; median reduction, 6.3%; P = .007). Of the 59 patients who underwent surgery per study protocol, persistent DCIS remained in 50 patients (85%), invasive cancer was detected in six patients (10%), and no residual DCIS or invasive cancer was seen in nine patients (15%).

CONCLUSIONS

In a cohort of postmenopausal women with ER-positive DCIS, preoperative letrozole resulted in significant imaging and biomarker changes. These findings support future trials of extended endocrine therapy as primary nonoperative treatment of some DCIS.