Single-Photon Emission Computed Tomography/Computed Tomography Utilization for Extremity Melanomas at a High-Volume Center.

INTRODUCTION: Planar lymphoscintigraphy (PL) is commonly used in mapping before sentinel lymph node biopsy (SLNB) for invasive cutaneous melanoma. Recently, single-photon emission computed tomography (SPECT)/ computed tomography (CT) has been utilized, in addition to PL, for detailed anatomic information and detection of sentinel lymph nodes (SLNs) outside of the primary nodal basin in truncal and head and neck melanoma. Following a protocol change due to COVID-19, our institution began routinely obtaining both PL and SPECT-CT imaging for all melanoma SLN mapping. We hypothesized that SPECT-CT is associated with higher instances of SLNBs from "nontraditional" nodal basins (NTNB) for extremity melanomas. METHODS: Patients with extremity melanoma (2017-2022) who underwent SLNB were grouped into SPECT-CT with PL versus PL alone. Outcomes were total SLNs removed, + or-SLN status, total NTNB sampled, and postoperative complication rate. Poisson regression and logistic regression models were used to assess association of SPECT-CT with patient outcomes. RESULTS: Of 380 patients with extremity melanoma, 42.11% had SPECT-CT. There were no differences between the groups with regards to age at diagnosis or sex. From 2020 to 2022, all patients underwent SPECT-CT. SPECT-CT was associated with increased odds of SLNB from an NTNB, (odds ratio = 2.39 [95% confidence interval: 1.25-4.67]). There was no difference in odds of number of SLNs sampled, SLN positivity rate, or postoperative complication rate with SPECT-CT. CONCLUSIONS: Routine SPECT-CT was associated with higher incidence of SLNB in NTNB but did not increase number of SLNs removed or SLN positivity rate. The added value of routine SPECT-CT in cutaneous melanoma of the extremities remains to be defined.

Prognostic gene expression profile testing to inform use of adjuvant therapy: A survey of melanoma experts.

OBJECTIVES: To investigate current practices and attitudes regarding use of adjuvant immunotherapy and prognostic gene expression profile (GEP) testing among melanoma medical and surgical oncologists. METHODS: An anonymous RedCap-based survey was emailed to ~300 melanoma experts. RESULTS: Respondents generally favored adjuvant immunotherapy over observation (73% for all Stage IIIA, 50% for Stage IIB/IIC) and cited a minimum 10-year recurrence risk of 11%-20% (48%) or 21%-30% (33%) to justify treatment, but acknowledged that risks of serious adverse events may outweigh potential benefits for some Stage IIB/IIC patients. While GEP test results did not strongly influence decision-making regarding follow-up or intervention, most were receptive to randomized trials using GEP testing to identify subsets of Stage IIB/IIC (74%) and Stage IB/IIA (54%) patients who may not or may, respectively, benefit from adjuvant therapy. CONCLUSION: Although most respondents do not routinely use GEP testing, many would participate in clinical trials to determine clinical utility.

Longer Wait Times Do Not Adversely Impact 90-Day Mortality in Patients With Stages I-III Gastric Cancer.

Introduction Gastric cancer is one of the leading causes of cancer-related death in the United States. Surgery remains integral to the curative management of non-metastatic gastric cancer. However, delays to the date of surgery for gastric cancer patients are commonplace. To investigate the impact of treatment delays on gastric cancer mortality, we conducted a multivariable analysis of over 36,000 patients. Materials & methods After querying the National Cancer Database and excluding patients who did not meet inclusion criteria, our sample included 36,598 patients with stage I-III gastric cancer. We ran multivariable logistic regressions by regressing 90-day mortality on wait time. Other co-variables included sex, race, age, area of residence, comorbidities, insurance, histology, tumor grade, tumor stage, resection margins, treatment facility type, and treatment with chemotherapy. Results Our results demonstrated that each day of increased waiting time is associated with a 0.5% decrease in 90-day mortality. Other statistically significant predictors of higher 90-day mortality risk included male sex, black or white race, living in a small metropolitan or non-metropolitan area, older age, more severe comorbidities, non-private insurance, non-gastric stromal tumor cancer, non-well differentiated tumors, worse clinical stage, residual cancer, treatment at non-academic center, and no adjuvant/neoadjuvant chemotherapy. Conclusion These findings demonstrate that patients with longer wait times until surgery do not experience worse outcomes. These results are reassuring and can be cited to alleviate patient concerns.

The Treatment of a Novel Epidermal Growth Factor Receptor (EGFR)-GRB2 Genetic Mutation Using Osimertinib in Metastatic Non-Small Cell Lung Cancer.

Mutations in the epidermal growth factor receptor (EGFR) have been implicated in nearly one-third of non-small-cell lung cancers. For patients harboring non-traditional mutations, genomic and transcriptomic sequencing can help direct treatment. As cancer genomics evolves, novel driver mutations continue to be uncovered. We report on a unique EGFR-GRB2 fusion in a 48-year-old female never-smoker. This patient presented with stage IV lung adenocarcinoma (T2aN3M1) with metastatic disease in the iliac wing and liver. Despite systemic treatment, this patient continued to progress. On whole transcriptome sequencing, this patient was found to have a novel EGFR-GRB2 RNA fusion transcript similar to other EGFR fusions described in the literature. After treatment with osimertinib, this patient experienced remarkable clinical and radiological improvements. We believe that, especially for patients with metastatic lung cancer, the presence of novel driver mutations should be investigated. Potentially, patients harboring similar mutations may demonstrate analogous improvements with targeted treatment using the most recent generation of tyrosine kinase inhibitors.

Plasminogen Activator Inhibitor 1 (PAI1) Promotes Actin Cytoskeleton Reorganization and Glycolytic Metabolism in Triple-Negative Breast Cancer.

Migration and invasion of cancer cells constitute fundamental processes in tumor progression and metastasis. Migratory cancer cells commonly upregulate expression of plasminogen activator inhibitor 1 (PAI1), and PAI1 correlates with poor prognosis in breast cancer. However, mechanisms by which PAI1 promotes migration of cancer cells remain incompletely defined. Here we show that increased PAI1 drives rearrangement of the actin cytoskeleton, mitochondrial fragmentation, and glycolytic metabolism in triple-negative breast cancer (TNBC) cells. In two-dimensional environments, both stable expression of PAI1 and treatment with recombinant PAI1 increased migration, which could be blocked with the specific inhibitor tiplaxtinin. PAI1 also promoted invasion into the extracellular matrix from coculture spheroids with human mammary fibroblasts in fibrin gels. Elevated cellular PAI1 enhanced cytoskeletal features associated with migration, actin-rich migratory structures, and reduced actin stress fibers. In orthotopic tumor xenografts, we discovered that TNBC cells with elevated PAI1 show collagen fibers aligned perpendicular to the tumor margin, an established marker of invasive breast tumors. Further studies revealed that PAI1 activates ERK signaling, a central regulator of motility, and promotes mitochondrial fragmentation. Consistent with known effects of mitochondrial fragmentation on metabolism, fluorescence lifetime imaging microscopy of endogenous NADH showed that PAI1 promotes glycolysis in cell-based assays, orthotopic tumor xenografts, and lung metastases. Together, these data demonstrate for the first time that PAI1 regulates cancer cell metabolism and suggest targeting metabolism to block motility and tumor progression. IMPLICATIONS: We identified a novel mechanism through which cancer cells alter their metabolism to promote tumor progression.

Enhanced Bone Metastases in Skeletally Immature Mice.

Bone constitutes the most common site of breast cancer metastases either at time of presentation or recurrent disease years after seemingly successful therapy. Bone metastases cause substantial morbidity, including life-threatening spinal cord compression and hypercalcemia. Given the high prevalence of patients with breast cancer, health-care costs of bone metastases (>$20,000 per episode) impose a tremendous economic burden on society. To investigate mechanisms of bone metastasis, we developed femoral artery injection of cancer cells as a physiologically relevant model of bone metastasis. Comparing young (~6 weeks), skeletally immature mice to old (~6 months) female mice with closed physes (growth plates), we showed significantly greater progression of osteolytic metastases in young animals. Bone destruction increased in the old mice following ovariectomy, emphasizing the pathologic consequences of greater bone turnover and net loss. Despite uniform initial distribution of breast cancer cells throughout the hind limb after femoral artery injection, we observed preferential formation of osteolytic bone metastases in the proximal tibia. Tropism for the proximal tibia arises in part because of TGF-ß, a cytokine abundant in both physes of skeletally immature mice and matrix of bone in mice of all ages. We also showed that age-dependent effects on osteolytic bone metastases did not occur in male mice with disseminated breast cancer cells in bone. These studies establish a model system to specifically focus on pathophysiology and treatment of bone metastases and underscore the need to match biologic variables in the model to relevant subsets of patients with breast cancer.