Dwarkasing, Jvalini

AbstractBackgroundThe Merlin assay for melanoma‐risk assessment has become commercially available to reduce the rate of unnecessary sentinel lymph node biopsies (SLNB) in SLNB‐eligible patients with cutaneous melanoma. Merlin low‐risk patients are recommended to undergo wide local excision (WLE) of the primary tumor, whereas Merlin high‐risk patients are recommended to undergo both SLNB and WLE. Here, we compared the cost of a Merlin testing strategy to that of a no‐testing strategy (usual care) before prescribing SLNB.MethodsWe identified T1 and T2 patients who underwent WLE and SLNB but not completion lymph node dissection between 2007 and 2018. Controls were T1 patients who only underwent WLE. Costs for WLE and SLNB were calculated by converting institutional cost data to standardized Medicare reimbursement rates. We then developed a decision tree to compare the cost of Merlin testing to that of a no‐testing strategy (usual care).ResultsThe average standardized cost of WLE was $2066, whereas the cost of WLE and SLNB was $11,976 based on Medicare rates. At a cost below $7350 for T1b melanoma and $4600 for T1b to T2 melanoma, Merlin testing was cost‐saving compared to a no‐testing strategy (usual care), assuming Medicare reimbursement rates.ConclusionMerlin testing for T1b and T2 melanoma is potentially cost saving depending on the cost of the molecular assay and SLNB reimbursement rates. In addition to being cost saving, Merlin is expected to improve health‐related quality of life.

AbstractBackgroundThe assessment of the sentinel lymph node is a cornerstone of melanoma staging. However, ~80% of sentinel lymph node biopsies (SLNB) are negative and nontherapeutic, and patients are unnecessarily exposed to surgery‐related complications. Here, we gauged the potential of the Merlin assay to reduce SLNB‐associated complications. The Merlin assay uses clinicopathologic variables and tumor gene expression profiling to identify low‐risk patients who may forgo SLNB.MethodsWe utilized the Merlin test development cohort to determine SLNB complication rates for procedures performed between 2004 and 2018 at Mayo Clinic. Complications evaluated were lymphedema, seroma, infection/cellulitis, hematoma, and wound dehiscence. Patients who underwent a completion lymph node dissection were excluded.ResultsA total of 558 patients were included. The overall 90‐day complication rate specific to SLNB (1 year for lymphedema) was 17.4%. The most common complications were seroma (9.3%), infection/cellulitis (4.8%), and lymphedema (4.3%). All three were more common in patients with a lower extremity primary tumor location versus other locations. With Merlin test results applied, SLNB‐related complications would have decreased by 59%.ConclusionSLNB is a safe procedure but carries a significant complication rate. Merlin testing might reduce the need for SLNB and its associated complications.

e22088 Background: In recent years, adjuvant therapy trials in stage III melanoma have been successful and trials have started with the inclusion of stage IIB/C patients. However, stage IIA melanoma patients are currently not eligible for adjuvant therapy, even though a large part of all melanoma related deaths occur in this patient group. Therefore, a strong clinical need has emerged for diagnostic tools that can identify high-risk patients who currently have no access to adjuvant therapy. Here, we sought to assess the ability of a recently introduced clinicopathologic gene expression model (CP-GEP) (Bellomo et al., JCO Precis Oncol. 2020: in press) to select stage IIA patients at high risk for disease relapse, upon design of a stage-specific operating point. Methods: We assessed the prognostic performance of the CP-GEP model in all 141 stage IIA patients from a Mayo Clinic cohort of 837 consecutive melanoma patients who had a sentinel lymph node biopsy (SLNb) performed within 90 days of their diagnosis. The CP-GEP model combines Breslow thickness and patient age, with the expression of 8 genes in the primary tumor. Moreover, it stratifies patients according to their risk of relapse: CP-GEP High Risk or CP-GEP Low Risk, based on an operating point that was specifically developed for stage IIA. This stage-specific operating point was selected to fulfill the following criteria: hazard ratio RFS > 2 with a p-value < 0.05, and risk groups of similar size. The main clinical endpoint was five-year relapse free survival (RFS). Results: The CP-GEP High Risk group corresponds to 45% (63/141) of all stage IIA patients and captures 62% (18/29) of the total relapses in this substage. Moreover, CP-GEP High Risk patients relapse more frequently than CP-GEP Low Risk patients (RFS of 56% versus 78%; HR, 2.23; P < 0.05). The prognosis for stage IIA CP-GEP High Risk patients in our cohort is worse than for stage IIC/IIIA patients with reported RFS ranging from 63% to 77%. Conclusions: The CP-GEP model can be optimized by designing a stage-specific operating point, to identify a subset of stage IIA patients with an increased risk for disease relapse, not very different from IIC/IIIA patients. Therefore, stage IIA CP-GEP High Risk patients may be considered for inclusion in adjuvant trials. Independent validation studies are ongoing for the newly developed operating point. [Table: see text]

10068 Background: The identification of early stage melanoma patients at high risk for relapse is still difficult. Roughly 50% of melanoma deaths occur in patients who were initially diagnosed with nonmetastatic melanoma. Therefore, a strong clinical need has emerged for diagnostic tools that can identify melanoma patients at high risk for relapse. Here, we assessed the performance of a recently developed model (Bellomo et al., JCO Precis Oncol. 2020: in press), combining clinicopathologic and gene expression variables (CP-GEP), in identifying melanoma patients that have a high risk for disease relapse. Methods: We assessed the prognostic performance of the CP-GEP model in a cohort of 837 consecutive melanoma patients from Mayo Clinic who had a sentinel lymph node biopsy (SLNb) performed within 90 days of their diagnosis. The CP-GEP model combines Breslow thickness and patient age, with the expression of 8 genes in the primary tumor, to stratify patients according to their risk of relapse: CP-GEP High Risk or CP-GEP Low Risk. The main clinical endpoint of this study was five-year relapse free survival (RFS). Results: Patients were stratified based on SLNb status and CP-GEP classification. 76% of the patients were SLNb negative and had an RFS of 79% versus 52% for SLNb positive patients; HR, 3.21; P < 0.0001. 60% of the patients were identified as CP-GEP High Risk and had an RFS of 62% versus 87% for CP-GEP Low Risk patients; HR, 4.12; P < 0.0001. Within the SLNb negative group (637 patients of which 65% stage I), 51% of patients were classified as CP-GEP High Risk. Here, RFS was 70% for CP-GEP High Risk patients versus 89% for CP-GEP Low Risk patients; HR, 3.61; P < 0.0001. The prognosis of these CP-GEP High Risk patients is similar to stage IIC/IIIA patients with reported RFS ranging from 63% to 77%. This confirms the heterogeneity in prognosis among patients with stage I/II melanoma disease. Conclusions: The CP-GEP model can be successfully used to stratify patients based on their risk for relapse. In particular, it can be used to identify SLNb negative patients with a high risk for disease relapse who may benefit from therapeutic interventions. Independent validation studies are ongoing to validate the CP-GEP model in various patient populations. [Table: see text]

PURPOSEMore than 80% of patients who undergo sentinel lymph node (SLN) biopsy have no nodal metastasis. Here, we describe a model that combines clinicopathologic and molecular variables to identify patients with thin- and intermediate-thickness melanomas who may forgo the SLN biopsy procedure because of their low risk of nodal metastasis.PATIENTS AND METHODSGenes with functional roles in melanoma metastasis were discovered by analysis of next-generation sequencing data and case-control studies. We then used polymerase chain reaction to quantify gene expression in diagnostic biopsy tissue across a prospectively designed archival cohort of 754 consecutive thin- and intermediate-thickness primary cutaneous melanomas. Outcome of interest was SLN biopsy metastasis within 90 days of melanoma diagnosis. A penalized maximum likelihood estimation algorithm was used to train logistic regression models in a repeated cross-validation scheme to predict the presence of SLN metastasis from molecular, clinical, and histologic variables.RESULTSExpression of genes with roles in epithelial-to-mesenchymal transition (glia-derived nexin, growth differentiation factor 15, integrin-β3, interleukin 8, lysyl oxidase homolog 4, transforming growth factor-β receptor type 1, and tissue-type plasminogen activator) and melanosome function (melanoma antigen recognized by T cells 1) were associated with SLN metastasis. The predictive ability of a model that only considered clinicopathologic or gene expression variables was outperformed by a model that included molecular variables in combination with the clinicopathologic predictors Breslow thickness and patient age (area under the receiver operating characteristic curve, 0.82; 95% CI, 0.78 to 0.86; SLN biopsy reduction rate, 42%; negative predictive value, 96%).CONCLUSIONA combined model that included clinicopathologic and gene expression variables improved the identification of patients with melanoma who may forgo the SLN biopsy procedure because of their low risk of nodal metastasis.