The prognostic significance of microsatellites in cutaneous melanoma

Macroscopic tumor dimension, sentinel lymph node outcome, and survival analysis among cutaneous melanoma

BACKGROUND

Cutaneous melanoma is characterized by a high risk of metastasis to distant organs and a substantial mortality rate. For planning treatment and assessing outcomes, the Breslow micrometric measurement is critical. The tumor macroscopic dimension is not considered a prognostic parameter in cutaneous melanoma, although there are studies showing that tumor size is an independent prognostic factor for melanoma-specific survival. Therefore, this study aimed to evaluate the macroscopic dimension of melanoma and other known prognostic factors (i.e., Breslow index, mitoses, regression, and ulceration) as predictors of sentinel lymph node outcome and survival outcome.

METHODS

We performed a retrospective cross-sectional study of 227 melanoma lesions subjected to sentinel lymph node biopsy at two Brazilian referral centers.

RESULTS

On univariate analysis, there was a statistically significant correlation between the largest macroscopic tumor dimension and the sentinel lymph node result (P = 0.001); however, on multivariate analysis considering all evaluated parameters, there was no significant difference between the sentinel lymph node result and the tumor macroscopic dimension (P = 0.2689). Regarding melanoma-specific survival, the macroscopic dimension showed no significant correlation (P = 0.4632) in contrast to Breslow's dimension (P < 0.0001).

CONCLUSION

The Breslow thickness was the only significant factor related to both the sentinel lymph node outcome and melanoma specific survival among the evaluated variables.

Role of Concurrent Ultrasound Surveillance of Sentinel Node-Positive Node Fields in Melanoma Patients Having Routine Cross-Sectional Imaging

PURPOSE

In sentinel node-positive (SN+ve) melanoma patients, active surveillance with regular ultrasound examination of the node field has become standard, rather than completion lymph node dissection (CLND). A proportion of these patients now receive adjuvant systemic therapy and have routine cross-sectional imaging (computed tomography [CT] or positron emission tomography [PET]/CT). The role of concurrent ultrasound (US) surveillance in these patients is unclear. The purpose of our study was to describe the modality of detection of nodal recurrence in SN+ve node fields.

METHODS

SN+ve melanoma patients who did not undergo CLND treated at a single institution from January 1, 2016 to December 31, 2020 were included.

RESULTS

A total of 225 SN+ve patients with a median follow-up of 23 months were included. Of these, 119 (53%) received adjuvant systemic therapy. Eighty (36%) developed a recurrence at any site; 24 (11%) recurred first in the SN+ve field, of which 12 (5%) were confirmed node field recurrence only at 2 months follow-up. The nodal recurrences were first detected by ultrasound in seven (3%), CT in seven (3%), and PET/CT in seven (3%) patients. All nodal recurrences evident on US were also evident on PET/CT and vice versa.

CONCLUSIONS

The high rate of recurrences outside the node field and the identification of all US-detected nodal recurrences on concurrent cross-sectional imaging modalities suggest that routine concurrent ultrasound surveillance of the node-positive field may be unnecessary for SN+ve melanoma patients having routine cross-sectional imaging.

A Review of Contemporary Guidelines and Evidence for Wide Local Excision in Primary Cutaneous Melanoma Management

Surgical wide local excision (WLE) remains the current standard of care for primary cutaneous melanoma. WLE is an elective procedure that aims to achieve locoregional disease control with minimal functional and cosmetic impairment. Despite several prospective randomised trials, the optimal extent of excision margin remains controversial, and this is reflected in the persistent lack of consensus in guidelines globally. Furthermore, there is now the added difficulty of interpreting existing trial data in the context of the evolving role of surgery in the management of melanoma, with our increased understanding of clinicopathologic and genomic prognostic markers leading to the often routine use of sentinel node biopsy (SNB) as a staging procedure, in addition to the development of adjuvant systemic therapies for high-risk disease. An ongoing trial, MelMarT-II, has been designed with the aim of achieving a definitive answer to guide this fundamental surgical decision.

The limited value of sentinel lymph node biopsy in lentigo maligna melanoma: A nomogram based on the results of 29 years of the nationwide dutch pathology registry (PALGA)

BACKGROUND

Lentigo maligna melanoma (LMM) predominantly presents in the head and neck of the elderly. The value of sentinel lymph node biopsy (SLNB) for LMM patients remains to be determined, as the reported average yield of positive lymph nodes is less than 10%. In this nationwide cohort study, we wanted to identify LMM patients with an increased risk of SLNB-positivity.

METHODS

LMM with an SLNB indication according to the 8th AJCC melanoma guidelines were retrospectively identified from the nationwide network and registry of histo- and cytopathology in the Netherlands (PALGA). A penalized (LASSO) logistic regression analysis was performed to determine the optimal combination of clinicopathological factors to predict a positive SLNB.

RESULTS

Between 1991 and 2020, 1989 LMM patients met our inclusion criteria. SLNB was performed in 16.7% (n = 333) and was positive in 7.5% (25/333). The false-negative rate was 21.9%. Clinically detectable regional lymph node (LN) metastases were found in 1.3% (n = 25). Clinicopathological characteristics best predictive for SLNB-positivity (Odds ratio; 95% CI) were age (0.95; 0.91-0.99), ulceration 1.59 (0.44-4.83), T4-stage (1.81; 0.43-6.2), male sex (1.97; 0.79-5.27), (lymph)angioinvasion (5.07; 0.94-23.31), and microsatellites (7.23; 1.56-32.7) (C-statistic 0.75). During follow-up, regional LN recurrences were detected in 4.2% (83/1989) of patients, of which the majority (74/83) had no evidence of regional LN metastases at baseline.

CONCLUSION

Our findings confirm the limited SLNB-positivity in LMM patients. Based on the identified high-risk clinicopathological features, a nomogram was developed to predict the risk of a positive SLNB.

The Diagnosis and Management of Cutaneous Metastases from Melanoma

Melanoma is one of the deadliest skin tumors, accounting for almost 90% of skin cancer mortality. Although immune therapy and targeted therapy have dramatically changed the prognosis of metastatic melanoma, many patients experience disease progression despite the currently available new treatments. Skin metastases from melanoma represent a relatively common event as first sign of advanced disease or a sign of recurrence. Skin metastases are usually asymptomatic, although in advanced stages, they can present with ulceration, bleeding, and superinfection; furthermore, they can cause symptoms related to compression on nearby tissues. Treatments vary from simple surgery resections to topical or intralesional local injections, or a combination of these techniques with the most recent systemic immune or target therapies. New research and studies should focus on the pathogenesis and molecular mechanisms of the cutaneous metastases of melanoma in order to shed light on the mechanisms underlying the different behavior and prognoses of different patients.

The Impact of Clinical and Histopathological Factors on Disease Progression and Survival in Thick Cutaneous Melanomas

Thick cutaneous melanomas (Breslow depth > 4 mm) are locally advanced tumors, generally associated with poor prognosis. Nevertheless, these tumors sometimes display unpredictable behavior. This study aims to analyze clinical and histopathological features that can influence the prognosis of thick melanomas. This is a retrospective study on 94 thick primary cutaneous melanomas diagnosed between 2012 and 2018 that were followed-up for at least five years to assess disease progression and survival. We evaluated the age, gender, tumor location, histological subtype, Breslow depth, Clark level, resection margins, mitotic index, the presence/absence of ulceration, necrosis, regression, microsatellites, neurotropism, lymphovascular invasion, and the pattern of tumor-infiltrating lymphocytes, and their association with disease progression and survival. By conducting univariate analysis, we found that progression-free survival (PFS) was significantly associated with female gender, the superficial spreading melanoma (SSM) subtype, mitotic index, necrosis, microsatellites, and perineural invasion. Overall survival (OS) was significantly associated with female gender, Breslow depth, SSM subtype, necrosis, microsatellites, and perineural invasion. Through multivariate Cox proportional hazards regression, we found that the only factors associated with PFS were Breslow depth, necrosis, microsatellites, and perineural invasion, while the factors associated with OS were Breslow depth, necrosis, microsatellites, and perineural invasion. Certain histopathological features such as Breslow depth, necrosis, microsatellites, and perineural invasion could explain differences in disease evolution. This is one of the first studies to demonstrate an association between necrosis and perineural invasion and outcomes in patients with thick melanomas. By identifying high-risk patients, personalized therapy can be provided for improved prognosis.

Invasive Cutaneous Melanoma: Evaluating the Prognostic Significance of Some Parameters Associated with Lymph Node Metastases

Background and Objectives: This study aimed to assess the clinical-pathological profile of patients with invasive cutaneous melanomas and to identify the parameters with a prognostic role in the lymph nodal spread of this malignant tumor. Materials and Methods: We performed a retrospective study on patients with invasive cutaneous melanomas who underwent surgery in the "Pius Brînzeu" County Clinical Emergency Hospital from Timișoara, Romania, and were evaluated for the status of loco-regional lymph nodes. We selected and analyzed some parameters searching for their relationship with lymph node metastases. Results: We identified 79 patients with invasive cutaneous melanomas (29 men and 50 women, mean age 59.36 years). A percentage of 58.3% of melanomas had Breslow tumor thickness >2 mm; 69.6% of melanomas showed a Clark level IV-V. Tumor ulceration was present in 59.5% of melanomas. A mitotic rate of ≥5 mitoses/mm² was observed in 48.1% of melanomas. Tumor-infiltrating lymphocytes (TILs), non-brisk, were present in 59.5% of cases and 22.8% of patients had satellite/in-transit metastasis (SINTM). Tumor regression was identified in 44.3% of cases. Lymph nodes metastases were found in 43.1% of patients. Statistical analysis showed that lymph node metastases were more frequent in melanomas with Breslow thickness >2 mm (p = 0.0002), high Clark level (p = 0.0026), mitotic rate >5 mitoses/mm² (p = 0.0044), ulceration (p = 0.0107), lymphovascular invasion (p = 0.0182), SINTM (p = 0.0302), and non-brisk TILs (p = 0.0302). Conclusions: The Breslow thickness >2 mm, high Clark level, high mitotic rate and ulceration are the most important prognostic factors for lymph nodal spread in cutaneous melanomas. However, some melanomas without these clinical-pathological features can have an unexpected, aggressive evolution, which entails the necessity of close and prolonged clinical follow-up of patients, including those with lesions considered without risk.

Prognostic role of microsatellites in melanoma and implications in the American Joint Committee on Cancer classification system: A cohort study

BACKGROUND

There is limited information on microsatellite survival outcomes in patients with melanoma.

OBJECTIVE

To evaluate survival outcomes in patients with microsatellites, assess their role within stage III stratification of the American Joint Committee on Cancer classification, and assess the results of sentinel lymph node biopsies in patients with microsatellites.

METHODS

A retrospective bicenter cohort study from 1998 to 2019 included patients with a diagnosis of invasive cutaneous melanoma.

RESULTS

Of a total of 5216 patients, 108 (2.1%) had microsatellites at initial staging. Survival analysis showed that microsatellites were an independent risk factor with decreased overall survival (OS), melanoma-specific survival (MSS), and disease-free survival, with hazard ratios of 1.57, 1.76, and 1.76, respectively. Stratified analysis in patients with stage III melanoma showed a 5-year OS of 35% (95% CI, 17.3%-73.4%) and a MSS of 45% (95% CI, 23.1-87.5) for patients with stage IIIB melanoma with microsatellites.

LIMITATIONS

Retrospective design of the study.

CONCLUSION

Microsatellites were associated with other adverse melanoma prognostic factors. A multivariate Cox regression analysis showed that they are an independent risk factor for worse OS, MSS, and disease-free survival. Patients with stage IIIB melanoma with microsatellites had worse OS and MSS, whereas patients with stage IIIC melanoma had worse OS but not MSS.

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

BACKGROUND AND OBJECTIVES

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Histological regression in melanoma: impact on sentinel lymph node status and survival

Regression in melanoma is an immunological phenomenon that results in partial or complete replacement of the tumor with variably vascular fibrous tissue, often accompanied by pigment-laden macrophages and chronic inflammation. In some cases, tumor-infiltrating lymphocytes (TILs) may represent the earliest phase of this process. The prognostic significance of regression has long been a matter of debate, with inconsistent findings reported in the literature to date. This study sought to determine whether regression in primary cutaneous melanomas predicted sentinel lymph node (SLN) status and survival outcomes in a large cohort of patients managed at a single centre. Clinical and pathological parameters for 8,693 consecutive cases were retrieved. Associations between regression and SLN status, overall survival (OS), melanoma-specific survival (MSS) and recurrence-free survival (RFS) were investigated using logistic and Cox regression. Histological evidence of regression was present in 1958 cases (22.5%). Regression was significantly associated with lower Breslow thickness, lower mitotic rate, and absence of ulceration (p < 0.0001). Multivariable analysis showed that regression in combination with TILs independently predicted a negative SLN biopsy (OR 0.33; 95% C.I. 0.20-0.52; p < 0.0001). Patients whose tumors showed both regression and TILs had the highest 10-year OS (65%, 95% C.I. 59-71%), MSS (85%, 95% C.I. 81-89%), and RFS (60%, 95% C.I. 54-66%). On multivariable analyses, the concurrent presence of regression and TILs independently predicted the lowest risk of death from melanoma (HR 0.69; 95% C.I. 0.51-0.94; p = 0.0003) as well as the lowest rate of disease recurrence (HR 0.71; 95% C.I. 0.58-0.85; p < 0.0001). However, in contrast, in the subgroup analysis of Stage III patients, the presence of regression predicted the lowest OS and RFS, with MSS showing a similar trend. Overall, these findings indicate a prognostically favorable role of regression in primary cutaneous melanoma. However, in Stage III melanoma patients, regression may be a marker of more aggressive disease.