Diagnostic accuracy of imaging studies for initial staging of T2b to T4b melanoma patients: A cross-sectional study

Brain metastases during follow-up of patients with resected cutaneous melanoma

Melanoma is among the most common tumors that disseminate to the brain. We analyzed patients with resected early-stage cutaneous melanoma who developed sole brain metastases and brain metastases accompanying other organ spreads and interpreted the clinical characteristics of these patients in this study. A total of 457 patients who developed any organ metastases during or after adjuvant therapy or in follow-up were included in the analysis. A total of 55 (12%) patients had brain metastases (M1d), and 402 patients had other (M1a,b,c) metastases. The majority of brain metastases (n = 36, 65.4%) were accompanied by other organ metastases, only 19 patients had sole brain metastases. Brain metastases were mostly in men (76.4 vs. 61.9%, P = 0.03), and extracerebral dissemination was more commonly associated with acral lentiginous melanoma histopathology (16.7 vs. 4.7%, P = 0.04). Brain metastasis was found to be associated with shorter survival (median survivals were 6.0 vs. 12.45 months, respectively, P = 0.0001). However, there was no difference in survival between patients with isolated brain involvements and patients with brain metastases accompanied by spread to other organs (median survivals were 6.0 vs. 5.85 months, respectively, P = 0.1). In conclusion, brain metastases are a very small portion of relapsed melanoma patients, and the numbers of isolated brain metastases are even smaller, thus the significance of routine brain scans for early detection of brain involvement in the follow-up of patients might be questionable and unnecessary.

European consensus-based interdisciplinary guideline for melanoma. Part 1: Diagnostics - Update 2024

This guideline was developed in close collaboration with multidisciplinary experts from the European Association of Dermato-Oncology (EADO), the European Dermatology Forum (EDF) and the European Organization for Research and Treatment of Cancer (EORTC). Recommendations for the diagnosis and treatment of melanoma were developed on the basis of systematic literature research and consensus conferences. Cutaneous melanoma (CM) is the most dangerous form of skin tumor and accounts for 90 % of skin cancer mortality. The diagnosis of melanoma can be made clinically and must always be confirmed by dermoscopy. If melanoma is suspected, a histopathological examination is always required. Sequential digital dermoscopy and whole-body photography can be used in high-risk patients to improve the detection of early-stage melanoma. If available, confocal reflectance microscopy can also improve the clinical diagnosis in special cases. Melanoma is classified according to the 8th version of the American Joint Committee on Cancer classification. For thin melanomas up to a tumor thickness of 0.8 mm, no further diagnostic imaging is required. From stage IB, lymph node sonography is recommended, but no further imaging examinations. From stage IIB/C, whole-body examinations with computed tomography or positron emission tomography CT in combination with magnetic resonance imaging of the brain are recommended. From stage IIB/C and higher, a mutation test is recommended, especially for the BRAF V600 mutation. It is important to perform a structured follow-up to detect relapses and secondary primary melanomas as early as possible. A stage-based follow-up regimen is proposed, which in the experience of the guideline group covers the optimal requirements, although further studies may be considered. This guideline is valid until the end of 2026.

A comprehensive analysis of metastatic disease following surgery for clinically localized cutaneous melanoma

BACKGROUND

The National Comprehensive Cancer Network considers "baseline staging" (whole body computed tomography or positron emission tomography scans with or without brain magnetic resonance imaging scans) for all patients with asymptomatic melanoma who had a positive sentinel lymph node biopsy result. The true yield of these workups is unknown.

METHODS

We created cohorts of adult patients with malignant melanoma using the National Cancer Database (2012-2020) to mimic 3 common scenarios: 1) clinically node-negative disease, with positive sentinel lymph node biopsy results; 2) clinically node-negative disease, with negative sentinel lymph node biopsy results; and 3) clinically node-positive disease, with confirmed lymph node metastases. Multivariable regression, supervised decision trees, and nomograms were constructed to assess the risk of metastases based on key features.

RESULTS

In total, 10 371 patients were in scenario 1, 55 172 were in scenario 2, and 4012 were in scenario 3. The proportion of patients with any metastatic disease (brain metastases) were as follows: 1.4% (0.3%) in scenario 1, 0.3% (<0.1%) in scenario 2, and 11.6% (1.6%) in scenario 3. On multivariable regression, Breslow depth greater than 4, ulceration, and lymphovascular invasion were associated with greater risk of metastatic disease. A supervised decision tree for patients in scenarios 1 and 2 found that the only groups with more than 2% risk of metastases were groups with T4 tumors or T2/T3 tumors with ulceration and lymphovascular invasion. Most groups had a negligible risk (<0.1%) of brain metastases.

CONCLUSION

This study is the first large analysis to guide the use of imaging for cutaneous melanoma. Among patients with clinically node negative disease, metastatic disease is uncommon, and brain metastases are exceedingly rare. Further investigation could promote a tailored approach to metastatic workups guided by individual risk factors.

False Positive Rate from Prospective Studies of PET-CT in Cutaneous Malignant Melanoma: A Systematic Review and Meta-Analysis

BACKGROUND

Cutaneous malignant melanoma (CMM) is increasing in prevalence and possesses the highest mortality rate of any skin cancer. Positron Emission Tomography and Computed Tomography (PET-CT) may be utilised in either radiological staging or surveillance, primarily in stage III-IV disease. False positive (FP) results lead to patient distress, increased costs, and unnecessary follow-up. The FP rate in CMM literature varies widely, altering calculations of positive predictive value and has not undergone pooled meta-analytic.

MATERIALS AND METHODS

A systematic review and meta-analysis of FP results in prospective studies of PET-CT in CMM was performed in accordance with PRISMA guidelines.

RESULTS

The systematic review produced 14 trials for inclusion. Patient-based reporting had the lowest pooled proportion of FP results with 5.8 % (95 % CI = 3.3 % to 8.8 %), lesion-based was highest with 9.1 % (95 % CI = 3.4 % to 17.2 %) and combined was 6.1 % (95 % CI = 4.3 % to 8.1 %). Bias was low to unclear other than for FP reporting. Heterogeneity (I2) was variable across all analyses. FP findings were mainly lymphatic, dermatological, respiratory, or skeletal. Diagnostic information was not provided.

CONCLUSIONS

This study was the first attempt to quantify the pooled proportion of FP results from PET-CT in CMM. A small number of studies (n = 14) were available due to the predominance of retrospective methodology. Due to inconsistent reporting the true proportion of FP results is unclear. Systemic distribution was expected but limited diagnostic information was provided. Repeat meta-analysis using retrospective work should be performed. Future work should be prospective with clearly documented FP proportion, distribution, diagnosis, and follow-up.

Diagnostic Performance of [18F]F-FDG Positron Emission Tomography (PET) in Non-Ophthalmic Malignant Melanoma: A Systematic Review and Meta-Analysis of More Than 10,000 Melanoma Patients

We described the diagnostic performance of [18F]F-FDG-PET in malignant melanoma by conducting a comprehensive systematic review and meta-analysis of the existing literature. The study was designed following PRISMA-DTA. Original articles with adequate crude data for meta-analytic calculations that evaluated [18F]F-FDG-PET and compared it with a valid reference standard were considered eligible. The pooled measurements were calculated based on the data level (patient/lesion-based). Regarding sub-groups, diagnostic performances were calculated for local, regional and distant involvement. The bivariate model was employed to calculate sensitivity and specificity. The initial search resulted in 6678 studies. Finally, 100 entered the meta-analysis, containing 82 patient-based (10,403 patients) and 32 lesion-based (6188 lesions) datasets. At patient level, overall, [18F]F-FDG-PET had pooled sensitivity and specificity of 81% (95%CI: 73-87%) and 92% (95%CI: 90-94%), respectively. To detect regional lymph node metastasis, the pooled sensitivity and specificity were 56% (95%CI: 40-72%) and 97% (95%CI: 94-99%), respectively. To detect distant metastasis, they were 88% (95%CI: 81-93%) and 94% (95%CI: 91-96%), respectively. At lesion level, [18F]F-FDG-PET had a pooled sensitivity and specificity of 70% (95%CI: 57-80%) and 94% (95%CI: 88-97%), respectively. Thus, [18F]F-FDG-PET is a valuable diagnostic modality for melanoma assessment. It was accurate in various clinical scenarios. However, despite its high specificity, it showed low sensitivity in detecting regional lymph node metastasis and could not replace lymph node biopsy.

Diagnostic Accuracy of Image-guided Biopsies for Diagnosis of Metastatic Melanoma in a Real-life Setting

Early detection of melanoma metastasis is essential in order to initiate treatment and improve patient prognosis. The aim of this study was to determine the diagnostic accuracy of different image-guided biopsy techniques in patients with melanoma. A cohort study of patients diagnosed with melanoma who had undergone image-guided biopsies (ultrasound-guided fine-needle aspiration cytology, ultrasound-guided core-needle biopsy, computerized tomography--guided fine-needle aspiration cytology and computerized tomography-guided core-needle biopsy) to detect melanoma metastasis between 2004 and 2021 was conducted. The reference standard was histological confirmation and/or clinical-radiological follow-up. Sensitivity, specificity, positive and negative predictive values were calculated. A total of 600 image--guided biopsies performed on 460 patients were included for analysis. Locoregional lesions represented 459 (76.5%) biopsies, and 141 (23.5%) were distant lesions. Of the included biopsies, 49 (8.2%) were insufficient for diagnosis. Overall, sensitivity and specificity were 92% (95% confidence interval 89-94) and 96% (95% confidence interval 91-99), respectively. Sensitivity sub-analyses revealed lower diagnostic accuracy values in the lung, inguinal lymph nodes, and computerized tomography-guided lesions under 1 cm. Limitations include spontaneous metastasis regression and arbitrary minimum follow-up period. Image-guided biopsies in patients with melanoma have high sensitivity and specificity for detection of regional or distant metastasis. Tissue type, location and tumour burden may influence the diagnostic accuracy of the test.

European consensus-based interdisciplinary guideline for melanoma. Part 1: Diagnostics: Update 2022

Cutaneous melanoma (CM) is potentially the most dangerous form of skin tumor and causes 90% of skin cancer mortality. A unique collaboration of multi-disciplinary experts from the European Dermatology Forum (EDF), the European Association of Dermato-Oncology (EADO) and the European Organization for Research and Treatment of Cancer (EORTC) was formed to make recommendations on CM diagnosis and treatment, based on systematic literature reviews and the experts' experience. The diagnosis of melanoma can be made clinically and shall always be confirmed with dermatoscopy. If a melanoma is suspected, a histopathological examination is always required. Sequential digital dermatoscopy and full body photography can be used in high-risk patients to improve the detection of early melanoma. Where available, confocal reflectance microscopy can also improve clinical diagnosis in special cases. Melanoma shall be classified according to the 8th version of the American Joint Committee on Cancer classification. Thin melanomas up to 0.8 mm tumor thickness do not require further imaging diagnostics. From stage IB onwards, examinations with lymph node sonography are recommended, but no further imaging examinations. From stage IIC onwards whole-body examinations with computed tomography (CT) or positron emission tomography CT (PET-CT) in combination with brain magnetic resonance imaging are recommended. From stage III and higher, mutation testing is recommended, particularly for BRAF V600 mutation. It is important to provide a structured follow-up to detect relapses and secondary primary melanomas as early as possible. There is no evidence to define the frequency and extent of examinations. A stage-based follow-up scheme is proposed which, according to the experience of the guideline group, covers the optimal requirements, but further studies may be considered. This guideline is valid until the end of 2024.

Melanoma: Staging and Follow-Up

Cancer staging is the process determining to which extent a cancer has spread and where it is located in the body. A thorough staging is of utmost importance, not only because it provides the most accurate prognostic estimation, but also because several crucial decisions, such as the treatment choice and the follow-up strategy, vary according to the tumor's stage. The current staging system for melanoma is based on the 8^th edition of TNM classification issued by the American Joint Committee on Cancer (AJCC) in 2017. It includes a clinical and a pathological staging, both consisting of 5 stages (0-IV). The stage of a melanoma is determined by several factors, among which the Breslow thickness, the pathological presence or absence of ulceration in the primary tumor, the presence and the number of tumor-involved regional lymph nodes, the presence or absence of in-transit, satellite and/or microsatellite metastases, and the presence of distant metastases. Following melanoma diagnosis, an accurate medical workup, in line with the stage and the physical examination, should be performed. A continuous patient monitoring is fundamental to detect a potential relapse or a second primary melanoma and should be lifelong. However, there is still no universally adopted follow-up strategy program and different follow-up schemes have been suggested. Future prospective studies are needed to evaluate different follow-up protocols according to the adopted therapy, as novel recent therapies (targeted and immunotherapies) are being increasingly used. Key MessagesProper staging is of utmost importance because it provides accurate prognostic estimation. Several crucial decisions, such as the treatment choice and the follow up strategy, are based on the tumor stage.Physical examination during staging procedure and follow-up visits are important to avoid unnecessary imaging and laboratory tests that could increase the patients' anxiety. A personalized approach taking into consideration the patient's risk factors, is strongly recommended.Melanoma patients should be kept under surveillance lifelong due to an increased risk of developing a second primary melanoma and the risk of recurrence. Higher intensity follow-up strategies during the first 5 years are recommended due to higher rates of regional or distant relapse.