Association of Histologic Regression With a Favorable Outcome in Patients With Stage 1 and Stage 2 Cutaneous Melanoma

The Prognostic Significance of Tumoral Melanosis

BACKGROUND

Tumoral melanosis (TM) is a histological term to describe a nodular aggregation of macrophages containing melanin pigment (melanophages) that is devoid of viable melanocytes. It is most often identified in skin, where it may be appreciated clinically as a pigmented lesion; however, it can also be found in other organs such as lymph nodes. The presence of TM is usually thought to signify the presence of a regressed melanoma or other pigmented tumor. Until recently, it was a relatively uncommon finding; however, with the use of effective systemic therapies against melanoma, its occurrence in histological specimens is more frequent.

METHODS

We identified and reviewed all histopathological diagnoses of TM at any organ site reported at a single institution from 2006 to 2018. TM cases were paired with non-TM cases of cutaneous melanoma through propensity score matching at a 1:2 ratio, and their survival outcomes were compared. The clinical outcomes examined included recurrence-free survival (RFS), distant disease-free survival (DDFS), melanoma-specific survival (MSS), and overall survival (OS).

RESULTS

TM was reported in 79 patients. Their median age was 65 years (range 22-88), with a 2:1 male predominance (51 out of 79, 65%). The most common organ involved was the skin (67%), with a third of all cases localized to a lower limb (36%). TM had a strong association with the presence of melanoma (91%) and regression at other sites of melanoma (54%), suggesting that it is part of a systemic immune response against melanoma. Most patients with TM either previously or subsequently developed histologically confirmed melanoma in the same anatomical region as the TM (89%). Thirty-five TM patients were matched with 70 non-TM cases. Patients with melanoma who developed TM without prior regional or systemic therapy showed improved MSS (p = 0.03), whereas no statistically significant differences were observed in terms of RFS, DDFS, and OS.

CONCLUSIONS

TM usually occurs in the context of a previous or subsequent cutaneous melanoma and is associated with improved MSS. It is important that TM is recognized by pathologists and documented in pathology reports.

Clinical, dermatoscopic, histological and molecular predictive factors of distant melanoma metastasis: A systematic review and meta-analysis

BACKGROUND

Melanoma metastasis to distant sites is associated with diminished survival rates and poor prognosis. Except of Breslow thickness and ulceration that are currently used in melanoma staging, the investigation of additional clinicopathological, dermatoscopic and molecular factors that could predict tumors with aggressive biologic behavior is of paramount importance.

METHODS

A literature search was conducted in PubMed, Scopus, Cochrane databases and gray literature until November 2023. Observational studies (including cohorts and case-control studies) were included and clinical and histopathological factors of primary cutaneous melanomas, along with dermatoscopic and molecular predictors of distant metastasis (DM) and distant metastasis-free survival (DMFS) were assessed. Random - effect models were preferred, the results were presented as Hazard Ratios (HRs) with 95 %Confidence Intervals (CIs) and the I2 index quantified heterogeneity. Subgroup analysis according to AJCC stage and sensitivity analysis were also conducted.

RESULTS

One hundred forty-three and 101 studies were included in the qualitive and quantitative synthesis, respectively. Regarding clinical factors, males, compared to females, and head and neck location, compared to trunk, demonstrated higher risk for DM [n=36, HR 1.49, 95%CI 1.36 - 1.63, I2 33% and n=21, HR 1.24, 95 %CI 1.01 - 1.52, I2 62 %]. Both factors had similar effects on DMFS. Breslow thickness and ulceration were significant predictors or DM. Additional factors that posed an increased risk for DM were nodular (n=15, HR 2.51, 95 %CI 1.83 - 3.43, I2 56 %) and lentigo maligna subtypes (n=12, HR 1.87, 95 %CI 1.27 - 2.75, I2 0 %), compared to superficial spreading subtype, lymphovascular invasion (n=9, HR 2.05, 95 %CI 1.18 - 3.58, I2 78 %), SLN positivity and BRAF+ mutational status. In contrast, regression was a negative predictor of DM (n=15, HR 0.59, 95 %CI 0.44 - 0.79, I2 68 %). Two studies focused on dermatoscopic factors and found that low pigmentation and the presence of blue-white veil might predict DM development. The results of subgroup analysis for stage I-II patients were essentially similar and sensitivity analysis did not reveal significant alterations, despite the moderate or high heterogeneity in some categories.

CONCLUSIONS

Clinical and histological characteristics of the tumor along with dermatoscopic features and molecular parameters hold significant prognostic information and could be incorporated into models to predict melanomas with high metastatic potential.

Development of a prognostic model for patients with nodular melanoma of the lower extremities: a study based on the SEER database

Lower extremity nodular melanoma (NM) is a common malignant tumor with a poor prognosis. We aims to identify the prognostic factors and develop a nomogram model to predict overall survival (OS) in patients with lower extremity NM. A total of 746 patients with lower extremity NM were selected and randomly divided into a training set (522 cases) and a validation set (224 cases) from the Surveillance, Epidemiology, and End Results(SEER) database. The training set underwent univariate and multivariate Cox regression analyses to identify independent prognostic factors associated with patient outcomes, and to develop a nomogram model. The effectiveness of the nomogram was subsequently validated using the validation set. Multivariable Cox regression analysis of the training set indicated that age, ulceration, radiotherapy, chemotherapy, primary site of first malignant tumor, and Breslow thickness were independent variables associated with OS. In the training set, the area under the curve (AUC) of the nomogram for predicting 3-year and 5-year OS was 0.796 and 0.811, respectively. In the validation set, the AUC for predicting 3-year and 5-year OS was 0.694 and 0.702, respectively. The Harrell's C-index for the training set and validation set were 0.754 (95% CI: 0.721-0.787) and 0.670 (95% CI: 0.607-0.733), respectively. Calibration curves for both training and validation sets showed good agreement. In this study, we develop and validate a nomogram to predict OS in patients with lower extremity NM. The nomogram demonstrated reasonable reliability and clinical applicability. Nomograms are important tools assessing prognosis and aiding clinical decision-making.

Optimizing time prediction and error classification in early melanoma detection using a hybrid RCNN-LSTM model

Skin cancer is a terrifying disorder that affects all individuals. Due to the significant increase in the rate of melanoma skin cancer, early detection of skin cancer is now more critical than ever before. Malignant melanoma is one of the most serious forms of skin cancer, and it is caused by abnormal melanocyte cell growth. In recent years, skin cancer predictive categorization has become more accurate and predictive due to multiple deep learning algorithms. Malignant melanoma is diagnosed using the Recurrent Convolution Neural Network-Long Short-Term Memory (RCNN-LSTM), which is one of the deep learning classification approaches. Using the International Skin Image Collection and the RCNN-LSTM, the data are categorized and analyzed to gain a better understanding of skin cancer. The method begins with data preprocessing, which prepares the dataset for classification. Additionally, the RCNN is employed to extract the features that are vital to the prediction process. The LSTM is accountable for the final step, classification. There are further factors to examine, such as the precision of 94.60%, the sensitivity of 95.67%, and the F1-score of 95.13%. Other benefits of the suggested study include shorter prediction durations of 95.314, 122.530, and 131.205 s and lower model loss of 0.25%, 0.19%, and 0.15% for input sizes 10, 15, and 20, respectively. Three datasets had a reduced categorization error of 5.11% and an accuracy of 95.42%. In comparison to previous approaches, the work discussed here produces superior outcomes. RESEARCH HIGHLIGHTS: Recurrent convolutional neural network (RCNN) deep learning approach for optimizing time prediction and error classification in early melanoma detection. It extracts a high number of specific features from the skin disease image, making the classification process easier and more accurate. To reduce classification errors in accurately detecting melanoma, context dependency is considered in this work. By accounting for context dependency, the deprivation state is avoided, preventing performance degradation in the model. To minimize melanoma detection model loss, a skin disease image augmentation or regularization process is performed in this work. This strategy improves the accuracy of the model when applied to fresh, previously unobserved data.

Acute regression of a melanocytic neoplasm

Immune-mediated regression of melanocytic neoplasms is predominantly lymphocytic, driven by CD8+ anti-tumoral T-cells and, rarely, natural killer cells. Histopathologic features of regression include effacement of the epidermis, replacement of tumor cells by a fibrotic stroma, varying degrees of chronic inflammation (usually lymphocytes) and melanophages, as well as vascular ectasia and angioplasia. The understanding of regression and the complex immune response in melanoma has led to the development of targeted immunotherapy in melanoma. Here, we report a case of near-complete regression of a melanocytic neoplasm associated with neutrophilic and eosinophilic inflammation, suggesting a non-traditional pathway of regression that has yet to be explored.

Regression in cutaneous melanoma: histological assessment, immune mechanisms and clinical implications

Tumour regression is an immunologically driven process that results in complete or partial disappearance of tumour cells. This can be observed in histological sections as replacement of tumour cells with fibrosis, angiogenesis, and a variable inflammatory infiltrate. In primary cutaneous melanoma, the prognostic significance of regression has been debated for decades, in part because inconsistent histological criteria are used in prognostication studies. It is broadly accepted that CD8+ T lymphocytes are the primary effectors of the anti-tumour response, but the interplay between melanoma and the immune system is complex, dynamic, and incompletely understood. Sustained progress in unravelling the pathogenesis of melanoma regression has led to the identification of therapeutic targets, culminating in the development of immune checkpoint inhibitors for the management of advanced disease. Modern techniques allow for high-resolution spatial analyses of the tumour microenvironment. Such studies may lead to better understanding of the immune drivers of melanoma regression, thereby facilitating the search for new prognostic and predictive biomarkers to assist clinical decision-making.

Polypoid Malignant Melanoma with Spontaneous Decapitation Showing Favorable Prognosis: A Case Report

Introduction

Regression of malignant melanoma (MM) is a commonly observed phenomenon, which refers to disappearance or loss of all or part of MM. It can be identified both clinically and histologically, and high probability of histological regression of MM (10-58%) has been reported. However, the decapitation of skin tumor has rarely been described in the English literature, and decapitation in MM has not been reported. Here, we report the case of polypoid MM with spontaneous decapitation.

Case Presentation

An 81-year-old Japanese woman was referred to our hospital due to a polypoid nodule on her cheek. She was diagnosed with MM at stage IIC (T4bN0M0) by histological examinations. Three weeks after the biopsy, the nodule decapitated spontaneously without bleeding, and an ulcer developed on the base of the polypoid nodule. The histological examination of the additionally resected ulcerative lesion under the nodule revealed infiltration of T cells mainly composed of CD8⁺ natural killer T cells. No recurrence or metastasis has been observed for 4 years.

Conclusion

This is the first case report of polypoid MM with spontaneous decapitation, which may be attributed to natural killer T cells. Moreover, this case shows favorable prognosis, while it is said that the regression in thick MM does not have prognostic advantage and polypoid topography has been reported to be related to extremely poor prognosis. Further investigations are needed to evaluate the prognostic advantage of decapitation in MM and other skin tumors.

Prognostic model for predicting overall and cancer-specific survival among patients with superficial spreading melanoma: A SEER based study

Skin malignant melanoma is one of the most aggressive skin tumors. Superficial spreading melanoma (SSM) is the most common histological type, which can originate from different body skin sites, and some patients can still accumulate regional lymph nodes and even have distant metastasis in some cases. This study used the relevant data from the monitoring, epidemiology and results database of the National Cancer Institute database to study the overall survival (OS) and cancer-specific survival (CSS) of SSM patients and established an SSM nomogram to evaluate the prognosis of patients. A total of 13,922 patients were collected from the monitoring, epidemiology and results database of the National Cancer Institute and randomly divided into a training cohort (8353 cases) and a validation cohort (5569 cases). Univariate and multivariate Cox regression analysis were used to determine prognostic factors, and these factors were used to construct OS and CSS nomograms for patients with SSM. Finally, the discrimination and consistency of the nomogram model were evaluated by the consistency index (C-index), area under the curve (AUC) and calibration curve. Multivariate Cox regression analysis suggested that age, sex, tumor site, the American joint committee on cancer T stage and the first primary melanoma were independent predictors of OS and CSS in patients with SSM and that the American joint committee on cancer N stage was also an independent predictor of CSS in patients with SSM. Based on the above prognostic factors, this study constructed a predictive model. The C-index of the model OS and CSS for this training cohort was 0.805 [95% CI: 0.793-0.817] and 0.896 [95% CI: 0.878-0.913], respectively. The AUC values for 1-, 3-, and 5-year OS were 0.822, 0.820, and 0.821, respectively, and the AUC values for CSS were 0.914, 0.922, and 0.893, respectively. The data indicated that both nomograms showed better predictive accuracy. The calibration curves of the training cohort and the validation cohort were in good agreement. The nomogram has superior predictive performance in predicting 1-, 3-, and 5-year OS and CSS prognosis in patients with SSM and can provide a reference for individualized treatment and clinical counseling of SSM.

Survival analysis in head and neck melanoma after negative sentinel lymph node biopsy: A seer-based population study

BACKGROUND

Cutaneous malignant melanoma (CMM) is one of the most aggressive skin tumors. Sentinel lymph node biopsy (SLNB) is an important test before thorough treatment of melanoma. The aim of this study was to investigate cancer-specific survival (CSS) in patients with head and neck CMM after negative SLNB and to analyze predictors of decreased survival.

METHODS

Based on the Surveillance, Epidemiology and End Results (SEER) database, a study was conducted using data from patients with head and neck CMM after negative SLNB. The demographic, clinical, and pathological characteristics of the case population were analyzed. Cox univariate, Kaplan-Meier analysis, and multivariate Cox regression models were used to explore predictors of decreased survival; propensity score matching (PSM) analysis was used to reduce confounding bias, and outcomes were compared between the wide margin excision and narrow margin excision groups.

RESULTS

A total of 1597 confirmed head and neck CMM patients with SLNB-negative were found. A Breslow>4.0 mm was the highest independent risk predictor for patients (HR 3.82, 95% CI 2.04-7.16, P < .001), and significant risk independent predictors also included a high mitotic rate >4 (HR 1.54, 95% CI 1.06-2.25, P = .023). Age< 60 years old was a significant survival predictor (HR 0.56, 95% CI .37-.85, P = .007), and not scalp and neck CMM were also important factors for longer survival (auricle skin: HR .51, 95% CI .29-.90, P = .02; unspecified parts of face: HR .59, 95% CI .40-.87, P = .007). After harmonizing baseline data by PSM, it was found that the extent of surgical resection did not affect patient survival.

CONCLUSION

This study analyzed the risk factors affecting CSS in patients with CMM of the head and neck region with SLNB-negative and observed a statistically significant difference in the prognosis of patients with CMM in different aesthetic subunits of the head and neck region. Close clinical follow-up for this population is necessary, and periodic medical examinations should be carried out.

American Joint Committee on Cancer (AJCC) tumor staging system predicts the outcome and metastasis pattern in conjunctival melanoma

PURPOSE

To assess the predictive value of the tumor staging system in the eighth edition of the American Joint Committee on Cancer Cancer Staging Manual (AJCC 8th-Edition) and histologic features for outcomes and metastasis patterns in conjunctival melanoma (CM).

DESIGN

Retrospective, single-center cohort study.

PARTICIPANTS

Eighty-three patients with CM were treated at our center between 2000 and 2021.

METHODS

We reviewed clinical and histopathological parameters and used Kaplan-Meier survival curves and Cox proportional hazards regression models for risk factor analyses.

MAIN OUTCOME MEASURES

Time to nodal/distant metastasis, disease-specific survival, metastatic pattern, and metastatic site.

RESULTS

At presentation, five patients (6%) had cT1 disease, 34 (41%) had cT2 disease, and 44 (53%) had cT3 disease. Four (5%) patients had nodal metastasis (N1), and none had distant metastasis (M1). During follow-up, 12 (14%) developed nodal metastasis, 29 (35%) developed distant metastasis, and 26 (31%) died of disease. Brain, liver and lung were common distant metastasis sites. Higher cT category was associated with increased risks of distant metastasis (p<0.001) and disease-specific death (p=0.002). The separate analysis of primary and recurrent tumors at presentation showed that the patients with cT3 tumors took a much higher risk of distant metastasis than those with cT2 tumors. Greater tumor thickness, ulceration, and the presence of regression were correlated with distant metastasis. Previously unreported mutations were detected in the tumor suppressor genes: FAT4 and SYK. Among the 29 patients who developed distant metastasis, we analyzed two patterns of metastasis: 11 patients (38%) developed nodal metastasis prior to distant metastasis, and 18 patients (62%) developed distant metastasis without previously known nodal metastasis. The patients with cT3 tumors were more likely to follow the latter metastasis pattern (p=0.02).

CONCLUSION

CM presented with mostly advanced stages and high rates of distant metastasis in the current Chinese cohort. This study confirmed the prognostic value of the tumor staging system in the AJCC 8th-Edition in Chinese patients. Histologic features, such as tumor thickness and ulceration, should be emphasized when assessing prognosis and guiding the treatment of CM.

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.

Interobserver Agreement on Dermoscopic Features and their Associations with In Situ and Invasive Cutaneous Melanomas

Several melanoma-specific dermoscopic features have been described, some of which have been reported as indicative of in situ or invasive melanomas. To assess the usefulness of these features to differentiate between these 2 categories, a retrospective, single-centre investigation was conducted. Dermoscopic images of melanomas were reviewed by 7 independent dermatologists. Fleiss' kappa (κ) was used to analyse interobserver agreement of predefined features. Logistic regression and odds ratios were used to assess whether specific features correlated with melanoma in situ or invasive melanoma. Overall, 182 melanomas (101 melanoma in situ and 81 invasive melanomas) were included. The interobserver agreement for melanoma-specific features ranged from slight to substantial. Atypical blue-white structures (κ=0.62, 95% confidence interval 0.59-0.65) and shiny white lines (κ=0.61, 95% confidence interval 0.58-0.64) had a substantial interobserver agreement. These 2 features were also indicative of invasive melanomas >1.0 mm in Breslow thickness. Furthermore, regression/peppering correlated with thin invasive melanomas. The overall agreement for classification of the lesions as invasive or melanoma in situ was moderate (κ=0.52, 95% confidence interval 0.49-0.56).

Finding reduced Raman spectroscopy fingerprint of skin samples for melanoma diagnosis through machine learning

Early-stage detection of cutaneous melanoma can vastly increase the chances of cure. Excision biopsy followed by histological examination is considered the gold standard for diagnosing the disease, but requires long high-cost processing time, and may be biased, as it involves qualitative assessment by a professional. In this paper, we present a new machine learning approach using raw data for skin Raman spectra as input. The approach is highly efficient for classifying benign versus malignant skin lesions (AUC 0.98, 95% CI 0.97-0.99). Furthermore, we present a high-performance model (AUC 0.97, 95% CI 0.95-0.98) using a miniaturized spectral range (896-1039 cm^-1), thus demonstrating that only a single fragment of the biological fingerprint Raman region is needed for producing an accurate diagnosis. These findings could favor the future development of a cheaper and dedicated Raman spectrometer for fast and accurate cancer diagnosis.

Regression in melanoma is significantly associated with a lower regional recurrence rate and better recurrence-free survival

BACKGROUND AND OBJECTIVES

The prognostic significance of regression in predicting melanoma recurrences is unknown. We present a large multicenter study correlating regression with recurrence.

METHODS

The Sentinel Lymph Node Working Group database was queried from 1993 to 2018 for cases with regression data. Clinicopathologic factors were correlated with overall and first-site of recurrence and with recurrence-free survival (RFS).

RESULTS

There were 4790 patients and the median follow-up was 39.6 months. Regression and recurrences were seen in 1081 (22.6%) and 773 (16.1%) cases, respectively. First-site locoregional and distant recurrences were seen in 412 (8.6%) and 352 (7.3%) patients, respectively. Regression was seen in 15.8% and 24.7% of all cases with and without recurrences (p < 0.0001), respectively, while regression was seen in 14.3% and 17.9% of first-site locoregional and distant recurrent cases, respectively, compared with 23.3% and 22.9% of patients with regression and without first-site locoregional and distant recurrences, respectively (p = 0.29). On multivariable analysis, after controlling for age, gender, thickness, ulceration, lymphovascular invasion, and sentinel lymph node status, regression significantly predicted improved RFS (p = 0.004) and fewer first-site regional recurrences (p = 0.017).

CONCLUSION

Our data suggest that regression is a favorable prognostic marker in melanoma and predicts significantly better RFS and decreased first-site regional recurrences.

Nomogram Incorporating the WNT/β-Catenin Signaling Pathway for Predicting the Survival of Cutaneous Melanoma

Background

Accurate prediction of the survival of cutaneous melanoma (CM) permits the selection of the optimal treatment. Currently, the TNM stage has limitations in predicting the survival of CM. There is evidence that the WNT/β-catenin signaling pathway has the potential to predict the CM prognosis. However, it still needs further investigation.

Objective

This study aims to establish a nomogram incorporating the WNT/β-catenin signaling pathway to improve the predicted accuracy of the overall survival (OS) of CM.

Methods

Two hundred and eighty CM patients were recruited and followed up. The clinicopathological characteristics and the key genes of the WNT/β-catenin signaling pathway (VEGF, β-catenin, and DKK1) were chosen as potential variables associated with the OS. In the training cohort (n = 190), a nomogram was built to estimate the 1-, 3-, and 5-year OS, and its discriminations and calibrations were valid by the verification cohort (n = 90). The predicted accuracies of the nomogram with or without the Wnt/β-catenin pathway and TNM stage were compared.

Results

A nomogram integrating independent risk factors (ulceration, lymph node metastasis, distant metastasis, Breslow thickness, dermal mitoses, β-catenin, VEGF, and DKK1), which were evaluated by a multivariate analysis, was constructed to predict the 1-, 3-, and 5-year OS of CM patients. Good discrimination and calibration were obtained regardless of the training or validation datasets. The nomogram incorporating the Wnt/β-catenin signaling pathway showed the highest accuracy [area under the curve (AUC)=0.914, 0.852, 0.785] compared with the nomogram without the Wnt/β-catenin signaling pathway (AUC=0.693, 0.640, 0.615) and the TNM stage (AUC=0.726, 0.693, 0.673).

Conclusion

The prognostic value of the established nomogram incorporating the WNT/β-catenin signaling pathway was better than it without WNT/β-catenin signaling pathway and TNM stage, which might be beneficial in the development of optimal treatment options.

Regression is significantly associated with outcomes for patients with melanoma

BACKGROUND

The prognostic significance of regression in melanoma is debated. We present a large multicenter study correlating regression with sentinel lymph node metastasis and melanoma-specific survival.

METHODS

The Sentinel Lymph Node Working Group database was reviewed from 1993 to 2018. Patients with known regression and sentinel lymph node status were included. Clinicopathologic factors were correlated with regression, sentinel lymph node status, and melanoma-specific survival.

RESULTS

There were 4,790 patients; median follow-up was 39.6 months. Regression was present in 1,081 (22.6%) cases, and 798 (16.7%) patients had sentinel lymph node metastases. On multivariable analysis, male sex, truncal tumors, and decreasing thickness were significantly associated with regression (P < .05), whereas head/neck or leg tumors had lower rates of regression (P < .05). Regression was significantly correlated with a decreased risk of sentinel lymph node disease on multivariable analysis (odds ratio 0.68, 95% confidence interval 0.54-0.85; P = .0008). Multivariable analysis also showed that increasing age, male sex, increasing thickness, ulceration, lymphovascular invasion, microsatellitosis, and sentinel lymph node metastasis were significantly (P < .05) associated with worse melanoma-specific survival, while regression was significantly associated with better melanoma-specific survival (hazard ratio 0.75, 95% confidence interval 0.57-0.99; P = .043).

CONCLUSION

This large study shows that regression is significantly associated with better outcomes in patients with melanoma and is correlated with a lower risk of sentinel lymph node metastasis and a better melanoma-specific survival.

Histopathologic synoptic reporting of invasive melanoma: How reliable are the data?

BACKGROUND

Synoptic reporting is recommended by many guideline committees to encourage the thorough histologic documentation necessary for optimal management of patients with melanoma.

METHODS

One hundred fifty-one pathologists from 40 US states interpreted 41 invasive melanoma cases. For each synoptic reporting factor, the authors identified cases with "complete agreement" (all participants recorded the same value) versus any disagreement. Pairwise agreement was calculated for each case as the proportion of pairs of responses that agreed, where paired responses were generated by the comparison of each reviewer's response with all others.

RESULTS

There was complete agreement among all reviewers for 22 of the 41 cases (54%) on Breslow thickness dichotomized at 0.8 mm, with pairwise agreement ranging from 49% to 100% across the 41 cases. There was complete agreement for "no ulceration" in 24 of the 41 cases (59%), with pairwise agreement ranging from 42% to 100%. Tumor transected at base had complete agreement for 26 of the 41 cases (63%), with pairwise agreement ranging from 31% to 100%. Mitotic rate, categorized as 0/mm² , 1/mm² , or 2/mm² , had complete agreement for 17 of the 41 cases (41%), with pairwise agreement ranging from 36% to 100%. Regression saw complete agreement for 14 of 41 cases (34%), with pairwise agreement ranging from 40% to 100%. Lymphovascular invasion, perineural invasion, and microscopic satellites were rarely reported as present. Respectively, these prognostic factors had complete agreement for 32 (78%), 37 (90%), and 18 (44%) of the 41 cases, and the ranges of pairwise agreement were 47% to 100%, 70% to 100%, and 53% to 100%, respectively.

CONCLUSIONS

These findings alert pathologists and clinicians to the problem of interobserver variability in recording critical prognostic factors.

LAY SUMMARY

This study addresses variability in the assessment and reporting of critical characteristics of invasive melanomas that are used by clinicians to guide patient care. The authors characterize the diagnostic variability among pathologists and their reporting methods in light of recently updated national guidelines. Results demonstrate considerable variability in the diagnostic reporting of melanoma with regard to the following: Breslow thickness, mitotic rate, ulceration, regression, and microscopic satellites. This work serves to alert pathologists and clinicians to the existence of variability in reporting these prognostic factors.