The Implications of a Dermatopathologist's Report on Melanoma Diagnosis and Treatment

An accurate and comprehensive histopathology report is essential for cutaneous melanoma management, providing critical information for accurate staging and risk estimation and determining the optimal surgical approach. In many institutions, a review of melanoma biopsy specimens by expert dermatopathologists is considered a necessary step. This study examined these reviews to determine the critical primary histopathology Breslow score in which a histopathology review would be most beneficial. Histopathology reports of patients referred to our institute between January 2011 and September 2019 were compared with our in-house review conducted by an expert dermatopathologist. The review focused on assessing fundamental histologic and clinical prognostic features. A total of 177 specimens underwent histopathology review. Significant changes in the Breslow index were identified in 103 cases (58.2%). Notably, in many of these cases (73.2%), the revised Breslow was higher than the initially reported score. Consequently, the T-stage was modified in 51 lesions (28.8%). Substantial discordance rates were observed in Tis (57%), T1b (59%), T3a (67%) and T4a (50%) classifications. The revised histopathology reports resulted in alterations to the surgical plan in 15.3% of the cases. These findings emphasize the importance of having all routine pathologies of pigmented lesions referred to a dedicated cancer center and reviewed by an experienced dermatopathologist. This recommendation is particularly crucial in instances where the histopathology review can potentially alter the diagnosis and treatment plan, such as in melanoma in situ and thinner melanomas measuring 0.6-2.2 mm in thickness. Our study highlights the significant impact of histopathology reviews in cutaneous melanoma cases. The observed changes in Breslow scores and subsequent modifications in T-stage classification underline the need for thorough evaluation by an expert dermatopathologist, especially in cases of melanoma in situ and thin melanomas. Incorporating such reviews into routine practice within dedicated cancer centers can improve diagnostic accuracy and guide appropriate treatment decisions, ultimately leading to better patient outcomes.

Impact of second histopathological review of melanocytic skin lesions at a melanoma reference center in Brazil

BACKGROUND

After the biopsy of a suspicious melanocytic lesion, patients depend on the pathologist's precision of specimen evaluation.

METHODS

We assessed the agreement between histopathological reports made by general pathologists and reviewed by a dermatopathologist to evaluate the impact on the patient's management.

RESULTS

In 79 cases analyzed, underdiagnosis was observed in 21.6% and overdiagnosis in 17.7%, resulting in changes in the patients' conduct. The assessment of the Clark level, ulceration and histological type showed mild agreement (P<0.001); the Breslow thickness, surgical margin, and staging showed moderate agreement (P<0.001).

CONCLUSIONS

A dermatopathologist's review should be incorporated into the routine of reference services for pigmented lesions.

Predictive Values of Pathological and Clinical Risk Factors for Positivity of Sentinel Lymph Node Biopsy in Thin Melanoma: A Systematic Review and Meta-Analysis

Background

The indications for sentinel lymph node biopsy (SLNB) for thin melanoma are still unclear. This meta-analysis aims to determine the positive rate of SLNB in thin melanoma and to summarize the predictive value of different high-risk features for positive results of SLNB.

Methods

Four databases were searched for literature on SLNB performed in patients with thin melanoma published between January 2000 and December 2020. The overall positive rate and positive rate of each high-risk feature were calculated and obtained with 95% confidence intervals (CIs). Both unadjusted odds ratios (ORs) and adjusted ORs (AORs) of high-risk features were analyzed. Pooled effects were estimated using random-effects model meta-analyses.

Results

Sixty-six studies reporting 38,844 patients with thin melanoma who underwent SLNB met the inclusion criteria. The pooled positive rate of SLNB was 5.1% [95% confidence interval (CI) 4.9%-5.3%]. Features significantly predicted a positive result of SLNB were thickness≥0.8 mm [AOR 1.94 (95%CI 1.28-2.95); positive rate 7.0% (95%CI 6.0-8.0%)]; ulceration [AOR 3.09 (95%CI 1.75-5.44); positive rate 4.2% (95%CI 1.8-7.2%)]; mitosis rate >0/mm2 [AOR 1.63 (95%CI 1.13-2.36); positive rate 7.7% (95%CI 6.3-9.1%)]; microsatellites [OR 3.8 (95%CI 1.38-10.47); positive rate 16.6% (95%CI 2.4-36.6%)]; and vertical growth phase [OR 2.76 (95%CI 1.72-4.43); positive rate 8.1% (95%CI 6.3-10.1%)].

Conclusions

The overall positive rate of SLNB in thin melanoma was 5.1%. The strongest predictor for SLN positivity identified was microsatellites on unadjusted analysis and ulceration on adjusted analysis. Breslow thickness ≥0.8 mm and mitosis rate >0/mm² both predict SLN positivity in adjusted analysis and increase the positive rate to 7.0% and 7.7%. We suggest patients with thin melanoma with the above high-risk features should be considered for giving an SLNB.

Immunostained Frozen Sections Vs Traditional Permanent Paraffin Sections for Lentigo Maligna Treated With Mohs Micrographic Surgery

BACKGROUND

Mohs micrographic surgery (MMS) has risen in popularity as a management option for treating lentigo maligna (LM) because of its ability to accurately detect subclinical spread while conserving tissue. The primary concern for opponents of MMS in melanoma remains the difficulty associated with interpretation of frozen sections compared with traditional paraffin sections; this has been made easier with the advent of immunostaining.

OBJECTIVE

Our study aims to assess the concordance in clearance reporting of LM in immunostained frozen sections compared with permanent paraffin sections and hematoxylin and eosin staining.

METHODS

We conducted a retrospective analysis of 38 LM cases treated by MMS between 2017 and 2020 in Melbourne, Australia. Immunostained frozen sections were assessed by a Mohs surgeon, whereas permanent paraffin sections were assessed by an external dermatopathologist.

RESULTS

We report 86% agreement in reporting of LM in immunostained frozen sections compared with permanent paraffin sections. In 5/38 cases, permanent paraffin sections were reported as clear for LM, but the Mohs surgeon had detected positive margins, requiring further excision.

CONCLUSION

For LM treated with MMS, there is a high agreement of clearance reporting between immunostained stained frozen sections and permanent paraffin sections without immunostaining; however, immunostained frozen sections may be more sensitive.

In-vivo imaging of melanoma with simultaneous dual-wavelength acoustic-resolution-based photoacoustic/ultrasound microscopy

Melanoma is a common, highly fatal skin cancer. Photoacoustic imaging can achieve highly sensitive and high-contrast detection of melanin molecules in tissues, also inheriting the high penetration depth and high spatial resolution characteristics of ultrasound imaging, thus it is a very promising non-invasive diagnostic tool for early melanoma. In this work, we built an acoustic-resolution-based photoacoustic microscopy system, using 1064 nm/532 nm pulsed light to observe melanoma in the back of a mouse with simultaneous photoacoustic/ultrasound imaging. Through the fusion of multi-modal images, accurate positioning of melanoma and its surrounding normal tissues were realized. This work will further promote the application of photoacoustic imaging in the clinical diagnosis of early melanoma.

Clinicopathological, immunohistochemical and fluorescence in-situ hybridisation features of early subungual melanoma: an analysis of 65 cases

AIMS

Very limited data are available concerning the clinicopathological and molecular features of early subungual melanoma (SM), especially with regard to the Asian population. The aim of this study was to investigate the clinical, histological, immunohistochemical and chromosomal features of early SM.

METHODS AND RESULTS

Fifty-two in-situ and 13 thin (Breslow thickness ≤1.0 mm) SM cases were retrospectively reviewed. All patients presented with longitudinal melanonychia involving a single digit, and the thumb was the most affected digit (35 of 65, 53.8%). Microscopically, most cases showed small to medium nuclear enlargement (58 of 65) and mild to moderate nuclear atypia (57 of 65). Hyperchromatism and irregular contours of nuclei were persistent features in all cases. The variation of melanocyte count (the number of melanocytes per mm dermal-epithelial junction) ranged from 31 to 255. Intra-epithelial mitoses were identified in 34 cases (52.3%). Statistically, features of in-situ lesions including higher melanocyte count (>70), presence of multinucleated melanocytes, inflammatory infiltrate and cutaneous adnexal extension, were associated with early invasion. Melan-A, human melanoma B (HMB)45, mouse monoclonal melanoma antibody (PNL2) and SOX10 antibodies (>95.0%) showed superior diagnostic sensitivity to S-100 protein (83.1%). Fluorescence in-situ hybridisation (FISH) results were positive in 15 of 23 successfully analysed cases.

CONCLUSIONS

To the best of our knowledge, this is the largest single-institution study of early SM in an Asian population, and the largest cohort tested by FISH. Early SM mainly showed small to medium nuclear enlargement and mild to moderate nuclear atypia. High melanocyte count, hyperchromatism and irregular contours of nuclei and intra-epithelial mitoses are crucial diagnostic parameters. Immunohistochemistry, especially SOX10 staining, and FISH analysis are valuable in the diagnosis of SM.

Patterns of Multidisciplinary Care of Head and Neck Squamous Cell Carcinoma in Medicare Patients

Importance

Multidisciplinary care (MDC) yields proven benefits for patients with cancer, although it may be underused in the complex management of head and neck squamous cell carcinoma (HNSCC).

Objective

To characterize the patterns of MDC in the treatment of HNSCC among elderly patients in the US.

Design, Setting, and Participants

This nationwide, population-based, retrospective cohort study used Surveillance, Epidemiology, and End Results (SEER)-Medicare linked data from January 1, 1991, to December 31, 2011, to identify patients 66 years or older diagnosed with head and neck cancer and determine the dates of diagnosis, oncology consultations, treatment initiation, and speech therapy evaluation in addition to MDC completion. Multidisciplinary care was defined in a stage-dependent manner: localized disease necessitated consultations with radiation and surgical oncologists, and advanced-stage disease also included a medical oncology consultation, all before definitive treatment. Data were analyzed between December 2016 and September 2020.

Main Outcomes and Measures

Rates of MDC across all subsites of head and neck cancer as measured by the presence of an evaluation for each oncologist on the MDC team and its effect on treatment initiation.

Results

This cohort study assessed 28 293 patients with HNSCC (mean [SD] age, 75.1 [6.6] years; 67% male; 87% White) from the SEER-Medicare linked database. The HNSCC subsites included larynx (40%), oral cavity (30%), oropharynx (21%), hypopharynx (7%), and nasopharynx (2%). Overall, the practice of MDC significantly increased over time, from 24% in 1991 to 52% in 2011 (P < .001). For patients with localized (stage 0-II) tumors, 60% received care in the multidisciplinary setting, whereas 28% of those with advanced-stage disease did. A total of 18 181 patients (64%) were treated with initial definitive nonsurgical therapy across all stages. Regardless of stage and subsite, few patients (2%) underwent evaluation by a speech-language pathologist before definitive therapy. Multidisciplinary care prolonged the time to initiation of definitive treatment by 11 days for localized disease and 10 days for advanced disease.

Conclusions and Relevance

This cohort study found that most elderly patients with localized HNSCC received MDC, whereas few patients with advanced-stage disease received such care, although a significant proportion received adjuvant therapy. Multidisciplinary care may prolong time to initiation of definitive treatment with an uncertain impact. Consultation with a speech-language pathologist before definitive therapy was rare.

Challenges in sentinel node pathology in the era of adjuvant treatment

BACKGROUND

With the approval of adjuvant therapy for stage III melanoma, accurate staging is more important than ever. Sentinel node biopsy (SNB) is an accurate staging tool, yet the presence of capsular nevi (CN) can lead to a false-positive diagnosis.

PATIENTS AND METHODS

Retrospective analysis of the American Joint Committee on Cancer 7th edition stage IIIA melanoma patients who were treated at our institute between 2000 and 2015. SNB slides were reviewed for this study by an expert melanoma pathologist.

RESULTS

Of 159 eligible patients, 14 originally diagnosed with metastatic melanoma merely had CN (8.8%). Another two merely had melanophages (1.3%). Thus, 10.1% of SNs were considered false positive after revision. In 12 patients, the SN tumor burden was originally reported as larger than 1 mm but turned out to be less than 1 mm. Four patients originally reported as SN tumor burden less than 1 mm before revision turned out to have larger than 1 mm. These patients might have been over- or undertreated in the current era of adjuvant therapy for stage III melanoma.

CONCLUSIONS

Distinguishing metastatic melanoma from benign CN and melanophages can be a diagnostic challenge. We plead for an expert pathologists' review, especially when using the SNB + results to determine treatment consequences.

Molecular risk prediction in cutaneous melanoma: A meta-analysis of the 31-gene expression profile prognostic test in 1,479 patients

BACKGROUND

Multiple studies have reported on the accuracy of the prognostic 31-gene expression profile test for cutaneous melanoma. Consistency of the test results across studies has not been systematically evaluated.

OBJECTIVE

To assess the robustness of the prognostic value of the 31-gene expression profile.

METHODS

Raw data were obtained from studies identified from systematic review. A meta-analysis was performed to determine overall effect of the 31-gene expression profile. Clinical outcome metrics for the 31-gene expression profile were compared with American Joint Committee on Cancer staging.

RESULTS

Three studies met inclusion criteria; data from a novel cohort of 211 patients were included (n = 1,479). Five-year recurrence-free and distant metastasis-free survival rates were 91.4% and 94.1% for Class 1A patients and 43.6% and 55.5% for Class 2B patients (P < .0001). Meta-analysis results showed that Class 2 was significantly associated with recurrence (hazard ratio 2.90; P < .0001) and distant metastasis (hazard ratio 2.75; P < .0001). The 31-gene expression profile identified American Joint Committee on Cancer stage I to III patient subsets with high likelihood for recurrence and distant metastasis. Sensitivity was 76% (95% confidence interval 71%-80%) and 76% (95% confidence interval 70%-82%) for each end point, respectively. When 31-gene expression profile and sentinel lymph node biopsy results were considered together, sensitivity and negative predictive value for distant metastasis-free survival were both improved.

CONCLUSION

The 31-gene expression profile test consistently and accurately identifies melanoma patients at increased risk of metastasis, is independent of other clinicopathologic covariates, and augments current risk stratification by reclassifying patients for heightened surveillance who were previously designated as being at low risk.

Internal Pathology Review of Invasive Melanoma: An Academic Institution Experience

BACKGROUND

Prior studies of internal pathology review (IPR) for melanoma have shown that changes in the pathology analysis are common. How these changes impact clinical management of melanoma or how the margin status reports may modify has not been evaluated. Our goal was to determine what changes to staging and surgical management occurred after IPR of newly diagnosed melanomas and to determine how the final surgical pathology report may correlate with the IPR.

METHODS

A retrospective study was conducted from 2014 to 2016 of newly diagnosed invasive melanomas referred to a single National Comprehensive Cancer Network tertiary care center.

RESULTS

A total of 370 cases met inclusion criteria. The most common feature changed after internal review was mitotic rate, in 155 (41.7%) patients, followed by Breslow depth in 99 (26.9%) patients. Tumor staging was changed in 45 (12.2%) patients. The most common change was a T1a lesion being upgraded to a T1b lesion. These tumor staging changes lead to 38 (10.3%) overall staging differences. A biopsy's deep margin status was changed in 27 (7.3%) patients. Outside hospital reports lacked information about deep margin status in 71 (19.2%) of specimens. Based on the National Comprehensive Cancer Network guidelines, 22 (5.9%) patients had changes in their sentinel lymph node biopsy recommendations and one of these patients had a positive node found on pathology. Of those patients who had changes in the T-stage, 16 (4.3%) of them also had changes in the recommended wide local excision radial margin.

CONCLUSIONS

IPR of invasive melanoma leads to both changes in staging and the surgical management of melanoma and should remain an important component of care of melanoma patients at a tertiary referral center.

A second expert pathology review of cutaneous melanoma in multidisciplinary meetings: Impact on treatment decisions

Melanoma causes substantial burden of medical costs and years of life lost. Wide variations in melanoma diagnosis and treatment have been identified at least in the United States, Australia, Germany, Italy and France [1]. The variation especially in the quality of reporting on pathological specimens has been reported. The aim of this retrospective study was to assess the impact of expert pathology review of melanoma on the staging and thus treatment decisions in cutaneous melanoma patients in a multidisciplinary tumor board. A total of 567 patients were referred to the multidisciplinary meeting with a diagnosis of new invasive or in situ melanoma from 14.10.2014 to 31.5.2018. Among these patients, a second expert histopathologic review resulted in changes in interpretation for 46 out of 567 (8%) patients. Of patients originally diagnosed with melanoma, pathologic review led to a change in diagnosis to benign lesions in 19 cases. The Breslow thickness changed >0.3 mm in 22 cases leading changes in staging and thus treatment. Minor changes (≤0.3 mm) in Breslow thickness was found in 5 cases. Our data suggest that review of melanoma by an expert dermatopathologist results in frequent, clinically meaningful alterations in diagnosis, staging and surgical treatment. The confirmation of a cancer diagnosis should be the first step in the initiation of multidisciplinary monitoring especially in patients younger than 40 years old and early-stage tumors.

Vertical Growth Phase as a Prognostic Factor for Sentinel Lymph Node Positivity in Thin Melanomas: A Systematic Review and Meta-Analysis

BACKGROUND

The 2010 American Joint Committee on Cancer guidelines recommended consideration of sentinel lymph node biopsy for thin melanoma (Breslow thickness <1.0 mm) with aggressive pathologic features such as ulceration and/or high mitotic rate. The therapeutic benefit of biopsy-based treatment remains controversial. The authors conducted a meta-analysis to estimate the risk and outcomes of sentinel lymph node positivity in thin melanoma, and examined established and potential novel predictors of positivity.

METHODS

Three databases were searched by two independent reviewers for sentinel lymph node positivity in patients with thin melanoma. Study heterogeneity, publication bias, and quality were assessed. Data collected included age, sex, Breslow thickness, mitotic rate, ulceration, regression, Clark level, tumor-infiltrating lymphocytes, and vertical growth phase. Positivity was estimated using a random effects model. Association of positivity and clinicopathologic features was investigated using meta-regression.

RESULTS

Ninety-three studies were identified representing 35,276 patients with thin melanoma who underwent sentinel lymph node biopsy. Of these patients, 952 had a positive sentinel lymph node biopsy, for an event rate of 5.1 percent (95 percent CI, 4.1 to 6.3 percent). Significant associations were identified between positivity and Breslow thickness greater than 0.75 mm but less than 1.0 mm, mitotic rate, ulceration, and Clark level greater than IV. Seven studies reported on vertical growth phase, which was strongly associated with positivity (OR, 4.3; 95 percent CI, 2.5 to 7.7).

CONCLUSIONS

To date, this is the largest meta-analysis to examine predictors of sentinel lymph node biopsy positivity in patients with thin melanoma. Vertical growth phase had a strong association with biopsy positivity, providing support for its inclusion in standardized pathologic reporting.

Inter-observer variation in the histopathology reports of head and neck melanoma; a comparison between the seventh and eighth edition of the AJCC staging system

BACKGROUND

TNM staging of melanoma has recently been altered by the introduction of the 8th edition of the AJCC Cancer Staging manual. The purpose of this study is to analyze the inter-observer variation of histopathology reports and its effect on recommended treatment policy.

METHODS

We retrospectively analyzed 296 cases, diagnosed as primary cutaneous head and neck melanoma (2005-2016), referred to the Netherlands Cancer Institute (NCI) for treatment after prior diagnosis in another hospital (non-NCI). All reports were analyzed for patients demographics, tumor characteristics and histopathologic features.

RESULTS

In 53% and 40% of the cases, the histopathologic parameters were discordant, according to AJCC 7th and 8th edition, respectively. This indicated a perfect inter-observer agreement for the measurement of Breslow thickness (Intraclass correlation coefficient (ICC) = 0.981) and a substantial agreement for subtype (kappa statistic (κ) = 0.648) and ulceration (κ = 0.802), while only moderate for dermal mitotic activity (κ = 0.472). After NCI review, recommended treatment policies were changed in 13% and 11% of the patients when applying TNM 7 and TNM 8, respectively. Scheduling sentinel lymph node biopsy (SLNB) changed in 14 (5%) and 10 (3%) cases when using TNM 7 and TNM 8, respectively.

CONCLUSION

Review by a NCI pathologist of histopathologic parameters of primary cutaneous head and neck melanoma led to significant changes in treatment decision. Introduction of the AJCC 8th edition led to slightly less discordances between NCI and non-NCI reports and consequently smaller impact on treatment planning. Expert review remains indicated when a SLNB is considered for additional staging in selected cases.

Histologic review of melanomas by pathologists trained in melanocytic lesions may change therapeutic approach in up to 41.9% of cases

Melanoma Guidelines of the Brazilian Dermatology Society recommend histologic review by pathologists trained in melanocytic lesions whenever possible. Out of 145 melanoma cases identified at a private clinic in São Paulo/Brazil, 31 that had been submited to histologic review were studied to evaluate whether revision had led to change in therapeutic approach.. Differences in original/reviewed reports were found in 58.1% (n=18) of the reports, leading to changes in therapeutic approach in 41.9% (n=13). Change in diagnosis was observed in 6 out of 31 (19,3%) cases. These findings suggest that second opinion by pathologists trained in melanocytic lesions is likely to show significant differences from the original report.

Identification of patients at risk of metastasis using a prognostic 31-gene expression profile in subpopulations of melanoma patients with favorable outcomes by standard criteria

BACKGROUND

A substantial number of patients who relapse and die from cutaneous melanoma (CM) are categorized as being at low risk by traditional staging factors. The 31-gene expression profile (31-GEP) test independently stratifies metastatic risk of patients with CM as low (Class 1, with 1A indicating lowest risk) or high (Class 2,with 2B indicating highest risk).

OBJECTIVE

To assess risk prediction by the 31-GEP test within 3 low-risk (according to the American Joint Committee on Cancer) populations of patients with CM: those who are sentinel lymph node (SLN) negative, those with stage I to IIA tumors, and those with thin (≤1 mm [T1]) tumors.

METHODS

A total of 3 previous validation studies provided a nonoverlapping cohort of 690 patients with 31-GEP results, staging information, and survival outcomes. Kaplan-Meier and Cox regression analysis were performed.

RESULTS

The results included the identification of 70% of SLN-negative patients who experienced metastasis as Class 2, the discovery of reduced recurrence-free survival for patients with thin tumors and Class 2B biology compared with that of those with Class 1A biology (P < .0001); and determination of the 31-GEP test as an independent predictor of risk compared with traditional staging factors in patients with stage I to IIA tumors.

LIMITATIONS

Diagnoses spanned multiple versions of pathologic staging criteria.

CONCLUSIONS

The 31-GEP test identifies high-risk patients who are likely to experience recurrence or die of melanoma within low-risk groups of subpopulations of patients with CM who have SLN-negative disease, stage I to IIA tumors, and thin tumors.

MART-1-labeled melanocyte density and distribution in actinic keratosis and squamous cell cancer in situ: Pagetoid melanocytes are a potential source of misdiagnosis as melanoma in situ

BACKGROUND

Actinic keratosis (AK) and squamous cell carcinoma in-situ (SCCIS) within or near melanoma in situ (MIS) can complicate diagnosis due to overlapping clinical and microscopic features. This study aimed to describe basilar melanocyte density and pagetoid spread in AK and SCCIS for improved diagnostic accuracy.

METHODS

A total of 22 AK and 22 SCCIS biopsies containing a margin of uninvolved epidermis were immunostained with MART-1 (melanoma antigen recognized by T-cells 1). The basilar melanocyte:keratinocyte ratio and the number and distribution of pagetoid melanocytes were compared in AK, SCCIS, and uninvolved epidermis. An in-vitro human skin model was created to assess the impact of keratinocyte atypia on melanocyte distribution.

RESULTS

The median basilar melanocyte:keratinocyte ratio in SCCIS (1:11.49) was lower than in uninvolved epidermis (1:5.59, P = 0.0011), and the ratio in AK (1:6.94) was similar to uninvolved epidermis (P = 0.987). Pagetoid melanocytes were absent in perilesional skin but common in AK (21/22, P < 0.0001) and SCCIS (22/22, P < 0.0001). Pagetoid melanocytes at or above the mid-spinous layer were more common in SCCIS (21/22) vs AK (7/22, P < 0.0001). Pagetoid melanocytes were present in the in-vitro skin model made with neoplastic but not normal keratinocytes.

CONCLUSIONS

Pagetoid melanocytes in AK and SCCIS should be interpreted with caution to avoid overdiagnosis of MIS.

Improving classification of melanocytic nevi: Association of BRAF V600E expression with distinct histomorphologic features

BACKGROUND

A subset of melanomas carrying a B-Raf proto-oncogene, serine/threonine kinase gene (BRAF) V600E mutation, which is the most common targetable mutation in melanoma, arise in association with a melanocytic nevus that is also harboring a BRAF V600E mutation. The detailed histomorphologic characteristics of nevi positive for BRAF V600E have not been systematically documented.

OBJECTIVE

To identify histomorphologic features correlating with BRAF V600E status in nevi.

METHODS

We retrospectively identified melanocytic nevi from our laboratory reporting system. We performed a histomorphologic analysis and analysis of BRAF V600E expression by immunohistochemistry.

RESULTS

Thirteen nevi (14.8%) were negative and 76 (86.4%) were positive for BRAF V600E. The nevi positive for BRAF V600E were predominantly dermal (predominantly dermal growth in 55.3% of nevi positive for BRAF V600E and 15.4% of nevi negative for BRAF V600E [P = .01]) and showed a congenital growth pattern (congenital growth pattern in 51.3% of nevi positive for BRAF V600E and 15.4% of nevi negative for BRAF V600E [P = .02]). Compared with nevi negative for BRAF V600E, those that were positive for BRAF V600E often exhibited predominantly nested intraepidermal melanocytes, larger junctional nests, abrupt lateral circumscription, and larger cell size. Architectural disorder and inflammatory infiltrates were seen more often in nevi negative for BRAF V600E. BRAF sequencing of a subset of nevi confirmed the immunohistochemical results.

LIMITATIONS

Limitations include the study's retrospective design and the small sample size of nevi negative for BRAF V600E.

CONCLUSIONS

BRAF V600E is associated with distinct histomorphologic features in nevi. These features may contribute to improving the accuracy of classification and diagnosis of melanocytic neoplasms.

Clinicopathological characteristics of cutaneous malignant melanoma in patients at a tertiary hospital in Macaronesia. Survival as a function of locoregional prognostic factors per the American Joint Committee on Cancer

BACKGROUND

Despite suffering high ultraviolet radiation levels, few data on malignant melanoma (MM) in Macaronesia are available.

METHODS

Observational study of cutaneous MM cases diagnosed during a period of 12 years at a tertiary hospital in Canary Islands.

RESULTS

A total of 532 patients (female/male = 1.4) with an average age of 56 years were included; 5% developed more than one MM, and 7% reported family history of MM. Phototype II (43%), dark eyes (41%), and dark hair (41%) predominated. There was a lower frequency of light-colored hair and eyes in those born in the Canary Islands. The most frequent locations of MM were on the back for men (37%) and on the lower extremities for women (35%). Among the infiltrating tumors (83%), the (median) thickness was 1.07 mm (women, 0.90 mm; men, 1.21 mm). Anatomopathological ulceration (AU) and a mitotic rate ≥1 mitosis/mm² (HMR) were recorded in 27% of patients. Patients with regional disease constituted 12% of the population. The most common stage was IA (34%). Melanoma-specific survival (MSSV) decreased significantly with thickness, presence of AU, HMR, and sentinel lymph node disease. These four variables were independent prognostic factors. The five-year MSSV varied between 100% (stage IA) and 39% (stage IIIC).

CONCLUSIONS

The characteristics of the patients were similar to those published in datasets from continental Europe, although the pigmentary features were darker in those originating from Macaronesia. The prognostic parameters described in the 7th edition of the American Joint Committee on Cancer (AJCC) independently predict MSSV in our patients.

Diagnostic utility of epithelial and melanocitic markers with double sequential immunohistochemical staining in differentiating melanoma in situ from invasive melanoma

Identification of melanoma in situ and its distinction from invasive melanoma is important because of its significant impact on morbidity and mortality. However, this interpretation can cause pitfalls in the diagnosis even with the use of immunohistochemistry. The aim of this study is to evaluate the diagnostic utility of epithelial makers (AE1/AE3, CK5/6, and p63) combined with melanocytic markers (HMB-45, S-100, or Melan-A) using dual-color immunohistochemical staining, performed on a single slide by sequentially applying the antibodies. In this study, we show 4 cases in which examination of routine hematoxylin and eosin slides did not allow for clear-cut distinction between in situ and invasive melanoma and highlight the utility of the double-staining method. Therefore, we recommend this double-staining method with melanocytic and epithelial markers as a helpful adjunct to the diagnosis of cases with a differential diagnosis between in situ and invasive melanoma.

Guidelines of the Brazilian Dermatology Society for diagnosis, treatment and follow up of primary cutaneous melanoma--Part I

The last Brazilian guidelines on melanoma were published in 2002. Development in diagnosis and treatment made updating necessary. The coordinators elaborated ten clinical questions, based on PICO system. A Medline search, according to specific MeSH terms for each of the 10 questions was performed and articles selected were classified from A to D according to level of scientific evidence. Based on the results, recommendations were defined and classified according to scientific strength. The present Guidelines were divided in two parts for editorial and publication reasons. In the first part, the following clinical questions were answered: 1) The use of dermoscopy for diagnosis of primary cutaneous melanoma brings benefits for patients when compared with clinical examination? 2) Does dermoscopy favor diagnosis of nail apparatus melanoma? 3) Is there a prognostic difference when incisional or excisional biopsies are used? 4) Does revision by a pathologist trained in melanoma contribute to diagnosis and treatment of primary cutaneous melanoma? What margins should be used to treat lentigo maligna melanoma and melanoma in situ?

Interpretive Diagnostic Error Reduction in Surgical Pathology and Cytology: Guideline From the College of American Pathologists Pathology and Laboratory Quality Center and the Association of Directors of Anatomic and Surgical Pathology

CONTEXT

Additional reviews of diagnostic surgical and cytology cases have been shown to detect diagnostic discrepancies.

OBJECTIVE

To develop, through a systematic review of the literature, recommendations for the review of pathology cases to detect or prevent interpretive diagnostic errors.

DESIGN

The College of American Pathologists Pathology and Laboratory Quality Center in association with the Association of Directors of Anatomic and Surgical Pathology convened an expert panel to develop an evidence-based guideline to help define the role of case reviews in surgical pathology and cytology. A literature search was conducted to gather data on the review of cases in surgical pathology and cytology.

RESULTS

The panel drafted 5 recommendations, with strong agreement from open comment period participants ranging from 87% to 93%. The recommendations are: (1) anatomic pathologists should develop procedures for the review of selected pathology cases to detect disagreements and potential interpretive errors; (2) anatomic pathologists should perform case reviews in a timely manner to avoid having a negative impact on patient care; (3) anatomic pathologists should have documented case review procedures that are relevant to their practice setting; (4) anatomic pathologists should continuously monitor and document the results of case reviews; and (5) if pathology case reviews show poor agreement within a defined case type, anatomic pathologists should take steps to improve agreement.

CONCLUSIONS

Evidence exists that case reviews detect errors; therefore, the expert panel recommends that anatomic pathologists develop procedures for the review of pathology cases to detect disagreements and potential interpretive errors, in order to improve the quality of patient care.

Impact of the 2009 AJCC staging guidelines for melanoma on the number of mitotic figures reported by dermatopathologists at one institution

BACKGROUND

In 2009 the revised seventh staging system for melanoma recommended the use of mitotic count to separate stage T1a from T1b. However, careful scrutiny of cases may lead to an inadvertent selection effect, with consequent increased reporting of mitotic counts.

METHODS

We investigated whether there is a significant increase in mitotic counts reported since 2009 for melanomas with a Breslow thickness of 1.0 mm or less. We conducted a retrospective, case-controlled study examining invasive melanoma cases at a large academic center. Mitotic counts were compared between pathology reports before 2009 (n = 61) and after 2009 (n = 125), with a subset of slides re-examined in a blinded fashion.

RESULTS

Before the 2009 staging guidelines, 51% of cases had one or more mitosis reported compared to 38% after 2009 (p = 0.113). Blinded re-counting did not yield a significant difference when compared with the original pathology reports in either group.

CONCLUSIONS

There was not a significant difference in the number of mitoses reported after the implementation of the new guidelines.

Early-stage non-Spitzoid cutaneous melanoma in patients younger than 22 years of age at diagnosis: long-term follow-up and survival analysis

PURPOSE

We evaluated prognostic factors among young patients with early stage melanoma, with particular attention to survival, recurrence, and development of a second primary melanoma.

METHODS

We retrospectively reviewed patients (age <22 years) with pathologically confirmed in-situ and stage 1 non-Spitzoid melanoma treated at our institution from 1980-2010, assessing demographics, clinical presentation, treatment, disease-specific survival, recurrence-free survival, and probability of developing a second primary melanoma.

RESULTS

One hundred patients with in-situ melanoma (n=16) or stage 1A (n=48) or 1B (n=36) melanoma were identified. Median age was 19.4 years (range, 11.2-21.9), and median follow-up was 7.6 years (range, 0.1-31.7). Median tumor thickness was 0.76 mm (range, 0.23-2.0). No lesions were ulcerated. All patients underwent wide local excision with negative margins, and 21 had a concomitant negative sentinel lymph node biopsy (SLNB). Sixteen patients developed recurrences, and 8 subsequently died of progressive melanoma. There were 2 non-melanoma-related deaths. Endpoints were 20-year overall survival (77.4%), melanoma-specific mortality (20.1%), recurrence rate (34.0%), and probability of developing a second primary melanoma (24.7%). Greater tumor depth and Clark level were associated with worse prognosis, but age, sex, and tumor mitotic rate were not correlated with recurrence or survival.

CONCLUSION

Among younger early-stage melanoma patients, greater lesion depth conferred higher recurrence risk and mortality. Our data did not define the role of sentinel lymph node biopsy in this group.

Budget impact analysis of a novel gene expression assay for the diagnosis of malignant melanoma

BACKGROUND

Traditional pathology techniques alone can be insufficient to reliably distinguish between malignant melanoma, dysplastic nevi, and benign nevi in biopsies of suspicious pigmented lesions. Numerous studies have shown high rates of ambiguity when assessing such samples. A novel gene expression assay has been developed to objectively differentiate malignant melanoma from benign nevi.

OBJECTIVE

The purpose of this study was to quantify the economic impact of the gene expression assay on a US commercial health plan.

METHODS

The clinical paradigm of care was modeled for a hypothetical cohort of patients with suspicious pigmented lesions that are difficult-to-diagnose. Costs were assigned to each unit of care provided based on 2013 Medicare fee-for-service rates. Patients were followed for 10 years and were modeled to progress according to the natural history of their disease. The total cost of care was calculated for two scenarios: a Reference Scenario, representing current clinical practice, and a Test Scenario, in which each lesion was tested with the gene expression assay and diagnosed. Total cost of care was compared between the two scenarios to determine overall budget impact. Sensitivity analyses were performed to test the robustness of the model.

RESULTS

The gene expression assay reduces costs by $1268 per patient tested over 10 years, a decrease of 8.3%, after accounting for the cost of the assay. For a health plan with 10 million members, this would translate to over $8 million in savings. The largest portion of this saving comes from reducing the number of missed melanomas, which would otherwise progress to advanced disease. In sensitivity analyses, no single model input changed within a reasonable range of values caused the model to show that the assay was not cost-saving.

CONCLUSION

In addition to improving the diagnosis of melanoma, this gene expression assay would likely reduce costs for health plans that choose to cover it.

Is it worth reorganising cancer services on the basis of multidisciplinary teams (MDTs)? A systematic review of the objectives and organisation of MDTs and their impact on patient outcomes

Multidisciplinary teams (MDTs) are considered the gold standard of cancer care in many healthcare systems, but a clear definition of their format, scope of practice and operational criteria is still lacking. The aims of this review were to assess the impact of MDTs on patient outcomes in cancer care and identify their objectives, organisation and ability to engage patients in their care. We conducted a systematic review of the literature in the Medline database. Fifty-one peer-reviewed papers were selected from November 2005 to June 2012. MDTs resulted in better clinical and process outcomes for cancer patients, with evidence of improved survival among colorectal, head and neck, breast, oesophageal and lung cancer patients in the study period. Also, it was observed that MDTs have been associated with changes in clinical diagnostic and treatment decision-making with respect to urological, pancreatic, gastro-oesophageal, breast, melanoma, bladder, colorectal, prostate, head and neck and gynaecological cancer. Evidence is consistent in showing positive consequences for patients' management in multiple dimensions, which should encourage the development of structured multidisciplinary care, minimum standards and exchange of best practices.

Principles of surgical treatment of malignant melanoma

Although melanoma represents less than 5% of all skin cancers, it is responsible for the bulk of skin cancer-related deaths. Nevertheless, despite this aggressive reputation, most patients with cutaneous melanoma will be surgically cured of their disease. Early detection allows for curative resection, and 5-year survival for all stages of melanoma is 91%. This review outlines the surgical treatment of melanoma, including principles of wide local excision and management of the regional lymph nodes.

Accuracy of diagnostic biopsy for cutaneous melanoma: implications for surgical oncologists

BACKGROUND AND OBJECTIVES

While excisional biopsy is recommended to diagnose cutaneous melanoma, various biopsy techniques are used in practice. We undertook this study to identify how frequently final tumor stage and treatment recommendations changed from diagnostic biopsy to final histopathology after wide local excision (WLE).

METHODS

We compared the histopathology of the dermatopathologist-reviewed diagnostic biopsy and final WLE in 332 cutaneous melanoma patients.

RESULTS

Tumor sites were extremity (51%), trunk (33%), and head/neck (16%). Initial biopsy types were excisional (56%), punch (21%), shave (18%), and incisional (5%). Most diagnostic biopsies were margin positive regardless of technique, and 36% of patients had residual melanoma on WLE. T-stage changed in 8% of patients, of whom 59% were diagnosed by punch biopsy, 15% by incisional biopsy, 15% by shave biopsy, and 11% by excisional biopsy (P < 0.0001). Treatment recommendations changed in 6%: 2% after excisional biopsy, 5% after shave biopsy, 18% after punch biopsy, and 18% after incisional biopsy (P < 0.0001).

CONCLUSIONS

Although most biopsy margins were positive, T-stage and treatment changed for only a minority of melanoma patients. Our data provide valuable information to inform patient discussion regarding the likelihood of a change in prognosis and the need for secondary procedures after WLE. These data support the superiority of dermatopathologist-reviewed excisional biopsy when feasible.

Impact of a single-day multidisciplinary clinic on the management of patients with liver tumours

PURPOSE

Multidisciplinary cancer clinics may improve patient care. We examined how a single-day multidisciplinary liver clinic (mdlc) affected care recommendations for patients compared with the recommendations provided before presentation to the mdlc.

METHODS

We analyzed the demographic and clinicopathologic data of 343 patients assessed in the Johns Hopkins Liver Tumor Center from 2009 to 2012, comparing imaging and pathology interpretation, diagnosis, and management plan between the outside provider (osp) and the mdlc.

RESULTS

Most patients were white (n = 259, 76%); median age was 60 years; and 146 were women (43%). Outside providers referred 182 patients (53%); the rest were self-referred. Patients travelled median of 83.4 miles (interquartile range: 42.7-247 miles). Most had already undergone imaging (n = 338, 99%) and biopsy (n = 194, 57%) at the osp, and a formal management plan had been formulated for about half (n = 168, 49%). Alterations in the interpretation of imaging occurred for 49 patients (18%) and of biopsy for 14 patients (10%). Referral to the mdlc resulted in a change of diagnosis in 26 patients (8%), of management plan in 70 patients (42%), and of tumour resectability in 7 patients (5%). Roughly half the patients (n = 174, 51%) returned for a follow-up, and 154 of the returnees (89%) received treatment, primarily intraarterial therapy (n = 88, 57%), systemic chemotherapy (n = 60, 39%), or liver resection (n = 32, 21%). Enrollment in a clinical trial was proposed to 34 patients (10%), and 21 of the 34 (62%) were accrued.

CONCLUSIONS

Patient assessment by our multidisciplinary liver clinic had a significant impact on management, resulting in alterations to imaging and pathology interpretation, diagnosis, and management plan. The mdlc is an effective and convenient means of delivering expert opinion about the diagnosis and management of liver tumours.

Assessment of copy number status of chromosomes 6 and 11 by FISH provides independent prognostic information in primary melanoma

Melanoma incidence has been rising steadily for decades, whereas mortality rates have remained flat. This type of discordant pattern between incidence and mortality has been linked to diagnostic drift in cancers of the thyroid, breast, and prostate. Ancillary tests, such as fluorescent in situ hybridization (FISH), are now being used to help differentiate melanomas from melanocytic nevi. Multicolor FISH has been shown to distinguish between these 2 with 86.7% sensitivity and 95.4% specificity. To assess the ability of FISH to differentiate melanomas with metastatic or lethal potential from those with an indolent disease course, we performed FISH with probes targeting 6p25, centromere 6, 6q23, and 11q13 on 144 primary melanomas with a minimal tumor thickness of 2 mm and compared the development of metastatic disease and melanoma-specific mortality as well as relapse-free and disease-specific survival between FISH-positive and FISH-negative cases. Of the melanomas, 82% were positive by FISH according to previously defined criteria. The percentage was significantly higher (93%) in cases that developed systemic metastases (n=43) than in patients that did not (77%, n=101). FISH-positive primaries had a significantly increased risk of metastasis or melanoma-related death compared with FISH-negative cases odds ratio 4.11; confidence interval, 1.14-22.7 and odds ratio 7.0, confidence interval 1.03-300.4, respectively. FISH status remained an independent parameter when controlling for known prognostic factors. These data indicate that the group of melanomas diagnosed with routine histopathology that lack aberrations detected by FISH is enriched for melanomas with a more indolent disease course. This suggests that molecular techniques can assist in a more accurate identification of tumors with metastatic potential.

Shave biopsy is a safe and accurate method for the initial evaluation of melanoma

BACKGROUND

Shave biopsy of cutaneous lesions is simple, efficient, and commonly used clinically. However, this technique has been criticized for its potential to hamper accurate diagnosis and microstaging of melanoma, thereby complicating treatment decision-making.

STUDY DESIGN

We retrospectively analyzed a consecutive series of patients referred to the University of Florida Shands Cancer Center or to the Moffitt Cancer Center for treatment of primary cutaneous melanoma, initially diagnosed on shave biopsy to have Breslow depth < 2 mm, to determine the accuracy of shave biopsy in T-staging and the potential impact on definitive surgical treatment and outcomes.

RESULTS

Six hundred patients undergoing shave biopsy were diagnosed with melanoma from extremity (42%), trunk (37%), and head or neck (21%). Mean (± SEM) Breslow thickness was 0.73 ± 0.02 mm; 6.2% of lesions were ulcerated. At the time of wide excision, residual melanoma was found in 133 (22%), resulting in T-stage upstaging for 18 patients (3%). Recommendations for additional wide excision or sentinel lymph node biopsy changed in 12 of 600 (2%) and 8 of 600 patients (1.3%), respectively. Locoregional recurrence occurred in 10 (1.7%) patients and distant recurrence in 4 (0.7%) patients.

CONCLUSIONS

These data challenge the surgical dogma that full-thickness excisional biopsy of suspicious cutaneous lesions is the only method that can lead to accurate diagnosis. Data obtained on shave biopsy of melanoma are reliable and accurate in the overwhelming majority of cases (97%). The use of shave biopsy does not complicate or compromise management of the overwhelming majority of patients with malignant melanoma.

Prognostic significance of mitotic rate in localized primary cutaneous melanoma: an analysis of patients in the multi-institutional American Joint Committee on Cancer melanoma staging database

PURPOSE

The aim of this study was to assess the independent prognostic value of primary tumor mitotic rate compared with other clinical and pathologic features of stages I and II melanoma.

METHODS

From the American Joint Committee on Cancer (AJCC) melanoma staging database, information was extracted for 13,296 patients with stages I and II disease who had mitotic rate data available.

RESULTS

Survival times declined as mitotic rate increased. Ten-year survival ranged from 93% for patients whose tumors had 0 mitosis/mm(2) to 48% for those with ≥ 20/mm(2) (P < .001). Mean number of mitoses/mm(2) increased as the primary melanomas became thicker (1.0 for melanomas ≤ 1 mm, 3.5 for 1.01 to 2.0 mm, 7.3 for 3.01 to 4.0 mm, and 9.6 for > 8 mm). Ulceration was also associated with a higher mitotic rate; 59% of ulcerated melanomas had ≥ 5 mitoses/mm(2) compared with 16% of nonulcerated melanomas (P < .001). In a multivariate analysis of 10,233 patients, the independent predictive factors for survival in order of statistical significance were as follows: tumor thickness (χ(2) = 104.9; P < .001), mitotic rate (χ(2) = 67.0; P < .001), patient age (χ(2) = 48.2; P < .001), ulceration (χ(2) = 46.4; P < .001), anatomic site (χ(2) = 34.6; P < .001), and patient sex (χ(2) = 33.9; P < .001). Clark level of invasion was not an independent predictor of survival (χ(2) = 3.2; P = .37).

CONCLUSION

A high mitotic rate in a primary melanoma is associated with a lower survival probability. Among the independent predictors of melanoma-specific survival, mitotic rate was the strongest prognostic factor after tumor thickness.

Does mitotic rate predict sentinel lymph node metastasis or survival in patients with intermediate and thick melanoma?

BACKGROUND

The significance of mitotic rate (MR) in melanoma remains controversial.

METHODS

In this retrospective analysis of a prospective randomized trial that included patients with melanoma of 1.0 mm or greater, all patients underwent wide excision and sentinel node (sentinel lymph node [SLN]) biopsy. Univariate and multivariate analyses were performed to evaluate factors predictive of disease-free survival (DFS) and overall survival (OS).

RESULTS

A total of 551 patients had MR reported. A cut-off point of 6 mitoses/mm(2) best discriminated DFS and OS: 455 patients (82.6%) had MR less than 6/mm(2). SLN were tumor-positive in 14.7% of low MR versus 31.3% of high MR patients (P = .0003). There were significant differences in DFS (P = .0014) and OS (P = .0002) between the 2 groups, however, MR failed to remain significant in the multivariate model.

CONCLUSIONS

MR is weakly predictive of SLN status but it is not an independent predictor of survival for melanomas 1.0 mm or thicker.