Essential Components of Melanoma Histopathological Reporting: The Surgical Oncologist's Perspective

The role of histological subtypes in the survival of patients diagnosed with cutaneous or mucosal melanoma in the United States of America

BACKGROUND

Literature presents limited information on histological subtypes and their association with other factors influencing the survival of melanoma patients. To explore the risk of death due to melanoma associated with histological subtypes, this retrospective study used the Surveillance, Epidemiology, and End Results program (SEER) data from 1998 to 2019.

METHODS

A total of 27,532 patients consisting of 15,527 males and 12,005 females. The Hypertabastic Accelerated Failure Time model was used to analyze the impact of histology on the survival of patients with cutaneous or mucosal melanoma.

RESULTS

The median survival time (MST) for cutaneous patients was 149 months, whereas those diagnosed with mucosal melanoma was 34 months. Nodular melanoma had a hazard ratio of 3.40 [95% CI: (2.94, 3.94)] compared to lentigo maligna melanoma. Across all histological subtypes, females had a longer MST, when compared to males. The hazard ratio (HR) of distant to localized melanoma was 9.56 [95% CI: (7.58, 12.07)].

CONCLUSIONS

Knowledge of patients' histological subtypes and their hazard assessment would enable clinicians and healthcare providers to perform personalized treatment, resulting in a lower risk of complication and higher survivability of melanoma patients. Significant factors were stage of the disease, age, histology, sex, and income. Focus should be placed on high-risk populations with severe and aggressive histological subtypes. Programs that emphasize preventive measures such as awareness, education, and early screening could reduce risk.

Reproducibility and Feasibility of Classification and National Guidelines for Histological Diagnosis of Canine Mammary Gland Tumours: A Multi-Institutional Ring Study

Histological diagnosis of Canine Mammary Tumours (CMTs) provides the basis for proper treatment and follow-up. Nowadays, its accuracy is poorly understood and variable interpretation of histological criteria leads to a lack of standardisation and impossibility to compare studies. This study aimed to quantify the reproducibility of histological diagnosis and grading in CMTs. A blinded ring test on 36 CMTs was performed by 15 veterinary pathologists with different levels of education, after discussion of critical points on the Davis-Thompson Foundation Classification and providing consensus guidelines. Kappa statistics were used to compare the interobserver variability. The overall concordance rate of diagnostic interpretations of WP on identification of hyperplasia-dysplasia/benign/malignant lesions showed a substantial agreement (average k ranging from 0.66 to 0.82, with a k-combined of 0.76). Instead, outcomes on ICD-O-3.2 morphological code /diagnosis of histotype had only a moderate agreement (average k ranging from 0.44 and 0.64, with a k-combined of 0.54). The results demonstrated that standardised classification and consensus guidelines can produce moderate to substantial agreement; however, further efforts are needed to increase this agreement in distinguishing benign versus malignant lesions and in histological grading.

Modern views on skin biopsy in the diagnostic algorithm of dermatooncological diseases

Background. Malignant neoplasms of the skin are fairly common tumors in the world population and among the population of Ukraine. The main method of diagnosing skintumors is a biopsy, which allows establishing a diagnosis at an early stage and ensures the cure of most patients. Purpose. To evaluate modern recommendations for skin biopsy in the diagnosis of dermato-onсological diseases. Materials and methods. The search for sources of information was conducted using the MEDLINE/PubMed, EMBASE/ExcerptaMedica, CochraneLibrary, PubMed та Google Scholar databases using the following keywords: skin biopsy, skin tumors, diagnosis, melanoma. Among the identified sources, works without statistical analysis, descriptions of individual cases, articles without conclusions, and sources with duplicate results were excluded. The search depth was 10 years. Results. As a result of the conducted search, 57 publications were found that corresponded to the declared purpose. The most common methods are: puncture, shaving, excisional and incisional biopsy. Most guidelines recommend full-thickness excisional biopsy as the preferred procedure for the diagnosis of suspected melanoma. It is indicated that a statistically significant mortality rate was found in the puncture biopsy group. Most observations showed no significant differences in melanoma recurrence between excisional biopsy and puncture groups. Given the clinical diversity of melanoma, there is no uniformity in the types of biopsies performed to diagnose melanoma. The most inaccurate method turned out to be the punch biopsy method, which is associated with an increased risk of underdiagnosis of melanoma. Conclusions. A skin biopsy is a mandatory first step to establish a definitive diagnosis of a skin tumor. Excisional complete biopsy is the most justified in most cases of diagnosis. Rational biopsy technique remains an issue that needs further study.

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.