TERT amplification but not activation of canonical Wnt/β-catenin pathway is involved in acral lentiginous melanoma progression to metastasis

PRAME and LEF1 in Combined Deep Penetrating Nevus and Combined Blue Nevus: Utility and Pitfalls

ABSTRACT

Deep penetrating nevi (DPN), particularly those showing combined features, or combined deep penetrating nevi (CDPN), may show histopathological resemblance to blue nevus (BN) and melanoma. Preferentially Expressed Antigen in MElanoma (PRAME) is a marker that helps distinguish melanoma from benign melanocytic lesions. Lymphoid enhancer-binding factor 1 (LEF1) has been proposed to be used in conjunction with β-catenin for diagnosis of DPN. The immunohistochemical expression of PRAME and LEF1 was evaluated in 10 DPN (including 6 CDPN and 2 DPN-like proliferations with atypical features), 16 BN (including combined and cellular BN), and 2 melanomas with features of DPN or BN. PRAME was negative in most DPN (n = 10/10, n = 9/10, one case with discrepancy between readers) and all BN (n = 16/16), while the 2 melanomas included were positive (n = 2/2). All DPN were positive for LEF1 (n = 9/9) while only a subset of BN were positive (n = 6/16, P = 0.0028; n = 5/16, P = 0.001, per both readers). LEF1 seemed to be easier to interpret than β-catenin because of its nuclear pattern of expression. The expression of LEF1 in the regular nevus component of combined BN presents a potential pitfall in practice because it may lead to misinterpretation of LEF1 as positive in the BN component of the lesion. However, a subset (approximately one-third) of combined BN seemed to show true LEF1 expression. Taking into account pitfalls in interpretation, the combinatorial panel of PRAME and LEF1, in addition to conventional histopathological features, may be useful to distinguish CDPN from combined BN and other benign and malignant mimics.

Extensive review on breast cancer its etiology, progression, prognostic markers, and treatment

As the most frequent and vulnerable malignancy among women, breast cancer universally manifests a formidable healthcare challenge. From a biological and molecular perspective, it is a heterogenous disease and is stratified based on the etiological factors driving breast carcinogenesis. Notably, genetic predispositions and epigenetic impacts often constitute the heterogeneity of this disease. Typically, breast cancer is classified intrinsically into histological subtypes in clinical landscapes. These stratifications empower physicians to tailor precise treatments among the spectrum of breast cancer therapeutics. In this pursuit, numerous prognostic algorithms are extensively characterized, drastically changing how breast cancer is portrayed. Therefore, it is a basic requisite to comprehend the multidisciplinary rationales of breast cancer to assist the evolution of novel therapeutic strategies. This review aims at highlighting the molecular and genetic grounds of cancer additionally with therapeutic and phytotherapeutic context. Substantially, it also renders researchers with an insight into the breast cancer cell lines as a model paradigm for breast cancer research interventions.

Molecular characterization of biphenotypic epithelioid and plexiform melanoma with deep penetrating nevus-like features

Tumor heterogeneity is a relevant hallmark of melanoma due to the high mutation burden and immunogenicity commonly encountered. Heterogeneity at the histologic level frequently corresponds to heterogeneity at the molecular level. A better understanding of this feature of malignancy can help refine the development of predictive biomarkers and to define more effective targeted therapies. Here, we describe a case of melanoma displaying a dual phenotype: a DPN-like/plexiform portion in conjunction with a conventional epithelioid morphology. Molecular studies revealed shared BRAF and PTEN mutations in both components but a CTNNB1 mutation was exclusively found in the DPN-like area of the tumor, consistent with the distinct morphology observed. There was considerable heterogeneity in sequence variants identified in the two regions. Gene expression analysis highlighted differentially regulated genes between the two histologies, including a relevant cluster of genes in the receptor tyrosine kinase (RTK) family and related signaling pathways upregulated in the DPN-like/plexiform area.

Genetic characteristics and response to systemic therapies of acral lentiginous melanoma at a tertiary care center-a retrospective review

BACKGROUND

Acral lentiginous melanoma (ALM) is an aggressive subtype of cutaneous malignant melanomas that accounts for 50-80% of melanomas in ethnic minorities. Studies on the genetic profile of these tumors largely result from cohorts in Europe, Asia, and Latin America, few inclusive of Black patients.

OBJECTIVE

We aim to describe the clinicopathological and genetic characteristics in a diverse cohort of ALM patients.

METHODS

A retrospective analysis of 93 patients with a pathology confirmed diagnosis of ALM between March 1984 and October 2020 was conducted at a large tertiary care center. Melanoma mutation panel testing for frequently mutated regions of the BRAF, NRAS, KIT and PIK3CA genes were reviewed in patient records when available.

RESULTS

Of the 93 patients identified, 62.4% were Caucasian, 25.8% Black, 4.30% Hispanic, 4.30% Asian, and 3.22% identified as other. Fourteen of 17 patients receiving targeted or immunologic agents experienced disease progression during treatment, including all patients with a BRAF V600E mutation.

LIMITATIONS

This was a single-center retrospective analysis.

CONCLUSION

Response to targeted and immunologic therapies in ALM patients was overwhelming poor, particularly in BRAF V600E-mutated tumors in contrast to the positive prognosis associated with BRAF V600E mutations in other advanced cutaneous melanoma subtypes.

Prognostic significance of acral lentiginous histologic type in T1 melanoma

Acral lentiginous melanoma (ALM) is a rare type of cutaneous melanoma with a poor prognosis. It is unclear whether the poor outcome of ALM is due to its inherent disease characteristics or advanced stage at initial diagnosis. To address this question, we retrospectively analyzed the clinicopathologic factors of 828 thin (T1; Breslow thickness ≤1.0 mm) melanomas [129 (15.6%) ALMs and 699 (84.4%) non-ALMs] and their nodal and distance metastases and local recurrence rates and determined their relationship with the disease-specific (DSS), overall (OS), and recurrence-free survivals (RFS) at the pathologic stages T1, T1a, and T1b with a median follow-up time of 84.5 months. With the exception of OS at T1b stage, ALM patients showed significantly lower 5- and 10-year DSS, OS, and RFS rates at every pathologic stage when compared with non-ALM. In multivariable analysis, ALM histologic type, SLN positivity, age, and the use of systemic therapy were detected as independent poor prognostic factors associated with significantly lower survival rates. ALM histologic type was associated with lower DSS and OS rates at T1 and T1a stages and lower RFS rates at T1b stage. SLN positivity was associated with lower DSS, OS, and RFS rates at T1, T1a, and T1b stages. Age was associated with lower OS rates at T1 and T1b stages. Whereas the use of systemic therapy was associated with lower DSS rates at T1a stage and RFS rates at T1b stage. In addition, the ALM group showed significantly older median age patients and higher rates of female sex, Hispanic ethnicity, nevoid cytology, non-brisk tumor-infiltrating lymphocytes, nodal metastasis, and local recurrence at every pathologic stage of thin melanoma. Our findings suggest that ALM is inherently more aggressive than other types of cutaneous melanoma. This information may be useful for prognostic stratification of patients with thin melanomas, especially to help guide the clinical decision-making for SLN biopsy and patients entering clinical trials.

Pathology-based Biomarkers Useful for Clinical Decisions in Melanoma

The dramatic recent advances in therapy of melanoma require a more personalized and precise diagnostic approach to aid in clinical decisions. Tissue-based biomarkers in pathology have diagnostic, prognostic and predictive relevance. Herein we review the most commonly used pathology-based biomarkers in melanoma. Most of these biomarkers are evaluated through immunohistochemistry (IHC) or fluorescent in situ hybridization (FISH) performed on formalin fixed paraffin embedded tissue (FFPE), and are widely available in clinical pathology laboratories. We describe the utility of MART1/Ki67, p16, PRAME, markers of lymphovascular invasion (D2-40, CD31, D2-40/MITF, CD31/SOX-10), BRAF V600E, NRAS, KIT, BAP1, ALK, NTRK, PD-L1, TERT, PTEN, iNOS, and MMR proteins (MLH1, MSH2, MSH6, PMS2) in the evaluation of melanoma specimens. Correct interpretation and awareness of the significance of these biomarkers is crucial for pathologists, dermatologists, and oncologists who take care of melanoma patients.