Patterns of visceral metastasis in cutaneous melanoma: a descriptive study

Primary Melanoma Characteristics of Metastatic Disease: A Nationwide Cancer Registry Study

Simple Summary

Melanoma of the skin is the most lethal form of skin cancer. Almost 40% of the patients who die of metastatic melanoma did not have metastases at first diagnosis. More knowledge about patient and tumour characteristics as well as patterns of disease progression is needed. We described the characteristics and disease patterns of early-stage melanomas that progress into metastatic disease. We observed that more than half of the patients with metastases were initially diagnosed with early-stage disease. Additionally, we found that melanomas in some specific body sites were likely to metastasize to certain organs. Our finding that a substantial proportion of patients with metastases were initially diagnosed with early-stage disease highlights the need to investigate who these high-risk patients are.

Abstract

The characteristics and disease patterns of primary stage I and II cutaneous melanomas that progress to stage III or IV disease were investigated based on data from the Netherlands Cancer Registry (NCR). Data on stage III or IV melanomas at first diagnosis or during follow-up between 2017 and 2019 were retrieved. Patient and primary tumour characteristics were investigated in relation to time to disease progression and the number of organ sites with metastatic disease using regression models. In total, 2763 patients were included, of whom 1613 were diagnosed with stage IV disease. Among the patients with stage IV disease, 60% (n = 963) were initially diagnosed with stage I or II disease. The proportion of patients who received a sentinel lymph node biopsy increased after the introduction of adjuvant therapy in 2019 from 61% to 87%. Among all patients with stage III disease who were eligible for adjuvant systemic therapy (n = 453) after 2019, 37% were not treated with this therapy. Among patients with stage IV disease, lung metastases were most often detected as the first metastatic site and females presented with more metastatic sites than males. Most patient and primary tumour characteristics were not associated with the distant metastatic organ site, except melanoma localisation in the lower extremities and the head or neck. Our observation that most stage IV patients were initially diagnosed with early-stage disease highlights the need for more accurate risk prediction models.

Cutaneous melanoma dissemination is dependent on the malignant cell properties and factors of intercellular crosstalk in the cancer microenvironment (Review)

The incidence of cutaneous malignant melanoma has been steadily increasing worldwide for several decades. This phenomenon seems to follow the trend observed in many types of malignancies caused by multiple significant factors, including ageing. Despite the progress in cutaneous malignant melanoma therapeutic options, the curability of advanced disease after metastasis represents a serious challenge for further research. In this review, we summarise data on the microenvironment of cutaneous malignant melanoma with emphasis on intercellular signalling during the disease progression. Malignant melanocytes with features of neural crest stem cells interact with non‑malignant populations within this microenvironment. We focus on representative bioactive factors regulating this intercellular crosstalk. We describe the possible key factors and signalling cascades responsible for the high complexity of the melanoma microenvironment and its premetastatic niches. Furthermore, we present the concept of melanoma early becoming a systemic disease. This systemic effect is presented as a background for the new horizons in the therapy of cutaneous melanoma.

Clinicopathological Characteristics and Short-Term Survival Analyses of Cutaneous Malignant Melanoma

Objective

Cutaneous malignant melanoma (CMM) arises from melanocytes, which are pigment-producing cells in the skin. CMM constitutes less than 5% of all cutaneous malignancies worldwide but is associated with the highest mortality rate among all skin cancers. The objective of this study was to examine the profile of clinicopathological factors, survival analyses, recurrence rate, metastatic rates, and the management of CMM at Shaukat Khanum Memorial Cancer Hospital and Research Centre (SKMCH&RC) in Lahore, Pakistan.

Methodology

All patients with a diagnosis of CMM treated at our institute from 2014 to 2017 were included in the study. Demographic variables and clinicopathological characteristics were collected and short-term oncological outcomes were recorded. All data were entered and analyzed in SPSS Statistics version 21 (IBM, Armonk, NY).

Results

A total of 28 patients were included in the study. The median age of the patients was 46.5 ±15.9 years. There were 16 male and 12 female patients. A family history of melanoma was present in 7.1% (n=2) of the patients. All patients had a mean survival of 13.43 ±9.09 months. The lower limb was the most common site of tumor among all patients, accounting for 46.4% (n=13) of the cases. On histopathological analyses, ulceration was seen in 53.6% (n=15) of the patients. Unclassified tumor type was present in 75% (n=21) of the patients, followed by nodular in 21.4% (n=6), and superficial spreading in 3.5% (n=1). Clark level IV was the most common presentation, constituting 46.4% (n=13) of the cases. Metastasis was seen in 50% (n=14) of the patients. Local recurrence was observed in 60.7% (n=17) of the patients; 64.3% (n=18) of the patients were alive after one year of treatment.

Conclusion

CMM is a disease with very high fatality rates. Although it is a disease commonly associated with fair-skinned populations, the incidence of CMM is rising in our part of the world as well. Early diagnosis and prompt management of the disease are crucial in its treatment. However, the mortality rate associated with this disease is still not favorable.

Replacement and desmoplastic histopathological growth patterns in cutaneous melanoma liver metastases: frequency, characteristics, and robust prognostic value

Among visceral metastatic sites, cutaneous melanoma (CM) metastasises initially to the liver in ~14-20% of cases. Liver metastases in CM patients are associated with both poor prognosis and poor response to immunotherapy. Histopathological growth patterns (HGPs) of liver metastases of the replacement and desmoplastic type, particularly from colorectal cancer and uveal melanoma (UM), may impart valuable biological and prognostic information. Here, we have studied HGP in 43 CM liver metastases resected from 42 CM patients along with other prognostic factors from three institutions. The HGPs (replacement, desmoplastic, pushing) were scored at the metastasis-liver interface with two algorithms: (1) 100% desmoplastic growth pattern (dHGP) and any (≥1%) replacement pattern (any-rHGP) and (2) >50% dHGP, >50% rHGP or mixed (<50% dHGP and/or rHGP, pushing HGP). For 1 patient with 2 metastases, an average was taken to obtain 1 final HGP yielding 42 observations from 42 patients. 22 cases (52%) had 100% dHGP whereas 20 (48%) had any replacement. Cases with rHGP demonstrated vascular co-option/angiotropism. With the development of liver metastasis, only rHGP (both algorithms), male gender and positive resection margins predicted diminished overall survival (p = 0.00099 and p = 0.0015; p = 0.034 and p = 0.024 respectively). On multivariate analysis, only HGP remained significant. 7 of 42 (17%) patients were alive with disease and 21 (50%) died with follow-up after liver metastases ranging from 1.8 to 42.2 months (mean: 20.4 months, median: 19.0 months). 14 (33%) patients with previously-treated metastatic disease had no evidence of disease at last follow up. In conclusion, we report for the first time replacement and desmoplastic HGPs in CM liver metastases and their prognostic value, as in UM and other solid cancers. Of particular importance, any rHGP significantly predicted diminished overall survival while 100% dHGP correlated with increased survival. These results contribute to a better understanding of the biology of CM liver metastases and potentially may be utilised in managing patients with these metastases.

Malignant Cutaneous Melanoma: Updates in PET Imaging

BACKGROUND

Cutaneous malignant melanoma is a neoplasm whose incidence and mortality are dramatically increasing. 18F-FDG PET/CT gained clinical acceptance over the past 2 decades in the evaluation of several glucose-avid neoplasms, including malignant melanoma, particularly for the assessment for distant metastases, recurrence and response to therapy.

OBJECTIVE

To describe the advancements of nuclear medicine for imaging melanoma with particular attention to 18F-FDG-PET and its current state-of-the-art technical innovations.

METHODS

A comprehensive search strategy was used based on SCOPUS and PubMed databases. From all studies published in English, we selected the articles that evaluated the technological insights of 18FFDG- PET in the assessment of melanoma.

RESULTS

State-of-the-art silicon photomultipliers based detectors ("digital") PET/CT scanners are nowadays more common, showing technical innovations that may have beneficial implications for patients with melanoma. Steady improvements in detectors design and architecture, as well as the implementation of both software and hardware technology (i.e., TOF, point spread function, etc.), resulted in significant improvements in PET image quality while reducing radiotracer dose and scanning time.

CONCLUSION

Recently introduced digital PET detector technology in PET/CT and PET/MRI yields higher intrinsic system sensitivity compared with the latest generation analog technology, enabling the detection of very small lesions with potential impact on disease outcome.

Small bowel obstruction due to intraluminal metastasis from malignant melanoma

The most common form of presentation of malignant melanoma is cutaneous. However, it is important to notice that it can occur in any part of the body, mostly from metastatic route. Gastrointestinal forms of symptomatic metastasis are rare, making it sometimes difficult to diagnose. We present a rare case of an 84-year-old female with a small bowel obstruction due to melanoma metastasis. She was treated with an enterectomy, with no surgical or post-operative complications. Although surgery should be reserved from symptomatic patients, some authors refer to it as a palliative treatment with improvement in long-term survival.

Relapse patterns in patients with local and regional cutaneous melanoma

BACKGROUND

The differences in features and risk factors for recurrence after definitive surgical excision are yet to be determined. The aim of this study was to understand these factors influencing recurrence patterns with local and regional disease in these patients.

METHODS

A total of 365 relapsed patients, of whom 196 presented with local disease (stage I-II) and 169 with regional disease (stage III), were investigated in this retrospective study.

RESULTS

The median time to initial recurrence for stage I-II and stage III patients was 22.3 and 13.4 months, respectively. Stage III patients were found to have higher Clark levels (p = 0.0001) and thicker lesions (p = 0.0001), and they were more significantly associated with the absence of tumor-infiltrating lymphocytes (p = 0.02) than stage I-II patients. Stage III patients were more significantly associated with recurrences compared to the stage I-II patients (p = 0.0001). Locoregional relapses were significantly associated with stage I-II melanomas, whereas majority of the distant metastases occurred in stage III patients (p = 0.01). Pulmonary metastasis was most frequently observed and the distribution of the sites for distant metastases was similar in both groups of the patients. On univariate analysis, male sex, increased tumor depth, presence of ulceration, nodular histopathology, higher Clark level, higher mitotic rate, and presence of lymphovascular invasions were found to predict shorter time to relapse for stage I-II patients; whereas only nodular pathology, presence of ulceration, and high mitotic rate were found to be associated with poor relapse-free survival in stage III patients. However, on multivariate analysis, only mitotic rate maintained its significance for both clinical staging groups.

CONCLUSION

Potential differences among early-stage melanoma patients, who developed recurrence, were noted and mitotic rate was found as the single significant prognostic factor for recurrence in both stage I-II and III patients.

New insights in melanoma biomarkers: long-noncoding RNAs

Melanoma is one of the leading cancers worldwide, distinguished for its malignancy and low survival rates. Although the poor outcome could improve with an early diagnosis and a good monitoring of the disease, current melanoma biomarkers display several limitations which make them useless. Interestingly, long-noncoding RNAs are secreted into the bloodstream inside exosomes by a wide range of malignant cells, and several of them have been validated as promising circulating molecular signatures of other tumors, but not melanoma. In this review we propose to explore the booming field of long-noncoding RNAs in order to find potential candidates to be tested as novel melanoma biomarkers, with the ultimate goal of improving melanoma detection, diagnosis and prognosis.

Effects of inhibition of hedgehog signaling on cell growth and migration of uveal melanoma cells

The Hedgehog (Hh) signaling pathway has been demonstrated to play a critical role in controlling embryonic development, tissue patterning, wound healing and a variety of cell functions. Aberrant activation of Hh signaling is implicated in the pathogenesis of many human cancers, and in angiogenesis. However, the role of this pathway in uveal melanoma (UM) carcinogenesis remains unknown. In this study, we investigated the effects of Hh inhibition using the specific Smoothened (Smo) antagonist cyclopamine to block Hh signaling in cultured human UM cell lines expressing Hh signaling components. Cyclopamine treatment effectively increased apoptosis and inhibited cell proliferation, migration, and epithelial-to-mesenchymal transition (EMT) by downregulating the Hh final arbiter glioblastoma 1 (Gli1), which regulates the transcription of target genes in the nucleus. Changes in gene and protein expression levels were detected by real-time PCR and by western blotting and immunocytochemistry, respectively. Cell cycle and apoptosis regulation induced by cyclopamine were demonstrated by flow cytometry. In addition, the migration capability of UM cells was reduced, as demonstrated by transwell migration and scratch assays. The effects of Hh inhibition on the levels of angiogenesis factors secreted by UM cells were examined by tube-formation assay.

CONCLUSION

Blocking the Hh pathway by cyclopamine decreased cell viability, migration, EMT, and angiogenesis, increased apoptosis, and induced G 1 phase cell cycle arrest in UM cells. Collectively, these results provide the first evidence of the significance of Gli1 activation downstream of Smo as a therapeutic target and the potential value of cyclopamine for the treatment of human UM.