Clinicopathological, dermoscopic features and circumstances of diagnosis of amelanotic or hypomelanotic melanoma: A prospective multicentric study in the French private medical sector.

BACKGROUND: Amelanotic or hypomelanotic melanomas (AHM) are difficult to diagnose, and are often diagnosed late, with a high Breslow index and a poor prognosis. PATIENTS AND METHODS: A total of 226 volunteer dermatologists consulting in private practice in France completed an online form for each new histologically proven case of melanoma diagnosed at their clinic in 2020. This anonymised survey collected data on the clinical, dermoscopic, and histological features of melanoma, as well as the circumstances of diagnosis and initial management. A group of 145 AHM was single out and compared to the 1503 pigmented melanomas (PM) from the same cohort. RESULTS: 1503 pigmented melanomas (PM) and 145 AHM (8.8% of these melanomas) were identified and included. In the AHM group, the mean age at diagnosis was 65 ±â€¯16 years, with no significant difference from the PM control group. AHM were not predominantly on the face and neck area, and there were no differences based on gender. Warning signs (local progression and bleeding) were significantly more frequent in the AHM group than in the PM group. AHM were more frequently ulcerated and nodular, with a higher median Breslow thickness than in the PM group (1.56 vs. 0.5 mm), and mitoses were more frequent. Dermoscopy was widely used and proved useful for distinguishing benign lesions, and for highlighting the vascular polymorphous pattern of malignant lesions. Patients noticed the suspicious lesion themselves in most cases of AHM (73.2%), as opposed to their general practitioner (17.2%) or entourage (9.5%). A total body skin examination enabled detection of 19.3% of AHM and 21.3% of PM where the patient consulted for another lesion, or for an unrelated reason. CONCLUSION: AHM are difficult to diagnose for the clinician because of the paucity or absence of pigmentary criteria. Knowledge of dermoscopic vascular patterns is critical and could help reduce the median Breslow index of AHM at the time of detection. Self-examination of the skin should be encouraged, and simple algorithms for earlier detection of skin cancers should be promoted among health professionals and the general population.

The combination of dermoscopy and reflectance confocal microscopy increases the diagnostic confidence of amelanotic/hypomelanotic lentigo maligna.

The dermoscopic diagnosis of amelanotic/hypomelanotic lentigo maligna/lentigo maligna melanoma (AHLM/LMM) may be very difficult in its early stages because of lack of pigment. Reflectance confocal microscopy (RCM) is an imaging technique that is especially helpful for the diagnosis of lentigo maligna. To determine the diagnostic performances of dermoscopy and RCM in the diagnosis of AHLM/LMMs we evaluated dermoscopic and RCM images of consecutive cases of histopathologically confirmed AHLM/LMMs, amelanotic/hypomelanotic basal cell carcinoma and squamous cell carcinoma (AHBCCs/AHSCCs), amelanotic/hypomelanotic benign lesions (AHBLs), and actinic keratoses (AKs) from five participating centers. Sensitivity, specificity, accuracy, predictive values, and level of diagnosis confidence were calculated for both diagnostic procedures. Both dermoscopy and RCM showed diagnostic performance >97% in the diagnosis of AHLM/LMMs versus AHBCC/AHSCCs and their combination slightly improved diagnostic performance, with accuracy increasing from 98.0% to 99.1%. Similarly, RCM in combination with dermoscopy showed a tiny increase in the diagnostic performance in the diagnosis of AHLM/LMMs versus AHBLs (accuracy increased from 87.2% to 88.8%) and versus AKs (accuracy increased from 91.4% to 93.4%). Although the increase in diagnostic performance due to RCM was modest, the combination of dermoscopy and RCM greatly increased the level of confidence; high confidence in the diagnosis of AHLM/LMMs versus AHBLs increased from 36.2% with dermoscopy alone to 76.6% with dermoscopy plus RMC. Based on our results, dermoscopy and RCM should be complementary to improve not only diagnostic accuracy but also the level of diagnostic certainty in the diagnosis of AHLM/LMMs.

Primary anorectal amelanotic melanoma with liver, lungs and lymph nodal metastases.

Anorectal melanoma (ARM) is an exceedingly rare and very aggressive malignancy. It originates from the melanocytic cells in the anorectal mucosa, which produces melanin. Other mucosal melanomas commonly found in the mucosa of the oral cavity, vulvovaginal, pharynx and urinary tract. Patients usually present with bleeding per rectum, perianal pain and difficulty in defaecation. Distinction of primary anorectal melanoma from other tumours of this region is difficult because of the lack of common imaging features. MRI is the modality of choice for its better tissue characterisation and resolution. There is no standard treatment protocol available mainly due to scarcity of data. Surgery is the mainstay therapy. Herein we present a case of a male patient in his 30s who presented with rectal bleeding and perianal pain. Haematological analysis revealed normocytic normochromic anaemia. MRI detected a mass lesion in the anorectal region. Contrast enhanced CT revealed multiple metastases in the liver, lungs, periportal, mesorectal and inguinal lymph nodes. The diagnosis of the ulcerated anorectal melanoma was established on histopathological examination. The patient underwent abdominoperineal resection (APR) followed by chemotherapy. Afterward the patient presented to the emergency room with respiratory distress for which he was on ventilator support. Sadly, the patient died after four days.

Amelanotic melanoma in a patient with trisomy 21: clinical and dermoscopic presentation.

Amelanotic melanoma is an uncommon form of melanoma; accounting for 2%-8% of all melanoma cases. In the human population, the incidence of melanoma in patients with trisomy 21 is relatively unknown. It is theorised that having an extra copy of chromosome 21 is protective against melanoma development as people with trisomy 21 also carry an extra copy of the genes on that chromosome including any that protect against cancer. A literature review revealed four other reported cases of cutaneous melanoma in persons with trisomy 21. To the authors' knowledge, this is the first case of amelanotic melanoma presenting in a patient with trisomy 21 and the fifth case of melanoma overall reported in a patient with trisomy 21.This case highlights the need for specialist referral of all new skin lesions where the diagnosis is unclear.

[Fluorescence detection to diagnose melanoma : An alternative objective method for dermatohistology]. / Fluoreszenzbasierte Melanomdiagnostik : Eine flankierende objektive Methode zur Dermatohistologie.

BACKGROUND: Dermatohistological assessment is the gold standard in the diagnosis of melanoma. As a subjective method, this depends, among other things, on the expertise of the examiner. AIM: A new objective method of investigation-dermatohistofluoroscopy-aims to improve the diagnostic reliability of melanoma diagnosis. MATERIALS AND METHODS: The ultra-weak spectrally resolved fluorescence of melanin of pigment-bearing skin cells is a reliable indicator of the malignancy of the tissue to be diagnosed. Using a special laser spectroscopic method, this fluorescence can be measured on histological specimen (and also on tissue in vivo and on excidate). RESULTS AND DISCUSSION: Melanocytes from normally pigmented skin, nevomelanocytes from benign and dysplastic nevi, and melanoma cells each show characteristic, different fluorescence spectra. If these cell types are shown spatially resolved in different colors on the preparation to be diagnosed, they give the histologist an objective basis for the diagnosis, even in difficult cases, e.g., the so-called stumbling blocks of melanoma diagnosis such as Spitzoid tumors. Currently, the method can only be used for Fitzpatrick skin types 1 and 2. In addition, a separate second measurement signal at 400 nm can be used to identify tumor breakthrough through the basement membrane. This signal is collagen bound, so it also appears in amelanotic melanomas, to which the method is otherwise inherently inapplicable.

Neurosarcomatous amelanotic transformation of malignant melanoma presenting as malignant periopheral nerve sheath tumor: Rare case report.

RATIONALE: Malignant melanoma (MM) is notorious for its remarkable morphological variation and aberrant histopathological patterns. In addition, Malignant Periopheral Nerve Sheath Tumor (MPNST) is an uncommon but aggressive soft tissue sarcoma. Because of the common embryological origin of melanocytes and Schwann cells in the neural crest, discriminating between a particular type of MM and MPNST can be difficult, particularly when they are amelanotic. Our goal is to increase awareness among clinicians of the rare variations of MM and the importance of medical history in improving the accuracy of the final clinical diagnosis. PATIENT CONCERNS: A 68-year-old man was admitted to the hospital due to pain in his right ankle, which had persisted for 8 months, along with swelling for 4 months. Medical history revealed delayed healing of right plantar for 5 years after a traumatic injury. DIAGNOSES: The ankle mass was initially diagnosed as MPNST through biopsy. After reviewing the patient's medical history and receiving the final pathological report following amputation, we have revised the diagnosis to metastatic amelanotic desmoplastic melanoma in the ankle part and lentigo maligna melanoma in the plantar part. This is due to both lesions displaying positive markers or mutated genes in immunohistology and Gene Mutation Detection, indicating homology between the 2 tumors. INTERVENTIONS: Due to the malignant characteristics of the tumor and the patient's wishes, amputation of the right lower leg was carried out. OUTCOMES: Subsequently, the patient was treated with interferon-γ and immunosuppressant PD-1 inhibitor, and survived for 1 year after amputation. LESSONS: Clinical data, immunohistochemisty biomarkers and genes detection results can serve as valuable evidence for pathologists and clinicians in identifying the disease process. Collaborative efforts between clinicians and scientists are crucial in order to identify specific markers that can effectively differentiate between the 2 tumors, thereby enhancing the conclusiveness of the diagnosis.

Amelanotic melanomas are often diagnosed at an advanced stage.

In this case report, a 62-year-old woman was diagnosed with lymph node metastasis from melanoma in the groin. Initially the primary tumour was unknown. The entire skin was examined without any suspicious moles. A PET-CT scan showed an area on the left heel with increased activity. The element surprisingly showed an amelanotic melanoma. Amelanotic melanomas have a significantly worse prognosis compared to pigmented melanomas, presumably because they are detected later and may be very difficult to detect clinically. This case shows the importance of paying attention to unpigmented elements when searching for a primary tumour.

Primary vulvar melanoma in an adolescent patient.

Herein we describe the case of a Black adolescent who was found to have widely metastatic melanoma originating from a primary vulvar lesion. The lesion presented as a pink, vegetative nodule of the clitoral hood which grew in size over several years and was confirmed to be melanoma on shave biopsy. This patient's amelanotic presentation in conjunction with the rare incidence of vulvar melanoma contributed to the delay in diagnosis. This case exemplifies the challenge of early recognition of potentially malignant vulvar lesions for primary care providers in adolescents.

Phenolic acids and a static magnetic field change the expression of transforming growth factor ß isoforms in amelanotic melanoma cells.

BACKGROUND: Melanoma is an aggressive type of cancer that can metastasize to numerous other organs. TGFß is one of the key signaling pathways in melanoma progression. Previous studies on various types of cancer have shown that both: polyphenols and a static magnetic field (SMF) can be potential chemopreventive/therapeutic agents. Therefore, the aim of the study was to evaluate the effect of a SMF and selected polyphenols on the transcriptional activity of TGFß genes in melanoma cells. METHODS AND RESULTS: Experiments were performed on the C32 cell line treated with caffeic or chlorogenic acids, and with simultaneous exposure to a moderate-strength SMF. The RT-qPCR method was used to determine the mRNA level of genes encoding the TGFß isoforms and their receptors. The concentration of the TGFß1 and TGFß2 proteins were also measured in the cell culture supernates. The first response of C32 melanoma cells to both factors is the reduction of TGFß levels. Then, mRNA level of these molecules returned to values close to pre-treatment level by the end of experiment. CONCLUSION: Our study results demonstrate the potential of polyphenols and a moderate-strength SMF to support cancer therapy by altering TGFß expression, which is a very promising topic for the diagnosis and treatment of melanoma.