Melanoma of the Foot Is Associated With Advanced Disease and Poorer Survival

Malignant Melanoma of the Foot in Five Elderly Patients: Clinicopathologic Features and Treatment Outcomes

Malignant melanoma, an aggressive neoplasm of melanocytes, remains a leading cause of skin cancer-related deaths globally, with rising incidence among elderly populations. Foot melanomas are often diagnosed at advanced stages due to delayed detection and misdiagnosis. They exhibit poorer outcomes compared to melanomas at other sites. This case series presents five elderly patients (ages 58-80) with malignant melanoma of the foot, detailing their clinicopathological features, treatment strategies, and outcomes. All cases presented with advanced disease, emphasizing the challenges of late diagnosis in this demographic. Histopathological evaluation confirmed nodular, superficial spreading, and acral lentiginous subtypes, with Breslow thicknesses ranging from 1.5 mm to 3.5 cm. Management involved wide local excision, lymph node dissection, and adjuvant chemotherapy in high-risk cases. Recurrence occurred in one patient, underscoring the aggressive nature of the disease. The series highlights the necessity of early detection, multidisciplinary care, and tailored adjuvant therapies to improve outcomes in elderly patients with foot melanoma.

Distribution Patterns of Tumors and Tumor-Like Lesions of the Forefoot and Midfoot A 12.5-Year Study at a University Hospital

BACKGROUND

Masses in the forefoot and midfoot are common reasons for medical presentation and can be caused by various pathological conditions. The challenge in clinical practice is to distinguish the multitude of trivialities from the few malignant entities and to arrive at a reliable clinical diagnosis in a reasonable amount of time with a moderate use of diagnostic tools.

MATERIAL AND METHODS

In a retrospective analysis, tumors, tumor-like lesions, and pseudotumors distal to the Chopart joint presented to our multidisciplinary university tumor board between January 2010 und June 2023 were analyzed concerning entity, location, age, and sex.

RESULTS

Of the 167 cases included, 18 were osseous and 149 were soft tissue lesions. Overall, the metatarsal region was most frequently affected, accounting for 42.5% of all cases. Osseous lesions showed a preference for the phalanges and soft-tissue lesions occurring more frequently in the metatarsal region. In total, 88.0% of all cases were benign. All 20 malignant cases derived from soft tissue, occurred in all sections of the forefoot and midfoot and comprised 13 entities. Most lesions affected middle-aged patients, but cases occurred in almost every age group.

CONCLUSION

In the examined patient population of a German university hospital, most cases were benign soft tissue lesions with a substantial share of pseudotumors and tumor-like lesions. However, the malignancy rate of 12.0% highlights the importance of differential diagnostic considerations. In cases of uncertain results, it is crucial to refer individuals with unclear masses to a specialized center for musculoskeletal tumor care early on in their treatment process.

LEVELS OF EVIDENCE

III.

Silencing Exosomal circ102927 Inhibits Foot Melanoma Metastasis via Regulating Invasiveness, Epithelial-Mesenchymal Transition and Apoptosis

Background

Exosomes contain abundant circular RNAs (circRNAs), playing an important role in intercellular communication. However, the function and underlying molecular mechanism of exosomal circRNAs in foot metastatic melanoma remain unclear.

Methods

Twelve differentially expressed exosomal circRNAs between patients with metastatic and primary foot melanoma were screened through high-throughput sequencing, and their expression levels were detected by the real-time reverse transcriptase-polymerase chain reaction (RT-qPCR). CircRNA102927 silencing and overexpression A2058 cell line was constructed, and the effects of circRNA102927 on cell proliferation, apoptosis, migration, invasion, and epithelial-mesenchymal transition (EMT) were assessed using cell counting kit-8 (CCK-8), flow cytometry, wound healing, Transwell, and Western blot assays, respectively.

Results

Twelve differentially expressed exosomal circRNAs were screened and ROC curve showed that six circRNAs could be used as the diagnostic biomarkers for metastatic melanoma. Melanoma-secreted exosomes induced the differentiation of CD4+ T cells into Treg cells. CircRNA102927 was highly expressed in metastatic melanomas. Functionally, circRNA102927 silencing inhibited proliferation, EMT, migration, and invasion in metastatic melanoma cells, while promoting apoptosis. Meanwhile, overexpression of circRNA102927 had the opposite effects.

Conclusion

Our investigation suggests that silencing exosomal circRNA102927 may suppress foot melanoma metastasis by inhibiting invasiveness, EMT and promoting apoptosis.

Insights into the Distribution Patterns of Foot and Ankle Tumours: Update on the Perspective of a University Tumour Institute

The rarity of foot and ankle tumours, together with the numerous histological entities, presents a challenge in accumulating sufficient patients to draw reliable conclusions. Therefore, we decided to present an update of a retrospective analysis of their distribution patterns, comprising 536 cases of foot and ankle tumours presented to our tumour board between June 1997 and June 2023. Our aim was to provide a comprehensive overview of the prevalence and distribution patterns of benign and malignant bone and soft tissue tumours of the foot and ankle. A total of 277 tumours involved bone (51.7%). Of these, 242 (87.4%) were benign and 35 (12.6%) were malignant. In addition, 259 soft tissue tumours (48.3%) were found, of which 191 (73.7%) were benign and 68 (26.3%) were malignant. The most common benign bone tumours were simple bone cysts, enchondromas, osteochondromas, aneurysmal bone cysts, and lipomas of bone. Common benign soft tissue tumours included a tenosynovial giant cell tumour, haemangioma, plantar fibromatosis, schwannoma, and lipoma. The most common malignant soft tissue tumours were synovial sarcoma, malignant melanoma, and myxofibrosarcoma. In terms of anatomical location, the hindfoot was the most common site (28.7%), followed by the midfoot (25.9%), ankle (25.4%), and forefoot (20.0%). The distribution of benign entities often follows typical patterns, which may facilitate an early diagnosis even without biopsy (e.g., simple bone cyst, plantar fibromatosis). On the other hand, the distribution patterns of many rare or malignant entities are inconsistent. Individual soft tissue malignancies occur very sporadically, even over long periods of time and in specialized tumour centres. It is therefore important to recognise that any suspicious mass in the foot and ankle must be considered a possible malignancy until proven otherwise.

Limb melanomas: acral melanomas have worse survival

BACKGROUND

The anatomic site of primary melanoma is significantly correlated with survival, and extremity melanomas have better prognosis than trunk or head and neck melanomas.

AIM

The aim of this study was to review and evaluate the prognostic factors and survival outcomes associated with both upper and lower extremity melanomas.

METHODS

A total of 524 limb-located melanomas were analyzed retrospectively.

RESULTS

Lower extremity melanomas were predominant in number and feet/toes melanomas were more frequently found in the elderly. Acral lentiginous melanomas were found to affect more frequently lower limbs and showed mainly distal distributions for both limbs. However, acral melanomas were more often ulcerated and they were more frequently BRAF wild-type melanomas associated with significant lymphovascular invasion. Foot and toe melanomas relapsed more frequently than leg melanomas. The 5-year overall survival rates for upper and lower limbs were the same, 62%. The finger (p = .0001) and toe (p = .005) melanomas had worse overall survivals than arm and leg melanomas, respectively. Both overall and disease-free survivals of acral melanoma patients were found worse than those of nonacral melanoma patients, p = .0001 and p = .001 respectively. Despite not having adjusted by Breslow, ulceration and nodal involvement status, acral location per se could be associated with poorer outcome in our retrospective study.

CONCLUSION

Even though they were not found to be correlated with major predictors of poor prognosis, acral melanomas significantly predict poor survival.

Digit melanomas are associated with poor prognostic factors and unfavorable survivals

BACKGROUND

The anatomic location of primary melanoma is significantly associated with outcome.

OBJECTIVE

To evaluate the prognostic factors and survival outcomes associated with melanomas on hand and foot digits.

METHODS

The data of 106 patients with digit melanomas were analyzed retrospectively.

RESULTS

Median age of patients was 55 years, and male-to-female ratio was one. Majority of the patients had skin melanomas (74.5%); and 25.5% of them had ungual melanomas. The lesions slightly more frequently affected toes (53.8%) and thumbs (55.9%); and 57.4% of the lesions were right-sided. Acral lentiginous melanoma was the major histological subtype (67.5%). Digit melanomas were associated with aggressive histological features, such as high Clark level (75%), thick Breslow depth (72.3%), presence of ulceration (74.3%), and high mitotic rate (58.3%). At admission, the rates of stage I-II, stage III, and stage IV diseases were 57.6%, 33%, and 9.4%, respectively. The recurrence and mortality rates were 41.7% and 46.2%, respectively. The 5-year RFS and OS rates were similar: 47%. Melanoma origins (skin vs. ungual), locations (finger vs. toe; first digit vs. others; and right vs. left), and histological subtypes (acral lentiginous melanoma vs. others) had no impact on survivals. The known poor prognostic histological factors, such as Clark level, Breslow thickness, mitotic rate, ulceration, and neurotropism, were found to be associated with both RFS and OS.

CONCLUSION

Digit melanomas are associated with poor clinicopathological prognostic features, and they might predict unfavorable survivals.

Differences by Anatomical Site of Non-Acral Lentiginous Melanomas of the Lower Limb

BACKGROUND

Acral location of melanomas is associated with poor survival. It can be due, at least in part, to the fact that acral lentiginous melanoma, a distinct melanoma subtype, has a particular biological profile and a bad clinical behavior. However, since almost 50% of acral melanomas are not of acral lentiginous melanoma subtype, the worse clinical behavior could also be attributable to the intrinsic characteristics of the location.

OBJECTIVE

This study aimed to investigate if melanomas of the lower limb excluding acral lentiginous melanoma differ by location.

METHODS

This retrospective, observational study recruited patients from an oncology referral center in Spain. We included 285 patients with superficial spreading and nodular melanomas of the lower limb. We compare melanomas by site, clinical and pathological characteristics, and the differences by location of disease-free and melanoma-specific survival by the Kaplan-Meier method and Cox proportional hazard method.

RESULTS

Patients with melanomas on the foot, compared to those on the rest of the limb, were older and reported having suffered less sunburns; the melanoma more frequently appeared in areas that had been rarely sun exposed, were more frequently of nodular type, presented thicker tumors, with more ulceration, less regression, and more advanced stage of the disease. Foot location increased the risk of relapse and decreased melanoma-specific survival.

CONCLUSION

Melanoma development in foot is less related to sun exposure and is associated with pathological features that can account for the worse prognosis and poorer survival.

Malignant tumours of the foot and ankle

Tumours of the foot and ankle constitute about 4-5% of all musculoskeletal tumours with the majority of them being benign. Diagnosis of malignant soft tissue or bone tumours is frequently delayed because of the relatively low prevalence and uncommon presentation at the foot and ankle. Suspicious lesions or lumps should be subjected to CT, MRI and biopsy. Subfascial location, lump size more than 5 cm, increase in size, painful and recurrent tumours should raise the suspicion of malignancy and lead to patient referral to a designated tumour centre. Neoadjuvant and adjuvant systemic chemotherapy and/or radiation therapy, isolated limb perfusion (ILP) and hyperthermia for malignant tumours have to be discussed in a multidisciplinary tumour board. With the advances in local and free tissue transfer, limb-sparing techniques have increasingly replaced primary amputations thus preserving lower limb function as much as possible without compromising on the principles of oncologic resection.