Malignant melanoma - Foot and Ankle

Summary
Description

Primary cutaneous melanoma is the most common malignant tumor of any type in the foot.

People and Age
Most patients are young adults, with the most frequent age at presentation being in the 40s
Brief desc of tx
Thin lesions are excised with a 1 cm margin, intermediate lesions with a 2-cm margins, and a thick lesions with a 3-cm margin. Lesions in the toes are generally treated by amputation.
Tumor Name
malignant melanoma - foot and ankle
Tumor Type
Tumors of the Foot and Ankle
Benign or Malignant
Malignant
Body region
ankle and foot, leg
Most Common Bones
multiple bones
Complete Information on this Tumor
Introduction and Definition

Primary cutaneous melanoma is the most common malignant tumor of any type in the foot. The term acral lentiginous melanoma is applied to melanoma affecting the hand or foot. Despite years of research, the news about malignant melanoma continues to be bad. Not only does malignant melanoma in the foot have a significantly worse prognosis then melanoma in other body sites, but the prevalence of melanoma is increasing faster than that of any other type of cancer. The most common sites of presentation on the plantar surface and subungual regions, but the tumor may occur anywhere on the foot. These lesions are frequently misdiagnosed as benign nevus, subungual hematoma, pyogenic granuloma, and other dermatological lesions. The foot and ankle surgeon should be wary of pigmented lesions seen anywhere on the foot or ankle. Patients with suspicious lesions should be promptly referred for appropriate management. The referral should be made in writing and documented in the chart. Careful documentation and follow-up on all patients referred for potential cancers can increase the chance of early diagnosis and reduce the risk of legal claims related to delay in diagnosis.

Studies have shown that melanoma of the foot tends to present at a more advanced stage and at a greater depth then lesions elsewhere in the body. These factors may be related to frequent delays in diagnosis. Delay in diagnosis is associated with a significant negative impact on survival.

Thin lesions are less than 1 mm, intermediate lesions are up to 4 mm, and the lesions are more than 4 mm. Thickness of the tumor is the single most important prognostic factor. Surgical removal with an operative margin of up to 3 cm is recommended based on the thickness of the tumor.

Incidence and Demographics
Most patients are young adults, with the most frequent age at presentation being in the 40s. Women are more frequently affected than men and this cancer presents a particular risk for young women. This tumor is the most common malignancy in women in their late 20s, and is second only to breast cancer in women in their 30's.
Treatment Options for this Tumor
Thin lesions are excised with a 1 cm margin, intermediate lesions with a 2-cm margins, and a thick lesions with a 3-cm margin. Lesions in the toes are generally treated by amputation. Wide resection with split thickness skin graft coverage or loco-regional flap coverage is necessary for all lesions. Depending on the location and available soft tissue coverage, amputation may be required. Elective regional lymph node dissection can be combined with surgical removal of the primary tumor. Lymph node dissection is used to stage the disease in thick and intermediate tumors, but is controversial in thin tumors and is no longer considered mandatory.
Outcomes of Treatment and Prognosis
Overall survival at 5 years is a 63% and at 10 years is a 51%.