What You Should Know About Potentially Malignant Wounds
A: Drs. Goss and Minhas categorize the origins of malignant lesions in the foot and ankle in three groups: soft tissue, osseous and distant metastasis. Soft tissue malignancies are more common than osseous counterparts, according to Drs. Goss and Minhas. Malignant soft tissue lesions are derived from ectoderm and include processes from the integument (skin) and glands. They note the common appearance of malignant melanomas (five types: superficial spreading, basal cell, acral lentiginous, lentigo and amelanotic).
All the panelists cite squamous cell carcinoma as common in their facilities with Dr. Bakotic seeing that malignancy daily. Drs. Goss, Bakotic and Minhas also note the common occurrence of basal cell carcinoma.
Less common malignant skin lesions include verrucous carcinoma and Marjolin’s ulceration, concur Drs. Goss and Minhas. They also note that malignant osseous lesions and sarcomas (derived from the mesoderm) are far less common in the lower extremity. Dr. Goss and Dr. Minhas point out that sarcomas that usually present in the foot and ankle include Kaposi’s sarcoma, synovial sarcoma, malignant Schwannoma, osteosarcoma, malignant fibrous histiocytoma, liposarcoma, clear cell sarcoma and, to a lesser extent, fibrosarcomas.
In the pediatric population, they concur that Ewing’s sarcoma and rhabdomyosarcoma are the main etiology. Distant metastasis in the foot and ankle is extremely uncommon. They note that the four most common sites are the lung, bladder, breast and kidney.
Dr. Bakotic notes that since melanomas manufacture abundant brown-black pigment in most cases, physicians are less likely to confuse these lesions with non-neoplastic wounds. However, he says amelanotic melanoma nearly uniformly presents as a non-healing ulceration. Less commonly, he encounters neoplasms such as diffuse large B-cell lymphoma, Merkel cell carcinoma and adnexal carcinoma masquerading as benign ulcerations.
Q: Do you have any insights into how and when to biopsy these wounds?
A: If such wounds are not healing, Dr. Morse takes biopsies. From the start, his treatment plan entails taking biopsies of patients with chronic wounds.
Generally, Dr. Bakotic says for the purpose of histopathologic analysis, one should sample any ulceration that arises spontaneously. For ulcers that appear to occur in concordance with a bona fide causative condition but fail to improve despite appropriate therapy, he says one should sample them after roughly two to three months. Dr. Bakotic warns that failure to sample neoplastic ulcers after two to three months of targeted care could result in establishing causation.
If one encounters superficial wounds that appear to be benign, Drs. Goss and Minhas say one can perform a shave biopsy or a punch biopsy (especially for subungual lesions). They note that physicians can perform fine needle and core biopsies in the office but emphasize getting enough of a specimen for analysis. Physicians may do excisional biopsies for smaller lesions they suspect of being benign whereas incisional biopsies are best for larger lesions that one suspects to be malignant. For any wound suspected of malignancy, they say one should biopsy it as soon as possible to ensure accurate and timely diagnosis, and to facilitate proper care.
Q: When is amputation a consideration?