Callus or Pressure Ulcer: This is often due to repetitive friction or pressure on the palm, leading to thickening of the skin as a protective response. However, if the pressure continues, it can lead to ulceration and become a non-healing lesion.

Dupuytren's Contracture: Although primarily known for causing contracture of the palmar fascia, Dupuytren's can sometimes present with nodules or lesions on the palm that may not heal properly due to the underlying fibrotic process.
Squamous Cell Carcinoma (SCC): SCC can occur on the palm, especially in areas exposed to chronic irritation or in individuals with a history of significant sun exposure. It may present as a non-healing ulcer or lesion.
Eczema/Dermatitis: Chronic eczema or dermatitis on the palm can lead to thickened, scaly skin that may appear as a non-healing lesion, especially if there's ongoing exposure to irritants or allergens.

Malignant Melanoma: Although less common on the palms compared to other skin areas, melanoma can occur here and may present as a changing or non-healing lesion. Early detection is crucial for survival.
Sporotrichosis: A fungal infection that can enter the body through cuts or abrasions on the skin, often acquired from soil or plants. It can cause lesions that do not heal and may spread along lymphatic channels.
Cutaneous Leishmaniasis: In endemic areas, this parasitic infection can cause skin lesions that may not heal, transmitted by the bite of an infected sandfly.

Keratoacanthoma: A rare, low-grade malignancy that can appear as a firm, round, skin-colored to red growth, which may resolve on its own but can resemble a non-healing lesion.
Glomus Tumor: A rare, usually benign tumor of the glomus body, which can occur under the nail or on the palm, presenting as a painful lesion.
Epidermoid Cyst: While not typically considered a non-healing lesion, if infected or ruptured, an epidermoid cyst on the palm could present in a manner that resembles a non-healing lesion.