Pigmented Nail Lesions: When to Observe, When to Biopsy, When to Widely Excise, and When to Amputate?

Pigmented nail lesions are challenging problems. The differential diagnosis is broad and ranges from common self-limiting conditions, such as subungual hematoma and infection, to potentially fatal conditions, such as subungual melanoma. Clinical assessment and adjuncts, such as dermoscopy and imaging, are usually insufficient to establish a diagnosis, and a nail bed biopsy is often required. However, this is not an innocuous procedure and may result in permanent nail deformity. In addition, subjecting every patient with nail pigmentation to a biopsy will result in an unacceptably high rate of negative test results. Furthermore, histopathologic diagnosis of subungual melanoma remains challenging for several reasons. Once the diagnosis of subungual melanoma is established, the definitive treatment is controversial because the existing guidelines have largely been adapted from those for cutaneous melanoma. This review presents an approach to the diagnosis and management of pigmented subungual lesions and subungual melanoma, in particular, on the basis of the latest available evidence.

Unusual Presentations of Eccrine Porocarcinomas.

Eccrine porocarcinomas (EPCs) are rare tumours, albeit the most common malignant adnexal tumours of the skin. They can present with very heterogeneous clinical and dermoscopic features, rendering diagnosis limited to histopathological examination alone. We share 2 cases of EPCs, one of which arose in a patient with a prior diagnosis of cutaneous squamous cell carcinoma (SCC) and another whose EPC was likely a malignant transformation of an existing poroma. An occurrence of porocarcinoma after the diagnosis of SCC may suggest the possibility of unknown risk factors for both. Positivity to androgen, oestrogen, and epidermal growth factor receptors was seen in a proportion of porocarcinomas, and this may prompt further research on combination therapy between conventional treatment modalities with hormone receptor antagonists. Malignant change of a poroma may be a more common phenomenon than we would expect based on the current literature.

Extensive Lepromatous Lymphadenitis Preceding Lesions on the Face and Earlobes: An Unusual Presentation of Leprosy in Singapore.

Leprosy is also known as Hansen disease, as in some countries the diagnosis of leprosy carries a negative stigma and patients fear being shunned as outcasts. Presently, leprosy is primarily limited to specific geographical regions in resource-poor countries. As a result, there is increased difficulty for the younger generation of physicians today to correctly identify leprosy due to a lack of exposure and a low-index of suspicion, particularly in developed countries. In this case, the indurated lesions over the face demonstrated a preference for the outer lateral aspects over the maxillary areas, the nose bridge, and the pinna of the ears consistent with the organism's preference for cooler regions of the body. This was also evident in the other skin lesions affecting the more acral regions of the limbs in the early stage of disease progression. There is a need to keep this infective condition as an alternate diagnosis to all unusual cutaneous lesions.