Nodular bleeding lesion on the sole revealing a case of Kaposi's sarcoma

El sarcoma de Kaposi (SK) es un trastorno angioproliferativo raro del endotelio vascular que ocurre en personas infectadas con herpesvirus humano-8 [1]. Cuatro subtipos epidemiológicos primarios se describen comúnmente: clásico, relacionado con el SIDA, africano e iatrogénico. En este artículo, presentamos un caso raro de SK nodular en un paciente VIH negativo.

section_content: A 65-year old male, presented to the dermatology clinic with a progressively growing and occasionally bleeding lesion on the sole of his right foot. There was no history of trauma and he was otherwise healthy. The patient declared that these lesions were present for nearly 2 years and was only aware of the lesion when it began to bleed approximately four months before the consultation. On examination, a purplish nodule with clear-cut borders and central ulceration was seen (Fig. 1 ). No other similar lesions were seen elsewhere. Routine laboratory tests were all normal. The anti-HIV test was negative. Histological examination of the biopsy found proliferation of fusiform cells within the dermis, which is associated with inflammatory infiltrate and many vessels. The patient's cells stained positive for human herpesvirus 8, but was negative for melan A and HMB45. As the lesion was solitary, a surgical excision was performed. 

Kaposi sarcoma is a vascular neoplastic disease caused by human herpesvirus 8 infection. Four variants of Kaposi sarcoma have been described, which present with similar cutaneous lesions that vary depending on clinical variant -pink patches to violet plaques in early stages, to nodules or tumoural polyps in later stages [2]. Lesions can be solitary or multiple. 

The four variants differ mainly on the epidemiological aspects and are: African endemic Kaposi sarcoma, Kaposi sarcoma associated with iatrogenic immunosuppression, acquired immune deficiency syndrome (AIDS)-related epidemic Kaposi sarcoma, and classic Kaposi sarcoma, which appears in patients typically after the fifth decade and mainly in males of Mediterranean or Eastern European origin. Classic Kaposi sarcoma presents as slow-growing, red-violet macules on the distal lower extremities that can coalesce to form large plaques, develop into nodules, or even regress spontaneously. Sometimes, nodules are the first clinical observation since macules and plaques are asymptomatic. 

In classic Kaposi sarcoma, which mainly affects immunocompetent patients and typically has a chronic and protracted course, achieving a complete cure might be unrealistic given the frequency of recurrence [3]. For the treatment of solitary lesions, surgical approach or radiotherapy are the preferred options. When multiple lesions are encountered, observation and close follow-up might be an option. Only rapidly progressive (more than 10 or more new cutaneous lesions in a month) or symptomatic visceral involvement require systemic chemotherapy [4].

section_name: Letter to the Editor

section_content: In conclusion, classical KS is generally observed in the lower extremities as multiple lesions while isolated nodular sole lesion has rarely been seen.
section_name: CONCLUSION

section_content: The examination of the patient was conducted according to the Declaration of Helsinki principles.
section_name: Consent