Cutaneous and systemic malignancies in patients with sarcoidosis: a close association.

Dear Editor, The article by Ji et al1 is very interesting. However, they do not mention the increased risk for systemic malignancies especially cutaneous malignancies in patients with sarcoidosis. The incidence of malignancies in patients with sarcoidosis is almost 1.65 times the incidence in patients without any clinical sarcoidosis.2 In fact, patients with sarcoidosis are almost 3 times more likely to develop nonmelanoma skin cancers compared to patients without sarcoidosis.3 Besides non-melanoma skin cancers, patients are also at an increased risk for developing melanomas. Besides skin cancers, sarcoidosis is also associated with an increased incidence of other systemic malignancies especially haematological malignancies. Haematological malignancies commonly seen in patients with sarcoidosis include B cell lymphomas, Hodgkin’s lymphomas, chronic myeloid leukaemias and chronic lymphoid leukaemias.4 Patients may even develop tumours such as MALT (Mucosal Associated Lymphoid Tissue) lymphoma. Cauvain et al5 recently described the case of a 59-year-old female with sarcoidosis who developed a MALT lymphoma of the lower eyelid. Similarly, sarcoidosis is also associated with an increased incidence of solid malignancies such as lung and hepatocellular carcinomas as well as other systemic solid tumours.6 May et al7 recently reported 3 cases of patients with sarcoidosis who developed testicular cancer. Patients may even have multiple co-existing malignancies. Romero et al8 reported a patient with sarcoidosis and coexisting epidermoid carcinoma and lymphoma. The increased incidence of haematological and solid malignancies in patients with sarcoidosis is most likely secondary to the chronic systemic inflammation that individuals with sarcoidosis are prone to.9 Given the fact that the systemic symptoms of sarcoidosis may mask the symptoms of malignancies makes the diagnosis all the more difficult. Physicians should be aware of the close association between sarcoidosis and systemic malignancies, especially skin cancers, so as to decrease the high morbidity and mortality associated with sarcoidosis. Cutaneous and Systemic Malignancies in Patients with Sarcoidosis: A Close Association