<P> Some 1990s studies indicated that persons with sarcoidosis appear to be at significantly increased risk for cancer, in particular lung cancer, lymphomas, and cancer in other organs known to be affected in sarcoidosis . In sarcoidosis - lymphoma syndrome, sarcoidosis is followed by the development of a lymphoproliferative disorder such as non-Hodgkin lymphoma . This may be attributed to the underlying immunological abnormalities that occur during the sarcoidosis disease process . Sarcoidosis can also follow cancer or occur concurrently with cancer . There have been reports of hairy cell leukemia, acute myeloid leukemia, and acute myeloblastic leukemia associated with sarcoidosis . Sometimes, sarcoidosis, even untreated, can be complicated by opportunistic infections . </P> <P> Sarcoidosis most commonly affects young adults of both sexes, although studies have reported more cases in females . Incidence is highest for individuals younger than 40 and peaks in the age - group from 20 to 29 years; a second peak is observed for women over 50 . </P> <P> Sarcoidosis occurs throughout the world in all races with an average incidence of 16.5 per 100,000 in men and 19 per 100,000 in women . The disease is most common in Northern European countries and the highest annual incidence of 60 per 100,000 is found in Sweden and Iceland . In the United Kingdom the prevalence is 16 in 100,000 . In the United States, sarcoidosis is more common in people of African descent than Caucasians, with annual incidence reported as 35.5 and 10.9 per 100,000, respectively . Sarcoidosis is less commonly reported in South America, Spain, India, Canada, and the Philippines . There may be a higher susceptibility to sarcoidosis in those with celiac disease . An association between the two disorders has been suggested . </P> <P> There also has been a seasonal clustering observed in sarcoidosis - affected individuals . In Greece about 70% of diagnoses occur between March and May every year, in Spain about 50% of diagnoses occur between April and June, and in Japan it is mostly diagnosed during June and July . </P>

Abnormal condition of blood in a joint is called