It is said that as many as 50,000 people in the united states have paraneoplastic syndrome. It is a side effect from having cancer, which is why it is so popular.

Samir K. Bhattacharya has written:

'Paraneoplastic syndromes, resulting from elaboration of ectopic hormones, antigens, and bizarre toxins' -- subject(s): Paraneoplastic syndromes

These disorders typically affect middle-aged to older people and are most common in patients with lung, ovarian, lymphatic, or breast cancer.

Most paraneoplastic syndromes are rare, affecting less than 1% of persons with cancer. Exceptions include LEMS, which affects about 3% of patients with small-cell lung cancer; MG, which affects about 15% of persons with thymoma.

About half of all cases are associated with a cancerous tumor; this kind of symptom that occurs due to cancer is termed a paraneoplastic syndrome.