<s>[INST] <<SYS>> This is a medical question of type : frequency <</SYS>> How many people are affected by lymphangioleiomyomatosis ? [/INST] Sporadic LAM is estimated to occur in 2 to 5 per million women worldwide. This condition may be underdiagnosed because its symptoms are similar to those of other lung disorders such as asthma, bronchitis, and chronic obstructive pulmonary disease. </s>