Section 31(2)(c) in The M.P. Civil Services (Leave) Rules, 1977
(c)Up to eighteen months where the Government servant who has completed one year's continuous service is undergoing treatment(i)Cancer, or for mental illness, in an institution recognised for the treatment of such disease or by a Civil Surgeon, Staff Surgeon or a Specialist in such disease;(ii)Pulmonary tuberculosis or pleurisy of tubercular origin, in a recognised sanatorium.