• When otitic cholesteatomas are removed by a surgical method that preserves or reconstructs the bony canal wall and tympanic membranes, there is a risk of incomplete removal and possible regrowth of the lesion. To study the incidence of this complication, 52 patients with cholesteatoma had elective repeated explorations at various postoperative intervals; eight (15.4%) had early cholesteatoma regrowth even though there was no clinical evidence of it. Seven of these regrowths were small and were again surgically removed. It is advocated that conservative surgery for cholesteatoma be followed up in two years by another elective surgical exploration to check for and dispose of possible cholesteatoma regrowth. This would provide safety comparable to that achieved with radical mastoidectomy, with far better function and hearing. The method does necessitate patient understanding and cooperation and I suggest methods of achieving this. (Arch Otolaryngol 103:144-147, 1977)