Retrorectal cyst-hamartomas: CT diagnosis.

Retrorectal cyst-hamartomas (RRCH) are congenital lesions characterized by the presence of cysts lined by multiple types of epithelium, often predominantly mucin-secreting. Three cases of RRCH are presented with their associated histologic and CT findings. The lesion requires complete surgical excision to prevent complications of recurrence, infection, or metastasis.