Carcinomatous involvement of the pelvic nerves (Pelvic Carcinomatous Neuropathy-PCN-) causes disabling sensorial and motor disturbances of the lower extremities. Recurrent rectal carcinomas are the most common cause of PCN because surgical obliteration of the perirectal fascia. In 31 cases of PCN Authors describe the types of the neoplasm and the sites of involvement of the pelvic nerves evaluating clinical syndromes and Computed Tomography. The results of radiotherapy (doses between 36-56 Gy) in 14 cases of PCN by recurrent rectal cancer are also reported. Although the survival of such patients is poor, radiotherapy has obtained a good palliative result in 50% of them. Personalization of radiation treatment planning is advisable in order to avoid acute side-effects.