Benign or Low-Grade Malignant Masses Occupying the Pelvic Canal Space in 11 Dogs.

Abstract

Simple SummaryLarge canine pelvic masses, even though benign, can seriously affect dogs’ lives, causing problems regarding defecation and urination, and sometimes complete rectal and/or urethral obstruction. Many of these patients are euthanized owing to their poor clinical condition as a result of chronic compression or because their disease is erroneously considered untreatable. The aim of this study was to evaluate the clinical data of dogs with intra-pelvic benign or well-differentiated malignant masses referred to the Torino Veterinary Teaching Hospital, and treated surgically. Clinical signs, diagnostic approach, surgical procedures and outcome were evaluated. The majority of the dogs recovered uneventfully from surgery in a couple of days, with rapid resolution of the severe preoperative clinical signs. All the dogs experienced long survival with no disease recurrence or progression, even in the well-differentiated malignant tumors. Clinical findings, especially those obtained using digital rectal and vaginal exploration are mandatory for assessing the presence of the tumor and its relationship to the other pelvic structures. Currently, in the authors’ opinion, preoperative computed tomography (CT) is also highly recommended, even if this procedure was not performed in 4 out of the 11 dogs.Dogs with benign intra-pelvic rectal or vaginal masses show symptoms indicating compression on the adjacent organs. Clinical signs usually develop late when the lesion is large enough to interfere functionally. The dogs were referred for severe fecal and/or urinary tenesmus. The data collected included signalment, clinical signs, results of physical examination, pre-surgical diagnostic tests, surgical technique used, surgical complications and histological findings. Digital rectal and vaginal examination allowed the detection of a mass occupying space in the pelvic cavity in all patients. Abdominal ultrasonography and/or total body computed tomography (CT) were used to better characterize the lesion and to exclude a metastatic spread of the tumor in case of malignancy. A dorsal approach to the rectum, a dorsal episiotomy, a midline celiotomy, and a combined perineal and abdominal approach were performed to remove the mass. No postoperative complications were observed. Benign and well-differentiated malignant mesenchymal neoplasms were histologically diagnosed. As a consequence of the chronic urethral compression caused by the mass, urinary incontinence and/or urinary retention were observed for a few postoperative days. Fecal tenesmus resolved in all cases in the immediate postoperative period. The dogs’ quality of life quickly improved after surgery, especially considering the serious and life-threatening pre-surgical clinical conditions. Both the recovery time after surgery and overall survival were also evaluated.