Telangiectatic osteosarcoma in four dogs: Cytologic, histopathologic, cytochemical, and immunohistochemical findings.

Telangiectatic osteosarcoma is a rare variant of osteosarcoma histologically and clinically similar to hemangiosarcoma (HSA). This case series describes the imaging and cytologic features of four histologically confirmed telangiectatic osteosarcomas, including the use of cytochemical stains. Alkaline phosphatase (ALP) was applied to Wright-Giemsa-stained cytology slides, and Factor VIII immunohistochemistry was evaluated. Cytologic characteristics included atypical mesenchymal cells with evidence of acute and chronic hemorrhage. Telangiectatic osteosarcoma cases had positive ALP cytochemical staining, while control HSA cases were negative. Factor VIII immunohistochemistry was negative in telangiectatic osteosarcoma and positive in HSA. Cytologic diagnosis of telangiectatic osteosarcoma with positive ALP cytochemical staining can help differentiate this neoplasm from HSA.

Successful surgical correction of caudal duplication syndrome in a dog.

OBJECTIVE: To describe a case of caudal duplication successfully operated with long-term follow-up. ANIMAL: A 12-week-old female Chihuahua mix. CLINICAL PRESENTATION, PROGRESSION, AND PROCEDURES: The dog of this report presented for evaluation of duplicate external organs, including 2 anuses, 2 vulvas, and 2 tails. The dog was clinically normal except for signs of cystitis. Contrast CT identified complete urogenital and anorectal duplication, characterized by duplication of the cecum, descending colon/rectum, urinary bladder, urethra, uterus, and ovaries, with left-sided rectovestibular fistula. TREATMENT AND OUTCOME: Exploratory laparotomy was performed to remove the left cecum and colon, the left ureter was transected and implanted into the right urinary bladder, the left bladder and urethra were removed, and bilateral ovariohysterectomy removed 4 ovaries and 2 uteruses. Following abdominal closure, the left anus and vulva with remaining portions of distal rectum and urethra, respectively, were removed en bloc with both tails. Long-term follow-up at 5 years showed the dog to be clinically normal. CLINICAL RELEVANCE: Caudal duplication is extremely rare in veterinary medicine, and this report details successful surgical correction with good long-term follow-up.