Surgical treatment of 45 horses affected by squamous cell carcinoma of the penis and prepuce

The medical records of 45 horses treated for suspected squamous cell carcinoma of the penis and/or prepuce were reviewed. The age of 40 horses was known, and these had a mean age of 17.4 years. The duration of neoplasia was known for only 3 of the 45 horses. The results of histological evaluation of lesions, available for 35 horses, confirmed that the diseased tissue was squamous cell carcinoma. The location of gross neoplastic lesions was recorded for 43 horses; the glans penis was involved in 24 horses, the body of the penis or the inner lamina of the preputial fold in 27 horses, and the external fold of the prepuce in 10 horses. Surgical treatments of these horses included phallectomy (penile amputation) in 35 horses, segmental posthectomy in 4 horses, phallectomy plus segmental posthectomy in 2 horses, and en bloc resection of the penis, prepuce and superficial inguinal lymph nodes with penile retroversion in 4 cases. Short-term complications in the immediate postoperative period included preputial oedema and haemorrhage at the end of urination. One horse developed acute urinary retention because of severe urethral oedema. Long-term (>1 year) follow-up information was obtained for 31 horses. Neoplasia of the penis and/or prepuce recurred in 6 of these 31 horses (19%), and in 5 of these the recurrence necessitated euthanasia of the horse.     

Penile and preputial squamous cell carcinoma in the horse: a retrospective study of treatment of 77 affected horses

Reasons for performing study: The most common penile and preputial neoplasm in the horse is the squamous cell carcinoma (SCC), but no large surveys of treatment and effects of the grade of the tumour, based on the degree of differentiation, on outcome of affected horses are available. Objectives: Analysis of treatment of male horses affected with SCC of the external genitalia and long‐term results of treatment. Methods: Seventy‐seven cases of SCC were evaluated. Data recorded included treatment, outcome, post operative histopathology and retrospective tumour grading. Results: Treatments included: cryosurgery, excision, partial phallectomy, partial phallectomy and sheath ablation, and en bloc penile and preputial resection with penile retroversion and removal of inguinal lymph nodes. The incidence of recurrence after partial phallectomy was 25.6% (10/39) and following incomplete removal was 17.9% (7/39). The incidence of recurrence after en bloc resection with retroversion was 12.5% (1/8). In horses with confirmed inguinal lymph node metastasis, the incidence of recurrence was 25.0% (1/4). Poorly differentiated SCCs were more likely to metastasise than well differentiated SCCs, and there was a greater chance that the treatment would be unsuccessful. The success of treatment, complete removal and in preventing recurrence of the tumour, of male horses with SCC of the external genitalia was 55.7%. Conclusions: Horses that receive only partial phallectomy for treatment for SCC of the external genitalia have a high incidence of recurrence in contrast to horses that receive an en bloc resection. Tumour grading of SCC can help predict prognosis and guide selection of treatment.     

Penile Amputation and Sheath Ablation in the Horse

OBJECTIVE: To report a surgical technique for penile amputation and sheath ablation in horses. Study Design-Retrospective study. Animals or Sample Population-Twenty-five adult geldings of various breeds with conditions requiring penile amputation and sheath ablation. METHODS: The medical records of horses that had penile amputation and sheath ablation were reviewed. Briefly, the technique involved en bloc resection of the skin and subcutaneous tissues of the inner and outer lamina of the prepuce and penile shaft. Resection of the penile shaft, proximal to diseased segments, and spatulation of the urethral mucosa was followed by fixation of the penis to the ventral abdomen and closure of the peripreputial skin over the ventral aspect of the penis and creation of a new mucocutaneous junction at the urethral orifice. RESULTS: Mild to moderate postoperative hemorrhage occurred in all horses. Partial dehiscence of the mucocutaneous junction occurred in 8 horses; all healed by second intention. Postoperative pain lasting 24 to 48 hours occurred in 7 horses; 1 required epidural analgesia for pain relief. Long-term follow-up was available for 8 horses; none had any long-term complications. CLINICAL RELEVANCE: Partial amputation of the penis with pexy to the ventral abdomen and revision of the peripreputial skin can be used as an alternative to en bloc resection and penile retroversion for lesions involving the free part of the penis and the prepuce. It requires smaller incisions and results in less alteration to the normal appearance of the external genitalia than retroversion techniques, while still allowing the surgeon to remove extensive portions of the penis and extirpate the regional lymph nodes.     

Preputial damage and lateral penile displacement during castration in a degu

CASE DESCRIPTION: A 2-month-old male degu was treated for preputial damage and lateral penile displacement that occurred during attempted castration. CLINICAL FINDINGS: Bruising and swelling of the prepuce and severe edema to the left of the prepuce were evident. The penis could not be extruded from the prepuce. Radiography revealed a large bladder. Contrast medium injected into the prepuce filled the peripreputial subcutaneous tissues. TREATMENT AND OUTCOME: During surgical exploration through a peripreputial approach, the penis was found to be completely separated from the prepuce and located in the adjacent subcutaneous tissue. The penis was repositioned in the prepuce and anchored with a suture at its base. The following day, the preputial orifice was crusted over, urine was leaking from the incision, and the penis could not be extruded from the prepuce. The anchoring suture was removed, and the tip of the penis was sutured to the preputial orifice so that the penis protruded slightly from the prepuce. Urination was normal after the second surgery. Two years later, the preputial orifice remained adhered to the distal portion of the penis and the exposed penile tissue was healthy. CLINICAL RELEVANCE: Penile displacement from the prepuce is an unusual complication of castration in degus. The surgical technique used in this animal may be an effective means of repair. Permanent exposure of the tip of the penis may be well-tolerated in degus.     

Genital neoplasms treated by en bloc resection and penile retroversion in horses: 10 cases (1977-1986)

The medical records of 10 horses with invasive neoplasms of the penis, prepuce, and/or superficial inguinal lymph nodes in which treatment involved en bloc resection and penile retroversion were reviewed. All were geldings and ranged in age from 12 to 25 years (mean, 19 years). Evaluation of biopsy specimens obtained before surgery confirmed lymphosarcoma in 1 horse and squamous cell carcinoma in 9 horses. Typical history included swelling, ulceration, and abscessation of the penis and prepuce and large superficial inguinal lymph nodes. Complications after surgery included dehiscence of the urethrostomy site (4 horses), dehiscence of the ventral skin incision (1 horse), urine scalding of 1 hind limb (1 horse), cystitis (1 horse), severe hemorrhage (1 horse), and diarrhea (1 horse). One horse was euthanatized during hospitalization, because of severe dehydration secondary to diarrhea. At necropsy, firm nodules were scattered in the pulmonary parenchyma, myocardium, thyroid gland, parathyroid glands, cranial mediastinum, kidneys, and hilar lymph nodes. Microscopic examination of the nodules revealed undifferentiated carcinoma. Nine horses were discharged from the hospital between 1 and 5 weeks after surgery. The mean follow-up interval was 27 months (range, 6 to 96 months). Eight horses had no evidence of recurrence. One horse had recurrence of neoplasm at 6 months and was euthanatized 12 months later.     

Application of preputial tube-flap urethroplasty to establish a neourethra in a male dog with complications after preputial urethrostomy

A 14-year-old male poodle weighing 7.5 kg presented due to complications after preputial urethrostomy for management of preprostatic urethral rupture. Revision surgery was performed with preputial tube-flap urethroplasty via preputiotomy. A longitudinal flap was raised from the prepuce and anastomosed to the end of the previously cut urethra to create a neourethra and reduce tension at the urethrostomy site. Follow-up retrograde positive contrast urethrography performed 10 days and 6 months postoperatively showed no contrast leakage from either the neourethra tube flap or new preputial urethrostomy. A follow-up email questionnaire, based on the American Urological Association Symptom Index, was completed by the owner 6 months after surgery. The dog had excellent symptom scores, and urinated from the prepuce without difficulty in a manner resembling physiological urination.     

Single stage urethroplasty for perineal hypospadias in a foal

The incidence of hypospadias is increasing in man, but the condition is rarely reported in horses. There are few available data regarding the surgical management of this disorder in horses, with no previous published report of urethral reconstructive surgery and only two reports documenting phallectomy procedures. This case report documents hypospadias repair, not previously reported in the horse, in a Thoroughbred foal with proximal hypospadias. The indication for surgery was contact dermatitis of the hind leg, which was impairing the foal's ambulation and had the potential to impair the foal's racing ability. Preoperative examination revealed a proximal hypospadias with a wide urethral plate. The anus was normal. The foal was otherwise thriving. A single stage urethroplasty was performed, during which the urethral plate was tubularised in two layers and the urethral meatus was successfully relocated distally to open upon the glans. The urethroplasty was covered with dartos fascia and the penile shaft skin and prepuce were reconstructed. Minor superficial dehiscence of the wound was successfully managed conservatively. Post‐operatively, urine was voided through the opening created on the glans penis, resolving the contact dermatitis. Follow‐up after 3 years confirmed that the horse continues to void through the re‐sited meatus without complication and had gone on to race successfully. In conclusion, we present the first report of reconstructive urethroplasty for the treatment of a horse for proximal hypospadias with good functionality and long‐term outcome.     

Preputial hematoma in a stallion

An 8-year-old Quarter Horse stallion was admitted with a swelling involving the prepuce, dorsal part of the scrotum, and root of the penis. The swelling was first noticed 10 days after breeding, with no evidence that it had resulted from a kick by the mare. The penis was retracted into the prepuce, except for a 10- to 15-cm protrusion of the glans penis. Treatment included warm hydrotherapy, massage, stockinette compression, antidiuretics, antibiotics, penile support, and exercise, without success. At necropsy, a massive preputial hematoma was found extending forward from the root of the penis to 12 cm proximal to the glans penis. The exact origin of the hematoma could not be determined. Most likely, bleeding had originated from the vascular plexus lying subfascially on the surface of the penis outside the intact tunica albuginea or from a branch of the external pudendal artery.     

Surgical correction of a congenital preputial and penile deformity in a dog

An 11-month-old, intact male Great Pyrenees was presented for recurrent, nonpainful accumulation of suppurative fluid within the prepuce. Surgical exploration revealed a continuation of the urethral mucosa with the cutaneous epidermis of the prepuce, thus creating a closed preputial cavity surrounding the penis where fluid could accumulate. A persistent frenulum and a previously undescribed tissue remnant connecting the dorsal and distal aspects of the penis to the dorsal wall of the prepuce were also present. Surgical correction of the preputial and penile deformity, along with correction of the resulting paraphimosis and pendulous prepuce that became apparent following the initial surgery, are discussed.     

Priapism Secondary to Perineal Abscess in a Dog – A Case Report

A 7‐year‐old intact male Boxer was referred to our services at the Veterinary Teaching Hospital of the University of Trás‐os‐Montes and Alto Douro, suffering from a persistently erect penis (including the bulbus glandis) that had been exposed for several days. Radiographic and ultrasonographic examinations detected a 5.0 × 3.5 cm mass located dorso‐laterally to the urinary bladder. The microbial culture of the mass revealed Staphylococcus spp. At that time, we suspected the involvement of an abscess in the origin of the priapism. Medical and surgical treatments were promptly instituted, which allowed for penile withdrawal into the prepuce; however, the resolution of the penile erection was not accomplished in the following days and penile amputation was required. Histological evaluation of the excised penis revealed extensive infarction of the erectile tissue of the pars longa and bulbus glandis, and also of the blood vessels of the penis. Following penile amputation and antimicrobial therapy, the animal fully recovered. Ultimately, the animal died as a consequence of gastric torsion. At necropsy, some lesions compatible with a previous perforation of the intestinal wall were recorded. The data gathered from the anamnesis, the physical and imaging examinations, along with the post‐mortem findings, allowed us to conclude that in this clinical case the primary cause of priapism was a perineal abscess due to bowel perforation.     

Surgical treatment of phimosis due to preputial stenosis in a Thoroughbred colt

A 6-month-old Thoroughbred colt was referred to Rossdales Equine Hospital with a recent history of discomfort and inability to protrude the penis whilst urinating, resulting in accumulation of urine within the prepuce. Careful examination and manual palpation revealed a constrictive ring of fibrous tissue at the level of the preputial orifice. With no evidence of trauma or a persistent penile frenulum, a tentative diagnosis of phimosis due to congenital preputial stenosis was made. Exploratory surgery confirmed the diagnosis and surgical transection and release of the fibromuscular ring at three sites allowed the colt to protrude the penis and urinate normally immediately post-operatively. At follow-up examination 11 months later, the colt continued to be able to extrude the penis and urinate conventionally. A slight excess of skin was present at the end of the prepuce but this was only of minor cosmetic concern.     

Use of a preputial circumferential mucosal flap for hypospadias management in a Boston terrier

An eight-week-old male Boston terrier presented for penile desiccation and urine pooling in the prepuce due to congenital hypospadias. An advancement flap was created from the dorsal mucosa of the incompletely formed prepuce and sutured circumferentially to construct a longer distal preputial mucosa. V- to Y-plasty of the ventral abdominal skin was utilised to create the preputial skin overlying the mucosal flap. Urethrostomy and partial penile amputation were also performed. Following surgery, the clinical signs of penile desiccation and preputial urine pooling resolved and acceptable cosmetic appearance was achieved. This technique may be considered for glandular or penile hypospadias or following resection of the ventral aspect of the distal prepuce when inadequate tissue is present for a simple two-layer closure of the preputial mucosa and skin.     

Causes of copulatory failure in beef bulls

A cow in full standing estrus is required to assess a bull's ability to copulate. Insufficient libido is not involved if the bull sniffs the cow's vulva and attempts to mount. Blood or pus exiting the penis or prepuce indicates penile or preputial lacerations or other lesions. Rear foot or stifle lesions, seminal vesiculitis, traumatic reticulitis or lumbar spinal injuries may prevent the bull from mounting. Preputial stenosis, penile adhesions, desensitization, hematomas or deviations, peripreputial abscess, cavernosal shunts, insufficient penile length and occlusions of the cavernosal canals may prevent intromission after mounting.     

Alternative method to facilitate resolution of paraphimosis after penile trauma in the horse

Inflammation associated with traumatic injury to the penis is characterised by pain, heat and oedema. Ensuing penile swelling interferes with retraction of the penis into the prepuce, resulting in paraphimosis. This report describes the use of a 5 l capacity pressure infusion bag to reduce penile oedema in three horses. This technique provided complete resolution of oedema and associated paraphimosis in approximately 1 h. The use of the bag, along with an abdominoinguinal bandage, a plastic funnel suspensory device, or a penile repulsion device (Probang) to avoid recurrence, offers a novel treatment that may be performed with the horse sedated.     

Hypospadias in a Friesian gelding

Objective: To report clinical signs and management of hypospadias in a horse. Study Design: Clinical report. Animal: A 6‐year‐old, Friesian gelding. Methods: Partial phallectomy was performed to resolve contact dermatitis of the pelvic limbs and abnormal behavior during urination. Subsequent urethral meatal stenosis was treated by revision. Results: Hypospadias and chordee caused altered direction of urine flow, contact dermatitis of the pelvic limbs, and abnormal behavior. Partial phallectomy and subsequent revision after meatal stenosis resolved urine direction, flow and abnormal behavior. Conclusions: Abnormalities of the urinary tract associated with hypospadias can result in urine‐induced, contact dermatitis and distress during urination, but these complications can be resolved by partial phallectomy.     

Complicated urethral rupture and scrotal urethrostomy in a Bongo antelope (Tragelaphus eurycerus isaaci)

A 4-yr-old, 300-kg male Bongo antelope presented a fluctuant swelling on the ventral abdomen surrounding the penis, which was confirmed later as compatible with urethral rupture. Initial treatment included broad-spectrum antibiotic and radical surgical debridement. Total prepuce and partial penile amputation with orchidectomy was performed and normal micturition was restored. At a later stage, when the extent of the lesion was controlled, a permanent scrotal urethrostomy was performed. Complete healing by second intention was achieved 2 mo after the last surgery. Although the outcome was very good, considering the extent and severity of the tissue damage, prompt permanent urethrostomy when urethral rupture was first suspected would have prevented deterioration of the condition and prevented the need for extensive surgery.     

Arterial supply of the penis in agoutis (Dasyprocta prymnolpha, Wagler, 1831)

The arterial vascularization of agoutis’ penis (Dasyprocta prymnolopha) were analysed using ten male adults from ‘Núcleo de Estudos e Preservação de Animais Silvestres da Universidade Federal do Piauí’ (FUFPI/IBAMA n° 02/99). Among the total number of specimens, six animals had natural death and were members of the research collection of the Laboratory of Anatomy, and four were killed after anaesthesia. Stained bi‐centrifugated‐Cis‐I‐4 latex was injected in arterial vessels responsible for penis vascularization throughout the abdominal portion of aorta. The samples were fixed in 10% formaldehyde solution and arteries were dissected. The penile artery is originated as a branch of internal pudendal artery. At the level of ischiatic arch, the penile artery project two branches, the penile dorsal and the deep arteries; those arteries irrigates the penile dorsal surface and the corpus cavernosum penis. The penile dorsal arteries have an independent course up to the glans penis. Based on the conditions of this work a remarkable similarity regarding the distribution of vessels destined to the agouti penis when compared to other domestic, wild and lagomorph rodents as rabbits.     

Treatment of an osteoblastic osteosarcoma in an aged gelding

A 27‐year‐old Thoroughbred gelding was examined for a right nasal mass visible inside the right nares. Airflow through the right nostril was absent. Endoscopy and radiography revealed the mass to occupy the entire right nasal passage. Nasal biopsies were inconclusive, so en bloc resection was performed. A diagnosis of an incompletely resected osteoblastic osteosarcoma was made. Endoscopic biopsies performed 4 weeks post surgery revealed osteosarcoma cells present in the caudal right nasal cavity. Metastatic disease was not present in mandibular lymph node aspirates or on thoracic radiographs. The right nasal passage was irradiated with 12 treatments over the course of 4 weeks. Comfort and quality of life were excellent during treatment and no adverse side effects were noted. Endoscopy and follow‐up biopsies at 1, 2, 4, 12 and 14 months post radiation therapy have not found any evidence of regrowth of the osteosarcoma.     

Subtotal penile amputation and preputial urethrostomy in a dog

CASE DESCRIPTION: A 6-year-old castrated male Shih Tzu was evaluated because of intermittent bleeding during urination. CLINICAL FINDINGS: Necrosis of the cranial portion of the penile shaft extended distally from the preputial fornix. Penile necrosis secondary to strangulation from paraphimosis was diagnosed. TREATMENT AND OUTCOME: A midline preputiotomy incision was used to expose the penile shaft; amputation was performed caudal to the preputial fornix. The terminal portion of the urethra was anastomosed to the preputial mucosa, which allowed the dog to urinate through the preputial orifice. CLINICAL RELEVANCE: Unlike the more conventional urethrostomy procedures performed in dogs, preputial urethrostomy eliminates the potential for local skin irritation during urination. Preputial urethrostomy is also easier to perform in those dogs in which penile amputation is required adjacent to the preputial fornix. A release incision cranial to the prepuce can be used to facilitate caudal displacement of the preputial mucosa, which facilitates urethral anastomosis to this structure. A midline preputiotomy incision provided excellent exposure of the penile shaft for this surgical procedure.     

Combined preputial advancement and phallopexy as a revision technique for treating paraphimosis in a dog

A 7‐year‐old neutered male Jack Russell terrier‐cross was presented for signs of recurrent paraphimosis, despite previous surgical enlargement of the preputial ostium. Revision surgery was performed using a combination of preputial advancement and phallopexy, which resulted in complete and permanent coverage of the glans penis by the prepuce, and at 1 year postoperatively, no recurrence of paraphimosis had been observed. The combined techniques allow preservation of the normal penile anatomy, are relatively simple to perform and provide a cosmetic result. We recommend this combination for the treatment of paraphimosis in the dog, particularly when other techniques have failed.