Multiple skeletal metastases from a penile squamous cell carcinoma in a horse

A 21‐year‐old gelding with ventral abdominal and preputial oedema was evaluated for right hindlimb lameness. Partial phallectomy had been performed 3 years prior for treatment of squamous cell carcinoma. Regional analgesia did not localise the source of lameness and nuclear scintigraphy was recommended. The results of the scan revealed severe increased radiopharmaceutical uptake in the proximal femur. Radiographic and ultrasound examinations were inconclusive. The horse was discharged with recommendations of stall confinement and a 2 week course of nonsteroidal anti‐inflammatory drugs. Four weeks later the horse presented for an inability to elevate his neck and persistent hindlimb lameness. The owner elected humane euthanasia. Post mortem examination revealed metastatic squamous cell carcinoma in the proximal femur and fifth cervical vertebrae consistent with metastasis from the penile squamous cell carcinoma. To the authors’ knowledge, multiple site bone metastasis of squamous cell carcinoma has not been reported previously in the horse.     

Squamous cell carcinoma of the vulva in a cow

An 8-year-old Holstein cow was evaluated because of a slowly enlarging vulvar mass that had impaired artificial insemination attempts. Vulvar squamous cell carcinoma was diagnosed. Clinical cases of vulvar squamous cell carcinoma have not been as widely reported as those of ocular squamous cell carcinoma in cattle. Treatment modalities for vulvar squamous cell carcinoma have not been as thoroughly investigated as for those of the ocular condition. Cryosurgery and radio-frequency hyperthermia appear to be the optimal therapeutic modalities, each providing up to 90% tumor remission.     

Survey of equine cutaneous neoplasia in the Pacific Northwest.

A retrospective study examined data regarding equine cutaneous and mucocutaneous neoplasms submitted to the Veterinary Diagnostic Laboratory at Oregon State University in a 3.5-year period. A total of 536 neoplasms were identified, accounting for 30% of the total equine pathology submissions. Sarcoid, squamous cell carcinoma, melanocytic tumors, papillomas, and mast cell tumors were the most common neoplasms, constituting 87.5% of all cutaneous neoplasms. Sarcoids represented 51.4% of all neoplasms and 15.18% of total equine accessions. Sarcoid was most common in paints, quarter horses, and Arabians, and was the only common tumor in donkeys and mules. Mean age at diagnosis of equine sarcoid was 9 years. Squamous cell carcinoma constituted 18.3% of all neoplasms and 5.41% of total equine accessions. Ocular squamous cell carcinoma was most common in paints and quarter horses, and penile/preputial squamous cell carcinoma was most common in appaloosas and quarter horses. The mean age of horses with ocular squamous cell carcinoma (13 years) and squamous cell carcinoma of the skin (15 years) was significantly less (P < 0.5) than that of horses with squamous cell carcinoma of the penis and prepuce (21 years) or vulva, anal, and perianal skin (19 years). Findings suggest that equine sarcoid and squamous cell carcinoma occur more frequently in the Pacific Northwest than in the northeastern United States.     

A case of papillary squamous cell carcinoma in the mandible of a young French bulldog

A 7-month-old castrated French bulldog was presented with a left-sided mandibular tumor. The initial tumor biopsy diagnosis was ameloblastoma. The owner brought this dog the Kitasato University Veterinary Teaching Hospital for more detailed examination and treatment. Computed tomography revealed a tumor on the left lateral mandibular gingiva from the caudal third of the incisor tooth to the right canine tooth, associated with severe amorphous osteolysis of the mandibular bone. The tumor was surgically excised and diagnosed as papillary squamous cell carcinoma. Currently, 2514 d (6.9 y) since the operation, the dog is healthy, without recurrence.Key clinical message:Although papillary squamous cell carcinoma is rare, many cases have been reported in the oral cavity of medium-to large-sized dogs. Based on this report, papillary squamous cell carcinoma can occur in small dogs such as young French bulldogs and a good prognosis can be achieved with proper resection.     

Feline papillomavirus infection in a cat with Bowen-like disease and cutaneous squamous cell carcinoma

A cutaneous mass in the neck was excised in a 13-year-old cat. Histopathological examination of the resected tissue revealed a multicentric squamous cell carcinoma in situ resembling Bowen's disease of man. The tumor showed a multifocal transformation to an infiltrative squamous cell carcinoma. Histological and immunohistological findings excluded actinic keratosis and feline viral plaques and allowed a classification as an irregular non-hyperkeratotic type of multicentric squamous cell carcinoma in situ. As a possible causative agent feline papillomavirus type 2 was detected using nested PCR in formalin-fixed material.     

Squamous cell carcinoma with sarcomatous stroma in the nasal cavity of a dog

This is a report of an unusual squamous cell carcinoma in the nasal cavity of a dog. A 13-year-old Golden Retriever was presented with a unilateral nasal and ocular discharge. Although a nasal tumour was suspected, initial diagnostic investigations were unrewarding, and, with worsening clinical signs, the dog was euthanatized. Necropsy examination confirmed the presence of a nasal tumour that was composed histologically of both a well-differentiated squamous cell carcinoma component blending with a predominant spindle cell component. Immunohistochemical staining with anti-human keratin/cytokeratin (AE1/AE3, CAM 5.2 and broad spectrum cytokeratin), Vimentin, Desmin, smooth muscle actin and S-100 protein supported a diagnosis of a squamous cell carcinoma with (pseudo) sarcomatous stroma.     

Multisite integumentary squamous cell carcinoma in an African grey parrot (Psittacus erithacus erithacus)

A 22-year-old male African grey parrot (Psittacus erithacus erithacus) had had episodes of chronic feather picking and self-mutilation for 10 years; it had a 5 cm diameter right axillary wound and a 2 cm left dorsal patagial wound. Initial treatment with azithromycin and wound management was unsuccessful. Biopsies of both masses indicated squamous cell carcinoma. The left patagial tumour was removed completely by electrocautery. Cisplatin was administered weekly into multiple sites on the right axillary tumour and it initially appeared to regress; however, the bird's condition deteriorated after a month of treatment, and it was euthanased. The tumour was confirmed postmortem to be squamous cell carcinoma, which had invaded local tissues. The aetiology of the carcinoma may have been secondary to chronic focal trauma.     

Carcinoma in the urinary bladder of a cat: cytologic findings and a review of the literature

Percutaneous fine needle aspiration biopsy (FNAB) was used to diagnose a urinary bladder carcinoma in an aged cat. The cytologic appearance of specimens collected initially was similar to that reported for canine transitional cell carcinoma. However, impression smears of the tumor made at necropsy 7 weeks later consisted predominantly of atypical squamous epithelial cells compatible with squamous cell carcinoma. Histologically, the malignancy was noted to have intermixed areas of abnormal squamous and transitional cell proliferation. The neoplasia was interpreted as a transitional cell carcinoma with extensive transformation to squamous cell carcinoma. This report examines the use and limitations of FNAB in the diagnosis of feline urinary bladder carcinoma and the incidence and behavior of these tumors in the cat.     

Photodynamic therapy as a treatment for esophageal squamous cell carcinoma in a dog

Intrathoracic esophageal squamous cell carcinoma was diagnosed by endoscopy in an 11-year-old, castrated male Labrador retriever with signs of regurgitation and weight loss. Photodynamic therapy with photofrin was administered three times under endoscopic guidance over a two-month period. A partial response to photodynamic therapy was supported by a reduction in tumor size (noted on serial endoscopic examinations) and by a return to oral alimentation. The dog was euthanized due to recurrent regurgitation and aspiration pneumonia nine months after the onset of therapy. Necropsy revealed marked local invasiveness and regional lymph node metastasis of the esophageal squamous cell carcinoma in addition to pneumonia. The application of photodynamic therapy in the treatment of canine esophageal squamous cell carcinoma is discussed and compared with the human literature.     

Squamous cell carcinoma of the corneoscleral limbus in a dog.

Squamous cell carcinoma is an uncommon tumor of the cornea in dogs. A 12-year-old Shih Tzu with a history of chronic keratoconjunctivitis sicca was diagnosed as having squamous cell carcinoma of the corneoscleral limbus. The lesion was treated by surgical resection and cryotherapy. One year after surgery, multiple tumors, apparently unrelated to the first tumor, appeared on the same cornea. Keratoconjunctivitis sicca may have predisposed the dog to corneal squamous cell carcinoma development.     

Squamous cell carcinoma of the vagina and cervix in sheep - case report

This report describes the clinical and histopathological characteristics of a squamous cell carcinoma infiltrating the cervix and the vaginal wall, producing reproductive symptoms and subnormal fertility in an adult ewe. Necropsy showed a large (15-cm-long) neoplastic mass infiltrating the vaginal wall and the cervix. Histopathological examination revealed atypical squamous epithelial cords invading the basal membrane and dermis, round anaplastic cells, focal areas of necrosis, keratinisation of isolated cells, and pronounced infiltration by mononuclear cells around the cords. No squamous cell carcinoma of such localisation has been reported from sheep before. In humans, this tumour is the most common gynaecological malignancy in the world.     

Squamous cell carcinoma originating from a cutaneous scar in a llama.

A nonhealing wound associated with a laceration in a 12-year-old llama was evaluated. Initial attempts at closure were unsuccessful and biopsy revealed scar tissue. Subsequent biopsies, 18 mo later, revealed squamous cell carcinoma with regional metastasis. This report describes squamous cell carcinoma, secondary to a traumatic wound in a llama.     

Presence of p53 mutations in feline neoplasms

A region from exon 4 to 8 of the tumour suppressor gene p53 was analysed in 60 feline tumours (30 fibrosarcomas, seven malignant histiocytomas, three lymphosarcomas, five basal cell tumours, five squamous cell carcinomas, two adenocarcinomas of tubular skin glands, one undifferentiated carcinoma of the skin, seven mammary carcinomas). Missense mutations were detected in two fibrosarcomas, one malignant fibrous histiocytoma, the undifferentiated carcinoma of the skin and one mammary carcinoma. One nonsense mutation was detected in one fibrosarcoma and one deletion/frameshift-mutation was observed in one squamous cell carcinoma.     

Use of the neodymium:yttrium-aluminum-garnet laser for treatment of squamous cell carcinoma of the nasal planum in a cat.

A mature castrated male domestic shorthair cat was referred for treatment of an excoriated, ulcerated area on the nasal planum. Undifferentiated squamous cell carcinoma was diagnosed. Surgical resection of the nasal planum was not an option, so the lesion was treated 4 times with neodymium:yttrium-aluminum-garnet laser. Laser surgery results in uniform photovaporization of large volumes of tissue. Although treatment with laser does not yield tissue specimens suitable for histologic evaluation, it can result in a cosmetically suitable appearance and can extend the predicted life span. A diagnosis of undifferentiated squamous cell carcinoma has a guarded prognosis: however, the cat of this report survived more than 18 months.     

Cutaneous squamous cell carcinoma in an African pygmy hedgehog (Atelerix albiventris)

A cutaneous mass was surgically excised in a 4-year-old African pygmy hedgehog (Atelerix albiventris). A squamous cell carcinoma was diagnosed based on histopathological examination and local recurrence following excision is strongly suspected. To the authors’ knowledge, this is the first well-documented report of a cutaneous squamous cell carcinoma in this species.     

Surgical resection of a squamous cell carcinoma in the perianal region of a 25-year-old crossbred American Paint gelding using sharp surgical excision,laser excision and chemotherapy

A 25 year-old American Paint gelding was referred to the Onderstepoort Academic Veterinary Hospital with an ulcerated lesion of nonpigmented skin at the right lateral aspect of the perianal region. An infiltrating squamous cell carcinoma was suspected. Surgical excision and ablation with sharp surgical excision and a diode laser was performed although complete excision was not possible due to the tumour location. Intralesional chemotherapy was performed at the completion of the surgical excision and continued in the post-operative period. Histological examination of the excised lesion confirmed a diagnosis of squamous cell carcinoma and revealed incomplete resection margins at the medial, dorsal and ventral aspects of the surgical site. The surgical site healed uneventfully and a re-examination at 6 months post-surgery revealed the gelding to have normal clinical parameters with no perianal lesions.     

Sublingual squamous cell carcinoma in an Atlantic bottlenose dolphin (Tursiops truncatus).

A 22-yr-old captive-born Atlantic bottlenose dolphin (Tursiops truncatus) presented with a nonhealing sublingual mucosal ulcer that was diagnosed histologically as a squamous cell carcinoma, the first such report in a dolphin. The lesion was excised completely and has not recurred.     

Squamous cell carcinoma of the anal sacs in three dogs

Anal sac squamous cell carcinoma is rare in dogs. Five cases have been previously reported, treatment of which involved surgery alone. This report describes three further cases of canine anal sac squamous cell carcinoma which underwent medical (meloxicam) management alone, resulting in survival of up to seven months. No metastases were identified. Squamous cell carcinoma, although extremely uncommon, should be considered as a possible differential diagnosis when a dog is presented for investigation of an anal sac mass.     

Superficial keratectomy and topical mitomycin C as therapy for a corneal squamous cell carcinoma in a dog

A 10-year-old female West Highland white terrier was presented with refractory hyperplastic keratitis of the left cornea of one month's duration. At this time, a vascularised and rough lesion 5 mm in diameter was observed on the left cornea. No other abnormality was recognised on the affected eye. The corneal neoplasm was surgically removed and histologically diagnosed as a squamous cell carcinoma. For two months after the surgery, 0.04 percent mitomycin C (MMC) eye drops were applied as adjuvant chemotherapy. Primary corneal squamous cell carcinoma with no history of keratoconjunctivitis sicca is rare in dogs. In the present report, surgical removal of the neoplasm was combined with the topical administration of the anticancer drug mitomycin C and a good prognosis was obtained. The result indicates that the combination treatment used in this case may be an appropriate therapeutic choice for corneal squamous cell carcinoma in dogs.