Sodium iodide I 131 treatment of dogs with nonresectable thyroid tumors: 39 cases (1990-2003)

OBJECTIVE: To determine outcome for dogs with nonresectable thyroid carcinomas treated with sodium iodide I 131 and identify factors associated with outcome. DESIGN: Retrospective case series. Animals-39 dogs. PROCEDURES: A definitive or presumptive diagnosis of thyroid tumor was made on the basis of cytologic or histologic examination, abnormal accumulation of sodium pertechnetate Tc 99m during scintigraphy, or both, and dogs were treated with sodium iodide I 131. Dogs with cervical thyroid tumors were evaluated 3 to 6 weeks after 131I therapy, and residual tumor was resected when feasible. RESULTS: Prior to 131I therapy, 32 dogs had a solitary mass and 7 had metastases; 21 were hyperthyroid, 16 were euthyroid, and 2 were hypothyroid. Median survival time for dogs with local or regional tumors (ie, stage II or III) was significantly longer (839 days) than median survival time for dogs with metastasis (366 days). Tumor site (cervical vs ectopic), dose of sodium iodide I 131, age, body weight, treatment (131I therapy alone vs 131I therapy followed by surgery), and serum T4 concentration prior to 131I therapy were not significantly associated with survival time. Three dogs died of radioiodine-associated myelosuppression within 3 months after treatment, but no specific factor associated with development of toxicosis was identified. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that 131I therapy may result in prolonged survival times in dogs with nonresectable thyroid tumors, regardless of serum thyroxine concentration prior to treatment. Dogs undergoing 131I therapy should be monitored for signs of bone marrow suppression.     

Treatment by digital amputation of subungual squamous cell carcinoma in dogs: 21 cases (1987-1988)

Malignant digital tumors were diagnosed in 62 dogs during a 1-year period. Twenty-one (33.9%) of the dogs had subungual squamous cell carcinoma. Each of these dogs had involvement of single digits. Sixteen (76.2%) of the dogs with squamous cell carcinoma were large-breed dogs, and 15 (71.4%) had predominantly black coats. Labrador Retrievers (n = 5, 23.8%) and Standard Poodles (n = 3, 14.3%) were the most commonly represented purebreeds. None of the dogs had evidence of metastases prior to treatment. All 21 tumors were treated by amputation of the involved digit. Histologic evidence of neoplastic bone invasion was found in 15 of the 21 amputated digits (71.4%). Local tumor recurrences were not observed. Only 1 dog developed documented metastatic disease; this dog was euthanatized because of pulmonary metastases 5 months after surgery. At the time of this report, 9 dogs (42.9%) were alive with no evidence of disease (median, 26 months after surgery), and 11 dogs (52.4%) had died or were euthanatized (median, 20 months after surgery). The cause of death in 7 dogs was known to be unrelated to squamous cell carcinoma, and the cause of death in 4 dogs was unknown. The 1-year and 2-year survival rates were 76.2% and 42.9%, respectively.     

Prognostic factors and patterns of treatment failure in dogs with unresectable differentiated thyroid carcinomas treated with megavoltage irradiation

OBJECTIVE: To determine quality and duration of progression-free survival (PFS) time in dogs with unresectable thyroid carcinomas treated with definitive megavoltage irradiation and analyze prognostic factors of PFS and patterns of failure (local recurrence vs metastasis). DESIGN: Prospective clinical trial. ANIMALS: 25 dogs with locally advanced thyroid carcinomas and no evidence of metastasis. PROCEDURE: Dogs were treated with 48 Gy during 4 weeks on an alternate-day schedule of 4 Gy/fraction. RESULTS: Irradiation was safe and effective for treatment of large unresectable thyroid carcinomas. Progression-free survival rates were 80% at 1 year and 72% at 3 years. Time to maximum tumor size reduction ranged from 8 to 22 months. Factors affecting PFS were not found. Twenty-eight percent (7/25) of dogs developed metastasis. Dogs with bilateral tumors had 16 times the risk of developing metastases, compared with dogs with a single tumor. Dogs with no evidence of tumor progression had 15 times less risk of developing metastases. Radiation-induced hypothyroidism was suspected in 2 dogs 13 and 29 months after irradiation. CONCLUSIONS AND CLINICAL RELEVANCE: Irradiation is effective for local control of thyroid tumors, despite their slow regression rate. Results provided evidence that local tumor control affects metastatic outcome in dogs with thyroid carcinomas and is a strong basis for the development of new approaches that include irradiation in the management of dogs with advanced thyroid carcinomas. Improvements in local tumor control alone may be insufficient to improve survival times because of the high risk of metastatic spread before an initial diagnosis is made, which warrants initiation of early systemic treatment.     

Hemimaxillectomy for the treatment of oral tumors in 69 dogs.

Hemimaxillectomy was performed in 69 dogs for the treatment of benign or malignant maxillary tumors. Eighteen dogs with ameloblastomas had a median disease-free interval of 21.5 months (range, 1 to 76 months), with a 72% 1-year survival time. There was recurrence in three dogs, with metastasis after malignant transformation in one of them. Based on calculated survival curves, seven dogs with squamous cell carcinoma had a median survival time of 19.2 months (range, 2 to 24 months), with a 57% 1-year survival time. There was local recurrence in two dogs. Twenty-three dogs with melanoma had a median survival time of 9.1 months (range, 1 to 46 months), and a 27% 1-year survival time. Twelve dogs died or were euthanatized because of recurrence or metastases. Fifteen dogs with fibrosarcoma had a median survival time of 12.2 months. Eight dogs died or were euthanatized because of recurrence or metastases. Six dogs with osteosarcoma had a median survival time of 4.6 months (range, 1 to 12.5 months), with a 17% 1-year survival time. Five dogs died or were euthanatized for recurrence or metastases. Tumor size or location and type of partial maxillectomy performed did not affect survival.     

Results of Partial Mandibulectomy for the Treatment of Oral Tumors in 142 Dogs

Partial mandibulectomy was performed for the treatment of benign or malignant oral tumors in 142 dogs. Forty-two dogs with a benign tumor (ameloblastoma) had a 22.5 month (range, 6 to 74 months) median disease-free interval, with a 97% 1-year survival rate; there was local recurrence in one dog. Twenty-four dogs with squamous cell carcinoma had a disease-free interval of 26 months (range, 6 to 84 months), with a 91% 1-year survival rate; recurrence and metastasis developed in two dogs and metastatic disease in one dog. Based on survival curves, 37 dogs with a melanoma had a median survival time of 9.9 months (range, 1 to 36 months), with a 21% 1-year survival rate; 20 dogs died or were euthanatized for recurrent or metastatic disease. Twenty dogs with osteosarcoma had a median survival time of 13.6 months (range, 3 to 28 months), with a 35% 1-year survival rate; nine dogs died or were euthanatized for recurrent or metastatic disease. Nineteen dogs with fibrosarcoma had median survival time of 10.6 months (range, 3 to 32 months), with a 50% 1-year survival rate; 12 dogs died or were euthanatized for recurrent or metastatic disease. Results of this and previous studies demonstrated that partial mandibulectomy was effective in prolonging survival and decreasing recurrence for squamous cell carcinoma and ameloblastoma. Progressive disease and corresponding low survival times were common in dogs with melanoma, osteosarcoma, and fibrosarcoma. There were no differences in survival times or the progression of disease among five partial hemimandibulectomy procedures. The high rates of recurrence and metastasis in dogs with these tumors suggest a need for evaluation of ancillary chemotherapy and local radiation therapy to decrease the prevalence of progressive disease.     

Carotid Body Tumors in the Dog Eleven Cases (1978–1988)

Case records of 11 dogs with histologically confirmed carotid body tumors were reviewed. Surgical excision had been attempted in ten dogs with carotid body tumors, and one dog had been euthanatized at diagnosis. There were no intraoperative deaths but perioperative mortality was 40%. Horner's syndrome and laryngeal paralysis were the most common postoperative morbidities. The median survival time after surgery alone in the four dogs that survived the perioperative period was 25.5 months (range, 12-45 months). Two dogs treated with postoperative radiation therapy had survival times of 6 and 27 months. Of the six dogs surviving the perioperative period, two dogs are still alive at 19 and 32 months postoperatively. Of the four dogs that died, one was euthanatized 12 months postoperatively for nontumor-related causes. The remaining three dogs died of distant metastases. The carotid body tumors studied were characterized by local tissue invasion, neurovascular complications after therapy, and a propensity to metastasize to multiple sites in the body.     

Efficacy of radiation therapy for incompletely resected grade-III mast cell tumors in dogs: 31 cases (1987-1998)

OBJECTIVE: To determine the efficacy (durations of remission and survival) of an alternating-day radiation protocol for incompletely excised histologic grade-III solitary mast cell tumors (MCTs) in dogs. DESIGN: Retrospective study. ANIMALS: 31 dogs. PROCEDURE: Radiation (52 Gy in an 18-fraction alternating-day protocol) was delivered to an area bordered by margins > or = 3 cm around the surgical scar and to the associated local-regional lymph nodes. Dogs were not given chemotherapeutic agents concurrently or after radiation. Information on signalment, duration of remission, and survival time was obtained from medical records. RESULTS: Median and mean durations of remission were 27.7 and 17.0 months, respectively (range, 1 to 47 months). Median and mean durations of survival were 28 and 20 months, respectively (range, 3 to 52 months). Dogs with tumors located on the skin of the pinna, perineum, and prepuce had a median duration of remission greater than dogs with tumors located at other sites (27.7 and 14.4 months, respectively). Dogs with tumors < or = 3 cm in maximum diameter before surgery survived longer than dogs with tumors > 3 cm (31 and 24 months, respectively). The remission rate was 65% and survival rate was 71% at 1 year after treatment. Sixteen dogs that were euthanatized had complications associated with local-regional tumor progression. Systemic metastases to liver, spleen, intestine, and bone marrow were detected in 1 dog. CONCLUSIONS AND CLINICAL RELEVANCE: Without further treatment, incompletely excised grade-III mast cell tumors have high local-regional recurrence; local-regional treatment with radiation may effectively be used to manage many such tumors.     

En Bloc Resection of Primary Rib Tumors in 40 Dogs

Single or multiple rib resection was performed in 40 dogs for the treatment of primary osteosarcoma or chondrosarcoma. The resulting thoracic wall defect was closed with polypropylene (12 dogs), primary muscle flap (16 dogs), diaphragmatic advancement (10 dogs), or a combination (2 dogs). Few immediate (less than 2 weeks) postoperative complications were observed. Twenty dogs with osteosarcoma had a median survival time of 3.3 months (range, 0.5 to 23 months), with a 20% 6-month survival time. Metastases occurred in all the dogs. Fourteen dogs with chondrosarcoma followed up longer than 2 weeks had a median survival time of 10.7 months (range, 0.5 to 36 months) with a 64% 6-month survival time. Eight dogs developed metastases, five died from concurrent disease, and one dog is alive. Dogs with chondrosarcoma survived significantly longer than dogs with osteosarcoma. Survival time was not related to tumor size or number of ribs resected.     

Carcinoma of the apocrine glands of the anal sac in dogs: 113 cases (1985-1995)

OBJECTIVE: To characterize the signalment, clinical signs, biological behavior, and response to treatment of carcinoma of the apocrine glands of the anal sac in dogs. DESIGN: Retrospective study. ANIMALS: 113 dogs with histologically confirmed carcinoma of the apocrine glands of the anal sac. PROCEDURE: Data on signalment, clinical signs, and staging were reviewed and analyzed along with treatment modality for potential association with survival time. RESULTS: Sex distribution was approximately equal (54% female, 46% male). One hundred four dogs underwent treatment consisting of surgery, radiation therapy, chemotherapy, or multimodal treatment. Median survival for treated dogs was 544 days (range, 0 to 1,873 days). Dogs treated with chemotherapy alone had significantly shorter survival (median, 212 days) than those receiving other treatments (median, 584 days). Dogs not treated with surgery had significantly shorter survival (median, 402 days) than those that underwent surgery as part of their treatment (median, 548 days). Dogs with tumors > or = 10 cm2 had significantly shorter survival (median, 292 days) than dogs with tumors < 10 cm2 (median, 584 days). Hypercalcemia was identified in 27% (n = 29) of dogs, and those dogs had significantly shorter survival (median, 256 days), compared with those that were normocalcemic (median, 584 days). Dogs with pulmonary metastasis had significantly shorter survival (median, 219 days) than dogs without evidence of pulmonary metastasis (median, 548 days). CONCLUSIONS AND CLINICAL RELEVANCE: Unlike most previous reports, this study revealed an approximately equal sex distribution, and results suggest a more favorable prognosis.     

CT AND MRI FEATURES OF CAROTID BODY PARAGANGLIOMAS IN 16 DOGS

Carotid body tumors (paragangliomas) arise from chemoreceptors located at the carotid bifurcation. In imaging studies, this neoplasm may be confused with other neck neoplasms such as thyroid carcinoma. The purpose of this retrospective, cross‐sectional study was to describe computed tomographic (CT) and magnetic resonance imaging (MRI) characteristics of confirmed carotid body tumors in a multi‐institutional sample of dogs. A total of 16 dogs met inclusion criteria (14 examined using CT and two with MRI). The most common reason for imaging was a palpable cervical mass or respiratory signs (i.e., dyspnea or increased respiratory noises). The most commonly affected breed was Boston terrier (n = 5). Dogs were predominantly male castrated (n = 10) and the median age was 9 years [range 3–14.5]. Most tumors appeared as a large mass centered at the carotid bifurcation, with poor margination in six dogs and discrete margins in ten dogs. Masses were iso‐ to hypoattenuating to adjacent muscles in CT images and hyperintense to muscles in T1‐ and T2‐weighted MRI. For both CT and MRI, masses typically showed strong and heterogeneous contrast enhancement. There was invasion into the adjacent structures in 9/16 dogs. In six of these nine dogs, the basilar portion of the skull was affected. The external carotid artery was entrapped in seven dogs. There was invasion into the internal jugular vein in three dogs, and into the external jugular, maxillary, and linguo‐facial veins in one dog. Imaging characteristics helped explain some clinical presentations such as breathing difficulties, Horner's syndrome, head tilt, or facial nerve paralysis.     

Preliminary evidence for biologic activity of toceranib phosphate (Palladia(®)) in solid tumours

The purpose of this study was to provide an initial assessment of the potential biologic activity of toceranib phosphate (Palladia?, Pfizer Animal Health, Madison, NJ, USA) in select solid tumours in dogs. Cases in which toceranib was used to treat dogs with apocrine gland anal sac adenocarcinoma (AGASACA), metastatic osteosarcoma (OSA), thyroid carcinoma, head and neck carcinoma and nasal carcinoma were included. Clinical benefit (CB) was observed in 63/85 (74%) dogs including 28/32 AGASACA [8 partial response (PR), 20 stable disease (SD)], 11/23 OSAs (1 PR and 10 SD), 12/15 thyroid carcinomas (4 PR and 8 SD), 7/8 head and neck carcinomas [1 complete response (CR), 5 PR and 1 SD] and 5/7 (1 CR and 4 SD) nasal carcinomas. For dogs experiencing CB, the median dose of toceranib was 2.8 mg kg(-1) , 36/63 (58.7%) were dosed on a Monday/Wednesday/Friday basis and 47/63 (74.6%) were treated 4 months or longer. Although these data provide preliminary evidence that toceranib exhibits CB in dogs with certain solid tumours, future prospective studies are necessary to define its true activity.     

Idiopathic lymphoplasmacytic rhinitis in dogs: 37 cases (1997-2002)

OBJECTIVE: To determine clinical signs and rhinoscopic, computed tomographic, and histologic abnormalities in dogs with idiopathic lymphoplasmacytic rhinitis. DESIGN: Retrospective case series. ANIMALS: 37 dogs. PROCEDURE: Clinical information was obtained from medical records. Nasal computed tomographic images and histologic slides of biopsy specimens were reviewed. RESULTS: Dogs ranged from 1.5 to 14 years old (mean, 8 years); most (28) were large-breed dogs. Nasal discharge was unilateral in 11 of 26 (42%) dogs and bilateral in 15 of 26 (58%) dogs. In dogs with unilateral disease, duration of clinical signs ranged from 1.5 to 36 months (mean, 8.25 months; median, 2 months), and in dogs with bilateral disease, duration of signs ranged from 1.25 to 30 months (mean, 6.5 months; median, 4 months). Computed tomography (n = 33) most often revealed fluid accumulation (27/33 [82%]), turbinate destruction (23/33 [70%]), and frontal sinus opacification (14/33 [42%]). Rhinoscopy (n = 37) commonly demonstrated increased mucus and epithelial inflammation; turbinate destruction was detected in 8 of 37 (22%) dogs. Bilateral biopsy specimens from all 37 dogs were examined. Four dogs had only unilateral inflammatory changes. The remaining 33 dogs had bilateral lesions; in 20, lesions were more severe on 1 side than the other. CONCLUSIONS AND CLINICAL RELEVANCE: Findings suggest that idiopathic lymphoplasmacytic rhinitis is a key contributor to chronic nasal disease in dogs and may be more common than previously believed. In addition, findings suggest that idiopathic lymphoplasmacytic rhinitis is most often a bilateral disease, even among dogs with unilateral nasal discharge.     

Radioiodide (131I) therapy for the treatment of canine thyroid carcinoma

OBJECTIVE: To assess the efficacy of radioactive iodine treatment (131I) for canine thyroid carcinoma, as both the sole therapeutic modality and as an adjunct to surgery. DESIGN: Retrospective analysis of case records from the Gladesville Veterinary Hospital Nuclear Medicine Service, Sydney, between August 1988 and December 2001. CASE DETAILS: The records of 65 dogs with thyroid carcinoma were analysed according to therapy and outcome. Forty-three dogs received radioiodide therapy, either as the sole therapeutic modality (32) or as an adjunct to surgery (11). Radioisotope therapy consisted of one to three doses of 131I with a dose range of 555 to 1850 MBq. For analysis, dogs were divided into groups according to therapy: no treatment, surgery alone, surgery with radioiodide therapy or radioiodide therapy alone. Mode of therapy, dosage of 131I, clinical staging and age were all independently analysed according to survival to compare efficacy or predictive value respectively. RESULTS: When radioiodide therapy was used as an adjunct to surgery, median survival was 34 months. Censored median survival time for dogs that received radioiodide alone was 30 months. Dogs that did not receive treatment had a median survival of only 3 months. Log rank statistical analysis indicated that mode of therapy was significantly correlated with survival but that clinical stage of disease was not. CONCLUSION: The authors conclude that 131I therapy is effective at extending survival time, both as a sole therapeutic modality and as an adjunct to surgery, in dogs with invasive canine thyroid carcinoma. Incomplete surgical resection may not prolong survival in dogs also receiving 131I therapy, however surgical resection with curative intent should be recommended as the first line of therapy for mobile thyroid carcinomas. Radioisotope therapy can be recommended for cases where surgery alone is considered unlikely to be curative because of metastatic disease or local invasion, or for cases where surgery has been attempted but complete surgical removal has not been achieved.     

Inflammatory mammary carcinoma in dogs: 33 cases (1995-1999).

OBJECTIVE: To determine epidemiologic, clinical, and pathologic characteristics of inflammatory mammary carcinoma (IC) in dogs. DESIGN: Retrospective study. ANIMALS: 33 dogs with IC and 153 dogs with malignant mammary tumors other than IC. PROCEDURES: Medical records were reviewed, and signalment, history, physical examination findings, and results of thoracic radiography and necropsy were obtained. RESULTS: 33 of 436 (7.6%) dogs examined at a veterinary teaching hospital because of dysplasia or tumors of the mammary glands and 33 of 186 (17.7%) dogs with at least 1 malignant tumor had IC. Thirty-two of the 33 dogs were sexually intact. Dogs with IC were significantly older than were dogs with other malignant mammary tumors, and in dogs with IC, the tumor was initially noticed a mean of 52 days after the beginning of the last observed estrus, whereas in dogs with other mammary tumors, the tumor was initially noticed a mean of 137 days after the beginning of the last observed estrus. Dogs with IC were more likely to be anorectic and to have generalized weakness, weight loss, and thoracic metastases. Dogs with IC survived a mean of 25 days with palliative treatment. Histologically, involvement of dermal lymphatic vessels was identified in 14 of 19 (74%) dogs with IC. Two clinical forms of IC (primary and secondary) were identified. Dogs with primary IC had a worse clinical condition. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that IC is an uncommon but distinct entity in dogs. A histologic finding of dermal lymphatic involvement should be considered a hallmark for the pathologic diagnosis of IC in dogs.     

Surgical therapy of canine nasal tumors: A retrospective study (1982-1986)

The results of surgical therapy in 15 dogs with histologically confirmed nasal tumors were analyzed retrospectively and compared to previous reports. Median survival time for all dogs was seven months. When adjusted for nontumor-related deaths, median survival increased to nine months. These values are two to three times longer than previous reports. To determine possible prognostic indicators, tumor stage, location, and histological type were compared to survival time. Dogs with unilateral nasal tumors had a median survival of 11 months, as compared to three months for dogs with bilateral tumors (p = 0.005). Tumor stage and histological type were not significant factors in comparing survival times.     

Combined Gemcitabine and Carboplatin Therapy for Carcinomas in Dogs

Background: Response and adverse reactions to combined gemcitabine (GEM) and carboplatin (CARBO) therapy in dogs with carcinomas are not documented.
Hypothesis: GEM and CARBO are safe for the treatment of dogs with carcinomas.
Animals: Thirty-seven dogs with histologically or cytologically confirmed carcinomas.
Methods: Prospective clinical trial. Dogs were treated with GEM (2 mg/kg, 20–30-minute infusion IV) on Days 1 and 8 and 4 hours later, CARBO (10 mg/kg IV) on Day 1. The cycle was repeated on Day 22.
Results: Thirty-seven dogs (29 with measurable tumor) received a median of 2 cycles (range 0.5–6) for a total of 101 cycles administered. Twelve dogs (32%) developed neutropenia (3 Grade 3, and 5 Grade 4) and 9 (24%) thrombocytopenia (2 Grade 3, and 1 Grade 4). Dogs >20 kg were twice as likely to develop thrombocytopenia ( P = .023). Twenty-seven dogs (73%) had evidence of gastrointestinal (GI) toxicosis, but most signs were of mild to moderate severity and self-limiting. One dog died of treatment-related complications. Overall tumor response rate was 13%. One dog with metastatic prostatic carcinoma achieved a complete remission and 1 dog with intestinal adenocarcinoma and 1 with tonsillar squamous cell carcinoma achieved partial remission. Twelve dogs achieved stable disease for a median of 72 days.
Conclusion and Clinical Importance: GEM and CARBO combination causes mild to moderate hematologic and GI toxicosis in dogs with carcinoma. Response rate in this study was modest, and optimization of dosing of this combination is required.     

Acute Oropharyngeal and Esophageal Stick Injury in Forty‐One Dogs

Objective— To report clinical findings, treatment, and outcome in dogs with acute (<7 days) oropharyngeal or esophageal stick injury. Study Design— Retrospective study. Animals— Dogs (n=41) with acute oropharyngeal or esophageal injury. Methods— Dogs had clinical and radiographic examination, and frequently, cervical surgical exploration. The decision to operate was based on radiographic findings of cervical emphysema. Outcome was determined by owner or veterinarian interview. Results— Of 41 dogs, 27 had oropharyngeal injury and 14 had esophageal injury. Five dogs with esophageal injury died. All dogs with radiographic evidence of cervical emphysema (n=34) had ventral median cervical exploration or necropsy; 11 had wood fragment(s) retrieved. In 7 dogs without radiographic signs of cervical emphysema, wounds involving the pharynx or soft palate were treated by local debridement and lavage using an oral approach. Mean follow‐up time was 36.4 months. All wounds healed without complication; however, 1 dog that was not surgically explored had a piece of wood surgically retrieved 3 months later. Conclusions— Radiographic evidence of cervical emphysema is a frequent finding in dogs with acute penetrating oropharyngeal or esophageal injury and indicates trauma to the deeper cervical tissues. Acute penetrating injury of the oropharyngeal region, when treated appropriately, has a better prognosis than acute esophageal penetration. Clinical Relevance— Ventral median cervical surgical exploration is recommended in dogs with acute penetrating injury of the oropharynx or esophagus if there is radiographic evidence of tissue emphysema.     

Distraction–Fusion for Caudal Cervical Spondylomyelopathy Using an Intervertebral Cage and Locking Plates in 14 Dogs

Objective: To evaluate clinical and radiographic outcome in dogs with caudal cervical spondylomyelopathy (CCSM) treated with an intervertebral fusion cage and locking plates. Study Design: Prospective clinical study. Animals: Large breed dogs (n=14) with CCSM. Methods: Dogs had single level cervical spine distraction/fusion performed using an intervertebral cage with a hollow center filled with cancellous autograft and 2 ventrally applied locking plates. Outcome was measured using neurologic scores and radiographic interpretation 6 weeks, 6 months, and 12 months postoperatively. Results: The surgical procedure was well tolerated in all dogs. Final outcome at 12 months was available in 9 dogs. Five dogs were judged excellent, 1 dog was good, 2 dogs were satisfactory, and 2 dogs were poor because of adjacent segment disease. Four dogs died for reasons unrelated to the procedure. Radiographically, implants remained stable over the entire follow‐up period. The disc space continued to fill with an immature pattern of new bone, which showed progressive increase in opacity and quantity. Subsidence of the cage (median 2 mm) was detected in 9 dogs at 6 weeks and remained unchanged in those that could be followed further. Conclusion: Distraction–fusion of single level CCSM in dogs with a combination of intervertebral cage and ventral locking plates is clinically effective and results in successful bony fusion.