Surgical decompression,with or without adjunctive therapy,for palliative treatment of primary vertebral osteosarcoma in dogs

Vertebral osteosarcoma (OSA) is the most common primary vertebral tumor in dogs, however studies examining the survival time after surgical decompression of these tumors are limited. There is also limited information regarding the benefit of adjunctive treatments such as radiation therapy or chemotherapy in these patients. The goal of this study was to determine survival time of dogs with primary vertebral OSA after palliative decompressive surgery alone and combined with radiation therapy and/or chemotherapy. Records from 22 client‐owned dogs diagnosed with primary vertebral OSA and treated with decompressive surgery were collected retrospectively from eight referral institutions. Survival time was assessed for dogs treated with surgery alone as well as dogs who received adjunctive radiation therapy and/or chemotherapy. Median survival time in the 12 dogs treated with surgery alone was 42 days (range: 3‐1333 days). The three dogs treated with surgery and chemotherapy had a median survival time of 82 days (range: 56‐305 days). Only one dog was treated with surgery and radiation therapy; this dog survived 101 days. Six dogs were treated with surgery, radiation therapy and chemotherapy; these dogs had a median survival time of 261 days (range: 223‐653 days). Cause of death in all cases that survived the initial postoperative period was euthanasia secondary to confirmed or suspected tumor regrowth. The results of this study suggest that definitive radiation therapy, possibly combined with concurrent chemotherapy, significantly improves survival in dogs treated with palliative decompressive surgery for vertebral OSA and should be the treatment of choice in selected cases.     

Survival in Dogs with Nasal Adenocarcinoma: 64 Cases (1981–1995)

Case records of 64 dogs with nasal adenocarcinoma were reviewed. The effects of age, gender, tumor stage, presence of metastatic lesions, and treatment method on survival time were examined. Surgery groups included rhinotomy (n = 9), transnasal curettage (n = 29), and no surgery (n = 26). Chemotherapy groups included fluorouracil-cyclophosphamide combination therapy (n = 15), mitoxantrone (n = 7), and no chemotherapy (n = 42). Fifty-three dogs received fractionated cobalt 60 radiation therapy. Surgical procedure, chemotherapy group, and stage of primary tumor were not significantly associated with survival time ( P > .05). Dogs that received radiation therapy had a significantly longer median survival time (424 days) than dogs that did not (126 days) ( P = .0001). The presence of either regional lymph node or pulmonary metastasis was associated with significantly shorter median survival time (109 days) when compared to dogs without metastases (393 days) ( P = .0125). When only dogs that had received radiation therapy were considered, neither surgical treatment nor chemotherapy group was associated with significant changes in median survival time. An alternate staging system emphasizing the presence or absence of metastases is proposed. Key words: Chemotherapy; Metastasis; Radiotherapy.     

Retrospective analysis of axial skeleton osteosarcoma in 22 large-breed dogs

Medical-records of 22 large-breed dogs (>15 kg) with osteosarcoma (OSA) of the axial skeleton were reviewed to determine prevalence of metastasis and survival associated with this neoplasm. All dogs were treated with more than 1 mode of therapy including palliative radiation (n = 12), definitive radiation (n = 8), surgery (n = 7), chemotherapy (n = 12), or some combination of these therapies. Metastasis was documented in 10 of 22 dogs (46%), and the median survival for all dogs was 137 days. Primary cause of death was local tumor recurrence (54%). Breed (retriever versus purebred versus mixed-breed survival was 100, 182, and 264 days, respectively) and radiation therapy protocol (survival in dogs treated with palliative radiation therapy versus those treated with definitive radiation therapy was 79 and 265 days, respectively) were significantly related to survival (P < .05). Prevalence of metastasis and median survival for large-breed dogs with axial skeleton OSA seems to be similar to that reported for large-breed dogs with appendicular skeleton OSA. Definitive radiation therapy may have a role in the treatment of axial skeleton osteosarcoma.     

Clinical outcomes of 30 cases (1997-2004) of canine gastrointestinal lymphoma

In 30 cases of canine gastrointestinal lymphoma, each case was localized to the stomach, small intestine, large intestine, or two or more sites. Treatments consisted of surgery alone (n=4), surgery with chemotherapy (n=8), chemotherapy alone (n=15), or supportive care (n=3). Four dogs died, 24 were euthanized, and two are currently alive. Median survival time for all cases was 13 days. In both surviving dogs, the site of lymphoma was the large intestine. Canine gastrointestinal lymphoma is a severe disease that warrants a poor to grave prognosis. However, cases of colorectal origin may have longer survival times.     

Treatment of dogs with oral melanoma by hypofractionated radiation therapy and platinum-based chemotherapy (1987-1997)

This retrospective study in 39 dogs with incompletely resected oral melanoma examined the efficacy of hypofractionated radiation therapy and platinum-containing chemotherapy. All dogs were completely staged, with the majority of dogs classified as stage 1. Dogs received 6 weekly fractions of 6-gray (Gy) megavoltage irradiation with a cobalt-60 unit or a 4-MeV (megaelectron volts) linear accelerator. Dogs received cisplatin (10-30 mg/m2 IV) or carboplatin (90 mg/m2 IV) chemotherapy 60 minutes before radiation delivery. Durations of local control, metastasis-free survival time, and overall survival time were recorded. By the Kaplan-Meier method, 15% of the dogs had local recurrence within a median time of 139 days. Fifty-one percent of the dogs developed metastatic disease within a median time of 311 days (range, 24-2, 163 days). Median survival time for all 39 dogs was 363 days. The combined use of chemotherapy and radiation therapy in this protocol provided local control consistent with previous studies. Low-dose chemotherapy was used with the intent of enhancing radiation therapy for the local control of an incompletely excised tumor. Survival times were longer than previously reported for dogs with oral malignant melanoma. Additional studies are required to determine whether these results were due to the effects of chemotherapy on microscopic disease or the enhanced local control provided by chemoradiation therapy.     

Canine intranasal tumours treated with alternating carboplatin and doxorubin in conjunction with oral piroxicam: 29 cases

Few veterinary studies have evaluated the response to chemotherapy treatment of canine intranasal tumours, while many have focused on the efficacy of radiation therapy. Given the higher costs and limited access to radiation therapy, alternative treatment options are needed. The study describes a cohort of dogs with histologically confirmed intranasal tumours treated with chemotherapy as a sole therapy. This retrospective study was conducted using data from the Melbourne Veterinary Specialist Centre (MVSC) database between 2004 and 2017. Dogs with a histologically confirmed intranasal tumour who received chemotherapy treatment were included. Signalment, presenting signs, tumour type, chemotherapy details, adverse events (AEs) and survival times were reviewed. Twenty‐nine dogs met the inclusion criteria. Overall median survival time for dogs in the study was 234 days (range 12‐1698 days). Median survival for dogs with adenocarcinoma or carcinoma (n = 12) was 280 days, transitional cell carcinoma (n = 6) 163 days, squamous cell carcinoma, anaplastic carcinoma or undifferentiated carcinoma (n = 7) 59 days and all sarcomas (n = 4) 448 days. Adverse events were reported following 28% of treatments and 69% of dogs experienced at least one AE. Twenty four per cent of all dogs experienced grade 3 or 4 toxicities. The chemotherapy protocol was generally well tolerated. The study suggests potential benefit in the use of chemotherapy for dogs with adenocarcinoma, carcinoma and sarcoma.     

Results of ligation of patent ductus arteriosus in dogs: 201 cases (1969-1988)

Surgical treatment of 201 dogs with patent ductus arteriosus at the College of Veterinary Medicine, The Ohio State University was evaluated retrospectively to determine risk factors for development of surgical complications. During surgery, 15 dogs (7%) died because of hemorrhage associated with ductus dissection (n = 8), pulmonary edema (n = 4), ventricular fibrillation (n = 1), hemorrhage not associated with ductus dissection (n = 1), and cardiac arrest immediately after ductus ligation (n = 1). An additional 8 dogs (4%) died less than 1 month after surgery (total mortality before, during, and immediately after surgery, 11%). Nineteen dogs (9.5%) developed hemorrhage during surgery. Sixteen dogs developed complications other than hemorrhage (pulmonary edema [n = 4], cardiac arrest [n = 4], iatrogenic lung trauma [n = 3], ventricular fibrillation [n = 2], septicemia [n = 2], and recanalized ductus [n = 2]). Correlation was not found between age, sex, body weight, surgical technique (Jackson method vs standard method of dissection), or surgeon level of training and development of hemorrhage during surgery, other complications, or survival less than 5 days. Positive correlation (P less than 0.05) was found between hemorrhage and death within 5 days after surgery. Positive correlation (P less than 0.05) was also found between other complications and death within 5 days after surgery. Nineteen dogs survived surgery, but later died of unrelated causes (mean life span, 57 months); 63 of the dogs were still alive and doing well as of January 1990 (mean life span, 47 months after surgery). Contrary to previous reports, age, body weight, and surgical technique did not affect results.(ABSTRACT TRUNCATED AT 250 WORDS)     

Four fraction palliative radiotherapy for osteosarcoma in 24 dogs

Twenty-four dogs underwent palliative radiotherapy consisting of four 8 gray (Gy) fractions of 60Co radiation on days 0, 7, 14, and 21 at 26 sites for axial (n=11) or appendicular (n=15) osteosarcoma. Response was noted in 92% of sites treated. Seventeen dogs were euthanized due to local or metastatic disease, one dog died of metastatic disease, five dogs died of unrelated causes, and one dog is alive. The four fraction protocol is effective for palliation of clinical signs associated with axial or appendicular osteosarcoma and may result in a higher response rate and longer survival time than three fraction palliative protocols.     

Lymphangiosarcoma in 12 dogs: a case series (1998–2013)

Lymphangiosarcoma (LAS) is an uncommon malignant neoplasia arising from lymphatic endothelium; little information exists regarding therapy. Single institutional retrospective review for canine LAS histopathology diagnoses over a 15‐year period yielded 12 dogs. Ten dogs were presented for a mass and/or swelling at cervical, trunk or limb regions. Prior to diagnosis, 10 dogs received empiric wound therapy. Cytology performed in 10 consisted of mild inflammation. Survival ranged from 60, 168 and 876 days for three dogs with palliation; 90 days with prednisone in one; 182 days with chemotherapy in one; 240, 267, 487, 630 and 941 days for five receiving surgery; and 574 days for one receiving surgery, radiation and chemotherapy. One dog is alive with recurrence at 243 days following surgery and carboplatin chemotherapy. Clinical improvement existed in LAS dogs receiving multimodal therapies. Early tissue biopsies are recommended for progressive oedematous lesions of unknown origin.     

RESULTS OF IRRADIATION OF INFILTRATIVE LIPOMA IN 13 DOGS

Thirteen dogs with infiltrative lipomas were treated with cobalt 60 radiation. Four of the thirteen dogs also received either whole body (n = 2) or combination local/whole body (n = 2) hyperthermia in conjunction with radiation therapy. Cytoreductive surgery was performed prior to radiation in 10 dogs, although only 3 dogs had microscopic disease at the time of radiation therapy. Dogs received a total dose of 45.6 Gy-63 Gy in 2.5-4 Gy/fraction on either a Monday/Wednesday/Friday schedule or on a daily Monday through Friday schedule. Twelve of the 13 dogs had computed tomography (CT) images acquired prior to irradiation. Survival time was determined from the time of completion of radiation therapy. Survival ranged from 6 months to 94 months, with a median (95% confidence interval) of 40 (18.5-77) months and a mean of 46.4 months. Only one dog was euthanized due to persistent signs related to the infiltrative lipoma at 6 months after the end of radiation therapy. There was no apparent difference in response based on whether or not the dogs received hyperthermia in conjunction with irradiation, although the numbers were too small to make any significant conclusions. It appears that dogs with infiltrative lipomas can benefit from external beam irradiation alone or in combination with surgery to effect long-term local tumor control.     

Autologous marrow transplantation as consolidation therapy for canine lymphoma: efficacy and toxicity of various regimens of total body irradiation

Dogs with malignant lymphoma were given chemotherapy consisting of nitrogen mustard, vincristine sulfate, prednisone, L-asparaginase, and 6-mercaptopurine (MOPA-6) for 14 days. Among 62 dogs that completed treatment with MOPA-6, 47 (76%) had complete remission, and 13 (21%) had partial remission and 2 had no response to chemotherapy. Twenty-two of the 62 dogs were not returned by their owners for additional therapy and died 15 to 391 (median 21) days after MOPA-6 from infections or recurrent disease. A median of 1 month after starting MOPA-6 therapy, 40 dogs (35 in complete remission, 5 in partial remission) were given total body irradiation (TBI), followed by infusion of fresh autologous marrow. Twenty dogs were given 13.5 Gray (Gy) of TBI at 4 centi-Gray (cGy)/min. Among 16 evaluable dogs, 7 had recurrence of lymphoma at a median of 169 days. Two dogs died with veno-occlusive disease of the liver, 3 with pneumonia, 3 with hemorrhage, and 1 was killed. Twenty dogs were given 11.8 to 14.7 Gy of TBI at 2 cGy/min. Among 14 evaluable dogs, 9 had recurrence of lymphoma at a median of 117 days. The remaining 5 dogs were killed at 110 to 680 days; lymphoma was not present at necropsy. The results indicated that doses of TBI of 11.8 to 14.7 Gy did not reduce the recurrence of lymphoma, compared with results obtained in a previous study with 8.4 Gy of TBI. Furthermore, increased doses of TBI increased acute and delayed toxicities. Alternatively, recurrent disease may have been due to lymphoma cells contained in the infused remission marrow.     

Histiocytic sarcomas in flat-coated retrievers: a summary of 37 cases (November 1998–March 2005)

Thirty‐seven cases of histiocytic‐like sarcomas (HLSs) in flat‐coated retriever dogs were evaluated retrospectively. This tumour accounted for 36% of the malignant tumours seen in this breed during the study period. The median age at presentation was 8.2 years. Thirty‐four dogs presented with a swelling or mass in a muscle group or surrounding a joint. The remaining three presented for rib (1), cutaneous (1) or primary splenic origin (1). A high rate of metastasis to local lymph nodes (45%), thorax (20%) and abdominal organs (20% confirmed) was seen. Overall metastastic rate by the time of death was 70%. The median survival for all dogs was 123 days. The most significant prognostic indicator was presence of distant metastasis at the time of diagnosis with median survival of 68 or 200 days, with or without metastasis, respectively. Chemotherapy and radiation therapy significantly improved survival. Dogs given chemotherapy survived a median of 185 versus 34 days for dogs that were not (P = 0.0008). Dogs treated with radiation survived a median of 182 versus 60 days for those that were not (P = 0.0282). Dogs receiving only palliative therapy survived a median of 17 versus 167 days in dogs receiving any kind of radiation, chemotherapy, surgery or combinations. A set protocol of radiation and CCNU (RTCCNU) induced minimal toxicity and provided a median survival of 208 versus 68 days for all other dogs. While this tumour carries a poor long‐term prognosis in flat‐coated retrievers, it is reasonable to treat these dogs for palliation of signs and extension of life.     

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.     

Cisplatin and doxorubicin combination chemotherapy for the treatment of canine osteosarcoma: a pilot study

Sixteen dogs with histologically confirmed appendicular osteosarcoma were treated by amputation followed by cisplatin and doxorubicin chemotherapy. All dogs began chemotherapy within 24 hours of surgery. Cisplatin was administered at 50 mg/m2 intravenously (IV) concurrent with saline-induced diuresis. Doxorubicin was administered 24 hours later at 15 mg/m2 as a slow IV bolus. This protocol was given on a 21-day cycle for 4 cycles. No dose delays were required, but dose reduction of doxorubicin was required in 2 dogs because of neutropenia. Thoracic radiography was performed every 2 months after completion of therapy to monitor for metastatic disease. Two dogs were still alive and free from disease at the time of last contact (24 and 75 months, respectively). Postmortem examinations were performed on 13 of the 14 dogs that died. Eight of these dogs were euthanized because of metastatic osteosarcoma. Of the remaining 5 dogs, euthanasia was performed because of complications of idiopathic megaesophagus (n = 1), arthritis (n = 2), and hemangiosarcoma (n = 2). The median disease-free interval and survival times were 15.7 and 18 months, respectively. When compared to a historical group of 36 dogs with appendicular osteosarcoma treated with surgery and 4 doses of cisplatin. both disease-free interval and overall survival were significantly longer in the study population (P < .015 and P < .007, respectively).     

Radiotherapy of malignant nasal tumors in 67 dogs

The nasal cavity of 67 dogs with malignant nasal neoplasia was treated with radiation. Preirradiation surgical cytoreduction of the tumor was done in 41 dogs. Fifty dogs were irradiated by use of 10 fractions over 22 days, and 17 dogs were given a similar total dose in 5 fractions over 35 days. The range of survival times (0.5 to 42 months), median survival time (8.5 months), and 1- and 2-year survival rates (38% and 30%, respectively) were better than those expected for other methods of treatment. Serious complications were few (4%). Survival times for dogs were determined on the basis of histologic tumor type and on the basis of megavoltage (cobalt or linear accelerator) vs softer deep radiation (cesium or orthovoltage) treatment, with or without cytoreductive surgery. Survival times of 10 dogs given softer radiation without surgery were shorter than those of 14 dogs that were given softer radiation and had cytoreductive surgery. Survival times of dogs that were given softer radiation and had surgery were similar to those of dogs that were given megavoltage radiation only. Cytoreductive surgery did not improve survival times for dogs that were given megavoltage radiation. Median survival time for 38 dogs with adenocarcinoma was 12 months, compared with 6 months for 14 dogs with squamous cell or undifferentiated carcinoma. Median survival time for 16 dogs with a variety of sarcomas was 11.2 months. Survival times of dogs with adenocarcinoma or sarcoma were significantly better (P less than 0.02 or 0.03) than for dogs with squamous cell or undifferentiated carcinoma. Necropsies were performed on 27 of 58 dogs that died or were euthanatized.(ABSTRACT TRUNCATED AT 250 WORDS)     

Analysis of Survival in a Retrospective Study of 86 Dogs with Brain Tumors

A retrospective study of 86 dogs with brain tumors was undertaken. Sixty-nine dogs had histologic confirmation of tumor type, whereas the remaining 17 dogs had CT evidence of a brain tumor. All dogs had neurologic abnormalities. Seven dogs received no treatment, 38 dogs received only symptomatic treatment, and 41 dogs received some form of definitive treatment, in addition to medical management. Types of definitive treatment included surgery, cobalt-60 radiation, whole-body hyperthermia, 125I implants, and chemotherapy, alone or in combination. The factor that was most associated with survival duration was mode of therapy. Those dogs who were treated with cobalt-60 radiation, with or without other combinations of therapy, lived significantly longer than dogs who received surgery (+/- 125I implants), or dogs who received symptomatic treatment (P = 0.01 and P less than 0.001, respectively). After statistic adjustment for treatment, multiplicity of brain involvement (solitary vs. multiple) provided prognostic information with respect to survival (P = 0.001), with dogs who had a solitary site of involvement having a better prognosis. After further adjustment, initial neurologic dysfunction (mild/moderate vs. severe) showed significance as prognostic variable (P = 0.005). Both the mild and moderate groups had a more favorable prognosis compared with dogs who had severe initial neurologic impairment. The median survival time for the 86 dogs was 1.0 month (range: 1 day-42.4 mo). Median survival times of dogs receiving: 1) no therapy or only symptomatic therapy, 2) surgery (+/- 125I), or 3) cobalt-60 radiation (+/- hyperthermia, +/- surgery) were 0.2, 0.9, and 4.9 months, respectively.     

Efficacy and Toxicity of VAC Chemotherapy (Vincristine, Doxorubicin, and Cyclophosphamide) in Dogs with Hemangiosarcoma

Fifteen dogs with hemangiosarcoma were treated with a combination of vincristine, doxorubicin, and cyclophosphamide after incisional or excisional biopsy. The median survival for all fifteen dogs was 172 days (mean survival = 316 days). The median survival for those dogs with splenic hemangiosarcoma was 145 days (mean survival = 271 days) as compared with previously published median survival times in dogs with splenic hemangiosarcoma treated with surgery alone of 19 to 65 days. Toxicities included neutropenia (11/15), severe gastroenteritis (4/15), cardiotoxicity (3/15), and sepsis (2/15). The authors conclude that vincristine, doxorubicin, and cyclophosphamide chemotherapy may be an efficacious treatment modality in dogs with hemangiosarcoma and is associated with acceptable toxicity.     

Outcomes of 35 dogs with craniomaxillofacial osteosarcoma treated with stereotactic body radiation therapy

Canine craniomaxillofacial osteosarcoma (OSA) is most commonly treated surgically; however, in cases where surgery is not feasible or non-invasive treatment is desired, stereotactic body radiation therapy (SBRT) may be elected for local tumour control. In this study, we evaluated 35 dogs treated with SBRT. Nine dogs (26%) had calvarial, seven (20%) had mandibular and 19 (54%) had maxillary OSA. Median time to first event (TFE) was 171 days, and overall median survival time (MST) was 232 days. Site-specific MSTs were 144 days for mandible, 236 days for calvarium and 232 days for maxilla (p = .49). Pulmonary metastatic disease was observed in 12/35 (34%) patients and was detected pre-SBRT in six dogs (17%) and post-SBRT in the remaining six dogs (17%). Eighteen adverse events post-SBRT were documented. Per veterinary radiation therapy oncology group criteria, five were acute (14%) and three were late (9%) grade 3 events. Neurological signs in two dogs were suspected to be early-delayed effects. Cause of death was local progression for 22/35 (63%) patients, metastasis for 9/35 (26%) patients and unknown for four. On univariate analysis, administration of chemotherapy was associated with a longer TFE (p = .0163), whereas volume of gross tumour volume was associated with a shorter TFE (p = .023). Administration of chemotherapy and five fractions versus single fraction of SBRT was associated with increased survival time (p = .0021 and .049). Based on these findings, a treatment protocol incorporating chemotherapy and five fractions of SBRT could be considered for dogs with craniomaxillofacial OSA electing SBRT with careful consideration of normal tissues in the field.