Neoadjuvant chemoradiotherapy and surgery as treatment for oral maxillary squamous cell carcinoma in a dog

Retrospective Evaluation of a Combination of Carboplatin and Bleomycin for the Treatment of Canine Carcinomas

Carboplatin is a chemotherapy agent widely used in veterinary oncology to treat various types of tumors including carcinomas. Carboplatin has previously been used in combination with 5-Fluoro uracil (5-FU) or gemcitabine for the treatment of various carcinomas. Bleomycin is a chemotherapy drug commonly used in humans, but its use has been uncommonly reported in dogs. The combination of carboplatin and bleomycin chemotherapy treatment has never been reported in dogs. Dogs diagnosed with carcinoma and treated with a combination of carboplatin and bleomycin, at a single veterinary referral center, were retrospectively evaluated. Thirty patients met the inclusion criteria. The dose of carboplatin ranged from 200–250 mg/m2 (median 240 mg/m2) and the dose of bleomycin from 15–20 IU/m2 (median 15 IU/m2). The treatment with carboplatin and bleomycin was well tolerated, with sixteen patients (53%) developing side effects. Thirteen patients (46%) developed gastrointestinal signs and nine dogs (30%) developed hematological abnormalities. The most common side effects were grade-1 hyporexia and grade-1 neutropenia. Grade-2 neutropenia was rarely observed, and only one patient developed grade-3 neutropenia. None of the dogs developed grade-4 adverse events, or required hospitalization, or died due to the treatment. No signs of chronic side effects, including pulmonary toxicity, were observed. Objective response was observed in 24% of the cases (six partial responses) and 76% of cases achieved clinical benefit (partial response+ stable disease). Clinical signs improved in 24 of the 30 cases (80%). The main aim of this study was to evaluate the safety of bleomycin and carboplatin in combination for the treatment of various types of carcinomas. The combination of bleomycin and carboplatin appears safe and potentially effective for some types of carcinomas. Larger prospective studies are needed to confirm the safety and efficacy of combined carboplatin and bleomycin.

Survival time of juvenile dogs with oral squamous cell carcinoma treated with surgery alone: A Veterinary Society of Surgical Oncology retrospective study

OBJECTIVE

To report the signalment, staging, surgical treatment, and survival time of juvenile dogs treated surgically for oral squamous cell carcinoma (OSCC).

STUDY DESIGN

Retrospective study.

ANIMALS OR SAMPLE POPULATION

Twenty-five dogs, <2 years of age with OSCC treated with surgery.

METHODS

Cases were solicited from the Veterinary Society of Surgical Oncology. Data retrieved included sex, breed, age, weight, clinical signs, tumor location, preoperative diagnostics and staging, histopathological diagnosis with margin evaluation, disease-free interval, and date and cause of death. A minimum follow-up time of 3 months was required for inclusion.

RESULTS

Eighteen dogs were <12 months of age, and seven were <24 months. Various breeds were represented, with a mean body weight of 22.3 ± 14.4 kg. No dogs had evidence of metastatic disease prior to surgery. All dogs underwent partial maxillectomy or mandibulectomy. Histological margins were complete in 24 dogs and incomplete in one. No dogs had evidence of metastatic disease or tumor recurrence. The median follow-up time was 1556 days (92 to 4234 days). All dogs were alive at the last follow-up except for one documented death, due to dilated cardiomyopathy. Median disease-specific survival time was not reached.

CONCLUSION

The prognosis after wide surgical excision of OSCC in juvenile dogs was excellent.

CLINICAL SIGNIFICANCE

OSCC in juvenile dogs can be effectively treated with surgery alone.

Evaluation of cytology and histopathology for the diagnosis of canine orbital neoplasia: 112 cases (2004-2019) and review of the literature

OBJECTIVE

To provide an updated overview of canine orbital neoplasia, to compare diagnostic utility of cytology and histopathology, and to evaluate alternative sampling modalities, particularly image-guided core needle biopsy.

PROCEDURES

A medical records search was performed to identify dogs with orbital neoplasia. Data were collected regarding signalment, diagnosis, vision status, imaging modalities, and sample collection methods. A reference population with orbital neoplasia was also identified via literature search for comparison with regard to final diagnosis.

RESULTS

One hundred and twelve dogs met selection criteria. In the study and reference populations, respectively, diagnoses were grouped as follows: mesenchymal tumors 40% and 35%, epithelial tumors 35% and 18%, tumors of neural origin 8% and 37%, and round cell 17% and 10%. The most common diagnoses in the study group were nasal adenocarcinoma, osteosarcoma, lymphoma, and meningioma. Cytology results were available for 47 dogs and histopathology results were available for 95 dogs. Both cytology and histopathology results were available for 30 dogs, in 53% of which results were discordant. Cytology samples were nondiagnostic or provided a diagnosis that was later overturned in 32% of cases in which they were obtained. Results from core needle biopsy samples were nondiagnostic or overturned by surgical biopsy results in only 13% of cases. No significant complications were associated with any sampling method.

CONCLUSIONS

Orbital neoplasia is common in dogs. Histopathology is superior to cytology in providing a definitive diagnosis. Image-guided core needle biopsy appears to be a safe and effective means of obtaining samples.

Molecular iodine/doxorubicin neoadjuvant treatment impair invasive capacity and attenuate side effect in canine mammary cancer

Background

Mammary cancer has a high incidence in canines and is an excellent model of spontaneous carcinogenesis. Molecular iodine (I₂) exerts antineoplastic effects on different cancer cells activating re-differentiation pathways. In co-administration with anthracyclines, I₂ impairs chemoresistance installation and prevents the severity of side effects generated by these antineoplastic drugs. This study is a random and double-blind protocol that analyzes the impact of I₂ (10 mg/day) in two administration schemes of Doxorubicin (DOX; 30 mg/m2) in 27 canine patients with cancer of the mammary gland. The standard scheme (sDOX) includes four cycles of DOX administered intravenously for 20 min every 21 days, while the modified scheme (mDOX) consists of more frequent chemotherapy (four cycles every 15 days) with slow infusion (60 min). In both schemes, I₂ or placebo (colored water) was supplemented daily throughout the treatment.

Results

mDOX attenuated the severity of adverse events (VCOG-CTCAE) in comparison with the sDOX group. The overall tumor response rate (RECIST criteria) for all dogs was 18% (interval of reduction 48–125%), and no significant difference was found between groups. I₂ supplementation enhances the antineoplastic effect in mDOX, exhibiting a significant decrease in the tumor epithelial fraction, diminished expression of chemoresistance (MDR1 and Survivin) and invasion (uPA) markers and enhanced expression of the differentiation factor known as peroxisome proliferator-activated receptors type gamma (PPARγ). Significant tumor lymphocytic infiltration was also observed in both I₂-supplemented groups. The ten-month survival analysis showed that the entire I₂ supplementation (before and after surgery) induced 67–73% of disease-free survival, whereas supplementation in the last period (only after surgery) produced 50% in both schemes.

Conclusions

The mDOX+I₂ scheme improves the therapeutic outcome, diminishes the invasive capacity, attenuates the adverse events and increases disease-free survival. These data led us to propose mDOX+I₂ as an effective treatment for canine mammary cancer.