Response-based modification of CHOP chemotherapy for canine B-cell lymphoma.

Despite high initial response rates, a subset of dogs with B-cell lymphoma responds less robustly to CHOP-based chemotherapy and experiences shorter survival. One hundred and four dogs with nodal B-cell lymphoma were treated with a response-based CHOP (RBCHOP) protocol modified based on response to individual drugs during the first chemotherapy cycle. Dogs achieving complete (CR) or partial response (PR) at week 3, following treatment with vincristine and cyclophosphamide, received RBCHOP 1 (n = 72), a protocol sequentially rotating vincristine, cyclophosphamide, and doxorubicin.

Factors influencing complications following mastectomy procedures in dogs with mammary gland tumors: 140 cases (2009-2015).

Objective: To evaluate complication rates for various types of mastectomy procedures, identify factors associated with an increased risk of complications, and determine the consequences of such complications.

Animals: 140 female dogs that underwent 154 separate mastectomy procedures to treat mammary gland tumors.

Procedures: Medical records of dogs in the Penn Vet Shelter Canine Mammary Tumor Program from July 2009 to March 2015 were reviewed.

Modeling molecular development of breast cancer in canine mammary tumors.

Understanding the changes in diverse molecular pathways underlying the development of breast tumors is critical for improving diagnosis, treatment, and drug development. Here, we used RNA-profiling of canine mammary tumors (CMTs) coupled with a robust analysis framework to model molecular changes in human breast cancer. Our study leveraged a key advantage of the canine model, the frequent presence of multiple naturally occurring tumors at diagnosis, thus providing samples spanning normal tissue and benign and malignant tumors from each patient.

Intratumoral collagen signatures predict clinical outcomes in feline mammary carcinoma.

Breast cancer is the most common cause of cancer-related deaths in women worldwide. Identification of reliable prognostic indicators and therapeutic targets is critical for improving patient outcome. Cancer in companion animals often strongly resembles human cancers and a comparative approach to identify prognostic markers can improve clinical care across species.

A prospective randomized trial of desmopressin in canine mammary carcinoma.

Metastatic disease represents a serious and often fatal development in patients with solid tumours, including women with breast cancer and dogs with mammary tumours. Therefore, preventing and treating metastatic disease has remained a priority in cancer research. Desmopressin, a synthetic derivative of vasopressin, traditionally used to treat patients with bleeding disorders, has been proposed as a potential anti-metastatic agent due to its effect on haemostasis as well as multiple other anti-proliferative and anti-angiogenic mechanisms.

The estrogen effect; clinical and histopathological evidence of dichotomous influences in dogs with spontaneous mammary carcinomas.

The purpose of this study was to investigate the associations and explore the relationships between hormonal factors (serum estrogen, estrogen receptors and ovariohysterectomy) and other clinical/histological prognostic factors and their impact on outcome in dogs with mammary carcinomas. Data from two separate prospective studies on dogs with spontaneous mammary carcinomas were used for this research. All dogs underwent standardized diagnostic testing, staging, surgery and follow-up examinations.

Treating the locoregional lymph nodes with radiation and/or surgery significantly improves outcome in dogs with high-grade mast cell tumours.

High-grade canine mast cell tumours (HG-MCT) have a high rate of locoregional relapse. In this study, dogs with HG-MCT treated with radiation therapy (RT) were retrospectively evaluated to determine the benefit associated with treating the locoregional lymph nodes (LNs). Forty-two dogs were included.

Developing and testing prognostic bio-scoring systems for canine mammary gland carcinomas.

Canine mammary carcinomas (CMC) represent a range of histolopathological subtypes with diverse biological behaviours. Several individual factors, including stage, grade, subtypes and presence of invasion, predict outcome. Less is known how these factors interact and impact prognosis.

Diagnosis and Multimodal Treatment of Metastatic Maxillofacial Juvenile Embryonal Rhabdomyosarcoma in a Young Golden Retriever.

A 2 yr old male castrated golden retriever was evaluated for a rapidly progressing maxillofacial spindle cell tumor. On examination, an ill-defined left maxillary mass, a 2 cm swelling under the left eye, and an enlarged left mandibular lymph node were noted. The dog was bright and alert but appeared painful upon jaw extension.

Characteristics of the Epithelial-Mesenchymal Transition in Primary and Paired Metastatic Canine Mammary Carcinomas.

The epithelial-mesenchymal transition (EMT) is a dynamic process linked to metastasis in many tumor types, including mammary tumors. In this study, we evaluated E-cadherin and vimentin immunolocalization in primary canine mammary carcinomas (20 cases) and their respective metastases, as well as their relationship with the core regulators SNAIL/SLUG. To assess the number of cells undergoing the process of EMT, we quantitated double-positive (E-cadherin/vimentin) cells using immunofluorescence, via cell counting and image analysis.

Investigating Associations Between Proliferation Indices, C-kit, and Lymph Node Stage in Canine Mast Cell Tumors.

Previous studies have evaluated cellular proliferation indices, KIT expression, and c-kit mutations to predict the clinical behavior of canine mast cell tumors (MCTs). The study purpose was to retrospectively compare mitotic index, argyrophilic nucleolar organizer regions (AgNORs)/nucleus, Ki-67 index, KIT labeling pattern, and internal tandem duplication mutations in c-KIT between stage I and stage II grade II MCTs. Medical records and tumor biopsy samples from dogs with Grade II MCTs with cytological or histopathological regional lymph node evaluation were included.

Identification of prognostic collagen signatures and potential therapeutic stromal targets in canine mammary gland carcinoma.

Increasing evidence indicates that the tumor microenvironment plays a critical role in regulating the biologic behavior of breast cancer. In veterinary oncology, there is a need for improved prognostic markers to accurately identify dogs at risk for local and distant (metastatic) recurrence of mammary gland carcinoma and therefore would benefit from adjuvant therapy. Collagen density and fiber organization have been shown to regulate tumor progression in both mouse and human mammary tumors, with certain collagen signatures predicting poor outcomes in women with breast cancer.

Treatment outcomes and prognostic factors of feline splenic mast cell tumors: A multi-institutional retrospective study of 64 cases.

Background: Mast cell tumors (MCT) are common splenic tumors in cats, but there is limited information on treatment outcomes of cats with this disease.

Materials And Methods: This retrospective study evaluated treatment outcomes in 64 cats with splenic MCT. Cats were categorized into the following treatment groups: splenectomy (A, n = 20); splenectomy with chemotherapy (B, n = 20); chemotherapy alone (C, n = 15); or supportive care (D, n = 9).

Effect of Ovariohysterectomy at the Time of Tumor Removal in Dogs with Mammary Carcinomas: A Randomized Controlled Trial.

Background: Ovarian hormones play crucial roles in mammary carcinogenesis. However, whether ovarian ablation by ovariohysterectomy (OHE) improves the prognosis in dogs with mammary carcinomas is unclear.

Objectives: Determine if OHE at the time of mastectomy improves the prognosis in dogs with mammary carcinomas and evaluate if hormonal factors influence the effect of OHE.

Early tumor response to intraarterial or intravenous administration of carboplatin to treat naturally occurring lower urinary tract carcinoma in dogs.

Background: Survival times and tumor responses associated with malignant neoplasia of the lower urinary tract are poor despite the vast array of current treatments. Therefore, the evaluation of alternative treatments, such as intraarterial administration of chemotherapy (IAC) should be considered.

Objective: To describe a technique for superselective catheterization for IAC and to evaluate initial tumor response by ultrasonography after both IAC and intravenous administration of chemotherapy (IVC).

Association between macroscopic appearance of liver lesions and liver histology in dogs with splenic hemangiosarcoma: 79 cases (2004-2009).

Medical records for 79 dogs with confirmed splenic hemangiosarcoma (HSA) following splenectomy were reviewed for information regarding either the presence or absence of macroscopic liver lesions and the histopathological characteristics of the liver. Only 29 of 58 dogs (50%) with grossly abnormal livers had HSA metastasis. No dogs with grossly normal livers had metastasis detected on liver pathology.

Effect of ovariohysterectomy at the time of tumor removal in dogs with benign mammary tumors and hyperplastic lesions: a randomized controlled clinical trial.

Background: Nonmalignant mammary tumors (NMT) are common in intact female dogs. Little is known about the clinical significance of these tumors, and the effect of ovariohysterectomy (OHE) on their development.

Hypothesis: Ovarian hormone ablation through OHE decreases the risk of new tumors and thereby improves long-term prognosis for dogs with NMT.

Evaluation of histological grade and histologically tumour-free margins as predictors of local recurrence in completely excised canine mast cell tumours.

Completeness of mast cell tumour (MCT) excision is determined by assessment of histologically tumour-free margins (HTFM). The HTFM width necessary to prevent local recurrence (LR), recognized as histologic safety margin (HSM) in human oncology, has not been defined. We hypothesized that HTFM width would correlate with risk for LR and high-grade tumours would require wider HTFM than low-grade tumours.

Prospective clinical trial to compare vincristine and vinblastine in a COP-based protocol for lymphoma in cats.

Background: Current standard chemotherapy protocols for lymphoma in cats carry risks of gastrointestinal toxicity, which can decrease quality of life and complicate response assessment. Protocols with less gastrointestinal toxicity may improve treatment tolerance.

Hypothesis/objectives: The study purpose was to compare response rate, outcome, and toxicity between cats that received vincristine or vinblastine as part of combination chemotherapy for lymphoma.

Risk factors for development of sterile haemorrhagic cystitis in canine lymphoma patients receiving oral cyclophosphamide: a case-control study.

Sterile haemorrhagic cystitis (SHC) is a known risk of cyclophosphamide treatment; however, most canine reports are case series. This case-control study examined risk factors for SHC in dogs with lymphoma receiving oral cyclophosphamide. Twenty-two dogs with SHC and 66 control dogs were identified.

Evaluation of factors associated with prolonged hospital stay and outcome of febrile neutropenic patients receiving chemotherapy: 70 cases (1997-2010).

Febrile neutropenia (FN) is an important sequela in veterinary patients receiving chemotherapy. The purpose of this study was to identify factors associated with prolonged hospital stay and outcome in canine patients developing FN secondary to chemotherapy administration. Medical records of 70 dogs treated for FN at the University of Pennsylvania from 1997 to 2010 were retrospectively evaluated.

Clinical, histopathological and immunohistochemical characterization of canine indolent lymphoma.

Indolent lymphoma comprises up to 29% of all canine lymphoma; however, limited information exists regarding the subtypes and biological behaviour. This retrospective study describes the clinical characteristics, histopathological and immunohistochemical features, treatment, outcome and prognostic factors for 75 dogs with indolent lymphoma. WHO histopathological classification and immunohistochemistry (IHC) for CD79a, CD3, Ki67 and P-glycoprotein (P-gp) was performed.

Evaluation of Clostridium novyi-NT spores in dogs with naturally occurring tumors.

Objective: To establish the maximum tolerated dose of Clostridium novyi-NT spores in tumor-bearing dogs and evaluate spore germination within tumors and tumor response.

Animals: 6 client-owned dogs.

Procedures: A standard dose-escalation study was planned, with maximum tolerated dose defined as the highest dose at which 0 or 1 of 6 dogs had dose-limiting toxicoses (DLT).