Efficacy of Combination Chemotherapy for Treatment of Gastrointestinal Lymphoma in Dogs

Background: Chemotherapy for multicentric canine lymphoma has favorable results. The gastrointestinal (GI) tract is the most common extranodal site of canine lymphoma, but there have been no prospective studies to determine outcome when dogs with GI lymphoma are treated with chemotherapy.
Hypothesis: Treatment with a multiagent chemotherapy protocol is associated with a poor outcome in dogs with GI lymphoma.
Animals: Eighteen dogs with histologically confirmed GI lymphoma.
Methods: Prospective clinical trial in which dogs with GI lymphoma were treated with a 20-week combination chemotherapy protocol consisting of induction and consolidation phases.
Results: Thirteen dogs had primary GI lymphoma and 5 had multicentric lymphoma with GI involvement. The majority of the lymphomas (63%) were of T-cell origin. Overall remission rate was 56%; 9 dogs achieved a complete remission for a median of 86 days (range, 22–420 days) and 1 dog achieved a partial remission for 26 days. Overall median survival time was 77 days (range, 6–700 days). Dogs that failed to achieve a remission (10 versus 117 days; P = .002) or had diarrhea at initial presentation (70 versus 700 days; P < .001) had shorter survival times.
Conclusion and Clinical Importance: The response and survival of dogs with GI lymphoma treated with multiagent chemotherapy is poor but long-term survival is possible.     

CHOP chemotherapy for the treatment of canine multicentric T-cell lymphoma

Dogs with multicentric T-cell lymphoma are commonly treated with CHOP chemotherapy protocols that include cyclophosphamide, doxorubicin, vincristine and prednisone. The purpose of this study was to evaluate the use of CHOP chemotherapy for dogs with multicentric T-cell lymphoma. Identification of prognostic factors in this specific subset of dogs was of secondary interest. Twenty-three out of 24 dogs responded to CHOP chemotherapy and these dogs remained on the protocol for a median of 146 days. No variable was associated with progression free survival (PFS) including stage, substage, hypercalcemia or radiographic evidence of a cranial mediastinal mass. The median overall survival time (OST) for all dogs was 235 days. Dogs that were thrombocytopenic at presentation experienced a significantly longer OST (323 versus 212 days, P=0.01).     

Evaluation of an actinomycin-D-containing combination chemotherapy protocol with extended maintenance therapy for canine lymphoma

In this retrospective study, a 6-drug (prednisone, L-asparaginase, vincristine, cyclophosphamide, doxorubicin, and actinomycin-D) chemotherapy protocol with extended maintenance for the treatment of lymphoma was evaluated for efficacy and toxicity in 39 dogs. The complete remission rate was 97%, with a median progression-free survival (PFS) of 331 d. The median overall survival (OS) was 461 d. Of the variables evaluated for prognostic significance, only immunophenotype and sex were found to be prognostic. Dogs with T-cell lymphoma had shorter PFS and OS than dogs with B-cell lymphoma. Castrated male dogs had a shorter PFS and OS than spayed female dogs. Although the majority of dogs experienced one or more episodes of chemotherapy associated toxicity, the majority of these episodes were mild and self-limiting. The results of this study warrant further investigation into the value of extended maintenance therapy and inclusion of actinomycin-D in combination chemotherapy protocols for canine lymphoma.     

Efficacy and toxicosis of VELCAP-C treatment of lymphoma in cats

Background: Lymphoma is the most common malignancy affecting cats. A protocol employing vincristine, l -asparaginase, cyclophosphamide, doxorubicin, and prednisone (VELCAP-S) is effective and well tolerated in dogs with lymphoma. A 24-week variation of this protocol (VELCAP-C) was developed for treatment of cats.
Hypothesis: That VELCAP-C will result in survival times for cats with lymphoma that are similar to those obtained when cats are treated with a protocol that includes fewer chemotherapy agents.
Animals: Sixty-one cats with lymphoma.
Methods: Retrospective study. Outcomes evaluated were response to VELCAP-C therapy, toxicosis, and survival time. The effect of signalment, staging, CBC, and serum chemistry profile and dosage on these outcomes was examined.
Results: Six cats (10%) completed the protocol with a median survival of 1189 days. Forty-three percent (23 of 61) of the cats achieved complete response (CR) with a median survival time of 62 days. Cats that required a dose reduction of any drug during induction were more likely to achieve CR. Weight loss and hepatomegaly at diagnosis were negatively associated with response to treatment. Increased lactate dehydrogenase (LDH) serum activity at the time of initial treatment correlated with decreased survival times.
Conclusions and Clinical Importance: This multi agent protocol did not provide improved survival over historical data using protocols with fewer agents. Serum LDH activity levels might provide useful prognostic information for cats with lymphoma.     

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.     

Clinical characteristics, treatment, and outcome of dogs with presumed primary hepatic lymphoma: 18 cases (1992-2008)

OBJECTIVE-To determine outcome of dogs with presumed primary hepatic lymphoma treated with various multiagent, doxorubicin-based chemotherapeutic protocols and identify factors associated with prognosis. DESIGN-Retrospective case series. ANIMALS-18 dogs with presumed primary hepatic lymphoma. PROCEDURES-Medical records were reviewed for information on signalment, treatment, and outcome. RESULTS-8 dogs had a complete remission (CR), with a median remission duration of 120 days. Dogs with leukocytosis, neutrophilia, hypoalbuminemia, hyperbilirubinemia, or a combination of hypoalbuminemia and hyperbilirubinemia were less likely to achieve a CR. Overall median survival time (MST) was 63 days (range, 2 to 402 days). In a multivariate analysis, response to treatment and serum albumin concentration were associated with MST. Dogs that did not achieve a CR had a significantly shorter MST than did dogs that did achieve a CR (13 vs 283 days, respectively). Dogs with serum albumin concentration < 2.5 g/dL at the time treatment was initiated had a significantly shorter MST than did dogs with serum albumin concentration within reference limits (10 vs 128 days, respectively). There was also a positive correlation between serum albumin concentration and survival time (r = 0.74). CONCLUSIONS AND CLINICAL RELEVANCE-Results suggested that dogs with primary hepatic lymphoma that underwent chemotherapy had a poor prognosis, with a low response rate. Dogs that responded to treatment had a better prognosis, and dogs with hypoalbuminemia had a poorer prognosis.     

Evaluation of Single-Agent Mitoxantrone as Chemotherapy for Relapsing Canine Lymphoma

Many chemotherapeutic regimens will induce remission in dogs with lymphoma, but almost all dogs suffer relapse. Mitoxantrone was selected for evaluation as single-agent chemotherapy for relapsing canine lymphoma based on its use in humans undergoing salvage chemotherapy for non-Hodgkin's lymphoma and its tumoricidal effect against canine lymphoma. Dogs entered into study had multicentric lymphoma, and all had been treated solely with a standard combination chemotherapy protocol. At 1st relapse, all dogs were again staged and underwent lymph node biopsy. Mitoxantrone was administered IV at 6 mg/m² every 21 days. Dogs were evaluated for lymphadenopathy before each dose of mitoxantrone. Fifteen dogs were entered into study. The average age (±SEM) of the dogs studied was 7.7 ± 0.91 years, and most dogs were large (mean ± SEM weight, 24.44 ± 2.15 kg). Twelve dogs (80%) had B-cell lymphoma, and 3 had T-cell lymphoma. Dogs were staged IV (n = 12) or V (n = 3). The median duration of chemotherapy before entry into the study was 98 days. Overall median duration of response after mitoxantrone chemotherapy was 21 days. Complete responses were attained in 7 of 15 dogs (47%) with a median response duration of 84 days. Nine of 15 (60%) dogs attained a complete remission with additional chemotherapy after failing mitoxantrone chemotherapy. Mild toxicities were observed after mitoxantrone administration. No adverse reactions were observed during mitoxantrone infusions. The results of this study demonstrate that mitoxantrone, as a single agent, has limited value for dogs with lymphoma at 1st relapse after conventional multidrug chemotherapy.     

Response rates and survival times for cats with lymphoma treated with the University of Wisconsin-Madison chemotherapy protocol: 38 cases (1996-2003)

OBJECTIVE: To determine response rates and survival times for cats with lymphoma treated with the University of Wisconsin-Madison chemotherapy protocol. DESIGN: Retrospective study. ANIMALS: 38 cats with lymphoma. PROCEDURE: Medical records were reviewed, and information on age, sex, breed, FeLV and FIV infection status, anatomic form, clinical stage, and survival time was obtained. Immunophenotyping was not performed. RESULTS: Mean +/- SD age of the cats was 10.9 +/- 4.4 years. Overall median survival time was 210 days (interquartile range, 90 to 657 days), and overall duration of first remission was 156 days (interquartile range, 87 to 316 days). Age, sex, anatomic form, and clinical stage were not significantly associated with duration of first remission or survival time. Eighteen of the 38 (47%) cats had complete remission, 14 (37%) had partial remission, and 6 (16%) had no response. Duration of first remission was significantly longer for cats with complete remission (654 days) than for cats with partial remission (114 days). Median survival time for cats with complete remission (654 days) was significantly longer than median survival time for cats with partial remission (122 days) and for cats with no response (11 days). CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that a high percentage of cats with lymphoma will respond to treatment with the University of Wisconsin-Madison chemotherapy protocol. Age, sex, anatomic form, and clinical stage were not significantly associated with duration of first response or survival time, but initial response to treatment was.     

Actinomycin D as rescue therapy in dogs with relapsed or resistant lymphoma: 49 cases (1999--2006)

OBJECTIVE: To evaluate response rate and disease-free interval in dogs with relapsed or resistant lymphoma treated with actinomycin D, determine hematologic toxicoses, and identify prognostic factors associated with response to treatment. DESIGN: Retrospective case series. ANIMALS: 49 dogs with relapsed or resistant lymphoma. PROCEDURES: Medical records were reviewed for information regarding signalment, physical examination findings, results of diagnostic testing, substage, previous chemotherapy, previous treatment with prednisone, actinomycin D dosage, number of doses administered, response, disease-free interval, and results of CBCs performed after treatment. RESULTS: Actinomycin D was administered at a median dosage of 0.68 mg/m2 (range, 0.46 to 0.72 mg/m2), IV, every 3 weeks for 5 treatments or until disease progression. Twenty-six (53%) dogs received prednisone concurrently. Twenty (41%) dogs had a complete remission, and median disease-free interval in these dogs was 129 days. Thrombocytopenia was the most common hematologic toxicosis (n = 22 [45%]). Concurrent prednisone administration, a shorter duration of first remission, and an increased number of previous chemotherapy agents were significantly associated with a lower likelihood of responding to actinomycin D treatment. Concurrent prednisone administration and an increased number of previous chemotherapy agents were significantly associated with a shorter disease-free interval. CONCLUSION AND CLINICAL RELEVANCE: Results suggested that administration of actinomycin D as a single agent was effective for rescue chemotherapy of dogs with relapsed or resistant lymphoma and that treatment was well tolerated, although mild thrombocytopenia developed commonly.     

Does l‐Asparaginase Influence Efficacy or Toxicity When Added to a Standard CHOP Protocol for Dogs with Lymphoma?

The purpose of this study was to evaluate response rates, 1st remission duration (FRD), and toxicity in dogs with previously untreated lymphoma receiving an identical CHOP-based combination chemotherapy protocol with or without L-asparaginase (LASP). One hundred fifteen dogs with lymphoma were scheduled to receive an identical CHOP-based chemotherapy protocol that included L-ASP. However, because of manufacturer-imposed random rationing, 31 dogs did not receive L-ASP as scheduled. The 2 treatment groups were statistically similar with respect to signalment and presence of historical negative prognostic factors. No difference was observed in the median FRD whether dogs did or did not receive L-ASP (206 versus 217 days, respectively; P = .67). No difference was observed in the median overall survival times between dogs receiving or not receiving L-ASP (310 versus 308 days, respectively; P = .84). No statistical difference was observed with respect to overall response rate between dogs that did or did not receive L-ASP (89.3% versus 87.1%, respectively; P = .75). Complete response rates between the groups also were no different (83.3% and 77.4% for L-ASP and non-L-ASP groups, respectively; P = .59). Prevalence of toxicity (neutropenia, diarrhea, or vomiting) and treatment delays (P = .80) also were similar between groups. The results of this study suggest that exclusion of L-ASP in this multidrug protocol does not significantly impact outcome. Therefore, it may be more appropriate to reserve the use of L-ASP for treating relapse in dogs with lymphoma that have failed induction therapy.     

Reevaluation of the University of Wisconsin 2-year protocol for treating canine lymphosarcoma

This retrospective study investigated a population of 96 dogs with newly diagnosed malignant lymphosarcoma that were treated with the commonly used University of Wisconsin-Madison (UW-M) chemotherapy protocol. Pretreatment characteristics were analyzed to determine prognostic factors. Dogs with higher World Health Organization (WHO) stages (including stage IV) and dogs with hypercalcemia were at significantly higher risk of relapse (P=0.018 and P=0.016, respectively). Dose reduction, treatment delays, and prior therapy with cortico-steroids were not associated with clinical outcome. First remission duration of 270 days was similar to historically reported data. Overall survival time of 218 days was much shorter than historical data.     

Prognostic significance of hypermethylation of death‐associated protein kinase (DAPK) gene CpG island in dogs with high‐grade B‐cell lymphoma

Death‐associated protein kinase (DAPK) is a serine/threonine kinase and a tumour suppressor gene. Diffuse large B‐cell lymphomas with inactivated DAPK through hypermethylation of a CpG island is known to result in a biologically aggressive phenotype in humans. This retrospective study was carried out to analyse the prognostic significance of DAPK CpG island hypermethylation in canine lymphoma. We hypothesized that DAPK CpG island hypermethylation can be a negative prognostic indicator in dogs with nodal high‐grade B‐cell lymphoma. Forty‐seven dogs with high‐grade B‐cell lymphoma, according to the updated Kiel classification, were evaluated after being treated with a CHOP (vincristine, cyclophosphamide, doxorubicin and prednisolone)‐based chemotherapy protocol. The methylation status of the DAPK CpG island was examined by methylation‐specific PCR. Progression‐free survival (PFS) and overall survival (OS) were compared using the Kaplan‐Meier analysis and log‐rank test. The cox proportional hazard regression model was used to evaluate the effect of multiple variables. Hypermethylation of the DAPK CpG island was detected in 21 of the 47 dogs. The PFS and OS in dogs with the hypermethylation (median: 220 and 266 days, respectively) were significantly shorter than those of dogs without hypermethylation (median: 301 and 412 days, respectively) (PFS, P = .036; OS, P = .007). In the multivariate analysis, hypermethylation of the DAPK CpG island remained an independent prognostic factor in predicting shortened PFS (P = .047) and OS (P = .021) as well as clinical substage b. Overall, hypermethylation of the DAPK CpG island was a negative prognostic factor in canine high‐grade B‐cell lymphoma.     

Survival Analysis of 97 Cats with Nasal Lymphoma: A Multi-Institutional Retrospective Study (1986–2006)

Background: Feline nasal lymphoma (NLSA) is a condition for which no standard of care exists.
Hypothesis: There is no difference in survival times of cats with NLSA treated with single or multimodality therapy.
Animals: Records from 97 cats diagnosed with NLSA were examined.
Methods: The purpose of this retrospective study was to compare the survival times of cats with NLSA treated with radiation therapy (RT) alone, chemotherapy alone, or RT + chemotherapy and identify potential prognostic variables that affected survival. Cats were grouped according to therapy: RT + chemotherapy (n = 60), RT alone (n = 19), or chemotherapy alone (n = 18).
Results: Survival was calculated with 2 methods. The 1st survival analysis (method A) included all cats, but counted only deaths caused by progressive NLSA. The median survival time (MST), regardless of therapy modality, was 536 days. The 2nd survival analysis (method B) also included all cats and counted all deaths, regardless of cause, as events. The overall MST calculated for all deaths was 172 days. A negative independent prognostic variable identified was anemia ( P < .001), and positive independent prognostic variables were a complete response to therapy ( P < .001) and total radiation dose >32 Gy ( P = .03).
Conclusions and Clinical Importance: There were no significant differences in survival times among the 3 treatment groups but these results suggest that the addition of higher doses of RT to a cat's treatment protocol may control local disease and therefore influence survival.     

Feline extranodal lymphoma: response to chemotherapy and survival in 110 cats

O bjective : To determine response to treatment, survival and prognostic factors for feline extranodal lymphoma in the UK.
M ethods : Records of cats diagnosed with lymphoma of extranodal sites at seven referral centres were reviewed and information on signalment, tumour location, prior treatment and chemotherapy protocol recorded. Factors influencing response to treatment and survival were assessed.
R esults : One hundred and forty-nine cases met inclusion criteria. Sixty-nine cats had nasal lymphoma, 35 renal, 15 central nervous system, 11 laryngeal and 19 miscellaneous locations. Sixty-six cats received cyclophosphamide, vincristine, prednisolone, 25 Wisconsin-Madison doxorubicin-containing multi-agent protocol, 10 prednisolone alone and nine other combinations. The response rate for the 110 treated cats was 85·5 per cent. Of cyclophosphamide, vincristine, prednisolone treated cats 72·7 per cent achieved complete remission, median survival 239 days. Sixty-four per cent of Wisconsin-Madison treated cats achieved complete remission, median survival 563 days. Cats with nasal lymphoma achieving complete remission had the longest survival (749 days) and cats with central nervous system lymphoma the shortest (70 days). If complete remission was achieved, prior treatment with corticosteroids significantly reduced survival time.
C linical S ignificance : Cats with extranodal lymphoma respond to chemotherapy and achieve survival times comparable to other locations. Corticosteroid pretreatment reduced survival time in cats achieving complete remission.     

Clinical presentation,treatment and outcome in 31 dogs with presumed primary colorectal lymphoma (2001–2013)

The objective of this multicentre retrospective study was to describe clinical presentation, treatment and outcome and to determine prognostic factors for dogs with presumed primary colorectal lymphoma (PCRL). A total of 31 dogs were included. The predominant features of PCRL were high grade (n = 18) and immunophenotype B (n = 24). Most dogs were substage b (n = 25) with higher prevalence of haematochezia (n = 20). One dog had surgery only. Thirty dogs received chemotherapy; amongst them 13 had surgery or radiotherapy. Progression free survival (PFS) was 1318 days and disease‐related median survival time (MST) was 1845 days. Fourteen dogs were alive at the end of the study with a median follow‐up time of 684 days (3–4678 days). Younger dogs had longer PFS (P = 0.031) and disease‐related MST (P = 0.01). Presence of haematochezia corresponded with longer PFS (P = 0.02). Addition of local treatment to chemotherapy did not significantly improve the outcome (P = 0.584). Canine PCRL has considerably longer PFS and MST than other forms of non‐Hodgkin's lymphoma.     

Comparison of COAP and UW-19 protocols for dogs with multicentric lymphoma

BACKGROUND: Various chemotherapy protocols for treating lymphoma in dogs have been published; however, comparison of protocols from different studies is difficult, especially when evaluating survival time and toxicoses. HYPOTHESIS: The choice of COAP (C, cyclophosphamide; O, vincristine; A, cytosine arabinoside; P, prednisone) and a modified University of Wisconsin 19-week (UW-19) induction protocol has no influence on overall survival times in dogs with lymphoma. ANIMALS: One hundred and one dogs with multicentric lymphoma. METHODS: Retrospective study (2001-2006). Dogs induced with either an 8-week COP-based protocol (C, cyclophosphamide; O, vincristine; and P, prednisone) with maintenance therapy (COAP group) or a 19-week CHOP (C, cyclophosphamide; H, doxorubicin; O, vincristine; and P, prednisone) based protocol (UW-19 group) were compared in terms of the duration of first remission, survival time, toxicoses, and cost. RESULTS: There were 71 dogs in the COAP group and 30 dogs in the UW-19 group. Various protocols were used after the first relapse. The median duration of the first remission for the COAP and UW-19 groups were 94 days (range, 6-356 days) and 174 days (28-438 days), respectively (P < .01). The median survival times for dogs in the COAP and UW-19 groups were 309 days (6-620 days) and 275 days (70-1102+ days), respectively (P = .09). Dogs in the COAP group had a hazard ratio of 1.9 (95% CI 1.1-3.4) for death relative to the UW-19 group (P = .03), after controlling for the confounders (World Health Organization clinical stage, age, sex, use of doxorubicin during reinduction). The severity of neutropenia and gastrointestinal toxicoses were significantly higher in the UW-19 group than in the COAP group (P = .01 and P < .01, respectively). CONCLUSION AND CLINICAL IMPORTANCE: Use of a long-term doxorubicin-containing sequential combination chemotherapy protocol is associated with a decreased risk of relapse and death relative to a non-doxorubicin-containing protocol.     

Asparaginase and MOPP Treatment of Dogs with Lymphoma

Background: Dogs with multicentric lymphoma are treated with various cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP)-based chemotherapy protocols with variable success.
Objectives: To describe the progression-free survival (PFS) time and overall survival time (OST) of dogs with T-cell lymphoma or hypercalcemic lymphoma treated with l -asparaginase and mechlorethamine, vincristine, prednisone, procarbazine (MOPP).
Animals: Fifty dogs with T-cell lymphoma, hypercalcemic lymphoma, or both treated at 3 referral veterinary hospitals.
Methods: Retrospective study. Case were selected based on histologic or cytologic diagnosis of lymphoma; presence of the T-cell phenotype, presence of hypercalcemia or both; and absence of previous chemotherapy. The T-cell phenotype was determined by flow cytometry, immunocytochemistry, immunohistochemistry, or polymerase chain reaction of antigen receptor rearrangement.
Results: The overall response rate was 98% (78% complete response, 20% partial response). The median PFS for the entire study population was 189 days with 25% PFS at 939 days. The median OST for the entire study population was 270 days with 25% surviving 939 days. Twenty percent of the dogs required hospitalization for treatment related complications.
Conclusions and clinical importance: l -Asp/MOPP chemotherapy might result in longer PFS and OST for dogs with multicentric T-cell lymphoma, dogs with hypercalcemic lymphoma or both, than achieved with CHOP.     

Evaluation of Prognostic Factors and Sequential Combination Chemotherapy With Doxorubicin for Canine Lymphoma

Fifty-five dogs with lymphoma were treated using a doxorubicin-based sequential combination chemotherapy protocol. Complete response, partial response, and no response were seen in 46, 4, and 5 dogs, respectively. The overall median remission duration and survival times were 36 and 51 weeks, respectively. Age, sex, weight, World Health Organization stage, World Health Organization substage (i.e., a = not ill, b = ill), serum calcium concentration, blood urea nitrogen concentration, breed, and protocol alteration secondary to toxicity were evaluated for prognostic significance. Univariate analysis of prognostic factors identified sex, World Health Organization substage, and serum calcium as statistically significant ( P ≤ .05) variables for both survival and remission duration. Upon multivariate analysis, only substage ( P = .036) was a significant prognostic factor for remission duration, whereas, both substage ( P = .006) and sex ( P = .005) were significant prognostic factors for survival. (Journal of Veterinary Internal Medicine 1993; 7:289–295. Copyright © 1993 by the American College of Veterinary Internal Medicine.)     

Sequential Low-Dose Rate Half-Body Irradiation and Chemotherapy for the Treatment of Canine Multicentric Lymphoma

Background: Sequential half-body irradiation (HBI) combined with chemotherapy is feasible in treating canine lymphoma, but prolonged interradiation intervals may affect efficacy. A 2-week interradiation interval is possible in most dogs receiving low-dose rate irradiation (LDRI) protocols at 6 Gy dose levels.
Hypothesis: LDRI incorporated into a cyclophosphamide, doxorubicin, vincritine, and prednisone (CHOP)-based chemotherapy protocol is effective for the treatment of lymphoma in dogs.
Animals: Thirty-eight client-owned animals diagnosed with multicentric lymphoma.
Methods: Retrospective study evaluating the efficacy and prognostic factors for the treatment of canine lymphoma with sequential HBI and chemotherapy.
Results: The median 1st remission was 410 days (95% confidence interval [CI] 241–803 days). The 1-, 2-, and 3-year 1st remission rates were 54, 42, and 31%. The median overall survival was 684 days (95% CI 334–1,223 days). The 1-, 2-, and 3-year survival rates were 66, 47, and 44%.
Conclusions and Clinical Relevance: Results of this study suggest that treatment intensification by a 2-week interradiation treatment interval coupled with interradiation chemotherapy is an effective treatment for dogs with lymphoma.     

Epirubicin as part of a multi‐agent chemotherapy protocol for canine lymphoma

The aim of the study was to report the outcome of treatment of 97 dogs with lymphoma that received a multi‐agent chemotherapy protocol containing epirubicin as the primary anthracycline. Seventy‐five dogs received a 25‐week protocol with no maintenance phase whilst 22 dogs received a maintenance phase. Complete response rate was 96% and time to first relapse (TTR) and overall survival (OS) time for all dogs were 216 and 342 days, respectively. Dogs with T‐cell lymphoma and those classified as WHO substage b had significantly poorer OS times and TTR. The protocol was well tolerated with toxicity similar to doxorubicin‐containing protocols. Epirubicin as part of a multi‐agent protocol is safe and effective in the treatment of canine multicentric lymphoma. There is a high initial response rate and an overall median survival time that is similar to other published doxorubicin‐containing protocols.