Outcome in 27 Dogs with Curative-Intent Treatment of Localized Primary Pulmonary Histiocytic Sarcoma
2020 VCS Virtual Conference
Caroline Murray1; Jennifer Willcox1; Carlos De Mello Souza2; Brian Husbands3; Matthew Cook3; Craig Clifford4; Haley Leeper5; MacKenzie Pellin6; Danielle Richardson7; Chamisa Herrera8; Erika Krick9; Sarah McMillan10; Sami Al-Nadaf1; Katherine Skorupski1
1University of California, Davis, CA, USA; 2University of Florida, Gainesville, FL, USA; 3The Ohio State University, Columbus, OH, USA; 4Hope Veterinary Specialists, Malvern, PA, USA; 5Oregon State University, Corvallis, OR, USA; 6University of Wisconsin-Madison, Madison, WI, USA; 7Ontario Veterinary College, Guelph, ON, Canada; 8Boundary Bay Veterinary Specialty Hospital, Vancouver, BC, Canada; 9Mount Laurel Animal Hospital, Mount Laurel, NJ, USA; 10Veterinary Emergency Referral Center of Hawaii, Honolulu, HI, USA
Introduction
Primary pulmonary histiocytic sarcoma (PHS) is a rare form of dendritic cell neoplasia originating within the pulmonary parenchyma. There is limited literature describing prognosis in dogs with PHS receiving curative-intent treatment consisting of surgical excision and adjuvant systemic chemotherapy. The primary objective of this study was to gain insight on localized primary PHS and provide information on outcome with standardized local and systemic therapy. A secondary objective was to identify prognostic factors in this population.
Methods
A multi-institutional study was performed, and medical records were retrospectively reviewed. For inclusion, dogs were required to have confirmed localized PHS and they must have undergone curative-intent surgery with resection of all gross primary tumor and involved lymph nodes; additionally, they must have received treatment with adjuvant single-agent CCNU chemotherapy.
Results
Twenty-seven dogs from 11 institutions were included in analyses. The overall median survival time (MST) was 432 days. Only CCNU dose was found to be associated with survival in this population. The MST for dogs prescribed less than the median dose (66.6 mg/m2) was 673 days vs 200.5 days for dogs prescribed greater than or equal to 66.6 mg/m2 (p=0.005). Factors that were not found to be associated with survival included body weight, breed, symptoms at diagnosis, hypoalbuminemia, tumor size, lung location, lymph node metastasis, surgical margins, and CCNU dose reductions.
Conclusion
Dogs diagnosed with localized PHS and treated with curative-intent surgery and adjuvant CCNU chemotherapy have a relatively favorable prognosis and aggressive treatment may be advisable to attempt to prolong survival.
Funding Information
N/A