A case report of total skin photon radiation therapy for cutaneous epitheliotropic lymphoma in a dog

Abstract

BackgroundTotal skin electron beam radiation therapy (TSEBT) is an effective treatment for primary diffuse cutaneous lymphomas in humans. While several techniques exist, they all require significant commitment of staff time and resources. In veterinary medicine, canine-specific techniques and strategies have been adapted and delivered but deemed not “realistically” clinically implementable given the time commitment of over 2.5 h plus per fraction or have been relegated to palliative intent. Leveraging these technologies of helical tomotherapy and 3D printing, we developed and clinically implemented a radiotherapeutic treatment strategy for the management of medically refractory diffuse cutaneous lymphoma in the dog.Case presentationA 13.5-year-old female spayed Bichon Frise presented to the Oncology service at Texas A&M University, College of Veterinary Medicine due to the progression of diffuse cutaneous epitheliotropic lymphoma (CEL) that had failed medical management. Twenty-seven gray were delivered to the patient with a treatment time requirement under 40 min including real time monitoring of anesthesia during setup and treatment. A partial response was noticeable after four fractions and the tumor completely regressed progressively over the entire treated area by the end of therapy. A grade 1 lethargy, fatigue, weight loss, and oral mucositis and grade 2 alopecia, nail/claw changes, pruritus, scaling, anorexia, and diarrhea were noted during treatment. Additionally, a grade 3 thrombocytopenia developed after fraction eight requiring a treatment interruption of 6 weeks and prescription modification prior to treatment continuation and completion. From the beginning of total skin photon radiation therapy (TSPT) treatment until the time of the patient was euthanized unrelated to cutaneous epitheliotropic lymphoma (123 days), only one new lesion on the head was identified and confirmed by histopathology within the treated fields.ConclusionsThe proposed technique is an acceptable alternative to TSEBT that is actually clinically implementable within a palliative or definitive setting and clinical constraints, however further testing and refinement is needed to reduce hematological complications and to confirm and expand on preliminary findings.

Treatment of indolent cutaneous T‐cell lymphoma with hypofractionated radiation therapy in three cats

“…Lymphoma is known typically to be sensitive to radiotherapy, with lymphocyte apoptosis as well as an antitumour immune response observed at the site of radiation. 6,7 Lymphocytic infiltration markedly improved in cases 1 and 2 after radiation therapy. Additionally, all cats showed gross clinical improvement defined by hair regrowth and a partial response or complete resolution of cutaneous lesions.…”

“…5,6 In veterinary medicine, RT was used in a case of canine progressive diffuse cutaneous epitheliotropic lymphoma that had failed medical management with complete regression of the lesions. 7 The case series reported here describes the treatment of ICL with hypofractionated RT in three cats.…”

Investigation of total skin helical tomotherapy using a 3D-printed total skin bolus

“…Electron therapy, which does not require a bolus, is an alternative method for increasing the skin dose. Deveau et al [ 9 ] used 3D printing technology to investigate the effect of changing the bolus on increasing skin dose in TSHT. Specifically, they created a total skin bolus for a dog using 3D printing technology.…”