Page 5 - Clinical Connections - Autumn 2024

Oncology case study
LONG-TERM SURVIVAL IN A DOG WITH

GASTRIC ADENOCARCINOMA

Vivek Basu (vet and Aria’s owner), Andy Yale (Lecturer in Veterinary Oncology) and Sandra Guillén
(Lecturer in Veterinary Oncology)
ria, an 11-year-old rough collie, having sporadic episodes of abdominal with the combination of marginal tumour
was presented for investigation pain and retching immediately after eating. excision and chemotherapy may have
A into chronic vomiting and weight A repeat ultrasound of the abdomen contributed to it.
loss. Aria had a history of hypothyroidism, showed segmental wall thickening of In a recent study of dogs undergoing
which was well controlled. Haematology the small curvature and associated partial gastrectomy +/- chemotherapy,
and biochemistry on admission were largely pancreatoduodenal and cranial mesenteric the median survival time was 178 days
unremarkable. Total thyroxine, cobalamin, lymphadenopathy. and administration of chemotherapy was
folate, and ACTH stimulation tests were also These findings, together with the clinical associated with improved survival, but only
within normal limits. signs, were most compatible with tumour 7 out of 40 dogs had a survival of more than
Abdominal ultrasound showed gastric recurrence. Aria was then started on 10 months.
wall thickening in the region of the fundus rescue chemotherapy with intravenous 5- Of those long-term survivors, four received
and greater curvature of the stomach. fluorouracil every two weeks. Multimodal carboplatin based protocols, with two of
Gastroduodenoscopy revealed a focal analgesia was also started, with robenacoxib them also receiving toceranib afterwards.
erythematous lesion in the fundus. once a day, paracetamol twice a day, and One dog was treated with toceranib only
Endoscopic biopsies were obtained, and gabapentin twice a day. and one dog with mitoxantrone.
histopathology was suggestive of early Sadly, Aria continued to experience Aria underwent three different
gastric adenocarcinoma. weight loss and abdominal pain despite chemotherapy and molecular targeted
CT of the thorax and abdomen showed multimodal analgesia, and humane therapy protocols, with carboplatin appearing
no evidence of metastases and following euthanasia was performed 12 months after to make the most significant improvement in
discussion with our Soft Tissue Surgery her initial presentation. quality of life. More importantly, her adverse
Service and her carer, Vivek, who is a vet, reactions were expected, mild, and well
Aria underwent a partial gastrectomy. Case discussion managed on an outpatient basis.
Histopathology confirmed an Gastric carcinomas (GC) account for less Toceranib has been anecdotally used in
undifferentiated adenocarcinoma, with than 1% of all canine tumours, although dogs with GC based on the overexpression of
vascular and serosal invasion, which had represents one of the most common tumours receptor tyrosine kinases, its antiangiogenic
been incompletely excised. found in this location in dogs, followed by properties, and the responses seen with a
Aria’s vomiting and appetite improved leiomyo(sarco)ma, gastrointestinal stromal similar drug (sorafenib) in humans with GC.
after surgery but given the high metastatic tumours and lymphoma. Due to Aria’s higher-than-average
rate reported for this cancer, adjuvant Similar to humans, the aetiology of canine survival time and excellent quality of life, it is
chemotherapy of carboplatin was gastric carcinomas is complex and poorly our hope that this protocol can be adapted
recommended. understood, but it is believed that both for future similar situations and allow those
Aria continued to have an excellent environmental and genetic factors play a animals to experience a similar outcome.
quality of life throughout chemotherapy, with role. Unfortunately, diagnosis is often made
only mild side effects seen. After finishing when the disease is at an advanced stage
the six-dose carboplatin protocol, ongoing and metastatic disease can be found in up
maintenance treatment with toceranib to 70% of dogs.
phosphate was elected. However, due to Limited information is available regarding
recurrent diarrhoea this was discontinued the clinical outcome of GC after surgical
after nine weeks. resection, as well as chemotherapy’s role
in the progression of this disease. In Aria’s
Nine months on case, the long survival time was unusual,
At nine months post-diagnosis, Aria started but we believe that the multimodal approach Vivek's note: Aria is my own dog, she
carried me throughout vet school and
Sagittal CT scan image showing moderate thickening of the gastric fundus (arrow) and no
evidence of metastases my career, traveling the globe alongside
me. She meant more than words can
express, and I hope this case study
can be her legacy, helping future
generations and continuing to improve
the world alongside the joy she brought
to everyone that knew her.

For small animal referrals, please call:
01707 666399
Email:
qmhreception@rvc.ac.uk

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