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Exocrine Pancreatic Cancer
Avenelle I. Turner, DVM, DACVIM (Oncology)

Veterinary Cancer Group, Culver City, CA, USA

Etiology/Pathophysiology History and Clinical Signs

Nearly all cancers of the exocrine pancreas are epithelial Symptoms associated with EPC are nonspecific and may
and most are adenocarcinoma arising from either the mimic pancreatitis. Anorexia, weight loss, lethargy, weak-
ductal or acinar epithelium. This is in contrast to insu- ness, vomiting, maldigestion syndrome, abdominal disten-
linomas which arise from the islet cells of the endocrine sion, abdominal effusion, and icterus are common findings.
pancreas. Insulinomas are covered in more detail in a In cats that presented with EPC, 75% had anorexia, 63%
different section. There are no known causes for exo- vomiting, and 38% abdominal pain, a palpable abdominal
crine pancreatic cancer (EPC) in veterinary medicine. mass, and/or jaundice. Duration of clinical signs appeared
Experimentally, intraductal administration of N‐ethyl‐ to be bimodal, with 50% of cats having signs for <7 days
N’‐nitro‐N‐nitrosoguanidine induces EPC in dogs. and the other 50% having signs for >1 month.
Paraneoplastic alopecia is a rare syndrome seen in cats
with pancreatic neoplasms. The pathogenesis of this der-
Epidemiology matologic disease is unknown. Alopecia begins acutely
and typically starts with loss of clumps of hair on the
Exocrine pancreatic cancer is rare and accounts for less ventrum, and then spreads to the legs and eventually the
than 0.05% of all cancers in the dog and cat. Older female face. Dorsal alopecia is uncommon. Other changes noted
dogs, spaniels, and Airedales have been described in pre- are poor, dry, thinning hair coat and focal areas of
vious publications as being at higher risk. In humans, erythema. Often, there is a characteristic appearance to
EPC remains the fourth most common cause of cancer‐ the skin and in areas where cats groom, the skin can
related death in the United States and it occurs most appear shiny. Lesions develop rapidly over 2–10 weeks
commonly in people who smoke or have chronic pan- and spread over much of the body. They appear in asso-
creatitis or diabetes mellitus. It is not clear if this is true ciation with the tumor and in one case resolved with
in veterinary medicine but recently there have been sev- tumor removal.
eral published reports of diabetes mellitus and EPC in Histopathologically, the skin changes are character-
cats which are suggestive of a possible association. It is ized by loss of the stratum corneum and severe follicular
unknown whether diabetes mellitus develops secondary atrophy with miniaturized hair bulbs. The majority of
to compression of islet cells by tumor, secondary to cor- cases die or are euthanized within eight weeks of devel-
tisol‐induced beta‐cell degeneration, or secondary to opment of lesions so the presence of this condition on
decreased carbohydrate metabolism, which is common physical examination is highly suspicious for EPC and
in humans with pancreatic carcinoma. appears to be a poor prognostic factor.

Signalment Diagnosis

The median age at diagnosis is 10 years for dogs and 12 Staging for EPC includes radiographs of the thorax (three‐
years for cats. It occurs almost equally in both sexes. view), abdominal radiographs (two‐view), minimum

Clinical Small Animal Internal Medicine Volume II, First Edition. Edited by David S. Bruyette.
© 2020 John Wiley & Sons, Inc. Published 2020 by John Wiley & Sons, Inc.
Companion website: www.wiley.com/go/bruyette/clinical