General Considerations

•leiomyoma is common in very old dogs and is the 2nd most common gastric tumor in dogs

•mean age 15 years with 82% prevalence in 17-18-year-old Beagles

•discrete solitary lesions (usually pedunculated) in the cardia or gastroesophageal junction causing mass effect

•ulceration is uncommon


Clinical Signs

•clinical signs are caused by gastric outflow obstruction, altered motility, or chronic blood loss secondary to tumor necrosis and ulceration

•progressive vomiting is common and may contain fresh or digested blood

•weight loss may be caused by poor digestion, protein malnutrition, or cancer cachexia


Laboratory Tests

•laboratory tests and survey radiographs are usually unrewarding

•leiomyoma and leiomyosarcoma have been associated with paraneoplastic hypoglycemia

•microcytic hypochromic anemia is common with chronic blood loss and occult blood may be detected in feces

•increased liver enzymes may be seen with hepatic metastasis or obstruction of the common bile duct


Imaging


Radiographs

•positive- or double-contrast radiographs: gastric tumors can appear as a mass effect, ulcer crater, delayed gastric emptying with poor motility, and delayed adherence of contrast material to an ulcerated tumor


Ultrasonography

•ultrasonographic findings include transmural thickening of the gastric wall with loss or altered layering (poor echogenic outer and inner lining with hyperechoic central zone)

•other findings include tumor location, ulceration, extension through gastric wall, and lymphadenopathy

•benign lesions tend to be either pedunculated or well circumscribed with gastric leiomyoma commonly located in the cardia


Endoscopy

•gastroscopy allows direct visualization and guided biopsy

•several biopsies should be performed as superficial ulceration, necrosis, and inflammation is common

•submucosal masses are difficult to biopsy and false-negative results are common


Other Imaging Techniques

•CT and MRI



TREATMENT


Surgery


General Considerations

•surgery is recommended for gastric leiomyoma and leiomyosarcoma, but complicated by advanced stage at presentation, frequent metastasis, difficult access, and debilitated animal

•lymph node metastasis is variable and all abdominal lymph node should be evaluated for staging purposes

•curative resection should be attempted if disease is localized to the stomach

•surgical techniques: Billroth I or II or palliative bypass procedures

•Billroth I or II provides immediate relief of gastric outflow obstruction and clinical improvement in early postoperative period

•Billroth II (partial gastrectomy and gastrojejunostomy) or complete gastrectomy (with biliary by-pass) are very extensive surgeries with high morbidity and minimal survival advantage

•partial gastrectomy preferred in humans due to better nutritional status and quality of life and radical gastrectomy does not improve survival time

•palliative gastrojejunostomy for inoperable or metastatic lesions but associated with significant morbidity including anastomotic ulcers


Leiomyoma

•gastrotomy via exploratory ventral midline or lateral intercostal thoracotomy approach

•gastrotomy and submucosal resection recommended with minimal risk of contamination, hemorrhage, or stricture, and good tumor control


Chemotherapy

•no known effective chemotherapy agents for gastric leiomyosarcoma


Prognosis

•prognosis depends on surgical excision, tumor type and grade, and presence of metastatic lesions

•gastric leiomyosarcoma: MST 12.0-21.3 months, with 1-year survival rate 75% and 2-year survival rate 66%

•54% metastatic rate, but metastasis is not a poor prognostic factor with a MST 21.7 months

•leiomyoma an excellent prognosis following surgical resection

SURGICAL ONCOLOGY

SOCIETY

RESEARCH

EDUCATION

LINKS

EMPLOYMENT

 IMAGE LIBRARYImages.html
● HistoryHistory.html
● What is a Surgical OncologistSurgical_Oncology_1.html
● Find a Surgical OncologistSurgical_Oncology_2.html
● Aims and ObjectivesAims.html
● MembershipMembership.html
● CommitteesCommittees.html
● NewsletterNewsletter.html
● Constitution and BylawsConstitution.html
● Research TrialsResearch_Trials.html
● Publications by MembersPublications.html
● Research OpportunitiesResearch_Opportunities.html
● Cancer InformationCancer_Information_1.html
● Conferences and MeetingsConferences.html
● Radiation FacilitiesRadiation_Facilities.html
● CE OpportunitiesCE_Opportunities.html
● Cancer InformationCancer_Information_2.html
● Current OpportunitiesEmployment_Opportunities.html
● Fellowship Training GuidelinesFellowship_Guidelines.html

GASTRIC LEIOMYOMA AND LEIOMYOSARCOMA

● Surgical Oncology JournalsJournals.html
● Surgical Oncology SocietiesSocieties.html
● Veterinary Surgery CollegesColleges.html