Information about GIST by Dr Dhaval Mangukiya. Details of Epidemiology, Classification and Molecular genesis, Prognostic factors, Diagnosis, Management, Followup. https://drdhavalmangukiya.com/ http://www.youtube.com/c/DrDhavalMangukiyaGastrosurgeonSurat https://gastrosurgerysurat.blogspot.com/

1. GIST
Dr DHAVAL MANGUKIYA
Surgical Gastroenterologist
SIDS Hospital

2. • Epidemiology
• Classification and Molecular genesis
• Prognostic factors
• Diagnosis
• Management
• Followup

3. Stromal or mesenchymal neoplasms affecting
the gastrointestinal (GI) tract typically present
as subepithelial neoplasm

4. EPIDEMIOLOGY
• Most common nonepithelial benign neoplasm
involving the GI
• 1 percent of primary GI cancers
• Predominantly in middle-aged and older
individuals
• Familial GIST (5%)
– Neurofibromatosis type 1 (NF1)
– Carney-Stratakis syndrome
– Primary familial GIST syndrome

5. CLASSIFICATION AND MOLECULAR
PATHOGENESIS
• KIT mutations (80%)
• PDGFR alpha mutations (4-5%)
• Wild-type GISTs (10-15%)
• Cellular origin - interstitial cells of Cajal (ICC)

6. PROGNOSTIC DETERMINANTS
• Tumor TNM staging system
• Tumor rupture
• Significance of tumor genotype and kinase
mutation status
• size, mitotic rate, and location

7. CLINICAL MANIFESTATIONS
• Overt GI bleeding – 40 percent
• Abdominal mass – 40 percent
• Abdominal pain – 20 percent

8. DIAGNOSIS
• CT and MRI scanning
• Upper GI endoscopy
• Biopsy
• Endoscopic ultrasonography
• PET scan

10. MANAGEMENT
• All GISTs ≥2 cm in size should be resected.
• Surgical resection is the treatment of choice
for potentially resectable tumors;
• therapy with imatinib may be preferred if a
tumor is borderline resectable, or if resection
would necessitate extensive organ disruption
• The goal of surgical treatment is complete
gross resection with an intact pseudocapsule,
if possible.

11. MANAGEMENT
• Segmental resection of the stomach or intestine
should be performed with the goal of achieving
negative resection margins
• Wider resection of uninvolved tissue is of no
additional benefit.
• Routine lymphadenectomy is unnecessary
because nodal metastases are rare.
• The tumor should be handled carefully to avoid
rupture, which markedly increases the risk of a
disease recurrence.

12. MANAGEMENT
• Selected patients with unresectable
metastatic GIST may also be considered for
resection. Aggressive cytoreductive surgery
should be offered only to patients whose
disease is stable or responding to TKI therapy,
or who have only focal progression. Patients
with extensive disease progression while on
TKI therapy gain little benefit from surgery,
and it should not be pursued.

16. ROLE OF SURGERY IN PATIENTS WITH
METASTATIC DISEASE
• Hepatic resection for liver metastases
• Hepatic arterial embolization and
chemoembolization
• Radiofrequency ablation

17. POSTTREATMENT FOLLOW-UP
• Completely resected GIST tumor - three to six months for five years
• Locally advanced or metastatic disease who are receiving imatinib -
CT scan are recommended every three to six months.
• Small low-risk tumors - CT or MRI every 6 to 12 months for five
years.
• Very low-risk GISTs - not warrant routine follow-up
• Adjuvant treatment with a TKI (imatinib 400 mg daily) for a
minimum of three years in patients who have a completely resected
primary high-risk GIST
• For patients undergoing neoadjuvant imatinib, continue imatinib
postoperatively to complete a total of at least three years of
imatinib therapy

19. Thank You