Overview
Definition:
Jejunal gastrointestinal stromal tumors (GISTs) are mesenchymal neoplasms arising from the interstitial cells of Cajal or their precursors within the gastrointestinal tract
Segmental resection involves the surgical removal of a specific segment of the jejunum containing the GIST, along with its mesentery, to achieve negative margins.
Epidemiology:
GISTs are the most common mesenchymal tumors of the GI tract, accounting for less than 1% of all GI tumors
They can occur anywhere along the GI tract, with the stomach (50-60%) and small intestine (20-30%, including jejunum and ileum) being the most common sites
The incidence is approximately 5-20 cases per million per year
They typically occur in adults aged 40-70 years, with no significant gender predilection.
Clinical Significance:
Jejunal GISTs can present with a spectrum of symptoms depending on size and location, ranging from asymptomatic incidentally discovered lesions to life-threatening complications like bleeding or perforation
Understanding the surgical management, particularly segmental resection for localized tumors, is crucial for achieving cure and preventing recurrence
Proper oncological resection is key to patient outcomes, making this a vital topic for surgical trainees preparing for DNB and NEET SS examinations.
Indications
Surgical Indications:
Surgical resection is the primary treatment for resectable GISTs
Indications include: symptomatic tumors (bleeding, obstruction, pain, palpable mass), asymptomatic tumors greater than 5 cm in diameter, tumors with high mitotic activity (≥5 per high-power field), or tumors with features concerning for malignancy (e.g., necrosis, cystic changes, irregular borders) based on imaging
Small, asymptomatic tumors (<2 cm) with low mitotic index may be considered for observation.
Contraindications:
Absolute contraindications are rare for localized GISTs
Relative contraindications may include unresectable disease due to extensive local invasion or distant metastases, or severe comorbidities that make the patient a poor surgical candidate
In such cases, neoadjuvant or adjuvant imatinib therapy might be considered.
Preoperative Assessment:
Preoperative assessment involves thorough history and physical examination, comprehensive laboratory workup (CBC, liver function tests, renal function tests), and detailed imaging
Endoscopic evaluation (EGD, colonoscopy) may be performed if bleeding is suspected or to rule out synchronous GI lesions
Cross-sectional imaging (CT abdomen/pelvis with IV contrast) is essential for staging, evaluating tumor size, location, extent of invasion, lymphadenopathy, and presence of distant metastases
Biopsy is often avoided if the tumor is amenable to en bloc resection due to the risk of tumor seeding and potential for imatinib resistance if inappropriately treated before definitive surgery.
Surgical Management
Approach Selection:
The surgical approach (laparoscopic vs
open) depends on tumor size, location, complexity, surgeon expertise, and patient factors
Laparoscopic resection is preferred for smaller, exophytic tumors with no signs of invasion into adjacent structures, offering benefits of minimally invasive surgery
Open laparotomy is reserved for larger, deeply invasive tumors, or in cases where laparoscopic approach is not feasible.
Procedure Steps:
The goal is en bloc resection with adequate margins
For jejunal GISTs, this typically involves a segmental resection of the jejunum
The procedure includes: 1
Identification and mobilization of the affected jejunal segment
2
Ligation of mesenteric vessels supplying the segment
3
Transection of the jejunum proximal and distal to the tumor with adequate margins (typically 1-2 cm from gross tumor)
4
Excision of the tumor segment with involved mesentery
5
Reconstruction of the jejunal continuity, usually via an end-to-end or side-to-side anastomosis using staplers or sutures
The specimen is then sent for pathological examination
Careful hemostasis and inspection for leaks are paramount.
Margin Assessment:
Pathological assessment of surgical margins is critical
Macroscopic and microscopic evaluation for positive margins (tumor cells at the inked margin) guides further management
Achieving R0 resection (no residual tumor) is the primary goal for cure.
Postoperative Care
Early Postoperative Management:
Patients are monitored in a recovery area for vital signs, pain control, and signs of complications
Nasogastric tube may be used for decompression
Intravenous fluids and electrolytes are managed
Early mobilization and incentive spirometry are encouraged
Pain management is crucial, often using patient-controlled analgesia (PCA) or epidural anesthesia.
Dietary Advancement:
Diet is advanced cautiously starting with clear liquids once bowel sounds return and flatus is passed, progressing to a soft diet as tolerated
Monitoring for signs of anastomotic leak (e.g., abdominal distension, fever, peritonitis) is essential during this period.
Monitoring And Discharge:
Patients are monitored for wound complications, signs of infection, and anastomotic leaks
Serial abdominal examinations are performed
Discharge planning includes wound care instructions, pain management, dietary recommendations, and follow-up appointment scheduling
Patients are advised to avoid strenuous activity for several weeks.
Complications
Early Complications:
Potential early complications include: anastomotic leak (most serious, presenting with peritonitis, sepsis), intra-abdominal abscess, bleeding (anastomotic or mesenteric), ileus, wound infection, hernia, and deep vein thrombosis (DVT) or pulmonary embolism (PE).
Late Complications:
Late complications can include: adhesive small bowel obstruction, incisional hernia, stricture formation at the anastomosis, and tumor recurrence.
Prevention Strategies:
Preventing complications involves meticulous surgical technique (careful tissue handling, secure hemostasis, leak-free anastomosis), appropriate antibiotic prophylaxis, early mobilization, judicious use of anticoagulation for DVT prophylaxis, and thorough preoperative assessment and postoperative monitoring.
Prognosis
Prognostic Factors:
Prognosis is primarily determined by tumor size, mitotic index, location, and the presence of distant metastases at diagnosis
Genetic mutations (e.g., KIT, PDGFRA) also play a role
Complete surgical resection (R0) significantly improves survival.
Outcomes:
For localized, completely resected GISTs, the 5-year survival rate can be as high as 50-80% or more, depending on risk stratification
Unresectable or metastatic GISTs have a poorer prognosis, but response to tyrosine kinase inhibitors like imatinib can significantly improve outcomes.
Follow Up:
Postoperative follow-up is crucial for monitoring for recurrence and for assessing response to adjuvant therapy
This typically involves serial clinical examinations, laboratory tests (including CEA and LDH, though less specific for GIST), and regular cross-sectional imaging (CT abdomen/pelvis, sometimes PET-CT) at intervals (e.g., every 3-6 months for the first 2-3 years, then annually)
Follow-up duration is typically 5-10 years.
Key Points
Exam Focus:
Jejunal GISTs are mesenchymal tumors requiring surgical resection for curative intent
En bloc segmental resection with adequate margins is key
The choice between laparoscopic and open surgery depends on tumor characteristics
Risk stratification based on size, mitotic index, and mutation status guides prognosis and adjuvant therapy decisions.
Clinical Pearls:
Always consider GIST in mesenchymal lesions of the GI tract
Avoid biopsy of potentially resectable GISTs preoperatively unless absolutely necessary
Laparoscopy is feasible for smaller, exophytic lesions
Thorough mesenteric lymph node sampling is not typically required for GISTs, but adequate mesenteric clearance around the tumor is necessary
Postoperative imatinib therapy is indicated for high-risk GISTs.
Common Mistakes:
Inadequate surgical margins leading to positive resection margins and recurrence
Performing a biopsy of a resectable GIST, leading to potential complications or altered treatment planning
Incorrect risk stratification leading to inappropriate adjuvant therapy
Insufficient or irregular postoperative follow-up, missing early signs of recurrence.