Overview
Definition:
Lateral pelvic lymph node dissection (LPLND) is a surgical procedure involving the removal of lymph nodes located along the iliac vessels, obturator fossa, and sacral areas, primarily performed in the management of advanced gynecologic malignancies with suspected or confirmed pelvic lymph node metastasis
It aims to achieve accurate staging and regional control of the disease.
Epidemiology:
Pelvic lymph node metastasis is a significant prognostic factor in gynecologic cancers
Incidence varies by primary tumor type and stage
For example, clinically apparent pelvic lymphadenopathy is seen in approximately 5-15% of early-stage cervical cancers and a higher percentage of advanced stages
LPLND is considered in situations where sentinel lymph node biopsy is not feasible or has proven positive.
Clinical Significance:
Accurate assessment of pelvic lymph node status is critical for optimal treatment planning and prognostication in gynecologic cancers
LPLND provides definitive pathological information, guiding adjuvant therapy decisions such as radiation and chemotherapy
It is essential for achieving local-regional control and potentially improving survival outcomes in patients with nodal disease.
Indications
Primary Indications:
Advanced cervical cancer (FIGO stage IIB-IVA)
Advanced vaginal cancer
Advanced vulvar cancer with suspicious or confirmed pelvic nodal involvement
Recurrent gynecologic malignancies with pelvic nodal disease
Positive sentinel lymph node biopsy in select cases of advanced disease.
Contraindications:
Extensive distant metastasis
Unresectable primary tumor
Severe medical comorbidities precluding major surgery
Previous extensive pelvic radiation therapy that may render dissection technically difficult and increase complication risks.
Staging Considerations:
LPLND is often performed as part of a comprehensive surgical staging procedure, including hysterectomy, bilateral salpingo-oophorectomy, and potentially para-aortic lymphadenectomy, depending on the primary cancer and risk factors.
Preoperative Preparation
Patient Evaluation:
Thorough medical history, physical examination, and assessment of comorbidities
Imaging studies (CT, MRI, PET-CT) to evaluate tumor extent and nodal status
Laboratory investigations including complete blood count, coagulation profile, renal and liver function tests
Counseling regarding surgical risks, benefits, and potential complications.
Surgical Planning:
Selection of appropriate surgical approach (open, minimally invasive - laparoscopic or robotic)
Identification of critical structures to be preserved or identified (ureters, iliac vessels, nerves)
Preoperative antibiotics and venous thromboembolism prophylaxis.
Bowel Preparation:
Routine bowel preparation may be employed to reduce the risk of intraoperative contamination, though its necessity is debated and often individualized based on surgeon preference and patient factors.
Procedure Steps
Surgical Approach:
Open laparotomy is the traditional approach
Minimally invasive techniques (laparoscopic or robotic surgery) offer potential benefits like reduced blood loss, shorter hospital stays, and faster recovery, but require specialized expertise.
Lymph Node Compartments:
Dissection typically includes lymph nodes in the common iliac, external iliac, internal iliac (hypogastric), obturator, and presacral spaces
The extent of dissection is tailored to the primary cancer and risk of metastasis.
Dissection Technique:
Careful identification and preservation of vital structures such as the ureters, bladder, pelvic nerves, and major blood vessels
Lymph nodes are dissected en bloc with surrounding fatty tissue
Hemostasis is meticulously achieved
Specimens are oriented and sent for pathological examination.
Closure:
Closure of surgical planes and abdominal wall layers
Placement of drains may be considered based on the extent of dissection and surgeon preference.
Postoperative Care
Pain Management:
Adequate analgesia is crucial, often involving patient-controlled analgesia (PCA), epidural anesthesia, or multimodal oral analgesics
Early mobilization is encouraged.
Monitoring:
Close monitoring of vital signs, urine output, and fluid balance
Assessment for signs of infection, bleeding, or lymphatic leak (chylous ascites).
Mobility And Rehabilitation:
Early ambulation to prevent deep vein thrombosis and pulmonary complications
Gradual return to normal diet and activity levels
Physiotherapy may be beneficial.
Lymphocoele Management:
Observation for lymphocoeles, which may resolve spontaneously or require percutaneous drainage or surgical marsupialization if symptomatic.
Complications
Early Complications:
Hemorrhage, infection (wound, pelvic abscess), injury to pelvic organs or vessels, deep vein thrombosis, pulmonary embolism, acute kidney injury, ileus, nerve injury (e.g., femoral nerve neuropathy causing leg weakness or paresthesia).
Late Complications:
Lymphedema of the lower extremities or vulva, chronic pain syndromes, lymphocoele formation, radiation-induced complications if adjuvant radiation is given following LPLND.
Prevention Strategies:
Meticulous surgical technique, careful identification of structures, adequate hemostasis, appropriate antibiotic prophylaxis, early mobilization, judicious use of drains, and patient education on self-care for lymphedema.
Prognosis
Factors Affecting Prognosis:
Number and location of positive lymph nodes, extranodal extension, stage of the primary tumor, histological grade, and presence of distant metastasis
Patients with negative pelvic lymph nodes generally have a better prognosis.
Outcomes:
For patients with pelvic lymph node metastasis, LPLND helps in risk stratification, guiding adjuvant therapy and influencing survival
The presence of metastatic pelvic nodes is a strong predictor of poorer survival, but successful treatment can still offer a chance of cure or long-term remission.
Follow Up:
Regular follow-up appointments with clinical examination and imaging as per institutional protocols are essential to monitor for recurrence and manage long-term sequelae such as lymphedema.
Key Points
Exam Focus:
Understand the indications for LPLND in gynecologic cancers
Differentiate between superficial and deep pelvic lymph node compartments
Recognize critical structures during dissection
Identify common complications and their management.
Clinical Pearls:
In difficult dissections, consider intraoperative imaging or nerve stimulation
Meticulous hemostasis is paramount to minimize postoperative hematoma and infection
Early recognition and management of lymphedema are crucial.
Common Mistakes:
Incomplete nodal dissection due to anatomical difficulty or fear of injuring structures
Failure to identify or manage lymphocoeles
Overlooking extranodal extension on pathology
Inadequate adjuvant therapy based on accurate nodal staging.