Organ preservation with local excision and indocyanine green fluorescence imaging guided video endoscopic inguinal lymphadenectomy for rectal cancer with bilateral inguinal lymph node metastasis-a video vignette

Inguinal lymph node metastasis (ILNM) is rare among rectal cancer patients (1.2%–2.4%) and is associated with a poor prognosis [1-3]. Inguinal lymphadenectomy is an important part of treatment for rectal cancer with ILNM [4]. Traditional open inguinal lymphadenectomy is usually limited due to high probability of postoperative complications [5, 6]. Recently, video endoscopic inguinal lymphadenectomy (VEIL) has been increasingly utilized to minimize surgical morbidities without compromising oncological outcomes in urological and gynaecological surgeries [7]. However, VEIL has seldom been reported in the treatment for rectal cancer [8, 9]. Intra-operative near-infrared (NIR) fluorescence imaging with indocyanine green (ICG) can help improve the accuracy and completeness of lymphadenectomy in colorectal cancer surgery [10, 11]. Nevertheless, NIR/ICG imaging has rarely been utilized during VEIL for rectal cancer with ILNM. The role of ICG to guide inguinal nodal dissection remains to be defined. Besides, an organ-preserving strategy with local excision seems to be a diagnostic and therapeutic option in carefully selected rectal cancer patients who respond well to chemoradiotherapy, especially in those who are unfit or reluctant for radical surgery [12]. However, such a treatment strategy has rarely been reported in rectal cancer patients with ILNM. In Video S1, we present an application of organ preservation with local excision and NIR/ICG fluorescence imaging guided VEIL for rectal cancer with bilateral ILNM. A 54-year-old man was diagnosed with rectal cancer with bilateral ILNM (staged cT3N2M1a). After multidisciplinary team discussion, the patient received long-course radiation (total dose of 50.4 Gy in 28 fractions) to the entire pelvis and bilateral inguinal regions followed by 12 courses of mFOLFOX6 (modified regimen of leucovorin, fluorouracil and oxaliplatin) chemotherapy and cetuximab targeted therapy. Both MR and positron emission tomography/CT scans revealed that the primary tumour responded significantly to chemoradiotherapy, but not the bilateral inguinal lymph nodes (LNs) (staged ycT0-1N0M1a). After multidisciplinary team discussion, the patient underwent organ preservation with transanal local excision and NIR/ICG-imaging-guided bilateral VEIL. Two millilitres of ICG dye was injected submucosally around the tumour transanally 1 day before surgery. Local excision was performed using conventional transanal excision. The patient was placed in a lithotomy position. A tumour scar was found 2 cm above the anal verge on the posterior wall of the rectum. To ensure a maximal radial margin, full-thickness excision was performed using regular electrocautery 1 cm laterally around the residual tumour scar. The rectal defect was closed with a continuous 3/0 Vicryl suture. The excised specimen was then fixed on cardboard, marked for orientation by the surgeon and sent for pathological examination. Following local excision, the patient was placed in a supine position with thigh abduction. First, a 1.5 cm incision was made 2 cm below the lower vertex of the femoral triangle. The right-sided NIR/ICG-guided VEIL was performed on 3 ports. A working space superficial to the Scarpa's fascia was created by scissors and digital manoeuvres and then insufflated with CO2 at 12 mmHg. To provide traction, the assistant grabbed the skin and lifted it. Lymphadenectomy boundaries were inferior to the apex of the femoral triangle, medially by the adductor longus muscle, and laterally by the sartorius muscle. Then, the superficial inguinal LNs were separated from the Scarpa's fascia, while the saphenous vein was spared. Deep inguinal LN dissection was then carried out inferomedially around the femoral vein, starting at the transected saphenofemoral junction. The NIR/ICG fluorescence imaging confirmed the absence of unresected residual inguinal LNs. Finally, the resected LNs were retrieved into a specimen bag through a 10 mm trocar, and a drain tube was placed through a 5 mm trocar. Next, the left-sided NIR/ICG-guided VEIL was also performed. The superficial inguinal LNs were not visible under NIR/ICG imaging, mainly due to the obstruction of the lymphatic duct following the previous inguinal LN biopsy. The superficial inguinal LNs were removed from the Scarpa's fascia. After the identification of the femoral artery and vein, the deep inguinal LNs were dissected. Finally, the resected LNs were packed and extracted. The operating time was 180 min, and the estimated blood loss was 20 ml. The postoperative pathology revealed a residual rectal cancer showing extensive tumour regression (<1% viable tumour identified). However, there were 3 metastatic LNs out of 10 resected right superficial inguinal LNs and 2 metastatic LNs out of 8 resected left superficial inguinal LNs. The patient was discharged on the eighth postoperative day without any complications. The latest 12-month follow-up showed no evidence of tumour relapse both locally (e.g., primary tumour site, pelvic lateral and inguinal regions) and distally (e.g., liver, lung, bone and brain etc.).To conclude, NIR/ICG imaging has the potential to guide VEIL in rectal cancer surgery. The oncological efficacy needs to be addressed in future studies. The authors thank all the Department of Colorectal Surgery staff of Fujian Medical University Union Hospital (FMUUH, Fuzhou, China). None. None declared. This study was approved by the institional review board of the Fujian Medical University Union Hospital. Video S1. 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