{'fraction_non_alphanumeric': 0.02681992337164751, 'fraction_numerical': 0.009431181844974948, 'mean_word_length': 5.060714285714286, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 1, 'zh_pornsignals.json': 0}}
Is the never-ending story still unsolved? Beyond the long debate about lateral pelvic LN dissection in rectal cancer.

The ultimate goals of the surgical treatment of locally advanced rectal cancer are the complete removal of the primary tumor without any residual tumor tissue and the preservation of the anal sphincter and urogenital function. The required extent of surgery, that is, total mesorectal excision (TME) or TME plus lateral pelvic lymph node (LPLN) dissection, has been the subject of a long-standing debate between West and East. Now, before we could conclude this debate, more issues have arisen: Is lateral pelvic lymph node dissection (LPLD) after neoadjuvant chemoradiotherapy (CRT) necessary? If the answer is yes, what is the optimal indication for LPLD after CRT in locally advanced rectal cancer? In Japan, lateral pelvic lymph node metastasis (LPLM) has been considered a regional disease, and TME and LPLD without CRT are accepted as the standard treatment.1 In the West, LPLM has been regarded as a systemic disease in patients with a generally higher BMI, making LPLD difficult to perform in a narrow space. Consequently, surgeons have focused on clear resection margins and developed neoadjuvant CRT as the optimal approach.2 Preoperative CRT followed by TME has become the standard treatment, and debates on the oncological benefits of LPLD in locally advanced mid-to-low rectal cancer have remained controversial in the West. Georgiou et al3 performed a meta-analysis to compare extended lymphadenectomy (TME with LPLD) with TME alone. They found no overall differences in cancer-specific outcomes, but LPLD was associated with longer operative times, greater intraoperative blood loss, and a higher incidence of urinary and sexual dysfunction than TME alone. Meanwhile, a multicenter randomized controlled trial (JCOG 0212) established that prophylactic LPLD significantly reduced the rate of local recurrence compared with TME alone (7.4% vs 12.6%) without a significant increase in severe postoperative complications.4 Kusters et al5 compared the oncological outcomes of low rectal cancer treatment between Japan and the Netherlands and reported a 5-year local recurrence rate of 6.9% in the Japanese TMEwith-LPLD group and 5.8% in the Dutch TME-with-CRT group, with recurrence rates in the lateral pelvis of 2.2% and 2.7%. These results suggest that neoadjuvant CRT and LPLD result in similar local oncological outcomes. A Eastern study reported that a major portion of local recurrence patterns consisted of recurrence in the lateral pelvic wall, and that enlarged LPLN on pre-CRT imaging was associated with an incidence of lateral recurrence in patients who underwent TME and CRT without LPLD.6 Recently, a multinational, multicenter study reported that the 5-year lateral pelvic wall recurrence rate was 19.5% in patients with an LPLN size ≥7 mm on preoperative MRI who were treated with TME plus LPLD only, but that the addition of selective LPLD could significantly reduce the rate to 5.7%.7 These studies suggest that TME after CRT may be insufficient in patients with enlarged LPLN and that selective LPLD may reduce local recurrence in this group. In the era of the great East-West debate on the treatment of locally advanced rectal cancer, especially when focusing on the lateral pelvic wall, surgeons in both worlds Funding/Support: None reported.