Dear Editor,

The paper “Conventional laparoscopic segmental bowel resection with mini-laparotomy specimen extraction compared with Natural Orifice Specimen Extraction (NOSE) procedures in patients with colorectal endometriosis” by Popov et al.¹ caught our attention. The authors deserve praise for tackling a significant and clinically difficult facet of managing colorectal endometriosis. The study provides important information about the safety, effectiveness, postoperative results, and quality of life related to various surgical techniques by contrasting the new NOSE technique with the traditional laparoscopic approach. Additionally, adding patient-centered outcomes like pain scores and KESS quality-of-life evaluations improves the data therapeutic relevance and gives surgeons managing deep infiltrating endometriosis helpful information.

While acknowledging these significant advantages and the work’s contribution to the current conversation about the best way to treat colorectal endometriosis, we would want to draw attention to a few methodological issues with the study.

First, the retrospective design inherently limits causal inference and increases susceptibility to selection bias.² More importantly, the conventional laparoscopic surgery (CLS) cohort and NOSE cohort were not treated contemporaneously. The authors reported that CLS was routinely performed between 2015-2020, whereas NOSE was introduced later as an alternative technique. Such temporal separation raises the possibility of historical and proficiency bias, as improvements in surgical expertise, perioperative care pathways, and institutional experience over time may independently affect outcomes.³ Therefore, observed similarities or differences may partly reflect evolution in practice rather than the surgical technique itself.

Second, a number of potentially significant confounding factors, such as lesion complexity, disease severity, prior surgical history, and concomitant pelvic involvement, were not taken into account even though baseline data including age, body mass index, and symptom levels were compared. Additionally, neither multivariable regression analysis nor propensity score matching were used to reduce baseline imbalance across groups. Thus, residual confusion is still a possibility.⁴

Despite these considerations, we commend the authors for their valuable contribution to the growing body of literature on surgical management of colorectal endometriosis. Their study provides important insights into the feasibility and safety of NOSE techniques and highlights an evolving area of minimally invasive surgery. We appreciate the authors’ efforts in addressing this clinically relevant topic and believe their findings will stimulate further research. We concur that larger prospective, multicenter randomized studies are warranted to further clarify the comparative effectiveness and long-term outcomes of these surgical approaches.