The “Triangle Operation” In Pancreatic Cancer: Toward Optimizing Oncological Radicality After Neoadjuvant Therapy

Review Article

The “Triangle Operation” In Pancreatic Cancer: Toward Optimizing Oncological Radicality After Neoadjuvant Therapy

Dr Menoura R ^1*
Dr Tibermacine W ²
Dr Rais B ¹
Dr Aoun Allah I ³
Dr Bouceneche L ³
Delmi A ¹

1 Surgery B department Constantine university hospital, Algeria.

2 Radiology department Constantine university hospital, Algeria.

3 Oncology department Didouche Mourad Hospital, Constantine, Algeria.

*Corresponding Author: Dr Menoura R,Surgery B department Constantine university hospital, Algeria.

Citation: Menoura R, Tibermacine W, Rais B, Allah A, Bouceneche L, et al., (2026). The “Triangle Operation” In Pancreatic Cancer: Toward Optimizing Oncological Radicality After Neoadjuvant Therapy. International Journal of Medical Case Reports and Reviews, BioRes Scientia Publishers. 6(1):1-3. DOI: 10.59657/2837-8172.brs.26.089

Copyright: © 2026 Menoura R, this is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Received: April 18, 2026 | Accepted: May 01, 2026 | Published: June 02, 2026

Abstract

Recent advances in pancreatic cancer management, particularly with the introduction of intensive neoadjuvant chemotherapy regimens, have significantly reshaped surgical indications and objectives. In this context, the “Triangle Operation,” described by Thomas Hackert, has emerged as an innovative approach aimed at improving R0 resection rates without systematically resorting to arterial resections. This technique is based on an extensive dissection of the peri-arterial compartment located between the superior mesenteric artery, the celiac trunk, and the porto-mesenteric axis. Its primary goal is to eradicate areas of potential microscopic tumor spread, particularly after neoadjuvant therapy. Through a detailed analysis of anatomical foundations, technical principles, and clinical outcomes, this article highlights both the benefits and limitations of this strategy in the management of borderline resectable and locally advanced pancreatic tumors.

Keywords: superior mesenteric artery; superior mesenteric vein; celiac trunk; mesopancreas; retroportal lamina; unresectable adenocarcinoma

Introduction

Pancreatic cancer remains one of the most aggressive solid malignancies, with a five-year overall survival rate below 10% in most contemporary series, largely due to late diagnosis and a strong tendency for both locoregional and systemic spread [1,2]. Surgery remains the only potentially curative treatment; however, it is limited by a high rate of positive resection margins, particularly at the retroportal margin and around peri-arterial structures [3,4]. The introduction of neoadjuvant chemotherapy protocols, especially FOLFIRINOX and gemcitabine-based combinations, has increased the number of patients eligible for secondary resection by reducing tumor burden and enabling better biological selection [5–7]. However, after neoadjuvant therapy, evaluating tumor–vascular relationships remain challenging due to persistent dense fibrosis, making it difficult to distinguish residual viable tumor from post-treatment scarring [8,9]. In this setting, the need for systematic arterial resection has been questioned, given the significant morbidity associated with such procedures [10]. The “Triangle Operation” was therefore developed to achieve maximal oncological radicality through extensive peri-arterial dissection without arterial reconstruction [11,12].

Anatomical Basis and Oncological Rationale

Tumor spread in pancreatic cancer preferentially occurs along neural sheaths and vascular structures, particularly around the superior mesenteric artery and the celiac trunk [13,14]. Perineural invasion is observed in more than 70% of cases and represents a major predictor of local recurrence [15]. The anatomical compartment targeted by the “Triangle Operation” corresponds to a three-dimensional space bounded by the superior mesenteric artery, the celiac trunk, and the portal vein. This region includes the retroportal lamina, peri-arterial nerve plexuses, and deep lymphatic pathways, which are the primary sites of positive margins following standard pancreaticoduodenectomy [16–18]. After neoadjuvant therapy, these structures frequently exhibit reactive fibrosis that may conceal residual viable tumor, thereby justifying systematic resection of this compartment to improve local disease control [19,20].

Surgical Technique

The “Triangle Operation” involves a systematic and extensive dissection of the peri-arterial compartment. Following thorough exploration to exclude metastatic disease, the procedure begins with mobilization of the porto-mesenteric axis, followed by complete skeletonization of the superior mesenteric artery and the celiac trunk. This step requires a circumferential 360-degree dissection, allowing en bloc removal of all peri-arterial fibro-neural tissue [11,21]. Pancreatic resection is subsequently performed according to tumor location, either as pancreaticoduodenectomy or distal pancreatectomy. The primary objective is to achieve a negative retroportal margin by removing all tissues at risk of microscopic invasion [22].

Oncological and Clinical Outcomes

Initial series reported by Hackert et al. demonstrated that the “Triangle Operation” could achieve R0 resection rates of up to 80–90% in selected patients following neoadjuvant therapy [11,23]. These findings have been supported by subsequent multicenter studies, which also reported improved overall survival compared with conventional surgical approaches [24,25].In terms of morbidity, this technique does not appear to significantly increase major postoperative complications compared to standard surgery, although functional disorders related to denervation, particularly postoperative diarrhea, are commonly observed [26,27].Furthermore, several studies suggest that this approach reduces the need for arterial resections without compromising oncological outcomes, representing a major advantage in terms of morbidity and mortality [28,29].

Limitations and Controversies

Despite its promising results, the “Triangle Operation” raises several concerns. The main limitation lies in the difficulty of distinguishing post-treatment fibrosis from residual tumor, both preoperatively and intraoperatively, which may lead to incomplete resection [30].

Additionally, this technique is highly dependent on surgical expertise and requires advanced skills in vascular dissection, thereby limiting its application to high-volume specialized centers [31]. The lack of standardization in both technique and indications further restricts its widespread adoption [32].

Finally, patient selection remains critical, as the “Triangle Operation” is primarily indicated in patients demonstrating a favorable response to neoadjuvant chemotherapy without disease progression [33].

Discussion

The “Triangle Operation” represents a major paradigm shift in pancreatic surgery, moving from a purely anatomical approach toward a strategy focused on controlling the tumor microenvironment. It is based on the concept that peri-arterial structures serve as a sanctuary for tumor dissemination and must therefore be systematically resected to improve oncological outcomes [34,35].

This approach is closely linked to advances in medical oncology, particularly neoadjuvant chemotherapy, which enables better patient selection for radical surgery [36,37]. It is thus part of a comprehensive multimodal strategy combining systemic therapy and targeted surgical intervention.

Conclusion

The “Triangle Operation” constitutes a significant advancement in the surgical management of borderline resectable and locally advanced pancreatic cancer. By enabling complete dissection of the peri-arterial compartment, it improves R0 resection rates while avoiding complex arterial reconstruction. However, its indication must remain cautious and restricted to carefully selected patients, and it should be performed in specialized centers with advanced expertise in pancreatic surgery.

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