Unraveling the Interplay of KRAS, NRAS, BRAF, and Micro-Satellite Instability in Non-Metastatic Colon Cancer: A Systematic Review.

Microsatellite Instability (MSI-H) occurs in approximately 15% of non-metastatic colon cancers, influencing patient outcomes positively compared to microsatellite stable (MSS) cancers. This systematic review focuses on the prognostic significance of KRAS, NRAS, and BRAF mutations within MSI-H colon cancer. Through comprehensive searches in databases like MEDLINE, EMBASE, and others until 1 January 2024, we selected 8 pertinent studies from an initial pool of 1918. These studies, encompassing nine trials and five observational studies involving 13,273 patients, provided insights into disease-free survival (DFS), survival after recurrence, and overall survival. The pooled data suggest that while KRAS and BRAF mutations typically predict poorer outcomes in MSS colorectal cancer, their impact is less pronounced in MSI contexts, with implications varying across different stages of cancer and treatment responses. In particular, adverse effects of these mutations manifest significantly upon recurrence rather than affecting immediate DFS. Our findings confirm the complex interplay between genetic mutations and MSI status, emphasizing the nuanced role of MSI in modifying the prognostic implications of KRAS, NRAS, and BRAF mutations in colon cancer. This review underscores the importance of considering MSI alongside mutational status in the clinical decision-making process, aiming to tailor therapeutic strategies more effectively for colon cancer patients.

Redo surgery after low anterior resection for chronic pelvic sinus and anastomotic disruption. Could pull-through procedure with delayed anastomosis be a feasible alternative? Case reports and narrative review.

INTRODUCTION: A considerable step forward in low rectal cancer resection has been done in the last decades. Maintaining total mesorectal excision as the gold standard treatment, new techniques such as Trans-Anal Mini-Invasive Surgery (TAMIS) and Trans-Anal Total Mesorectal Excision (TATME), which have been added to improve skills in laparoscopic and robotic surgery, currently represent the advancement of this procedure. Despite improvements in surgical techniques, complications after low anterior resection for rectal cancer still remain a challenge. Drainage and colostomy are the main treatments used to overcome the problem caused by anastomosis failure, and most patients will never been restored. Different techniques of redo surgery could be proposed to deal complex cases, although remaining high risk procedures. CASE PRESENTATION: We present two clinical cases with a late complication of the colorectal anastomosis: one with a late leakage of low colorectal anastomoses, treated with Hartman procedure, that developed a pelvic chronic sinus; the another one with complete anastomotic disruption after massive suture bleeding; both treated with delayed pull-through anastomosis, according to Turnbull-Cutait technique. We also made a review of relative literature, in order to back our therapeutic iters. DISCUSSION: Both the procedures were carried out satisfactorily, with restoration of intestinal continuity and good anastomotic result. It allows the resolutions of the chronic sepsis caused by the pelvic sinus and maintenance of intestinal continuity with a good Wexner incontinence score. Literary review demonstrated that this procedure still remains undervalued and not widely exploited. CONCLUSION: Delayed pull-through coloanal anastomosis could be considered as a valid option, in order to preserve intestinal continuity in septic or complicated low colorectal anastomosis.

Laparoscopic Resection of Synchronous Liver Metastasis Involving the Left Hepatic Vein and the Common Trunk Bifurcation: A Strategy of Parenchyma-Sparing Resection with Left Sectionectomy and 4a Subsegmentectomy by Arantius Approach.

When colorectal cancer presents with liver metastasis, hepatic resection remains the most important factor in prolonging survival, and new paradigms have been proposed to augment resectability. An adequate liver remnant and vascularisation are the only limits in complex liver resection, and parenchyma-sparing surgery is a strategy for minimising the complications, preserving liver function, and allowing patients to undergo further liver resection. The laparoscopic approach represents a new challenge, especially when lesions are located in the superior or posterior part of the liver. We discuss the case of an 81-year-old patient with a single synchronous liver metastasis involving the left hepatic vein and leaning into the middle hepatic vein at the common trunk, where we performed a simultaneous laparoscopic colonic resection with a left sectionectomy extended to segment 4a. The strategic approach to the Arantius ligament by joining the left and middle hepatic vein allowed us to avoid a major liver hepatectomy, preserve the liver parenchyma, reduce complications, enhance patient recovery, and perform the entire procedure by laparoscopy. Our example suggests that the Arantius approach to the left hepatic vein and the common trunk could be a feasible approach to consider in laparoscopic surgery for lesions located in their proximity.

Achieving precision surgery in laparoscopic liver resection with the aid of preoperative three-dimensional reconstruction: A case report.

INTRODUCTION: The use of three-dimensional image reconstruction in liver surgery is well-known and has got many applications: It was first developed for vein reconstruction in liver transplantation and for liver volumetry to prevent post hepatectomy liver failure (PHLF) after major resections. There are many other advantages described in the literature provided by three-dimensional reconstruction, however its diffusion is currently limited. CLINICAL CASE: We present the case of a woman with a single colon cancer metastasis in segment 5 of the liver. Using CT scan images we created a three dimensional reconstruction of the patient's liver and its inners structures. The rendering was used to hypothesize the plan of dissection and to predict the pedicles that needed to be dissected during the procedure. DISCUSSION: We try to demonstrate that, thanks to three dimensional image reconstruction, all the structures that need to be dissected could be effectively located prior to the the surgery with a high grade of approximation. Furthermore the 3D reconstruction could be used as a step by step guide during the whole surgical procedure, showing all the pedicles To be encountered and dissected at every stage. CONCLUSION: 3d reconstruction of the liver is a valid aid in the interpretation of preoperative imaging and intraoperative ultrasound, both for the surgeon and for the entire equipe, facilitating comprehension of patient's liver anatomical features. It allows to predict the location and direction of the pedicles that need to be dissected and resected with high approximation, in order to achieve a more precise and tailored surgery.

The prognostic role of tumor size in patients with gastric cancer.

AIM: The identification of prognostic factors in gastric cancer is important for predicting patients' survival and determining therapeutic strategies. MATERIALS OF STUDY: A retrospective analysis ofpatients who underwent surgery for gastric cancer between 1996 and 2010. The appropriate cut-off value of tumor size related to survival was determined using receiver-operating characteristic (ROC) curves and it was 2,5 cm. Patients were divided into three groups: a small size group (SSG, < 2,5 cm), a medium size group (MSG, between 2,5 and 5 cm) and a large size group (LSG, ≥ 5 cm). RESULTS: Depth of invasion and lymph node metastasis resulted significantly related to tumor size (p < 0.05). Kaplan- Meier survival curves showed that OS rate was significantly higher in SSG patients. The prognosis of patients with tumor size < 2,5 cm was better than patients with tumors ≥ 2.5 cm in size (p < 0.01). DISCUSSION: The tumor size resulted significantly related to OS and it was related to depth of invasion and lymph node metastasis that are themselves prognostic factors. These results confirm and reinforced literature and suggest that at diagnostic pre-operative work-up we can yet define a prognostic value based on tumor size and underline the primary role of complete resection with free surgical margins and D2 lymphadenectomy. CONCLUSION: In patients with gastric cancer tumor size suggests information about the malignancy of the tumor: it is an important predictor of survival and 2,5 cm may be considered as a valid cut-off to define a better or worse prognosis. KEY WORDS: Gastric cancer, Prognosis,Survival, Tumor size.

Intraoperative neuromonitoring in thyroidectomy: the learning curve.

AIM: To evaluate the learning curve in the use of intraoperative neuromonitoring of recurrent laryngeal nerve and vagus in thyroid surgery. MATERIALS OF THE STUDY: We analyzed 140 pts treated consecutively for thyroid disease. All the patients were neuromonitored with Intraoperative neuromonitoring of recurrent laryngeal nerve and vagus. We divided these patients in 7 groups to collect the adverse events during our learning curve. RESULTS: We monitored consecutively 271 nerves. The incidence of transient paralysis was 0.73%.No significant differences were recorded in the groups about the calceium values,the mean operative time. Sensitivity was 100%, specificity 99%, Predictive positive value was 33%, negative predictive value was 100%. DISCUSSION: The recurrent laryngeal nerve injury is the most frequent adverse event in thyroid surgery. The causes of the lesion are different. The introduction of non-invasive monitoring devices that define the standard of IONM in thyroidectomy is increasing in the last period. In our study we performed the neuromonitoring in four times finding several benefits: avoid damage from excessive traction of the thyroid; early identification of RLN extra-laryngeal branches; identification and preservation of the parathyroid glands. CONCLUSION: The use of neuromonitoring in course of thyroidectomy helps the surgeon to early localization, identification, visualization and dissection of the RLN. It is important highlight that for the surgeon, especially the less experienced, the opportunity to immediately verify the absence of nerve structures and the presence of lesions is very important especially in education and research. We confirm that real learning curve requires at least 60 consecutive cases as reported by others in literature. KEY WORDS: Hypocalcaemia, Intraoperative neuromonitoring, Learning curve, Recurrent laryngeal nerve injury, Thyroid surgery.