Surgery for Gastrointestinal Stromal Tumors: State of the Art of Laparoscopic Resection and Surgery for M1 Tumors

Molecular landscape and clinical significance of exon 11 mutations in KIT gene among patients with gastrointestinal stromal tumor: a retrospective exploratory study

Objective

This aim of this study was to investigate the prognostic significance of KIT exon 11 mutation subtypes in patients with GISTs.

Methods

A total of 233 consecutive patients diagnosed with GISTs at the First Affiliated Hospital of Zhengzhou University from January 2013 to August 2018 were included in this study. The prevalence and mutation landscape of exon 11 in KIT was presented. The clinicopathological characteristics and prognosis among the different mutation subtypes were analyzed. All the statistical analyses were performed by SPSS22.0.

Results

Somatic mutational analysis indicated that point mutations were the most frequently detected mutations followed by deletions & compound mutations and insertion and tandem duplication mutations in the stomach. Point mutations showed a low mitotic count and a high risk of recurrence, and deletions and compound mutations have a high mitotic count while insertions and tandem duplication mutations showed a low mitotic count with an intermediate recurrence risk. Point mutations and deletions frequently occurred in sequence region codons 550-560 of exon 11, while compound mutations, insertion, and tandem duplication were mainly detected in codons 557-559, 572-580, and 577-581, respectively. The multi-variation analysis demonstrated that tumor diameter and high recurrence risk groups had worse prognostic values. However, mutation types were not significant predictors of relapse-free survival (RFS) in GISTs. Survival analysis suggested no significant difference in RFS between the 557/558 deletion and the other deletions.

Conclusion

This study suggested that mutations in exon 11 of the KIT gene were common with intermediate/high recurrence risk in GISTs patients. Tumor diameter ≥5 cm, and deletions mutations might predict a worse prognosis.

Inflammation and nutritional status indicators as prognostic indicators for patients with locally advanced gastrointestinal stromal tumors treated with neoadjuvant imatinib

BACKGROUND

Previous studies have confirmed that preoperative nutritional-inflammatory indicators can predict prognosis in various malignancies. However, to the best of our knowledge, no study has investigated the assessment of systemic inflammatory immunity index (SII) combined with prognostic nutritional index (PNI) scores to predict prognosis after neoadjuvant treatment with imatinib in locally advanced gastrointestinal stromal tumours (LA-GIST). The aim of this study was to evaluate the predictive value of pretreatment SII-PNI scores in predicting recurrence after neoadjuvant therapy with imatinib in patients with LA-GIST.

METHODS

We retrospectively analyzed 57 patients with LA-GIST who received imatinib neoadjuvant from January 2013 to March 2019. Patients were divided into recurrence and non-recurrence groups according to their follow-up status, and SII and PNI cut-offs were calculated by receiver operating characteristic. The SII-PNI score ranged from 0 to 2 and were categorized into the following: score of 2, high SII (≥ 544.6) and low PNI (≤ 47.2); score of 1, either high SII (≥ 544.6) or low PNI (≤ 47.2); score of 0, no high SII (≥ 544.6) nor low PNI (≤ 47.2).

RESULTS

All patients received imatinib neoadjuvant therapy for a median treatment period of 8.5 months (ranging from 3.2 to 12.6 months), with 8 patients (14.04%) and 49 patients (85.96%) developing recurrence and non-recurrence, respectively. Patients with a high SII-PNI score had a significantly worse recurrence-free survival time than those with a low SII-PNI score (P = 0.022, 0.046), and had a poorer pathological response (P = 0.014). Multivariate analysis demonstrated that the SII-PNI score was an independent prognostic factor for prediction of recurrence-free survival (P = 0.002).

CONCLUSION

The pre-treatment SII-PNI score can be used to predict the efficacy after neoadjuvant treatment with imatinib in patients with LA-GIST, which may be a promising predictor of recurrence-free survival time for patients.

Current evidence on laparoscopic vs. open resection for gastric stromal tumours

Although the use of laparoscopic surgery is increasing, controversy still surrounds its application for malignant conditions. Gastrointestinal stromal tumours (GISTs) are less demanding in terms of lymphadenectomy, meaning that laparoscopic resection might have a more defined benefit when compared with open resection. To the best of our knowledge, no randomized study exists that compares the laparoscopic and open resection of GISTs. The current study aimed to examine the relevant literature by means of a systematic review. A systematic literature search was performed individually by two authors, in which three independent databases were searched using specific search-terms. Titles, abstracts and full texts were screened, as well as references to relevant articles, in order to comprise a comprehensive list of studies. Data were extracted using a detailed pre-agreed spreadsheet. Studies were evaluated according to the modified MINORS criteria. A total of 10 studies were included in the present review, yielding a total of 14 entries. The majority of studies reported significantly improved perioperative outcomes for the laparoscopic approach, including improved duration of operation, blood loss and length of hospital stay. Only four studies reported long-term outcomes and findings that were controversial, with some studies detecting no statistically significant differences, one reporting improved and one reporting worse disease-free and overall survival for the laparoscopic group. Three studies were deemed to be good quality, two of which had not reported significantly different long-term outcomes, while the third had reported significantly improved outcomes in the open resection group. While there is a clear benefit for performing laparoscopic surgery in patients with GIST with regards to perioperative outcomes, when it comes to long-term oncological outcomes, uncertainty over its application remains. The lack of randomized trials, as well as the poor reporting of retrospective studies, limits the amount of evidence that is currently available. Laparoscopic surgery for GIST is certainly safe, feasible and likely cost-effective; however, further studies are required to inform on whether this technique is superior to open resection.