Preservation of Organ Function in Locally Advanced Non-Metastatic Gastrointestinal Stromal Tumors (GIST) of the Stomach by Neoadjuvant Imatinib Therapy

A systematic review and meta-analysis of neoadjuvant imatinib use in locally advanced and metastatic gastrointestinal stromal tumors

BACKGROUND

Several doubts remain regarding the optimal use of neoadjuvant imatinib in gastrointestinal stromal tumors (GISTs), such as ideal treatment duration, patient selection, and long-term survival outcomes. This manuscript provides a comprehensive review on neoadjuvant imatinib treatment outcomes and facilitate evidence-based decision-making for the use of imatinib therapy in GISTs.

METHODS

Four databases (PubMed, EMBASE, Scopus, and Cochrane Library) were searched from inception to September 9, 2023. Meta-analyses of proportions were performed for the outcomes of R0 resection, disease responses, and 1-year, 3-year, and 5-year overall survival (OS) as well as 1-year, 3-year, and 5-year disease free survival (DFS). Sensitivity analyses in the form of leave-one-out analyses, meta-regression, and subgroup analyses were performed for outcomes with substantial statistical heterogeneity.

RESULTS

The search yielded 1254 articles, and 36 studies were included in our analysis. Meta-analysis of proportions revealed that 1-year, 3-year, and 5-year OS was 100%, 94%, and 88%, while 1-year, 3-year and 5-year DFS was 99%, 89%, and 79%, respectively. An R0 resection rate of 89% and a disease response rate of 67% was achieved after a mean duration of treatment of 8.41 ± 0.367 months. KIT exon 9 mutation was significantly associated with poorer 5-year DFS.

CONCLUSION

This study quantified key outcomes for neoadjuvant imatinib in locally advanced and metastatic or recurrent GIST. Patients with gastric and rectal tumous stand to benefit from neoadjuvant imatinib with an optimal treatment duration of 8 months. Furthermore, the potential utility of mutational analysis in guiding treatment with neoadjuvant imatinib was demonstrated.

Organ and function preservation in gastrointestinal cancer: Current and future perspectives on endoscopic ablation

The escalating prevalence of gastrointestinal cancers underscores the urgency for transformative approaches. Current treatment costs amount to billions of dollars annually, combined with the risks and comorbidities associated with invasive surgery. This highlights the importance of less invasive alternatives with organ preservation being a central aspect of the treatment paradigm. The current standard of care typically involves neoadjuvant systemic therapy followed by surgical resection. There is a growing interest in organ preservation approaches by way of minimizing extensive surgical resections. Endoscopic ablation has proven to be useful in precursor lesions, as well as in palliative cases of unresectable disease. More recently, there has been an increase in reports on the utility of adjunct endoscopic ablative techniques for downstaging disease as well as contributing to non-surgical complete clinical response. This expansive field within endoscopic oncology holds great potential for advancing patient care. By addressing challenges, fostering collaboration, and embracing technological advancements, the gastrointestinal cancer treatment paradigm can shift towards a more sustainable and patient-centric future emphasizing organ and function preservation. This editorial examines the evolving landscape of endoscopic ablation strategies, emphasizing their potential to improve patient outcomes. We briefly review current applications of endoscopic ablation in the esophagus, stomach, duodenum, pancreas, bile ducts, and colon.

Long-term outcomes of a phase II study of neoadjuvant imatinib in large gastrointestinal stromal tumors of the stomach

BACKGROUND

Neoadjuvant treatment is recommended for large GISTs due to their friability and risk of extensive operations; however, studies on the indications and long-term results of this approach are lacking.

METHODS

Patients with large (≥ 10 cm) gastric GISTs were enrolled from multiple centers in Korea and Japan after a pathologic confirmation of c-KIT ( +) GISTs. Imatinib (400 mg/d) was given for 6-9 months preoperatively, and R0 resection was intended. Postoperative imatinib was given for at least 12 months and recommended for 3 years.

RESULTS

A total of 56 patients were enrolled in this study, with 53 patients receiving imatinib treatment at least once and 48 patients undergoing R0 resection. The 5-year overall survival and progression-free survival rates were 94.3% and 61.6%, respectively. Even patients with stable disease by RECIST criteria responded well to preoperative imatinib treatment and could undergo R0 resection, with most being evaluated as partial response by CHOI criteria. The optimal reduction in tumor size was achieved with preoperative imatinib treatment for 24 weeks or more. No resumption of imatinib treatment was identified as an independent prognostic factor for recurrence after R0 resection. No additional size criteria for a higher risk of recurrence were identified in this cohort with a size of 10 cm or more.

CONCLUSIONS

Neoadjuvant imatinib treatment is an effective treatment option for gastric GISTs 10 cm or larger. Postoperative imatinib treatment is recommended even after R0 resection to minimize recurrence.

Prediction of the mitotic index and preoperative risk stratification of gastrointestinal stromal tumors with CT radiomic features

OBJECTIVE

The objective is to develop a mitotic prediction model and preoperative risk stratification nomogram for gastrointestinal stromal tumor (GIST) based on computed tomography (CT) radiomic features.

METHODS

A total of 267 GIST patients from 2009.07 to 2015.09 were retrospectively collected and randomly divided into (6:4) training cohort and validation cohort. The 2D-tumor region of interest was delineated from the portal-phase images on contrast-enhanced (CE)-CT, and radiomic features were extracted. Lasso regression method was used to select valuable features to establish a radiomic model for predicting mitotic index in GIST. Finally, the nomogram of preoperative risk stratification was constructed by combining the radiomic features and clinical risk factors.

RESULTS

Four radiomic features closely related to the level of mitosis were obtained, and a mitotic radiomic model was constructed. The area under the curve (AUC) of the radiomics signature model used to predict mitotic levels in training and validation cohorts (training cohort AUC = 0.752; 95% confidence interval [95%CI] 0.674-0.829; validation cohort AUC = 0.764; 95% CI 0.667-0.862). Finally, the preoperative risk stratification nomogram combining radiomic features was equivalent to the clinically recognized gold standard AUC (0.965 vs. 0.983) (p = 0.117). The Cox regression analysis found that the nomogram score was one of the independent risk factors for the long-term prognosis of the patients.

CONCLUSION

Preoperative CT radiomic features can effectively predict the level of mitosis in GIST, and combined with preoperative tumor size, accurate preoperative risk stratification can be performed to guide clinical decision-making and individualized treatment.

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.

Needle tract seeding and abdominal recurrence following pre-treatment biopsy of gastrointestinal stromal tumors (GIST): results of a systematic review

BACKGROUND

Gastrointestinal stromal tumors (GIST) are rare abdominal tumors. Pretreatment biopsies may be used to diagnose a GIST and enable tailored treatment. Some experts are skeptical about biopsies because they fear tumor cell seeding. The objective of this study was to determine if pretreatment biopsy is associated with increased tumor recurrence.

METHODS

We performed a systematic literature search and included studies assessing the oncological outcome of GIST patients who underwent a pre-treatment core needle biopsy or fine needle aspiration. We assessed methodological quality with the Newcastle-Ottawa-Scale for non-randomized studies. This review was registered in the PROSPERO database (CRD42021170290).

RESULTS

Three non-randomized studies and eight case reports comprising 350 patients were eligible for inclusion. No prospective study designed to answer the review question was found. One case of needle tract seeding after percutaneous core needle biopsy of GIST was reported. None of the studies reported an increased rate of abdominal recurrence in patients with pretreatment biopsy.

CONCLUSIONS

The existing evidence does not indicate a relevant risk of needle tract seeding or abdominal recurrence after pre-treatment biopsy of GIST. Biopsy can safely be done to differentiate GIST from other tumors and to select the most appropriate treatment.

The role of neoadjuvant imatinib in gastrointestinal stromal tumor (GIST) patients - 20 years of experience from a tertial referral center

Surgery is the cornerstone of gastrointestinal stromal tumor (GIST) treatment, and adjuvant therapy with imatinib has improved survival for high‐risk tumors. The use of imatinib preoperatively has been increasing, but efficacy and impact on patient outcomes have not been formally investigated. This is a retrospective study from a single‐center cohort of patients diagnosed with GIST and treated with neoadjuvant imatinib at Karolinska University Hospital in Stockholm, Sweden over a 20‐year period. Eighty‐four patients diagnosed with GIST and treated with neoadjuvant imatinib were identified and included. Tumors were located throughout the whole gastrointestinal tract but most frequently in the stomach (n = 29; 35%) and the small intestine (n = 30; 36%), followed by the rectum (n = 12; 14%) and the gastroesophageal junction (n = 10; 12%). The tumors were large (mean 10.5 cm) and decreased after treatment (mean 7.6 cm). Main indications for neoadjuvant imatinib were tumor size or anatomical location. None of the patients with stomach tumors and four patients with tumors near the gastroesophageal junction underwent gastrectomy. Three patients with tumors in the small intestine underwent pancreaticoduodenectomy, whereas seven patients with rectal tumors underwent rectal amputation. After surgery, 94% (n = 79) of the tumors had R0‐resection. About one‐fourth experienced local relapse or distant metastasis. In conclusion, neoadjuvant imatinib can reduce tumor size and prevent high morbidity due to more extensive surgery, or at least reduce the extent of the surgery, especially for tumors in the stomach or small intestine.

[Surgical and interdisciplinary treatment of gastrointestinal stromal tumors]

Gastrointestinal stromal tumors (GISTs) are the most frequent potentially malignant mesenchymal tumors of the gastrointestinal tract. The treatment of GISTs has been revolutionized since imatinib and other tyrosine kinase inhibitors were introduced for the treatment of GISTs, which inhibit the tyrosine kinases c‑KIT and platelet-derived growth factor receptor (PDGFR) alpha. Even after the introduction of this targeted treatment GISTs can only be cured by surgical resection. With interdisciplinary multimodal treatment the prognosis of metastasized GIST can now be further improved by surgical resection of the primary tumor and the metastases, potentially leading to a cure. Neoadjuvant therapy can reduce the extent of surgical resection and hereby enable organ preservation and reduce surgical morbidity. To evaluate molecular and clinical predictors and to offer an optimal therapeutic plan, patients with GISTs and certainly patients with advanced GISTs should be evaluated by interdisciplinary sarcoma boards.

Surgical Approaches and Oncological Outcomes in the Management of Duodenal Gastrointestinal Stromal Tumors (GIST)

BACKGROUND

Duodenal gastrointestinal stromal tumors (GIST) are a rare subset of GIST. Their surgical management in this anatomically complex region consists of varied approaches, and the administration of imatinib mesylate (IM) has not been clarified.

METHODS

We retrospectively reviewed patients with duodenal GIST treated during a 10-year-period. We analysed the clinicopathological characteristics and survival factors and evaluated the perioperative and long-term outcomes based on the extent of resection ((ocal-resection (LR) versus pancreaticoduodenectomy (PD)) and the IM-administration. The median follow-up period was 60 months (range, 12-140).

RESULTS

A total of thirteen patients (M:F = 7:6) with median age of 64 years (range, 42-77) underwent resection of duodenal GIST. Median tumor size was 5.2 cm (range, 1.5-13.3). Eight patients (61.5%) underwent LR and five patients (38.5%) PD. R0-resection was achieved in 92.5%. Neoadjuvant IM-therapy was administered in five patients leading to tumor downsizing and in 40% to less-extended resection. The PD group consisted of larger tumors with higher mitotic count, mostly located in D2 (p = 0.031). The PD group had longer operative time (p = 0.026), longer hospital stay (p = 0.016), and higher rate of postoperative complications (p = 0.128). The actuarial 1-, 3-, and 5-year overall survival were 92.5%, 84%, and 73.5%, respectively, whereas the disease-free survival rates at 1, 3, and 5 years were 91.5%, 83%, and 72%, respectively. A tendency towards increased risk of disease recurrence was demonstrated for patients with tumor >5 cm and high-risk potential. There was not statistic survival benefit for one or the other surgical approach.

CONCLUSION

The type of resection depends on duodenal site of origin and tumor size. LR can be the treatment of choice for duodenal GIST whenever technically feasible. Recurrence of duodenal GIST is dependent on tumor biology rather than surgical approach. Administration of IM in neaodjuvant setting should be considered in cases with high-risk GIST scheduled for PD since it might facilitate less-extended resection.

Investigation of the factors influencing surgical treatment of duodenal gastrointestinal stromal tumors

BACKGROUND

Duodenal gastrointestinal stromal tumor (DGIST) is a rare tumor with a specific anatomic site and biological characteristics. As the incidence of lymph node metastasis is very low, the main treatment method is surgery. Two main surgical techniques (local resection and Whipple) are performed in patients with DGISTs. The critical question is which surgical technique to choose.

AIM

To identify factors influencing the choice of surgery for DGISTs.

METHODS

The clinicopathological data of patients with DGISTs who underwent surgery between January 1999 and January 2021 were analyzed. We used the Student’s t-test or Mann-Whitney U-test and the χ² test or Fisher’s exact test to determine the differences between the two groups of patients. Furthermore, we used logistic analysis to identify the relevant factors and independent factors related to the type of surgery. The Kaplan-Meier method was used to analyze the patient’s survival information and Cox regression analysis was performed to determine prognostic risk factors.

RESULTS

Overall, 86 patients were analyzed, including 43 men (50%) and 43 women (50%). We divided the patients into two groups based on surgical technique (local resection or Whipple surgery). There were no differences in the age, mitotic figures, and complications between the two groups; however, the tumor size, tumor location, risk grade, postoperative hospital stay, and abdominal drainage time were significantly different. Based on univariate logistic analysis, the Whipple procedure was chosen if the tumor size was ≥ 5.0 cm, the tumor was located in the descending part of the duodenum, or the risk grade was medium or high. In our research, the five-year overall survival rate of patients was more than 90%. We also describe two DGIST patients with liver metastases at first diagnosis and analyzed their management in order to provide advice on complicated cases.

CONCLUSION

The Whipple procedure was performed if the primary tumor was in the descending part of the duodenum, tumor size was ≥ 5.0 cm, or the tumor risk grade was medium or high.

Recent Progress and Challenges in the Diagnosis and Treatment of Gastrointestinal Stromal Tumors

Simple Summary

Gastrointestinal stromal tumors (GIST) are potentially malignant tumors and require evidence-based surgical and/or medical treatment. Laparoscopy has similar safety and prognostic outcomes to those of laparotomy and is currently a standard procedure for localized GISTs. However, surgery for gastric GISTs less than 2 cm may be re-evaluated due to the indolent nature of the GIST and other competing risks among GIST patients. A work-up with endoscopy and endoscopic ultrasonography as well as endoscopic or percutaneous biopsy is important for the preoperative diagnosis of GISTs. Medical treatment with tyrosine kinase inhibitors is the mainstay for recurrent/metastatic GISTs. The activity of an individual drug is well correlated with gene alterations, and, in the era of precision medicine, cancer genome profiling should be considered before medical treatment.

Abstract

Gastrointestinal stromal tumors (GISTs) are the most frequent malignant mesenchymal tumors in the gastrointestinal tract. The clinical incidence of GISTs is estimated 10/million/year; however, the true incidence is complicated by frequent findings of tiny GISTs, of which the natural history is unknown. The initial work-up with endoscopy and endoscopic ultrasonography plays important roles in the differential diagnosis of GISTs. Surgery is the only modality for the permanent cure of localized GISTs. In terms of safety and prognostic outcomes, laparoscopy is similar to laparotomy for GIST treatment, including tumors larger than 5 cm. GIST progression is driven by mutations in KIT or PDGFRA or by other rare gene alterations, all of which are mutually exclusive. Tyrosine kinase inhibitors (TKIs) are the standard therapy for metastatic/recurrent GISTs. Molecular alterations are the most reliable biomarkers for TKIs and for other drugs, such as NTRK inhibitors. The pathological and genetic diagnosis prior to treatment has been challenging; however, a newly developed endoscopic device may be useful for diagnosis. In the era of precision medicine, cancer genome profiling by targeted gene panel analysis may enable potential targeted therapy even for GISTs without KIT or PDGFRA mutations.