Role of metastasectomy for recurrent/metastatic gastrointestinal stromal tumors based on an analysis of the Kinki GIST registry

A successful complete resection for multidrug-resistant giant gastrointestinal stromal tumor invading the transverse colon with multiple liver metastases in a young female: a case report

BACKGROUND

Gastrointestinal stromal tumors (GISTs) are rare in young people and are often detected after becoming symptomatic or at an advanced stage. Herein, we report a case of complete reduction surgery for a substantially large malignant gastric GIST with multiple liver metastases in a young woman who successfully resulted in R0 surgery.

CASE PRESENTATION

An 18-year-old woman presented to our hospital with anorexia and vomiting, and was diagnosed with a 17 cm gastric GIST with transverse colon invasion and multiple liver metastases. Due to being considered unresectable, tyrosine and multi-kinase inhibitor therapy were administered up to the fourth line yielding no response. After careful discussion at a multidisciplinary team conference, pancreatoduodenectomy or distal gastrectomy, transverse colectomy, and resection of the liver metastases were planned. Consequently, distal gastrectomy, transverse colectomy, resection of the liver metastases, and incidental peritoneal metastases were performed. Although the primary goal of the surgery was to reduce the volume of the tumor as much as possible, the results revealed that the complete removal of all detectable tumors was achieved. No recurrence was observed after surgery for 27 months with long-term adjuvant imatinib therapy.

CONCLUSIONS

Even for highly advanced GISTs, aggressive surgery followed by adjuvant drug therapy may prolong survival in young patients.

The impact of contour maps on estimating the risk of gastrointestinal stromal tumor recurrence: indications for adjuvant therapy: an analysis of the Kinki GIST registry

INTRODUCTION

Contour maps enable risk classification of GIST recurrence in individual patients within 10 postoperative years. Although contour maps have been referred to in Japanese guidelines, their usefulness and role in determining indications for adjuvant therapy is still unclear in Japanese patients. The aims of this study are to investigate the validity of contour maps in Japanese patients with GIST and explore the new strategy for adjuvant therapy.

MATERIALS AND METHODS

A total of 1426 Japanese GIST patients who were registered to the registry by the Kinki GIST Study Group between 2003 and 2012 were analyzed. Patients who had R0 surgery without perioperative therapy were included in this study. The accuracy of contour maps was validated.

RESULTS

Overall, 994 patients have concluded this study. Using contour maps, we validated the patients. The 5-year recurrence-free survival rates of patients within the GIST classification groups of 0-10%, 10-20%, 20-40%, 40-60%, 60-80%, 80-90%, and 90-100% were 98.1%, 96.6%, 92.3%, 48.0%, 37.3%, 41.0% and 42.4%, respectively. We confirmed that this classification by contour maps was well reflected recurrence prediction. Further, in the high-risk group stratified by the modified National Institutes of Health consensus criteria (m-NIHC), the 10-year RFS rate was remarkably changed at a cutoff of 40% (0-40% group vs. 40-100% group: 88.7% vs. 50.3%, p < 0.001).

CONCLUSION

Contour maps are effective in predicting individual recurrence rates. And it may be useful for the decision of individual strategy for high-risk patients combined with m-NIHC.

Liver resection for metastatic GIST tumor improves survival in the era of tyrosine kinase inhibitors: a systematic review and meta-analysis

INTRODUCTION

Survival for gastrointestinal stromal tumor (GIST) has been increasing over the years after the introduction of tyrosine kinase inhibitors. However, the role of metastasectomy for GIST is still controversial. Patients are currently treated with imatinib or sunitinib in case of imatinib failures as optimal medical therapy for metastatic GIST.

METHODS

The Pubmed, EMBASE, and Cochrane Library were systematically searched. Overall survival following liver resection ± tyrosine kinase inhibitor treatment for metastatic GIST was compared to treatment with tyrosine kinase inhibitors alone.

RESULTS

Eleven studies including both randomized control trials and retrospective cohort studies were included in the final analysis with a total of 988 patients. Seven studies encompassed data on 556 patients with isolated liver metastases (219 surgery ± drug groups and 337 drug-only groups) were included. Overall survival was significantly improved in patients undergoing liver resection ± drug therapy in comparison to drug therapy alone. [HR (95%CI) = 2.10 (1.58, 2.79); p<0.00001]. Subgroup analysis showed that patients also had improved progression free survival based on 4 studies. [HR (95%CI) = 1.92 (1.43, 2.56); p<0.00001]. In case of concurrent liver and peritoneal metastases, patients showed improved overall survival with aggressive surgical approaches based on 10 studies. [HR (95%CI) = 1.90 (1.56, 2.31); p<0.00001].

CONCLUSION

This meta-analysis found that liver resection for patients with metastatic GIST regardless of peritoneal metastases improved progression free and overall survival in conjunction with tyrosine kinase inhibitors as compared with medical therapy alone. Furthermore, liver resections did not have any immediate detrimental impact on survival in the group of patients selected.

Role of Surgery in the Management of Liver Metastases From Gastrointestinal Stromal Tumors

Background

The clinical benefit of hepatectomy in patients with liver metastases from gastrointestinal stromal tumors (GIST) has not been well defined in this era of tyrosine kinase inhibitor (TKI). Our study aims to demonstrate the survival advantage of adding hepatectomy in patients with GIST liver metastases.

Methods

Information on patients with metastatic GIST treated or consulted between January 2006 and December 2018 was retrieved. Patients without extrahepatic metastases were included and classified into the surgical (S group) and non-surgical (NS group). Clinicopathological features were compared and their association with survival was assessed.

Results

A total of 119 patients were included in this retrospective analysis, 62 in the S group and 59 in the NS group. Comparison of clinicopathological features showed that a markedly higher proportion of patients in the S group had ≤3 hepatic lesions (79.0% vs. 29.8%, p<0.001). After a median follow-up duration of 56 months, patients in the S group had significantly better progression-free survival (PFS) and marginally improved overall survival (OS) than those in the NS group (3y PFS:86.2% vs. 64.6%, p=0.002; 5y OS: 91.5% vs. 78.3%, p=0.083). After propensity score matching, multivariate analysis identified hepatectomy as the only significant prognostic factor for PFS while age, hepatectomy and max tumor diameter were significant predictor for OS.

Conclusions

Addition of hepatectomy provided longer disease control in patients with metastatic GIST confined to the liver. Upfront hepatectomy followed by imatinib therapy is worthwhile trying in patients with single and easily removable lesions.

A liver metastasis 7 years after resection of a low-risk duodenal gastrointestinal stromal tumor

Duodenal gastrointestinal stromal tumors (dGISTs) are rare, and a lack of consensus exists regarding their treatment, particularly for recurrent disease. We herein report a rare case of liver metastasis 7 years after resection of a low-risk duodenal gastrointestinal stromal tumor. A 45-year-old woman revealed positive fecal occult blood. Upper gastrointestinal endoscopy revealed a submucosal duodenal tumor with ulceration and oozing on the apex. Endoscopic ultrasound showed a hypoechoic mass originating in the submucosa. Contrast-enhanced abdominal computed tomography (CT) revealed a 30-mm hyper-vascular tumor in the duodenal bulb. The patient underwent partial resection of the duodenal bulb with distal gastrectomy, followed by Roux-en-Y reconstruction. Histopathological evaluation revealed a tumor comprised of spindle-shaped cells including 5 mitotic figures per 50 high-power fields. Immunohistochemical evaluation indicated that the tumor cells were positive for c-Kit and CD34 expression. The tumor was diagnosed as low-risk dGIST. Postoperative follow-up was continued, and 7 years later, CT revealed a 39-mm enhanced tumor in liver segment 4. The tumor was diagnosed as a metastatic liver tumor, and the patient underwent S4 partial hepatectomy. As a result of histological and immunohistochemical analysis, the tumor was diagnosed as a liver metastasis from dGIST. The patient has been receiving oral imatinib 400 mg daily and remains free of disease 5 years after her last surgery. Low-risk dGIST can metastasize relatively long after surgery. However, an excellent long-term prognosis may be achieved by combining complete resection and imatinib therapy in patients with recurrent liver metastases.

Surgical Management of Metastatic Gastrointestinal Stromal Tumors

OPINION STATEMENT

Treatment with the tyrosine kinase inhibitor (TKI), imatinib is the standard first-line treatment for metastatic gastrointestinal stromal tumors (GISTs). Unfortunately, acquired c-kit mutations cause secondary resistance to imatinib in a median of 18-24 months. Sunitinib and regorafenib are multi-kinase inhibitors that can be used as second-line or third-line therapy in imatinib-resistant or -intolerant GISTs, respectively. Ripretinib (a switch-control tyrosine kinase inhibitor) has recently been approved for fourth-line treatment in metastatic GIST. The TKI avapritinib has been approved for metastatic GIST harboring the imatinib-resistant PDGFRA exon 18 mutation. Although TKI therapies have revolutionized the treatment of metastatic GISTs, they cannot cure metastatic GISTs. Therefore, cytoreductive surgery is of considerable interest and has been accordingly investigated. Retrospective non-randomized studies demonstrated the feasibility and safety of continuous TKI therapy and surgical resection. Most studies demonstrate response to TKI therapy, completeness of resection, extent of disease, and surgical complexity as predictors of outcomes. Most TKIs can be stopped shortly before surgery and restarted shortly after. There is no known survival benefit from debulking operations or R2 resections and this should not be considered. However, debulking/palliative surgery may be necessary for patients with complications of hemorrhage, pain, or intestinal obstruction. SDH-deficient GISTs have an indolent natural history despite metastatic disease and may be another uncommon subgroup that would benefit from surgical debulking (R2 resection). At the time of operation, care should be taken to avoid tumor rupture. After surgical resection, patients should resume tyrosine kinase inhibitor (TKI) therapy as soon as possible and be monitored for disease progression. In all patients with metastatic GIST, the decision to pursue metastasectomy for GIST should be made in a multidisciplinary setting and be individualized according to patient age, comorbidities, functional status, symptoms, mutation status, extent of disease, completeness of resection, TKI response, and goals of the patient.

Solitary peritoneal metastasis of gastrointestinal stromal tumor: A case report

BACKGROUND

A gastrointestinal stromal tumor (GIST) is a mesenchymal tumor of the gastrointestinal tract that is most commonly found in the stomach. Recurrence of GISTs mostly occurs in the liver or peritoneum, and in most cases, multiple metastases occur. As a solitary peritoneal metastasis is rare, an appropriate treatment strategy has not been established. Here, we report a case of solitary peritoneal metastasis after complete resection of gastric GIST.

CASE SUMMARY

A 76-year-old woman was diagnosed with stomach GIST and underwent laparoscopic local resection using the CLEAN-NET method. As the recurrence risk was intermediate, adjuvant imatinib therapy was not administered. Two years after surgery, routine computed tomography revealed an abdominal mass between the dorsal side of the right hepatic lobe and right kidney. Other imaging tests did not reveal any abnormalities. Laparoscopic observation showed that the tumor was located at the retroperitoneum, and intraperitoneal dissemination was not found. Therefore, we performed laparoscopic tumor resection. Immunohistochemically, the tumor was positive for c-kit and CD34 and had a relatively high mitotic index and MIB-1 Labeling index. We administered adjuvant imatinib therapy. There was no evidence of recurrence 3 years after the operation.

CONCLUSION

This is the first reported case of a solitary recurrence of GIST in the peritoneum treated with complete laparoscopic resection.

[Imatinib and beyond-what is important for surgery?]

The treatment of gastrointestinal stromal tumors (GIST) has dramatically improved since the introduction of small molecule KIT proto-oncogene receptor tyrosine kinase inhibitors. Nevertheless, the cure of patients is still based on surgical treatment of the primary tumor. The chance of long-term tumor control by tyrosine kinase inhibitors (TKI) even in the metastatic setting also appears to be improved after achieving a surgical complete resection. The decision on which patients will most likely profit from multimodal treatment approaches is increasingly based on complex molecular predictors in addition to clinical factors and also a profound understanding of the biology of GIST that requires discussion in a multidisciplinary, highly experienced treatment team. Novel, more potent inhibitors enable a response to treatment in so far treatment-refractory GIST subtypes, such as the platelet-derived growth factor receptor (PDGFR) D842V mutated GIST subtype and also appear to show treatment benefits even in KIT mutated GIST after the failure of all approved treatments. These treatments are expected to profoundly change treatment algorithms in the near future.

Recurrent Gastrointestinal Stromal Tumors in the Imatinib Mesylate Era: Treatment Strategies for an Incurable Disease

Introduction

Recurrence of gastrointestinal stromal tumors (GISTs) after surgical resection and imatinib mesylate (IM) adjuvant therapy poses a significant treatment challenge. We present the case of a patient who underwent surgical resection after recurrence and review the current literature regarding treatment.

Case Presentation

A 58-year-old man with a large intra-abdominal jejunal GIST was treated with complete surgical resection followed by IM. The patient experienced disease recurrence 3.5 years later and underwent IM dose escalation and reresection.

Conclusion

Current strategies to treat recurrent GIST include dose escalation, modifying adjuvant tyrosine kinase inhibitor therapy, and surgery. High-level evidence will be required to better define the combinatory roles of tyrosine kinase inhibitor therapy, guided by molecular profiling, and surgery in the management of recurrent GIST.