Development and validation of a prognostic nomogram for recurrence-free survival after complete surgical resection of localised primary gastrointestinal stromal tumour: a retrospective analysis

Prediction of morbidity following cytoreductive surgery for metastatic gastrointestinal stromal tumour in patients on tyrosine kinase inhibitor therapy

BACKGROUND

Although cytoreductive surgery has been shown to be beneficial in carefully selected patients with metastatic gastrointestinal stromal tumours (GISTs) treated with tyrosine kinase inhibitors (TKIs), factors predictive of postoperative morbidity have not been investigated previously.

METHODS

A surgical complexity score for GIST metastasectomy (GM-SCS) composed of patient-related and surgical factors was assigned retrospectively to patients with metastatic GIST treated with TKI therapy and surgery at two institutions between 2002 and 2014. The ability of clinicopathological factors and GM-SCS to predict postoperative morbidity was assessed by means of a multivariable logistic regression model. Postoperative complications were categorized using the Clavien-Dindo classification.

RESULTS

Some 400 operations on 323 patients with metastatic GIST on TKIs were included. Complications were observed following 110 operations (27·5 per cent) including 70 major complications (grade III-V) (17·5 per cent of 400 operations). Patients were divided into low (5 points or less; 100 patients, 25·0 per cent), intermediate (6-9 points; 191, 47·8 per cent) and high (at least 10 points; 109, 27·3 per cent) complexity scoring groups based on the GM-SCS. An intermediate (odds ratio (OR) 2·88; P = 0·008) and high (OR 5·40; P < 0·001) GM-SCS were independent predictors of overall complications, whereas only a high GM-SCS was independently predictive of a major complication (OR 3·65; P = 0·018). Metastatic mitotic index was also an independent predictor of overall complications (OR 2·55; P = 0·047). GM-SCS did not predict progression-free or overall survival.

CONCLUSION

A gastrointestinal stromal tumour metastastectomy surgical complexity score can predict morbidity, which may help in preoperative risk stratification and optimal treatment planning.

Gastrointestinal stromal tumors: 16 years' experience within a university hospital

AIM

the aim was to convey our 16-year experience regarding gastrointestinal stromal tumors within in a high volume university hospital. Factors that may impact on patient survival were evaluated.

MATERIAL AND METHODS

all patients diagnosed with gastrointestinal stromal tumors in our clinic over a 16-year period were retrospectively evaluated. All patients included in the study had their tumors surgically resected. Survival analyses were performed using the Kaplan-Meier method. Survival time comparisons between groups were performed using the log-rank test. The effect of continuous variables on survival times were evaluated via a Cox-regression analysis with a backward conditional method.

RESULTS

one hundred and thirty-five patients (76 males and 59 females) were included into the study and the mean age was 62.8 ± 13.3 years. Overall survival time was 121.3 ± 7.0 months and the 5-year survival rate was 66.6 ± 4.2%. Patients with colorectal tumors had significantly lower survival times than patients with tumors located in the stomach (p = 0.001) and small intestine (p = 0.033). Patients with moderate risk scores had a significantly longer survival compared to patients with high risk scores (p = 0.003) and patients with tumor recurrence had a significantly shorter survival (p < 0.001). There was no significant relationship between survival and factors such as gender and tumor size (p > 0.05). However, age, Ki-67 and the mitotic index were poor prognostic factors and C-kit was considered as a good prognostic factor.

CONCLUSION

some of the findings in this study are consistent with published data. However, our data significantly differs from previous studies such as the common finding of the effect of gender and tumor size on survival.

Asian consensus guidelines for gastrointestinal stromal tumor: what is the same and what is different from global guidelines

There are some disparities between the clinical practice and profiles of cancer in Asia and those in Europe & North America. In Asia, surgical oncologists still have a major role in the multidisciplinary therapy of gastrointestinal stromal tumor (GIST), whereas medical oncologists hold this status in the West. Although the incidence of clinical GIST is considered similar between the two areas, small gastric GISTs are more frequently treated by surgery in East Asia compared with Europe & North America. The diagnosis and treatment of small submucosal tumors (SMTs), including GIST, is important in Asian clinical practice guidelines for GIST. Most items of Asian and Western GIST guidelines are very similar. There are slight differences between the two guidelines in the degree of recommendation, which may come from disparities of clinical practice and available medicines. Importantly, most clinical evidence in the GIST guidelines has been established by clinical trials conducted in Western countries, and the number of clinical trials is still limited in Asia, suggesting that Asian GIST patients may have limited access to investigational drugs after standard therapy. Finally, both Asian and Western GIST guidelines are well-harmonized in some parts, and their contents may reflect the medical circumstances of each region.

Management of rectal gastrointestinal stromal tumor

Gastrointestinal stromal tumor (GIST) is the most common mesenchymal neoplasm of the gastrointestinal tract. However, rectal GIST is rare, the incident rate of it is approximately 5% of all GISTs. Rectal GIST symptoms generally include bleeding and/or pain and occasionally, urinary symptoms. Immunohistochemical evaluation finds that most rectal GIST tumors are CD117 (KIT) positive, and are sometimes CD34, platelet-derived growth factor receptor alpha (PDGFRA), smooth muscle actin, S-100, or vimentin positive. The National Institutes of Health (NIH) classifies rectal GIST as very-low risk, low risk, intermediate risk, or high risk, and the frequencies have been estimated as 0-23.8% for very-low risk, 0-45% for low risk, 0-34% for intermediate risk, and 21-100% for high risk tumors. The first-line treatment for localized GIST is curative resection, but is difficult in rectal GIST because of anatomical characteristics such as the deep, narrow pelvis and proximity to the sphincter muscle or other organs. Several studies noted the efficacy of the minimally invasive surgery, such as trans-anal, trans-sacral, trans-vaginal resection, or laparoscopic resection. The appropriate surgical procedure should be selected depending on the case. Imatinib mesylate (IM) is indicated as first-line treatment of metastatic or unresectable GIST, and clinical outcomes are correlated with KIT mutation genotype. However, the KIT mutation genotypes in rectal GIST are not well known. In this review, as in other GISTs, a large proportion (59-100%) of rectal GISTs carry exon 11 mutations. Although curative resection is indicated for localized rectal GIST, a high rate of local recurrence is a problem. Multimodal therapy including perioperative IM may improve postoperative outcomes, contributing to anus-preserving surgery. Moreover, KIT mutation analysis before IM treatment is important. This review summarizes current treatment strategies for rectal GIST.

The Effect of Marital Status on Survival of Patients with Gastrointestinal Stromal Tumors: A SEER Database Analysis

Background

Marital status has been reported to be a prognostic factor in multiple malignancies. However, its prognostic value on gastrointestinal stromal tumors (GISTs) have not yet been determined. The objective of the present analysis was to assess the effects of marital status on survival in patients with GISTs.

Methods

The Surveillance, Epidemiology, and End Results (SEER) database was used to analyze 6195 patients who were diagnosed with GISTs from 2001 to 2014. We also use Kaplan-Meier analysis and Cox regression to analyze the impact of marital status on cancer-specific survival (CSS).

Results

Patients in the married group had more frequency in white people, more high/moderate grade tumors, and were more likely to receive surgery. Widowed patients had a higher proportion of women, a greater proportion of older patients (>60 years), and more common site of the stomach. Multivariate analysis demonstrated that marital status was an independent prognostic factor for GISTs (P < 0.001). Married patients had better CSS than unmarried patients (P < 0.001). Subgroup analysis suggested that widowed patients had the lowest CSS compared with all other patients.

Conclusions

Marital status is a prognostic factor for survival in patients with GISTs, and widowed patients are at greater risk of cancer-specific mortality.

Long-term Results of Adjuvant Imatinib Treatment for Localized Gastrointestinal Stromal Tumors after Surgery

Objective:

Despite the development of two significant classifications for recurrence risk evaluation among patients engaged with gastrointestinal stromal tumor and corresponding treatment criteria, recurrence happens in a number of the patients who were once classified as ineligible for treatment and hence removed from treatment program. As such, the aim of the present study is to increase the number of patients recognized as eligible for treatment, so as to further reduce recurrence rate of this disease.

Materials and Methods:

A total of 26 patients from Ilam, Kermanshah, Lorestan, Kurdistan, and some parts of Hamedan, entered this study from 2006 until 2016. The western provinces included have similar socioeconomical conditions. Inclusion criteria were operable tumors confirmed radiologically with a gross size larger than 3 centimeters regardless of the mitosis rate in microscopic power fields, tumor location, or presence of peritoneal involvement during the surgery. Imatinib capsules were administered daily at 400 mg for 3 years. The patients were followed up every 3 months by radiology, ultrasonography, biochemical assessment, and clinical examination.

Results and Conclusions:

The overall survival after 10-years follow up was 100%, while 5-year survival without relapse was 95%. Mean overall survival was 106 months, and only one patient who had limited peritoneal involvement experienced relapse and he is still alive after 2 years. The drug was well tolerated and no significant side effects were observed.

Systematic review of current prognostication systems for primary gastrointestinal stromal tumors

BACKGROUND

The advent of tyrosine kinase inhibitors as adjuvant therapy has revolutionized the management of GIST and emphasized the need for accurate prognostication systems. Numerous prognostication systems have been proposed for GIST but at present it remains unknown which system is superior. The present systematic review aims to summarize current prognostication systems for primary treatment-naive GIST.

METHODS

A literature review of the Pubmed and Embase databases was performed to identify all published articles in English, from the 1st January 2002 to 28th Feb 2017, reporting on clinical prognostication systems of GIST.

RESULTS

Twenty-three articles on GIST prognostication systems were included. These systems were classified as categorical systems, which stratify patients into risk groups, or continuous systems, which provide an individualized form of risk assessment. There were 16 categorical systems in total. There were 4 modifications of the National Institute of Health (NIH) system, 2 modifications of Armed Forces Institute of Pathology (AFIP) criteria and 3 modifications of Joensuu (modified NIH) criteria. Of the 7 continuous systems, there were 3 prognostic nomograms, 3 mathematical models and 1 prognostic heat/contour maps. Tumor size, location and mitotic count remain the main variables used in these systems.

CONCLUSION

Numerous prognostication systems have been proposed for the risk stratification of GISTs. The most widely used systems today are the NIH, Joensuu modified NIH, AFIP and the Memorial Sloan Kettering Cancer Center nomogram. More validation and comparison studies are required to determine the optimal prognostication system for GIST.

The incidence, mutational status, risk classification and referral pattern of gastro-intestinal stromal tumours in the Netherlands: a nationwide pathology registry (PALGA) study

Symptomatic gastrointestinal stromal tumours (GIST) are infrequent with an incidence of 12.7 per million inhabitants in the western population. We studied whether the incidence of GIST has further increased between 2003 and 2012 and assessed the frequency of mutations, risk groups, histological subtypes and immunohistochemistry results. From PALGA, the nationwide Dutch Pathology Registry, pathology excerpts from all patients with a GIST or GIST-like tumour between 2003 and 2012 were retrieved to calculate incidence rates. Full pathology reports were retrieved of resections in 2011 and 2012 to study the frequency of mutations, risk groups, histological subtypes and immunohistochemistry results. The incidence of GIST increased to 17.7 per million inhabitants in 2012 with a median age of 67 years. Mutational analysis was performed in 33.9% of patients with a resection between 2011 and 2012 (KIT mutation 67.5%, PDGFRA 16.3%, wild-type 11.4%). The percentage of high risk patients in the different risk classifications varied from 19.9% to 38.0% depending on the used classification. Only 35.9% of patients had diagnosis or revision of pathology diagnosis within three months in a designated GIST referral centre. No increase in proportion of central pathology reviews was found. Proportion of patients with mutational analysis increased over the years. The registered incidence of GIST, 17.7 per million inhabitants in 2012 in the Netherlands, is still rising. Despite incorporation in the ESMO GIST guidelines since 2008 for mutational testing and since 2010 for central review of pathology, both are performed in a minority of patients.

SSAT State-of-the-Art Conference: Current Surgical Management of Gastric Tumors

INTRODUCTION

The current era of gastric surgery is marked by low morbidity and mortality rates, innovative strategies to approach resections with a minimally invasive fashion or hyperthermic intraperitoneal chemotherapy (HIPEC), as well as improved understanding of the biology of sporadic and hereditary stromal, neuroendocrine, and epithelial malignancies.

METHODS

In 2017, the Society for Surgery of the Alimentary Tract convened a State-of-the-Art Conference on Current Surgical Management of Gastric Tumors with both international experts and emerging leaders in the field of gastric surgery.

RESULTS

Martin D. McCarter, MD of the University of Colorado discussed the current management of gastric gastrointestinal stromal tumors (GIST). Kaitlyn J. Kelly, MD of the University of California, San Diego discussed the management of gastric carcinoid tumors. Jeffrey A. Norton of Stanford University discussed recent advances in the management of gastric adenocarcinoma including a focus on hereditary diffuse gastric cancer (HDGC). Joseph Kim, MD of Stony Brook University discussed a systematic approach to minimally invasive gastrectomy for cancer. Joyce Wong, MD of Pennsylvania State University discussed the role for cytoreductive surgery (CRS) and HIPEC for gastric adenocarcinoma.

CONCLUSIONS

This review provides gastrointestinal surgeons with a concise update on the current surgical management of gastric tumors.

Ileal GIST presenting with bacteremia and liver abscess: A case report and review of literature

INTRODUCTION

Small intestine gastrointestinal stromal tumors can infrequently present with intra-abdominal abscess, perforation, obstruction or fistula. Tumor-small intestine fistula is a rare phenomenon and occurs as a result of GISTs' propensity to cause mucosal ulceration. This allows bacteria from the gut to gain access to the systemic circulation and predisposes the patient to bacteremia and pyogenic liver abscess.

PRESENTATION OF CASE

We present a case of a 63-year-old female whose initial symptoms included fever, nausea, vomiting and right upper quadrant pain. Radiologic studies revealed a liver lesion and an intra-abdominal mass containing oral contrast, suggesting involvement of the gastrointestinal tract. She was found to have a liver abscess, Streptococcus anginosus bacteremia and an ileal GIST that formed a fistula between the tumor and small intestine. We performed a surgical resection of the tumor and percutaneous drainage of the liver abscess. Imatinib was initiated post operatively and she experienced no recurrence, as demonstrated by a surveillance computed tomography scan at 12 months.

CONCLUSION

Findings of a liver lesion in association with a small intestine GIST should raise concern for both metastatic disease and a possible infectious complication such as a pyogenic liver abscess. If a member of the Streptococcus milleri group is isolated in blood cultures, a consideration for gastrointestinal malignancy is imperative. This case report reviews a rare presentation of an ileal GIST with tumor-intestinal fistula, complicated by liver abscess and Streptococcus anginosus bacteremia.

Prognostic role of the primary tumour site in patients with operable small intestine and gastrointestinal stromal tumours: a large population-based analysis

The postoperative recurrence risk of gastrointestinal stromal tumour (GIST) should be estimated when considering adjuvant systemic therapy. Previous studies in the literature have suggested that small intestinal GISTs are more aggressive than gastric GISTs. We assessed the prognostic role of the primary tumour site in patients with operable GIST to compare the outcomes of gastric and small intestinal GISTs over a decade of treatment. The Surveillance, Epidemiology, and End Results (SEER) database was queried for cases of gastric and small intestinal GISTs between 2004 and 2014 using the GIST-specific histology code (ICD-O-3 code 8936), and only patients with tissues sampled by surgical resection were selected for this study. Cancer-specific survival (CSS) and overall survival (OS) were compared between small intestinal and gastric GISTs using Cox regression analyses. GISTs were located in the stomach (n = 2594, 65%), duodenum (n = 228, 6%), and jejunum/ileum (n = 1176, 29%). The OS and CSS of patients with GISTs in the duodenum and jejunum/ileum were similar to those of patients with gastric GISTs in Cox regression analyses, except for the CSS of patients with tumour sizes 2.1-5 cm in diameter and ≤ 5 mitoses per 50 HPFs (HR 1.657; 95% CI 1.062-2.587, p = 0.026). Tumours sizes 2.1–5 cm in diameter and > 5 mitoses per 50 HPFs (HR 4.627; 95% CI 1.035-20.67, p = 0.045) in jejunal/ileal GIST locations had significantly worse CSS than did those in gastric GIST locations. In this large nationwide study, the primary tumour site was not an independent prognostic factor in patients with operable small intestinal and gastric GISTs.

Gastrointestinal Stromal Tumors

GI stromal tumors (GISTs) are neoplasms with a varying malignancy potential ranging from virtually indolent tumors to rapidly progressing cancers. GISTs occur throughout the intestinal tract, and most harbor an activating mutation in either KIT or platelet-derived growth factor A ( PDGFRA). Diagnosis is made using immunohistochemistry, but molecular testing with mutation analysis is paramount for selection of appropriate therapy. Most small GISTs are cured with surgery. Tyrosine kinase inhibitor (TKI) therapy has led to substantial improvements in survival, both for patients with localized GIST and those with advanced disease. Adjuvant therapy with imatinib benefits patients with a high risk of recurrence, with studies suggesting most benefit with at least 3 years of therapy. Neoadjuvant imatinib therapy should be considered for patients requiring extensive surgery, aiming at shrinking the tumor to allow organ preservation and less extensive surgery. The following three TKIs have been approved for the management of advanced disease: imatinib, sunitinib, and regorafenib; imatinib is usually the best tolerated of the three and the standard first-line treatment. TKIs benefit the majority of patients with advanced GIST but have no or limited efficacy in patients with the PDGFRA D842V mutation or patients with GIST lacking KIT and PDGFRA mutations. Surgery, the mainstay of primary tumor management, also plays a role in the advanced disease setting for selected patients, as do some other approaches such as palliative radiation therapy. Research continues to identify novel therapies, in particular effective agents to treat TKI-refractory disease.

Adjuvant imatinib for patients with high-risk gastrointestinal stromal tumors: a retrospective cohort study

The duration of adjuvant imatinib for high-risk patients with gastrointestinal stromal tumors (GISTs) is still controversial. Therefore, we retrospectively analyzed the data of high-risk patients with GISTs to investigate the appropriate duration. All 185 patients were divided into 4 groups: <1 year (Group A), 1–2 years (Group B), 2–3 years (Group C) and >3 years (Group D). The mean recurrence-free survival (RFS) in Groups A, B, and C were 44.3, 62.1, and 86.8 months, respectively (P < 0.001); the mean overall survival (OS) in Groups A, B and C was 75.2, 88.1, and 94.7 months, respectively (P = 0.009). The 5-year RFS in Groups A, B, C, and D was 15%, 26%, 83%, and 100%, respectively (P < 0.001); and the 5-year OS was 64%, 88%, 88%, and 100%, respectively (P < 0.001). The greatest impact on unfavorable outcomes was the tumor mitotic rate (HR, 2.01, 95% CI, 1.38–2.94; P < 0.001). Duration of adjuvant imatinib was the only favorable factor (HR, −0.95, 95% CI, 0.93–0.97; P < 0.001). For high-risk patients with high tumor size or mitotic rate, or non-gastric GISTs, we recommend that more than 3 years of adjuvant imatinib is feasible.

Characterization of malignant gastrointestinal stromal tumors-a single center experience

Background

The recurrence rate, related to the unpredictable behavior of gastrointestinal stromal tumors (GISTs), continues to be a major topic of investigation, since no actual risk evaluation scales have proven to be exceedingly effective in predicting prognosis. We therefore focus in this study on investigating the predictive variables of disease recurrence.

Methods

Between September 2004 and January 2011, 34 patients, 18 males and 16 females with a median age of 62 (range, 27-87) years, underwent operations for primary, localized and advanced GISTs. Immunohistochemical profile, KIT and the platelet-derived growth factor receptor-alpha (PDGFR-α) gene mutations, tumor size, tumor site, mitotic index, synchronous tumors, adjuvant therapy, symptoms and gender were considered and analyzed as predictive variables. The receiver operating characteristic (ROC) analysis was used to determine the optimal cut-off value for tumor dimension to predict recurrence.

Results

The median follow-up (FU) was 20 months (range, 6-86 months). A first-line adjuvant therapy was performed in nine patients. Disease relapse occurred in five cases. The tumor size and the mitotic index were the strongest predictive factors (P<0.001). The optimal maximum value for the tumor size was 7 cm [area under the curve (AUC) =0.955].

Conclusions

In light of the most recent evidence, a tumor size of 7 cm should be considered the threshold value for malignancy, and smaller GISTs with low mitotic counts as tumors with a low-grade risk.

Latest advances in adult gastrointestinal stromal tumors

Gastrointestinal stromal tumors (GISTs) are the most common GI tract mesenchymal tumors. GIST patients are optimally managed by a precision medicine approach. Herein, we discuss the latest advances in precision medicine and ongoing clinical trials relevant to GIST. Circulating tumor DNA for detection of mutational changes could replace tissue biopsies and radiographic imaging once validated. Most GISTs are KIT/PDGFRα mutated, and despite the good clinical response to imatinib, treatment is generally not curative, more often due to secondary mutations. New mechanisms to bypass this resistance by inhibiting KIT downstream pathways and by targeting multiple KIT or PDGFRα mutations are being investigated. Immunotherapy for GIST patients is in its infancy. These approaches may lead to more effective, less toxic therapies.

Recent advances in managing gastrointestinal stromal tumor

Constitutive activating mutations in KIT and platelet-derived growth factor receptor α ( PDGFRα) are heavily involved in the pathobiology of gastrointestinal stromal tumors (GISTs). This disease has served as an effective "proof-of-concept" model for targeting gain-of-function kinase mutations in cancer. This review discusses the current standard of care in terms of pharmacotherapy in the management of localized and metastatic GISTs.

Principles of Kinase Inhibitor Therapy for Solid Tumors

OBJECTIVE

We aimed to identify key principles of targeted therapy of protein kinases and their application to the management of solid tumors.

BACKGROUND

Concurrent advances in tumor genomic analysis and molecular inhibitor development have dramatically impacted the diagnosis and treatment of solid tumors, and common themes regarding the use of kinase inhibitors are developing.

METHODS

The list of kinase inhibitors that have been approved by the US Food and Drug Administration was reviewed and articles related to the agents were searched in the PubMed database up until December 2015. We included pivotal, randomized controlled phase 2 and 3 trials, and also pertinent preclinical studies.

RESULTS

Small molecule inhibitors targeted against driver kinases, overactive in selected subsets of solid tumors, elicit improved response rates and survival compared with standard chemotherapy. Disease control has been proven in the metastatic and, to a limited extent, the adjuvant setting. However, tumor eradication is rare, and duration of treatment response is limited by the development of drug resistance.

CONCLUSIONS

Kinase inhibitors induce response in diverse types of solid tumors. Although the agents are often effective in defined molecular subsets, cure is rare and resistance is common. This broad review provides rationale for further investigation of multimodality therapy combining kinase inhibitors with additional systemic and local therapies, including surgery.

How best to manage gastrointestinal stromal tumor

Gastrointestinal stromal tumors (GISTs) are rare but most common nonepithelial tumor of gastrointestinal tract. They are often found incidentally on computed tomography and endoscopic investigations. Increasing knowledge of the pathogenesis of GISTs and the advent of tyrosine kinase inhibitors revolutionized the management of GISTs. The newer advanced endoscopic techniques have challenged the conventional surgery although the true efficacy and safety of endoscopic approach is not clear at this time. This review article focuses on pathogenesis, diagnosis and management of GISTs.

GEIS guidelines for gastrointestinal sarcomas (GIST)

Gastrointestinal stromal sarcomas (GISTs) are the most common mesenchymal tumours originating in the digestive tract. They have a characteristic morphology, are generally positive for CD117 (c-kit) and are primarily caused by activating mutations in the KIT or PDGFRA genes(1). On rare occasions, they occur in extravisceral locations such as the omentum, mesentery, pelvis and retroperitoneum. GISTs have become a model of multidisciplinary work in oncology: the participation of several specialties (oncologists, pathologists, surgeons, molecular biologists, radiologists…) has forested advances in the understanding of this tumour and the consolidation of a targeted therapy, imatinib, as the first effective molecular treatment in solid tumours. Following its introduction, median survival of patients with advanced or metastatic GIST increased from 18 to more than 60months. Sunitinib and Regorafenib are two targeted agents with worldwide approval for second- and third-line treatment, respectively, in metastatic GIST.

Urgency surgical treatment for duodenal GISTs: analysis of aged patients and review of the literature

INTRODUCTION

Gastrointestinal stromal tumours (GISTs) are the most common mesenchymal neoplasms (85%) of the gastrointestinal (GI) tract; duodenal GISTs constitute 3-5% of all GISTs and represent 10-30% of all malignant tumours of the duodenum. Rarely, patients present severe bowel obstruction, perforation or severe bleeding. The radical resection with complete removal of the tumour remains the main therapeutic approach. We performed a local resection in patients with suspected GIST admitted for emergency treatment for GI bleeding.

CASES

We present three cases of patients admitted for GI bleeding. The cause could be a GIST bleeding. In all cases, local resection was performed without a pancreaticoduodenectomy. Histological examination on surgical preparations showed that in two cases it was a GIST and in one case, it was a leiomyoma.

DISCUSSION

Surgery remains the treatment of choice in the case of a GIST primitive without evidence of metastases, even for patients who are hospitalized for a bleeding emergency. Wide resections are not needed; it is important to remove completely the disease. In the case of duodenal GIST, it is important to get negative margins near the head of the pancreas, and this could take a PD. According to our experience and to the literature review, we believe that if the duodenal papilla or the periampullary region is not interested, you must perform a local resection. This is also because non-malignant tumours may present as GISTs and in these cases it is not recommended to run a PD.

CONCLUSION

The treatment of choice for duodenal GISTs is complete surgical resection with negative resection margins. When the papilla or the periampullary region is involved we choose to perform pancreaticoduodenectomy; otherwise it is better to perform a local resection. In fact, local resection has lower morbidity and mortality, with a comparable outcome.

Management of Gastrointestinal Stromal Tumors

Gastrointestinal stromal tumors had the reputation for poor outcomes because of their lack of response to nonsurgical interventions. The discovery of gain-of-function mutations involving receptor tyrosine kinase growth factor receptors altered the biological understanding and management. Beginning in 2000, management of these tumors has changed dramatically because of the availability of tyrosine kinase inhibitors. The role of surgery continues to be refined. This article reviews how surgery and systemic therapy are being used, incorporating definitions of risk. Decisions on how to treat a patient is based on the risk of progression, pathologic characteristics, and tumor location.

Gastrointestinal stromal tumours (GISTs): an insight into clinical practice with review of literature

BACKGROUND

Gastrointestinal stromal tumours (GISTs) are rare mesenchymal tumours of the gastrointestinal tract. We retrospectively reviewed the clinical management of all patients with GIST presenting to a regional multidisciplinary upper gastrointestinal cancer group in the north of England.

METHODS

Clinical, pathological, immunohistochemical treatment strategies, follow-up and outcome data on all patients with GIST between 2007 and 2012 were reviewed. Tumours were categorised by risk according to the National Institutes of Health (NIH) and AFIP models.

RESULTS

36 (85.7%) of 42 tumours were located in the stomach, 5 (11.9%) in the small intestine and 1 (2.4%) in the oesophagus. Median age of patients was 68 (range 43-91) years. 24 patients (57.1%) were female. Tumour size ranged from 1.0  to 12.7 cm with mean size of 5.46 cm. Metastasis was present in 19 (45.2%) patients at diagnosis with distant metastases in 12 patients. Liver was the most common site of metastases. Histology and immunohistochemical analysis was available in 32 (76.2%) patients. Most common histology was spindle cell morphology 17/32 (53.1%) followed by epithelioid 9/32 (28.1%) and mixed morphology 5/32 (15.6%). The positive rate for KIT protein (CD117) was 90.6%, while that for CD34 was 75.0%. 12/25 (48.0%) and 8/23 (34.8%) patients were categorised as high risk as per NIH and AFIP risk scores, respectively. 23/42 (54.8%) patients underwent surgical resection, after which 5/23 (21.7%) had adjuvant imatinib therapy. Imatinib was given as primary therapy in 14/42 (33.3%) patients.

CONCLUSIONS

Surgery alone may not be a curative treatment for GISTs. Targeted therapy with imatinib may play an important role in the treatment of GISTs. Further risk categorisation models may be needed to evaluate GIST behaviour and prognosis.

Chinese consensus guidelines for diagnosis and management of gastrointestinal stromal tumor

In order to further promote the standardization of diagnosis and treatment of gastrointestinal stromal tumor (GIST) in China, the members of Chinese Society of Clinical Oncology (CSCO) Expert Committee on GIST thoroughly discussed the key contents of the consensus guidelines, and voted on the controversial issue. In final, the Chinese consensus guidelines for the diagnosis and management of GIST (2017 edition) was formed on the basis of 2013 edition consensus guidelines, which is hereby announced. The consensus included the pathological diagnosis, recurrence risk classification evaluation, targeted agent therapy, surgery and principles of surveillance of GIST.

Update on Gastrointestinal Stromal Tumors for Radiologists

The management of gastrointestinal stromal tumors (GISTs) has evolved significantly in the last two decades due to better understanding of their biologic behavior as well as development of molecular targeted therapies. GISTs with exon 11 mutation respond to imatinib whereas GISTs with exon 9 or succinate dehydrogenase subunit mutations do not. Risk stratification models have enabled stratifying GISTs according to risk of recurrence and choosing patients who may benefit from adjuvant therapy. Assessing response to targeted therapies in GIST using conventional response criteria has several potential pitfalls leading to search for alternate response criteria based on changes in tumor attenuation, volume, metabolic and functional parameters. Surveillance of patients with GIST in the adjuvant setting is important for timely detection of recurrences.

Comparison of Different Risk Classification Systems in 558 Patients with Gastrointestinal Stromal Tumors after R0-Resection

Background: Due to adjuvant treatment concepts for patients with R0-resected gastrointestinal stromal tumors (GIST), a reproducible and reliable risk classification system proved of utmost importance for optimal treatment of patients and prediction of prognosis. The aim of this study was to reevaluate the impact of five widely-applied and well-established GIST risk classification systems (i.e., scores by Fletcher, Miettinen, Huang, Joensuu, and TNM classification) on a series of 558 GIST patients with long-term follow-up after R0 resection. Methods: Tumor size, mitotic count and site were used in variable combination to predict high- and low risk patients by the use of the five risk classification models. For survival analyses disease-specific survival, disease-free survival and overall-survival were investigated. Patients with initial metastatic disease or incompletely resectable tumors were excluded. Results: All GIST classification models distinguished well between patients with high-risk and low-risk tumors and none of the five risk systems was superior to predict patient outcome. The models showed significant heterogeneity. There was no significant difference between the different risk-groups regarding overall-survival. Subdivision of GIST patients with very low- and low-risk appeared to be negligible. Conclusions: Currently applied GIST risk classification systems are comparable to predict high- or low-risk patients with initial non-metastatic and completely resected GIST. However, the heterogeneity of the high-risk group and the absence of differences in overall survival indicate the need for more precise tumor- and patient-related criteria for better stratification of GIST and identification of patients who would benefit best from adjuvant tyrosine kinase inhibitor therapy.

Gastric and small intestine gastrointestinal stromal tumors: Do outcomes differ?

BACKGROUND AND OBJECTIVES

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors of the gastrointestinal tract. Previous literature has suggested that small intestine GISTs are more aggressive than gastric GISTs. Our primary objective was to compare the outcomes of gastric and small intestine GISTs in the decade after approval of imatinib for treatment.

METHODS

The SEER database was queried for cases of gastric and small intestine GIST between the years 2002 and 2012, using the ICD-O-3 histology code 8936. Survival analysis was performed using generalized gamma models for time to cause-specific mortality (CSM).

RESULTS

CSM was 14.0% for the 3,759 gastric GIST patients and 14.3% for the 1,848 small intestine GIST patients. Five-year survival was 82.2% and 83.3% for gastric and small intestine patients, respectively. The number of diagnosed cases of GIST increased over the course of this study, especially for tumors <5 cm in size and in patients over age 50 years.

CONCLUSIONS

In this large nation-wide study, we found that patients with gastric and small intestine GISTs had similar outcomes, in contrast to previous reports. The diagnosis of GIST has significantly increased in the last decade, which may reflect the increased recognition of this entity and frequent use of imaging. J. Surg. Oncol. 2017;115:351-357. © 2016 Wiley Periodicals, Inc.

Pediatric/"Wildtype" gastrointestinal stromal tumors

Pediatric/"Wildtype" gastrointestinal stromal tumor (P/WT-GIST) is a rare cancer, distinct and markedly different from the phenotype found predominantly in older patients (adult, non-wildtype GIST). Having a different molecular signature, it is not responsive to standard adjuvant therapies utilized in adult GIST, and surgery remains the only effective cure. However, even with presumed complete resections in patients with localized disease at presentation, recurrence rates are high. Furthermore, it is an indolent cancer that can persist for decades, and treatment strategies must balance the possible morbid risks of intervention with the reality of preserving quality of life in the interim. Effective adjuvant therapies remain elusive, and research is critically needed to identify both targets and drugs for treatment consideration.

Combined Therapy of Gastrointestinal Stromal Tumors

Radical surgery is the mainstay of therapy for primary resectable, localized gastrointestinal stromal tumors (GIST). Nevertheless, approximately 40% to 50% of patients with potentially curative resections develop recurrent or metastatic disease. The introduction of imatinib mesylate has revolutionized the therapy of advanced (inoperable and/or metastatic) GIST and has become the standard of care in treatment of patients with advanced GIST. This article discusses the proper selection of candidates for adjuvant and neoadjuvant treatment in locally advanced GIST, exploring the available evidence behind the combination of preoperative imatinib and surgery.

Application of an individualized operative strategy for wedge resection of gastric gastrointestinal stromal tumors: Effectiveness for tumors in difficult locations

BACKGROUND

There is some concern that wedge resection of gastric gastrointestinal stromal tumors is not feasible in certain anatomic locations, such as the cardia or antrum. We sought to review our experience with treatment of gastric gastrointestinal stromal tumors with a particular focus on nonanatomic wedge resections in these challenging locations.

METHODS

Patients undergoing resection of gastrointestinal stromal tumors from 2000-2014 at the Montreal General Hospital were identified from a prospectively collected database, and outcomes were tabulated. An individualized operative strategy was used to guide resection based on tumor location, size, and characteristics. Disease-free survival and overall survival analyzed using the Kaplan-Meier method. Data are presented as median (range).

RESULTS

We identified 59 patients who underwent operative resection for gastric gastrointestinal stromal tumors. Tumor location was fundus/body/greater curvature in 35 (59%) patients, lesser curvature in 8 (14%) patients, antrum in 8 (14%) patients, and cardia in 8 (14%) patients. Median tumor size was 4.5 cm (1.4-25 cm). The majority of cardia and antral lesions were removed with wedge resections (14/16, 87%). For cardial and antral tumors, on-table gastroscopy was used to guide the operative approach and prevent narrowing of the Gastroesophageal junction or pylorus in all patients undergoing wedge resection. Negative pathologic margins were achieved in all patients. The 5-year disease-free survival was 91% and 5-year overall survival was 95%.

CONCLUSION

When selected appropriately, and under the guidance of on-table gastroscopy, laparoscopic nonanatomic wedge resection can be performed successfully in the majority of cases, even for gastrointestinal stromal tumors near the GEJ or pylorus, with excellent oncologic outcomes.

Blood-Based Biomarkers Are Associated with Disease Recurrence and Survival in Gastrointestinal Stroma Tumor Patients after Surgical Resection

Background

Inflammatory blood count biomarkers may improve recurrence risk stratification and inform long-term prognosis of cancer patients. Here, we quantify the prognostic impact of blood-based biomarkers on recurrence risk and long-term survival in a large cohort of gastrointestinal stroma tumor (GIST) patients after curative surgery.

Methods

One-hundred-forty-nine consecutive GIST patients were followed-up for a median period of 4.8 years. Local recurrence, distant metastasis, and death occurred in 9, 21, and 31 patients, respectively. Time-to-event and competing risk analysis were applied to study the association between haemoglobin (Hb) level, white blood cell count (WBC), neutrophil/lymphocyte ratio (NLR), derived NLR (dNLR), lymphocyte/monocyte ratio (LMR), and platelet/lymphocyte ratio (PLR) with risk of local or distant recurrence (RR), recurrence free survival (RFS), and overall survival (OS).

Results

A low Hb (p = 0.029), and elevations in the parameters WBC (p = 0.004), NLR (p = 0.015) and dNLR (p = 0.037) were associated with a poor OS in GIST patients in multivariate analysis. Moreover, a low Hb (p = 0.049) and an elevated WBC (p = 0.001), NLR (p = 0.007), dNLR (p = 0.043) and PLR (p = 0.024) were independently associated with decreased RFS after adjusting for Miettinen score. However, only an increase of dNLR/NLR showed a significant association to higher RR (p = 0.048). Inclusion of NLR or PLR to Miettinen risk score did not reasonably improve the clinical risk prediction of 2-year RFS.

Conclusion

Low Hb, elevated WBC, elevated dNLR, and elevated PLR are independent prognostic factors for a worse clinical outcome in GIST patients after curative resection.

Treatment failure prediction for head-and-neck cancer radiation therapy

PURPOSE

Treatment outcome prediction is an important emerging topic in oncologic care. To support radiation oncologists on their decisions, with individualized, tailored treatment regimens increasingly becoming the standard of care, accurate tools to predict tumour response to treatment are needed. The goal of this work is to identify the most determinant factor(s) for treatment response aiming to develop prediction models that robustly estimate tumour response to radiation therapy in patients with head-and-neck cancer.

PATIENTS AND METHODS

A population-based cohort study was performed on 92 patients with head-and-neck cancer treated with radiation from 2007 until 2014 at the Portuguese Institute of Oncology of Coimbra (IPOCFG). Correlation analysis and multivariate binary logistic regression analysis were conducted in order to explore the predictive power of the considered predictors. Performance of the models is expressed as the area under the curve (AUC) of the receiver operating characteristics (ROC) curve. A nomogram to predict treatment failure was developed.

RESULTS

Significant prognostic factors for treatment failure, after multivariate regression, were older age, non-concomitant radiation therapy and larger primary tumour volume. A regression model with these predictors revealed an AUC of .78 for an independent data set.

CONCLUSION

For patients with head-and-neck cancer treated with definitive radiation, we have developed a prediction nomogram based on models that presented good discriminative ability in making predictions of tumour response to treatment. The probability of treatment failure is higher for older patients with larger tumours treated with non-concomitant radiation.

Is multivisceral resection in locally advanced gastrointestinal stromal tumours an acceptable strategy?

BACKGROUND

Gastrointestinal stromal tumours (GISTs) represent the most common mesenchymal tumour of the gastrointestinal tract. Although the efficacy of targeted therapy cannot be over-emphasized, surgery remains the only curative primary treatment for patients with localized disease. The median size of GIST at diagnosis is approximately 5-7 cm; however, it is not uncommon for tumours to be as large as 30-40 cm and involving multiple viscera.

METHODS

Data were retrospectively collected from patients with GISTs treated at the Singapore General Hospital and the National Cancer Centre Singapore over a 15-year period. Standard resection of GIST without any additional organ removal was termed as a single organ resection (SOR). If the tumour was adjacent to another organ, necessitating the removal of more than one organ, the procedure was defined as a multivisceral resection (MVR). We aim to evaluate the role of MVR in the management of large GISTs.

RESULTS

A total of 187 patients underwent curative surgery for GIST between January 2000 and January 2014. Of the 187 patients, 40 (21%) underwent MVR whereas 147 (79%) had SOR. Patients in the MVR group had significantly larger tumour sizes (P < 0.001) yet R0 and R1 resection was achieved in all patients, and no intra-peritoneal rupture was reported. On comparison of MVR versus SOR groups, there was no significant difference in in-hospital morbidity and mortality.

CONCLUSION

MVR may be required to achieve negative margins in patients with large GISTs, and can be performed with acceptable morbidity and mortality.

Prognosis and management of adult wild type gastrointestinal stromal tumours (GISTs): A pooled analysis and review of literature

A pooled review was performed to determine survival in adult WT GIST (Wild Type GastroIntestinal Stromal Tumours) and compare the same with pediatric WT GISTs. Electronic databases were searched using the terms "Wild type" AND "GIST". Eighty-two adult patients from 14 studies were included in the pooled analysis. Cumulative survival was greater than 50% in both age groups, hence medial survival could not be computed. Mean survival in adults was 15.7 years ± 0.78 and in children was 18.8 years ± 1.3 (p = 0.241). Median disease free survival in adults was 10 years while 5-year overall survival was 88%. There was no statistically significant difference in the survival between the two groups (p = 0.241). Overall survival in adults with WT GISTs is favourable compared to other adult GIST subtypes likely reflects a common molecular pathway similar to pediatric GIST.

Evaluation of Gold's nomogram for predicting recurrence-free survival in gastrointestinal stromal tumors in Indian patients

Gold described a nomogram for prediction of recurrence-free survival (RFS) after surgery for gastrointestinal stromal tumors (GIST). This retrospective study was intended to evaluate the utility of this nomogram for predicting a 2-year RFS in our patients. Twenty-eight consecutive eligible patients from January 2009 to January 2013 who underwent R0 resection and had histopathologically proven GIST were included in the study. Nomogram predicted RFS was compared with observed RFS in four groups as in the National Institutes of Health (NIH)-Fletcher classification. Calibration was assessed by plotting the predicted probabilities of RFS against the actual outcome. For validation of the nomogram, the graph obtained should be closer to the 45-degree line. The observed overall 2-year RFS was 85.7 % (24 patients). Four patients had recurrence within 2 years. The observed RFS was 87.5 %, 77.8 %, 90 %, and 100 % in the high, intermediate, low, and very low risk groups, respectively. The nomogram predicted the 2-year RFS was 40 %, 84.8 %, 88.6 %, and 90 % for high, intermediate, low, and very low risk groups, respectively. Thus, the predicted probabilities of the 2-year RFS in intermediate, low, and very low risk groups were similar to the observed outcomes. However, for the high risk group, the observed RFS was better than predicted RFS. This variation in the high risk group may be due to the use of adjuvant imatinib in our study.

Surgical Treatment of Gastrointestinal Stromal Tumors Located in the Stomach in the Imatinib Era

BACKGROUND

Imatinib has changed the treatment of gastrointestinal stromal tumors (GISTs). Preoperative imatinib treatment can be administered to patients with locally advanced disease to reduce the risk of incomplete resection, tumor spill, and lessen the extent of resection. In metastatic GIST, surgery follows imatinib in responding patients with resectable disease. In this study, the outcome of surgically treated patients with a gastric GIST with and without preoperative imatinib was investigated.

METHODS

Patients surgically treated for a gastric GIST at our institute between 1999 and 2011 were included. Patient data were retrieved from a prospectively maintained database.

RESULTS

A consecutive series of 47 patients was identified: 17 patients were treated with primary surgery (group 1) and 30 patients received imatinib before surgery (group 2). Preoperative imatinib led to a 33% reduction in tumor size. All patients in group 1 and 23 patients (77%) in group 2 had a complete resection (R0) without tumor spill. At a median follow-up of 30 months, 4 patients in group 2 had died of GIST. In these 4 patients, either the resection had been irradical or tumor spill had occurred, and 3 of them had radiologic progressive disease at the time of surgery.

CONCLUSIONS

In this surgical series of gastric GIST patients, preoperative imatinib led to a major reduction in tumor size. Irradical resection, tumor spill, and progressive disease at the time of surgery were associated with poor prognosis.

Individualized nomogram improves diagnostic accuracy of stage I-II gallbladder cancer in chronic cholecystitis patients with gallbladder wall thickening

BACKGROUND

Early diagnosis of gallbladder cancer (GBC) can remarkably improve the prognosis of patients. This study aimed to develop a nomogram for individualized diagnosis of stage I-II GBC in chronic cholecystitis patients with gallbladder wall thickening.

METHODS

The nomogram was developed using logistic regression analyses based on a retrospective cohort consisting of 89 consecutive patients with stage I-II GBC and 1240 patients with gallbladder wall thickening treated at one biliary surgery center in Shanghai between January 2009 and December 2011. The accuracy of the nomogram was validated by discrimination, calibration and a prospective cohort treated at another center between January 2012 and December 2014 (n=928).

RESULTS

Factors included in the nomogram were advanced age, hazardous alcohol consumption, long-standing diagnosed gallstones, atrophic gallbladder, gallbladder wall calcification, intraluminal polypoid lesion, higher wall thickness ratio and mucosal line disruption. The nomogram had concordance indices of 0.889 and 0.856 for the two cohorts, respectively. Internal and external calibration curves fitted well. The area under the receiver-operating characteristic curves of the nomogram was higher than that of multidetector row computed tomography in diagnosis of stage I-II GBC (P<0.001).

CONCLUSION

The proposed nomogram improves individualized diagnosis of stage I-II GBC in chronic cholecystitis patients with gallbladder wall thickening, especially for those the imaging features alone do not allow to confirm the diagnosis.

A gastrointestinal stromal tumor at the esophagogastric junction successfully treated by laparoscopic wedge resection with seromuscular layer dissection: a case report

Herein, we report a case of a gastrointestinal stromal tumor (GIST) at the esophagogastric junction (EGJ) that was successfully treated by a laparoscopic wedge resection (LWR) after dissection of the seromuscular layer around the tumor to prevent postoperative deformities and stenosis of the EGJ. Subsequently, the abdominal esophagus was wrapped by the gastric fornix according to Dor's method in order to prevent reflux esophagitis after surgery.A 71-year-old female patient was admitted with a diagnosis of a GIST (23 × 20 × 20 mm) at the EGJ. We performed the abovementioned operation.Gastroduodenal endoscopic examination revealed no deformity or stenosis of the EGJ at 6 months after the operation. The patient has not experienced any reflux symptoms. Tumor recurrence was not noted 26 months after the operation.This procedure is useful in preventing the deformity and stenosis of the EGJ as well as postoperative reflux esophagitis.

The predictive value of preoperative 18F-fluorodeoxyglucose PET for postoperative recurrence in patients with localized primary gastrointestinal stromal tumour

OBJECTIVES

To assess the potential value of preoperative ¹⁸F-FDG PET to predict postoperative recurrence of solitary localized primary gastrointestinal stromal tumour (GIST) after radical resection.

METHODS

A total of 46 patients with primary GIST who received preoperative ¹⁸F-FDG PET and underwent complete resection without neoadjuvant therapy were retrospectively studied. PET findings, including ring-shaped uptake and intense uptake, were compared with Joensuu risk grades using Fisher's exact test. The prognostic value of the preoperative clinico-imaging variables-age ≥60 years, male, ring-shaped uptake, intense uptake, tumour size >5 cm, heterogeneous CT attenuation and lower gastrointestinal origin-and Joensuu high risk for recurrence-free survival was evaluated using log-rank test and multivariate Cox regression analysis.

RESULTS

Ring-shaped uptake and intense uptake were significantly associated with Joensuu high risk. Univariate analysis showed that ring-shaped uptake, intense uptake, size >5 cm and Joensuu high risk were significantly associated with inferior recurrence-free survival. Multivariate analysis showed that ring-shaped uptake (P = 0.004) and Joensuu high risk (P = 0.021) were independent adverse prognostic factors of postoperative recurrence.

CONCLUSIONS

Ring-shaped uptake on preoperative ¹⁸F-FDG PET may be a potential predictor of postoperative tumour recurrence of localized primary GISTs.

KEY POINTS

• Clinical course of resectable solitary localized primary GISTs varies widely. • Ring-shaped uptake is an independent adverse prognostic factor of postoperative recurrence. • Preoperative ¹⁸ F-FDG PET may help predict postoperative recurrence of GISTs.

Relationship between imatinib trough concentration and outcomes in the treatment of advanced gastrointestinal stromal tumours in a real-life setting

BACKGROUND

Imatinib has dramatically improved the prognosis of advanced gastrointestinal stromal tumours (GISTs). Clinical trial data showed that patients with trough imatinib plasma concentrations (Cmin) below 1100 ng/ml (quartile 1) had shorter time to progression, but no threshold has been defined. The main objective of this study was to investigate in advanced GIST whether a Cmin threshold value associated with a longer progression-free survival (PFS) could be specified. This would be the first step leading to therapeutic drug monitoring of imatinib in GIST.

PATIENTS AND METHODS

Advanced GIST patients (n=96) treated with imatinib 400 mg/d (41 stomach, 34 small bowel, and 21 other primary site localisations) were prospectively included in this real-life setting study. Routine plasma level testing imatinib (Cmin) and clinical data of were recorded prospectively.

RESULTS

Small bowel localisation was associated with an increased relative risk of progression of 3.09 versus stomach localisation (p=0.0255). Mean Cmin (±standard deviation) was 868 (±536) ng/ml with 75% inter-individual and 26% intra-patient variability. A Cmin threshold of 760 ng/ml defined by log-rank test was associated with longer PFS for the whole population (p=0.0256) and for both stomach (p=0.043) and small bowel (p=0.049) localisations when analysed separately. Multivariate Cox regression analysis found that Cmin above 760 ng/ml was associated with 65% reduction risk of progression (p=0.0271) in the whole population independently of the anatomical localisation.

CONCLUSION

Concentration of imatinib significantly influences duration of tumour control treatment in GIST patients with a Cmin threshold of 760 ng/ml associated with prolonged PFS in real-life setting.

The standard diagnosis, treatment, and follow-up of gastrointestinal stromal tumors based on guidelines

Although gastrointestinal stromal tumors (GISTs) are a rare type of cancer, they are the commonest sarcoma in the gastrointestinal tract. Molecularly targeted therapy, such as imatinib therapy, has revolutionized the treatment of advanced GIST and facilitates scientific research on GIST. Nevertheless, surgery remains a mainstay of treatment to obtain a permanent cure for GIST even in the era of targeted therapy. Many GIST guidelines have been published to guide the diagnosis and treatment of the disease. We review current versions of GIST guidelines published by the National Comprehensive Cancer Network, by the European Society for Medical Oncology, and in Japan. All clinical practice guidelines for GIST include recommendations based on evidence as well as on expert consensus. Most of the content is very similar, as represented by the following examples: GIST is a heterogeneous disease that may have mutations in KIT, PDGFRA, HRAS, NRAS, BRAF, NF1, or the succinate dehydrogenase complex, and these subsets of tumors have several distinctive features. Although there are some minor differences among the guidelines--for example, in the dose of imatinib recommended for exon 9-mutated GIST or the efficacy of antigen retrieval via immunohistochemistry--their common objectives regarding diagnosis and treatment are not only to improve the diagnosis of GIST and the prognosis of patients but also to control medical costs. This review describes the current standard diagnosis, treatment, and follow-up of GISTs based on the recommendations of several guidelines and expert consensus.

Blood neutrophil-to-lymphocyte and platelet-to-lymphocyte ratios are independent prognostic factors for surgically resected gastrointestinal stromal tumors

BACKGROUND

Recent studies have demonstrated that the neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) are prognostic for various malignancies; however, there are limited data to date demonstrating their usefulness for gastrointestinal stromal tumors (GISTs). The aim of this study was to determine whether NLR and PLR are prognostic for GIST.

METHODS

Three hundred patients who underwent operative resection for primary localized GIST with preoperative results for neutrophil, platelet, and lymphocyte counts available were retrospectively reviewed. Optimal cutoff values for high NLR (≥ 3.0) and PLR (≥ 275) in predicting recurrence-free survival (RFS) were determined. Prognostic factors of RFS were determined using univariate and multivariate Cox regression analyses for the 266 patients who did not receive adjuvant imatinib.

RESULTS

On univariate analyses, tumor size, mitotic count, location, and both a high NLR and PLR were significant prognostic indicators of decreased RFS (hazard ratio [HR], 2.89 [95% CI; 1.609-5.179 P < .001] and HR, 3.572 [95% CI, 2.094-6.096; P < .001], respectively). On multivariate analyses, tumor size, mitotic count, tumor location, and both high NLR and PLR were independent prognostic factors of RFS in GIST. Both a high NLR and PLR were significant prognostic factors for GISTs within the National Institutes of Health (NIH) and Armed Forces Institute of Pathology (AFIP) high-risk categories. Addition of NLR or PLR to the NIH or AFIP improved the accuracy of these systems.

CONCLUSION

High NLR and PLR were independent prognostic factors of RFS in GIST. NLR and PLR would be useful as a preoperative prognostic tool and its incorporation into current prognostication systems improved their accuracy.

Global epidemiology of gastrointestinal stromal tumours (GIST): A systematic review of population-based cohort studies

BACKGROUND

Gastrointestinal stromal tumours (GISTs) are rare, yet the most common mesenchymal tumour within the digestive tract. Lack of diagnostic criteria and no specific code in the ICD system has prevented epidemiological evaluation except from overt malignant cases in the past. A global estimate of incidence and disease patterns has thus not been available.

METHODS

A systematic literature search of all available population-based studies on GIST published between January 2000 and December 2014 were reviewed. Descriptive epidemiological data are presented.

RESULTS

The search found 29 studies of more than 13,550 patients from 19 countries that reported sufficient data for regional or national population-based statistics. Age at diagnosis ranged from 10 to 100 years, with median age being mid 60s across most studies. Gender distribution was equal across studies. On average, 18% of patients had an incidental diagnosis (range from 5% to 40%). Anatomical location of primary tumour in 9747 GISTs demonstrated gastric location as the most frequent (55.6%) followed by small bowel (31.8%), colorectal (6.0%), other/various location (5.5%) and oesophagus (0.7%). Most studies reported incidence at 10-15 per million per year. Notably, lowest incidence was in China (Shanxi province) with 4.3 per million per year. Highest incidence rates were reported also from China (Hong Kong and Shanghai areas), and in Taiwan and Norway (Northern part), with up to 19-22 per million per year.

CONCLUSIONS

Epidemiology of GIST demonstrates some consistent features across geographical regions. Whether the reported extreme differences in incidence reflect real variation in population risk warrants further investigation.