The impact of incidental gastrointestinal stromal tumours on patients undergoing resection of upper gastrointestinal neoplasms

Characteristics of gastrointestinal stromal tumors associated to other tumors: Características de los tumores del estroma gastrointestinal asociados a otras neoplasias

INTRODUCTION

Our aim is to analyze the differences between sporadic gastrointestinal stromal tumors and those associated with other tumors.

METHODS

Retrospective cohort study including patients with diagnosis of gastrointestinal stromal tumors operated at our center. Patients were divided into two groups, according to whether or not they had associated other tumors, both synchronously and metachronously. Disease free survival and overall survival were calculated for both groups.

RESULTS

96 patients were included, 60 (62.5%) were male, with a median age of 66.8 (35-84). An association with other tumors was found in 33 cases (34.3%); 12 were synchronous (36.3%) and 21 metachronous (63.7%). The presence of mutations in associated tumors was 70% and in non-associated tumors 75%. Associated tumors were classified as low risk tumors based on Fletcher's stratification scale (p = 0.001) as they usually were smaller in size and had less than ≤5 mitosis per 50 HPF compared to non-associated tumors. When analyzing overall survival, there were statistically significant differences (p = 0,035) between both groups.

CONCLUSION

The relatively high proportion of gastrointestinal stromal tumors cases with associated tumors suggests the need to carry out a study to rule out presence of a second neoplasm and a long-term follow-up should be carried out in order to diagnose a possible second neoplasm. Gastrointestinal stromal tumors associated with other tumors have usually low risk of recurrence with a good long-term prognosis.

Gastrointestinal Stromal Tumors: Recurrence and Survival Analysis of 49 Patients

Background: Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumor originating from the gastrointestinal tract and have a broad spectrum of clinicopathological features affecting disease management regarding the treatment modalities. Methods: A retrospective study of 49 patients who underwent surgery for gastrointestinal tumors between 2008 and 2016 was conducted. Clinical, pathological, and immunohistochemical features of patients with and without recurrence were statistically analyzed. Results: Twenty-nine (59.1%) patients had gastric; 16 (32.6%) had small intestinal; 3 (6.1%) had mesenteric; and 1 (2.2%) had rectal GISTs. Microscopic tumor necrosis and tumor ulceration were also significant for disease recurrence (P = 0.005, P = 0.049). High-risk patients according to Miettinen's risk classification were more likely to develop a recurrence (P < 0.001). Additionally, high-grade tumors were also a risk factor for recurrence (P < 0.001). Ki-67 levels were available in 40 patients and the mean Ki-67 level was 16.8 in patients with recurrence, which was a significant risk factor in regression analysis (HR: 1.24, 95%, CI: 1.08-1-43). Five-year disease-free survival rates of non-gastric and gastric GISTs were 62.3% and 90%, respectively (P = 0.044). Conclusion: Larger tumors and higher mitotic rates are more likely to develop recurrence. High Ki-67 levels were also associated with recurrence.

The occurrence of gastrointestinal stromal tumors with second malignancies - Case series of a single institution experience

INTRODUCTION

Gastrointestinal stromal tumors (GISTs) may coexist with different types of malignancies, either synchronously or metachronously. The aim of this study was to characterize the clinical and histopathological features of GIST coexisting with other neoplasms.

METHODS

A retrospective analysis of 76 GISTs cases diagnosed at our institution between January 2003 and March 2020 was performed. A subgroup of cases with concomitant second malignancy was selected. The clinical and pathologic records were reviewed.

RESULTS

18 out of 76 patients (23.7%) with GISTs were diagnosed with the second neoplasms. In 11 cases GISTs were diagnosed metachronously to the second malignancy, whereas 7 cases of GIST were synchronous. The most common concomitant neoplasms were breast cancer and gastric cancer. The concomitant GIST were located mainly in small intestine (52.6%). 14 GISTs were classified as very low or low-risk (77.8%), 3 as moderate risk (16.7%) and 1 as high risk tumors (5.6%).

CONCLUSION

The coexistence of GIST with other malignancies may be more common, than it has been considered. As the most of concomitant GISTs occurs metachronously to the second malignancy, studying of this phenomenon requires a long-term follow-up.

Characteristics of Gastrointestinal Stromal Tumors incidentally discovered during abdominal surgery

BACKGROUND

Gastrointestinal Stromal Tumors (GISTs) are rare sarcomas with 5000 new cases arising in the United States each year. Despite their low incidence, general surgeons should be familiar with GISTs since a quarter of these neoplasms are encountered incidentally.

METHODS

A retrospective medical records review was conducted to create a database of all GISTs resected from January 2005 to May 2019. We isolated patients who had incidental discovery of GISTs intraoperatively or within final pathology. Characteristics of patient (Age, gender), index procedure (malignant vs. benign, elective vs. emergent) and tumor (location, size and mitotic rate) were analyzed.

RESULTS

A total 48 patients were incidentally discovered to have a GIST excised during index operation. The mean age of these patients was 62 years, with 27 females and 21 males. The primary location of tumors in descending frequency was stomach (30), small bowel (15), colon/rectum (2) and esophagus (1). The average size of all tumors was 1.2 cm, with the average size of the stomach, small bowel, colon/rectum and esophagus at 0.9 cm, 1.7 cm, 0.9 cm and 0.3 cm respectively. Mitotic rate was less than 5 mitosis per 50 HPF in 96% of patients. Incidental tumors were identified during both bariatric (13) and non-bariatric stomach surgery (8), colorectal surgery (14), hernia repair (4), ampullary/pancreatic surgery (5), esophageal surgery (2) liver surgery (1) and uterine surgery (1). Most incidental-GISTs were identified during elective surgery (81%, 39). Finally, 15 of the tumors were identified during surgery for other malignancies.

CONCLUSIONS

One quarter (25%) of the GISTs encountered at our academic community cancer center over a 15-year period were discovered incidentally. These tumors had less malignant characteristics overall and were likely cured with surgical resection.

Significance of Primary Malignant Tumors on the Outcome of Patients With Resected Gastrointestinal Stromal Tumors

AIM

This study aimed to clarify the significance of primary malignant tumors for the outcome of resected gastrointestinal stromal tumors (GISTs).

PATIENTS AND METHODS

The medical history, pathological findings and prognosis of 66 patients with GISTs resected at our institute between January 2003 and December 2018 were investigated retrospectively and compared statistically.

RESULTS

Among 66 patients with GISTs, 24 (36%) had concomitant malignant tumors. In an average study period of 57 months, one patient died from GIST, seven from other malignant tumors, and one from another disease. Only coexistence of GIST and other malignant tumors was recognized as a prognostic factor. Increasing age was significantly correlated with other malignant tumor in combination with GIST. When comparing patients with GIST alone and GIST with other malignant tumors, the latter showed significantly poorer prognosis.

CONCLUSION

Coexistence of other malignant tumors was commonly observed in patients with GIST, and was associated with poorer prognosis. This association should be carefully considered and monitored in patients with GISTs.

Cross-testing of major molecular markers indicates distinct pathways of tumorigenesis in gastric adenocarcinomas and synchronous gastrointestinal stromal tumors

Small subtype of the gastrointestinal stromal tumor (micro-GIST, MG) is usually asymptomatic and is frequently found incidentally in association with gastric adenocarcinoma (GAC). The background of this coincidence is still an open question. This study comprehensively characterized nine MGs and GACs present in the same surgical specimen by cross-testing the markers of the major pathogenetic pathways of both tumor types. All of the MGs were immunohistochemically positive for CD117/KIT, CD34, and DOG1. DOG1 was also detected in four GACs. Four MGs carried mutations in c-KIT (exons 9, 11, and 13) and two cases in PDGFRα (exon 18). None of the GACs carried activating mutations in c-KIT or PDGFRα. MMR immunopanel identified one GAC as microsatellite unstable tumor. No EBV-positive tumor was found. According to the TCGA molecular classification, one GAC was categorized in the MSI subgroup, three GACs in the genomically stable subgroup, and the rest into the chromosomal instability subgroup. Although a common carcinogenic effect cannot be ruled out, our data suggest a distinct molecular background in the evolvement of the synchronous MGs and GACs. The presence of a MG in gastric resection specimens may be indicative of the development of synchronous malignant tumors in or outside the stomach.

Incidental Gastrointestinal Stromal Tumors (GISTs) and Bariatric Surgery: A Review

The number of bariatric procedures has increased notably, with incidental findings such as gastrointestinal stromal tumors (GISTs) being observed in 2%. The number of studies dealing with incidental findings during bariatric surgery (BS), especially GISTs, is scarce. This review aims to summarize the evidence about GIST diagnosis during BS, and to establish recommendations for the management and follow-up of these patients. A systematic literature search from January 2000 to March 2020 was performed. Retrospective cohort studies, case series, case reports, reviews, and conference abstracts were considered eligible. The present systematic review focused on a descriptive analysis of the data included in the articles selected. The calculated incidence was 0.65%. A change in operative plan was observed in 5% of the cases. In 98% of the cases, GISTs were gastric, with a mean size of 10.3 mm. The mitotic index was < 5 in 99%. Accordingly, all patients were classified as having a very low or low risk of recurrence. R0 resection was achieved in 100% of cases. The incidence of GISTs in patients with MO submitted to BS is considerably higher than in the general population. The diagnosis is related to the depth of preoperative work, the exhaustiveness of the intraoperative examination, and the meticulousness of the histopathological analysis. Although GISTs have a low risk of recurrence and it was previously unnecessary to modify the surgical technique, we recommend that bariatric surgeons are aware of the diagnosis and management of incidental GISTs.

Synchronous resection of esophageal cancer and other organ malignancies: A systematic review

BACKGROUND

Neoplasms arising in the esophagus may coexist with other solid organ or gastrointestinal tract neoplasms in 6% to 15% of patients. Resection of both tumors synchronously or in a staged procedure provides the best chances for long-term survival. Synchronous resection of both esophageal and second primary malignancy may be feasible in a subset of patients; however, literature on this topic remains rather scarce.

AIM

To analyze the operative techniques employed in esophageal resections combined with gastric, pancreatic, lung, colorectal, kidney and liver resections and define postoperative outcomes in each case.

METHODS

We conducted a systematic review according to PRISMA guidelines. We searched the Medline database for cases of patients with esophageal tumors coexisting with a second primary tumor located in another organ that underwent synchronous resection of both neoplasms. All English language articles deemed eligible for inclusion were accessed in full text. Exclusion criteria included: (1) Hematological malignancies; (2) Head/neck/pharyngeal neoplasms; (3) Second primary neoplasms in the esophagus or the gastroesophageal junction; (4) Second primary neoplasms not surgically excised; and (5) Preclinical studies. Data regarding the operative strategy employed, perioperative outcomes and long-term outcomes were extracted and analyzed using descriptive statistics.

RESULTS

The systematic literature search yielded 23 eligible studies incorporating a total of 117 patients. Of these patients, 71% had a second primary neoplasm in the stomach. Those who underwent total gastrectomy had a reconstruction using either a colonic (n = 23) or a jejunal (n = 3) conduit while for those who underwent gastric preserving resections (i.e., non-anatomic/wedge/distal gastrectomies) a conventional gastric pull-up was employed. Likewise, in cases of patients who underwent esophagectomy combined with pancreaticoduodenectomy (15% of the cohort), the decision to preserve part of the stomach or not dictated the reconstruction method (whether by a gastric pull-up or a colonic/jejunal limb). For the remaining patients with coexisting lung/colorectal/kidney/liver neoplasms (14% of the entire patient population) the types of resections and operative techniques employed were identical to those used when treating each malignancy separately.

CONCLUSION

Despite the poor quality of available evidence and the great interstudy heterogeneity, combined procedures may be feasible with acceptable safety and satisfactory oncologic outcomes on individual basis.

Large incidental gastrointestinal stromal tumors in a patient presenting with acutely symptomatic nephrolithiasis: A case report

Gastrointestinal stromal tumors (GISTs) are rare mesenchymal neoplasms, representing approximately 1%-2% of all primary gastrointestinal malignancies. Incidental GISTs are often less than 1 cm when discovered and have been reported predominantly in obese patients undergoing surgery for other medical indications. We present the rare case of a large incidental GIST in a nonobese patient with acutely symptomatic nephrolithiasis. Large GISTs may be treated with neoadjuvant imatinib mesylate to reduce tumor size prior to surgery, though some tumors may experience little change in size despite effective treatment. Treatment response for GISTs can be monitored via imaging studies, such as computed tomography or magnetic resonance imaging, but computed tomography is generally preferred over magnetic resonance imaging.

Risk of second primary tumors in GIST survivors: A systematic review and meta-analysis

INTRODUCTION

Gastrointestinal stromal tumors (GISTs) are rare mesenchymal tumors arising in the gastrointestinal tract. Second primary tumors (SPTs) have been reported frequently, either synchronously or during follow-up, in patients diagnosed with GISTs.

METHODS

We carried out an electronic search of PubMed, SCOPUS, Web of Science, EMBASE, and the Cochrane Library seeking articles investigating the incidence of SPTs in patients with concomitant GIST. All studies were evaluated for heterogeneity before meta-analysis and for publication bias. Pooled incidence rate was estimated using fixed- and random-effects models. Subsite of SPTs was also investigated.

RESULTS

A total of 32 studies met the inclusion criteria, for a total of 19,627 patients with a diagnosis of GIST. The pooled prevalence of SPTs was 20%, with 14% and 3% being synchronous and metachronous tumors, respectively. We found a risk for several specific cancer sites, in particular gastrointestinal (5%) and genitourinary tract cancers (3%). The most frequently associated malignancies were: colorectal (17%), prostate (14%), gastric (9%), esophageal (5.5%), lung (5.4%), hepato-biliopancreatic (4.7%), breast (4.6%), lymphoma (4.4%), kidney (4.35%), and sarcomas (3.3%). Regression analyses revealed a significant positive association for all SPTs with follow-up and Miettinen risk.

CONCLUSIONS

Our results indicate that 20% of patients with GIST experienced a SPT, primarily synchronously with a diagnosis of GIST. In particular, we observed an excess of incident gastrointestinal tumors. These findings have important implications for both pathologists, who should perform extensive molecular analysis of surgical non-GIST specimens in resected patients, and for oncologists, who should continue to follow up GIST patients.

Coexistence of Primary GEJ Adenocarcinoma and Pedunculated Gastric Gastrointestinal Stromal Tumor

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors of the digestive system, although they account for only 0.1–3% of all gastrointestinal (GI) malignancies. They can arise anywhere along the GI tract with gastric predominance. Concurrent occurrence of GIST and gastroesophageal junction (GEJ) neoplasm is rare. We report a 55-year-old gentleman presenting with a polyp at the GEJ and a synchronous, large, and pedunculated gastric mass at the greater curvature. Those were treated with a wedge resection of the gastric pedunculated mass with negative margins along with transgastric submucosal resection of the GEJ polyp. Pathological examination confirmed synchronous invasive GEJ adenocarcinoma and a high-grade gastric GIST.

Clinical and pathological features of "small" GIST (≤2 cm). What is their prognostic value?

INTRODUCTION

Small GIST (<2 cm) are tumors whose biological behavior is benign and frequently involutes. Despite their increasing incidence, few studies have addressed the characteristics of these GIST. The aim of this work is to clarify the management of this entity.

PATIENTS AND METHOD

The characteristics of ≤2 cm GIST were initially described, and then compared with those >2 cm. This series comprises 104 patients and they were divided according to tumor size in 4 groups: tumors which are ≤2 cm (group 1, G1), >2 and ≤ 5 cm (G2), >5 and ≤ 10 cm (G3) and >10 cm (G4).

RESULTS AND DISCUSSION

Most of small GIST were asymptomatic and incidental, and were located in the stomach. There is an association between patients with associated tumors and asymptomatic GIST. A high overall mortality rate of up to 40% is observed being disease-specific mortality 4.5%. The disease-specific mortality increases proportionally with size. The overall survival (OS) at 5 years are lower for both <2 cm (61%) and >10 cm (53%) than the rest (85-91%). When analyzing the impact of tumor association on <2 cm GIST, we observed that the OS of patients with non-associated tumors was much higher than in the associated ones (90% vs 32% at 5 years, respectively), while no differences were observed in the disease specific survival.

CONCLUSIONS

Small GIST are tumors that are very often incidentally discovered in the course of complementary examinations. Its prognosis is very good, but it depends on the associated tumor.

Gastrointestinal stromal tumour and second tumours: A literature review

There are several tumours associated with gastrointestinal stromal tumour (GIST), most of them without an apparent family relationship; only 5% of them occur within the context of a family syndrome. In this article the corresponding literature about the former has been reviewed. A search in Pubmed was carried out, the methodology of which is described in detail in the body of the article. A total of 88 articles have been chosen for the review, next to the application of limits as well as a manual review. GIST patients have a twofold risk of developing a second tumour than the general population (4-33% of them develop a second neoplasm, either synchronic or metachronic). Most incident tumours associated with GIST are gastrointestinal and genitourinary tumours. In addition, patients with second tumours have a worse survival rate than those without second tumours.

[Additional primary malignancies in patients with gastrointestinal stromal tumors. Proposal for a new classification]

Additional primary malignancies in patients with gastrointestinal stromal tumor (GIST) is not only common but of growing interest in the scientific literature. This association is of great importance in terms of clinical challenge, diagnosis and therapy as well as for the prognosis impact it implies. In the published series there is a tendency to group these patients to determine the specific and distinguishable characteristics of GIST associated with other malignancies. On the other hand, there is no general consensus or unified classification. This classification would be of great interest, as it would unify criteria, agree groups to compare different series and demonstrate whether the aetiology underlying both tumours and the GIST's own characteristics really vary according to the type in question. We undertook a medical literature review and proposed a new classification for patients with GIST associated with other tumours.

Population-Based Epidemiology and Mortality of Small Malignant Gastrointestinal Stromal Tumors in the USA

BACKGROUND AND AIMS

Gastrointestinal stromal tumors (GISTs) have significant variability in size and malignant behavior. Our current understanding is limited to pathological analyses, autopsy studies, and small case series. The aim of the current study is to define the risk factors, incidence, and mortality rates of GIST <2 cm in the National Cancer Institute's Surveillance, Epidemiology, and End Results database.

METHODS

Patients with histologically confirmed malignant GIST <2 cm were studied from 2001 to 2011. GIST was defined by GI tumor site codes and GIST-specific histology codes.

RESULTS

We identified 378 patients with GIST <2 cm. The average age at diagnosis was 64.0 years with equal sex distribution. The most common tumor location was the stomach (62.2 %), followed by the small intestine (23.3 %), colon (5.6 %), and rectum (3.4 %). Most patients had localized disease (79.4 %), but 11.4 % had regional/distant metastatic disease. The annual incidence rate was 4.2 per 10,000,000 (10M). This was the highest among Blacks (7.6 per 10M). Among patients with GIST and no additional cancers, the 5-year GIST-specific mortality was 12.9 %. Moreover, there was a significantly increased 5-year GIST-specific mortality in those patients who had regionally advanced (34.0 %) or metastatic GIST (34.3 %), as compared to those patients with localized GIST (5.6 %).

CONCLUSIONS

This study represents the first population-based analysis of malignant GIST <2 cm. While quite rare, these tumors have an underappreciated disease-specific mortality. Further studies are needed to define the underlying reasons for the identified racial differences, to develop novel risk assessment schema for patients with these small tumors, and to determine appropriate indications for resection and/or medical therapy.

Synchronous gastrointestinal cancer and gastrointestinal stromal tumors: a single-institution experience

Background

A study was conducted to investigate the clinicopathological features and survival outcomes of gastrointestinal stromal tumors (GISTs) that are synchronous with other gastrointestinal cancers.

Methods

Clinical and pathological data of 286 patients with primary GIST from a single institution from January 2009 to December 2014 were reviewed.

Results

The entire study population comprised 286 patients with GISTs. Of these patients, 167 (58.4 %) were males and 119 (41.6 %) were females. The median age was 58 years old (in the range 29–86 years). A total of 47 patients were diagnosed with GISTs synchronous with other digestive tract malignancies (synchronous group), whereas 239 patients were diagnosed with non-synchronous disease (non-synchronous group). The concomitant digestive tumors in 27, 12, 7, and 1 patients were diagnosed as gastric carcinoma, esophageal carcinoma, colorectal carcinoma, and pancreatic adenocarcinoma, respectively. Compared with the synchronous group, the non-synchronous group exhibited a higher percentage of increased mitotic count (P = 0.011). The difference in tumor diameter between the two groups was statistically significant (P < 0.001). Patients in the non-synchronous group exhibited larger tumor size than the patients in the synchronous group (5.9 ± 3.5 cm vs. 1.6 ± 0.4 cm, P < 0.001). The majority of GIST lesions in the synchronous group were located in the stomach (P = 0.020). Lower risk stratifications and worse ECOG performance statuses were observed in the synchronous group (P < 0.001) than in the non-synchronous group. The 5-year overall survival rate was significantly higher in patients with no synchronous digestive tract malignancies than in patients with synchronous disease (70.8 vs. 34.1 %, P < 0.001).

Conclusions

Patients with GIST synchronous with other gastrointestinal cancers show worse prognosis than those with non-synchronous tumors. Clinicians should pay more attention to this subgroup.

Increased risk of additional cancers among patients with gastrointestinal stromal tumors: A population-based study

BACKGROUND

Most gastrointestinal stromal tumors (GISTs) are considered nonhereditary or sporadic. However, single-institution studies suggest that GIST patients develop additional malignancies at increased frequencies. It was hypothesized that greater insight could be gained into possible associations between GISTs and other malignancies with a national cancer database inquiry.

METHODS

Patients diagnosed with GISTs (2001-2011) in the Surveillance, Epidemiology, and End Results database were included. Standardized prevalence ratios (SPRs) and standardized incidence ratios (SIRs) were used to quantify cancer risks incurred by GIST patients before and after GIST diagnoses, respectively, in comparison with the general US population.

RESULTS

There were 6112 GIST patients, and 1047 (17.1%) had additional cancers. There were significant increases in overall cancer rates: 44% (SPR, 1.44) before the GIST diagnosis and 66% (SIR, 1.66) after the GIST diagnosis. Malignancies with significantly increased occurrence both before and after diagnoses included other sarcomas (SPR, 5.24; SIR, 4.02), neuroendocrine-carcinoid tumors (SPR, 3.56; SIR, 4.79), non-Hodgkin lymphoma (SPR, 1.69; SIR, 1.76), and colorectal adenocarcinoma (SPR, 1.51; SIR, 2.16). Esophageal adenocarcinoma (SPR, 12.0), bladder adenocarcinoma (SPR, 7.51), melanoma (SPR, 1.46), and prostate adenocarcinoma (SPR, 1.20) were significantly more common only before the GIST diagnosis. Ovarian carcinoma (SIR, 8.72), small intestine adenocarcinoma (SIR, 5.89), papillary thyroid cancer (SIR, 5.16), renal cell carcinoma (SIR, 4.46), hepatobiliary adenocarcinoma (SIR, 3.10), gastric adenocarcinoma (SIR, 2.70), pancreatic adenocarcinoma (SIR, 2.03), uterine adenocarcinoma (SIR, 1.96), non-small cell lung cancer (SIR, 1.74), and transitional cell carcinoma of the bladder (SIR, 1.65) were significantly more common only after the GIST diagnosis.

CONCLUSIONS

This is the first population-based study to characterize the associations and temporal relations between GISTs and other cancers by both site and histological type. These associations may carry important clinical implications for future cancer screening and treatment strategies.

Gastrointestinal stromal tumors in the setting of multiple tumor syndromes

PURPOSE OF REVIEW

Knowledge related to gastrointestinal stromal tumor (GIST) in the setting of nonhereditary and hereditary multiple tumor syndromes continues to expand. This review describes associations between sporadic GIST and second malignancies, as well as new contributions to our knowledge about hereditary GIST multiple tumor syndromes.

RECENT FINDINGS

Sporadic GIST patients have increased risk of developing synchronous/metachronous cancers, including nonhematologic and hematologic malignancies. Data suggest these associations are nonrandom, more prevalent in men and increase with age. New adrenal tumors have also been associated with nonhereditary Carney's triad. Meanwhile, understanding of the molecular basis of heritable GIST syndromes has improved. Several new familial GIST kindreds have been reported, including those with germline KIT and PDGFRα mutations. Knowledge about succinate dehydrogenase (SDH) deficiency and mutations in hereditary GIST syndromes has expanded. It is now known that neurofibromatosis-1-associated GISTs are SDHB-positive, whereas Carney-Stratakis syndrome-associated GISTs are SDHB-deficient with underlying germline mutations in SDH subunits A-D.

SUMMARY

Recognition and early diagnosis of GIST syndromes allows for improved comprehensive medical care. With additional understanding of the molecular pathogenesis of GIST multiple tumor syndromes, we can refine our screening programs and management of these patients and their families.

Rare cases reports of gastrointestinal stromal tumour (GIST)

The GISTs are rare tumours but even rarer is the localization in some districts. We reported two GISTs of the duodenum, two of the omentum and peritoneum, one of the rectum and one of a Meckel's diverticulum. These exceptional locations are confirmed by the relative difficult diagnosis, obtained in some cases only by the surgical treatment despite the CT and MR. The endoscopy is useful in hemorrhagic and duodenum forms, only for the diagnosis and for the control of blood loss. Surgical treatment in all cases was decisive without the need to make use of adjuvant therapy, with positive long-term results, which excluded the disappearance of relapses or secondary lesions.

Prognostic analysis of gastric gastrointestinal stromal tumor with synchronous gastric cancer

BACKGROUND

Many patients with gastric gastrointestinal stromal tumor (GIST) and synchronous gastric cancer have been described, most in single case studies. We retrospectively investigated the clinicopathologic features and prognostic effects of gastric GIST in patients with synchronous gastric cancer.

METHODS

The study enrolled 170 patients with gastric GIST, who had undergone complete surgical resection (R0) from January 2000 to December 2011. Forty-two patients had synchronous gastric cancer (CA Group), whereas 128 did not (Non-CA Group). The clinicopathologic features and potential prognostic factors in the two groups were compared.

RESULTS

Patients in the CA Group had more obvious symptoms, but a lower rate of preoperative diagnosis of gastric GIST (P <0.05). The two groups differed significantly in gender, age, greatest tumor diameter, risk stratification, tumor-associated ulcers, and CD117 and CD34 expression (P <0.05 each). Univariate analysis showed that age, risk stratification, postoperative oral imatinib and synchronous gastric cancer were predictive factors of survival (P <0.05). Cox regression analysis showed that risk stratification, postoperative oral imatinib and synchronous gastric cancer were independent predictors of survival (P <0.05). Stratified analysis showed that the 5-year overall survival rate was lower in patients with synchronous gastric cancer than in those without synchronous gastric cancer.

CONCLUSIONS

Gastric GIST with synchronous gastric cancer had a lower rate of preoperative diagnosis, with correct diagnosis often missed. Survival, however, depended primarily on the gastric cancer.