Coexistence of gastrointestinal stromal tumors with other neoplasms

Synchronous occurrence of gastric cancer and gastrointestinal stromal tumor: A case report and review of the literature

BACKGROUND

To evaluate the clinicopathological features and prognosis of gastric cancer (GC) occurring synchronously with gastrointestinal stromal tumor (GIST).

CASE SUMMARY

We report 19 patients with concurrent GC and GIST (17 male and 2 female, median age 62 years). GC was most often located in the lower third of the stomach. GIST was diagnosed preoperatively in four patients. GIST was most often located in the gastric body (n = 8, 42%). The most common growth pattern in GIST was extraluminal (n = 12, 63%). The positive expression rates of CD117 and CD34 in GIST were 100% and 95%, respectively. Most patients with GIST (n = 17, 89%) were very low or low risk. There was no recurrence of GIST during follow-up. The 3-year cumulative survival rate was 73.9%, and the 5-year cumulative survival rate was 59.2%. The combined analysis of this study and literature reports (47 reports, 157 patients) found that GC and GIST were usually located in the lower third (42%) and middle third (51%) of the stomach. GC was usually early (stage I: 42%), poorly differentiated (42%) intestinal-type adenocarcinoma (51%). GISTs were primarily small in diameter (median: 1.2 cm) and very low or low risk (89%).

CONCLUSION

Synchronous GC and GIST may not be rare. They have specific clinicopathological characteristics, and may have mutual inhibition in pathogenesis and progression.

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.

A Retrospective Study of Postoperative Outcomes in 98 Patients Diagnosed with Gastrointestinal Stromal Tumor (GIST) of the Upper, Middle, and Lower Gastrointestinal Tract Between 2009 and 2019 at a Single Center in Poland

BACKGROUND Gastrointestinal stromal tumors (GISTs) arise in the smooth muscle pacemaker interstitial cells of Cajal, or similar cells. The aim of this retrospective study between 2009 and 2019 from a single center in Poland was to assess the selected prognostic factors (location, tumor size, mitotic index, body mass index (BMI), length of hospital stay, age, sex, and coexistent neoplasm) and to investigate postoperative outcomes in 98 patients with GIST of the upper, middle, and lower gastrointestinal tract. MATERIAL AND METHODS Between 2009 and 2019, 98 patients (50 women and 48 men) with an average age of 63.8 years (range from 38 to 90 years) were operated on for GIST in the Department of Gastrointestinal Surgery in Katowice, Poland. Based on the intraoperative and postoperative investigations, the tumor size and mitotic index were determined in each case. RESULTS A statistically significant correlation between age and mitotic index (MI) was found (p=0.02). The higher the MI, the younger the age of the patients. However, regardless of sex, younger patients had a tendency to survive longer. A >60-year-old male patient's probability of survival was around 65% after 40 months. Higher mitotic index was also associated with larger tumor size (p<0.0001). Female patients had a tendency to survive longer than males. CONCLUSIONS The findings from this small retrospective study support the importance of preoperative evaluation and frequent postoperative follow-up for patients with GIST of the gastrointestinal tract, particularly in older male patients, and patients with malignant comorbidities, which are associated with increased mortality.

Coexistence of gastric cancer and gastric GIST with intra-tumor bleeding: successful embolization with subsequent total gastrectomy

Background

Gastrointestinal stromal tumor (GIST) is a rare tumor, however, simultaneous development of gastric cancer and gastric GIST has been documented more frequently in recent years. Rupture of gastric GIST is even more rare and occurred in 7% of all GISTs. Although ruptured GIST might be occasionally difficult to be managed by endoscopy, transcatheter arterial embolization (TAE) was reported to control bleeding from GIST effectively. We report herein a case of coexistence of gastric cancer and gastric GIST with progressing intra-tumor bleeding managed successfully by TAE and review the clinicopathological characteristics of this rare condition reported previously in the Japanese literature.

Case presentation

A 75-year-old woman with dyspnea and systemic edema was diagnosed as simultaneous occurrence of gastric cancer (histopathologically detected tubular adenocarcinoma pT2N1M0 fStageIIA) and gastric GIST (65 × 92 mm in diameter at the anterior wall of the fornix) with intra-tumor hemorrhage. Perceiving the progress of bleeding from tumor growth and exacerbating anemia, TAE of left gastric artery was performed. Then remission of anemia has been obtained, the patient underwent an elective radical surgery.

Conclusions

Simultaneous occurrence of gastric cancer and gastric GIST was speculated to be more common. TAE for ruptured GIST may be effective for hemostasis and reduction of tumor burden, which could facilitate minimal invasive surgery.

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.

Association Between Gastrointestinal Stromal Tumors and Other Malignancies: It Is Only a Matter of Time ? A Case Series and an Overview of Systematic Reviews

PURPOSE

Little is known about the sporadic coincidence of gastrointestinal stromal tumors (GISTs) with second primary tumors (SPTs). The aim of this study is to clarify if there is a clinicopathologic correlation responsible for the synchronous or metachronous occurrence of SPTs in GIST patients.

METHODS

We carried out a single-center, retrospective analysis on patients with GISTs surgically treated at our institution from January 2019 to June 2019. Two groups of patients were identified: isolated GIST (group A) and GIST associated with SPT (group B). A meta-review was conducted with the aim to examine the published systematic reviews that included studies assessing the SPT risk in GIST patients.

RESULTS

Thirty-nine patients were surgically treated for GIST during the study period, with seven (17.9%) of them having other SPTs. SPTs were most frequent in the colon. Group A patients had a lower mean age at initial diagnosis (56.8 ± 15.2 vs. 73.4 ± 16.6, P = 0.012). No statistically significant difference was found between the two groups in terms of tumor location, mitotic index, Ki-67 expression, risk classification, and imatinib therapy. The overview showed that the cumulative prevalence rate of SPTs ranged from 9.3 to 18.0%. SPTs were more frequent in the gastrointestinal tract (37.9-95.0%), followed by the genitourinary tract.

CONCLUSION

GIST patients under our care experienced a 17.9% overall risk of developing SPTs with different histology. When comparing patients with isolated GIST and patients with GIST and SPT, age was the only variable significantly related to the development of other neoplasms. However, the potential non-random association and causal relationship between GISTs and SPTs remain to be investigated.

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.

Gastrointestinal stromal tumors (GISTs) and synchronous intra-abdominal malignancies: case series of a single institution's experience

Background: Gastrointestinal stromal tumors (GISTs) quite often co-exist with other primary tumors, as seen in up to 33% of cases. In the literature such occurrences have primarily been described through case reports and rarely through case series, which is not sufficient to prove if there is an association between these two entities.

Materials and Methods: We conducted a retrospective study using medical and pathological records from sixty-nine patients who underwent surgical treatment for GIST in a single university surgical department between 2011 and 2019. Seven cases of GIST accompanying a synchronous primary tumor were identified and included in the study.

Results: Survival analysis comparing the overall survival of patients with single GIST versus patients with concurrent GIST and another primary tumor, has shown no statistically significant difference between these two groups (p = 0.19). However, when comparing the recurrence rate, patients with synchronous GISTs and another primary tumor have a statistically significant increased possibility for recurrence (p = 0.02). Statistical analysis comparing the size of GISTs between the two groups has shown that patients with single GIST have larger tumors than patients with synchronous tumors (p = 0.048).

Conclusions: The synchronous occurrence of GISTs and other intra-abdominal tumors is more common than previously considered, though it is not yet clear if there is a causal association for the concomitant occurrence. Further studies are required to elucidate the genetic and molecular mechanisms of carcinogenesis and progression associating GIST and synchronous tumors.

A case of synchronous association of a jejunal stromal tumor and a colic adenocarcinoma

Gastrointestinal stromal tumors are the most common mesenchymal tumors of the gastrointestinal tract. They are generally considered as solitary tumors. Here we report the case of a 66-year-old man with familial history of digestive cancers, admitted after a 2-months history of gastrointestinal bleeding. Colonoscopy showed a circumferential ulcerated tumor of the sigmoid which was a well differentiated adenocarcinoma on biopsy. Computerized tomography showed only the lesion of the sigmoid. The patient underwent a left colectomy followed by immediate end-to-end anastomosis. Per-operatively, jejunal mass was discovered and a jejunal segmentectomy was performed. Pathologic examination revealed a colic adenocarcinoma pT2N0M0 associated with a low risk stromal tumor of the jejunum CD117+ and DOG-1+. No adjuvant therapy was given. After 64 months of follow-up, the patient showed no evidence of recurrence. Clinicians should be aware of the coexistence of malignancies and carry careful investigations for accurate diagnosis and better patients' prognosis.

Frequency, localization, and types of gastrointestinal stromal tumor-associated neoplasia

BACKGROUND

In recent years, increasing evidence of second neoplasms associated with gastrointestinal stromal tumors (GIST) has been found. Numerous case reports, mostly retrospective studies and a few reviews, have been published. To our knowledge, however, no systematic review or meta-analysis of the existing data has been performed so far.

AIM

To prepare a compilation, as complete as possible, of all reported second tumor entities that have been described in association with GIST and to systematically analyze the published studies with regard to frequency, localization, and types of GIST-associated neoplasms.

METHODS

The MEDLINE and EBSCO databases were searched for a combination of the keywords GIST/secondary, synchronous, coincident/tumor, neoplasm, and relevant publications were selected by two independent authors.

RESULTS

Initially, 3042 publications were found. After deletion of duplicates, 1631 remained, and 130 papers were selected; 22 of these were original studies with a minimum of 20 patients, and 108 were case reports. In the 22 selected studies, comprising a total number of 12050 patients, an overall rate of GIST-associated neoplasias of 20% could be calculated. Most second neoplasias were found in the gastrointestinal tract (32%) and in the male and female urogenital tract (30%). The specific risk scores of GISTs associated with other tumors were significantly lower than those without associated neoplasias.

CONCLUSION

In this first systematic review, we could confirm previously reported findings of a more than coincidental association between GIST and other neoplasias. The question whether there is an underlying causal association will need further investigation. Our data suggest that even GIST with a very low risk of disease progression should prompt screening for second neoplasia and subsequent frequent controls or extended staging.

Malignant jejunal gastrointestinal stromal tumor with history of prostate cancer: A case report

RATIONALE

The problem of the coexistence of gastrointestinal stromal tumor (GIST) with other neoplasms is complex, and carcinomas of prostate is one of the common types of GIST-associated cancers. Doubling time of GIST is about 3.9 months for high-risk GIST, and the treatment paradigm for GIST has required the integration of surgery and molecular therapy.

PATIENT CONCERNS

A 70-year-old man with postoperative history of prostate cancer experienced fast-growing malignant jejunal GIST with multiple peritoneal metastases within 1 year.

DIAGNOSES

Enhanced computed tomography (CT) detected a neoplasm of small intestine with multiple peritoneal nodules and postoperative pathology confirmed GIST.

INTERVENTIONS

Oral imatinib after surgery, at 400 mg per day, was used for 4 years.

OUTCOMES

The patient remains well, and the peritoneal nodules located in front of the rectum disappeared gradually.

LESSONS

Physicians should be aware of possibility of GIST in patients with prostate cancer and can perform abdominal examination in these patients. For postoperative patients with prostate cancer, an yearly or half-yearly abdominal and pelvic cavity examination can be performed. Suspicion and timely work-up is necessary in these postoperative prostate cancer patients, especially when they have abdominopelvic pain.

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 Gastric Cancer and Multiple Small Gastrointestinal Stromal Tumors: Report of a Unique Case and Review of the Literature

Background

In recent years, the synchronous occurrence of tumors of different histotypes arising in the same organ has been reported more frequently in the literature. The simultaneous development of adenocarcinoma and gastrointestinal stromal tumor (GIST) has been documented rarely.

Summary

The coexistence of primary gastric adenocarcinoma and GIST has been detected incidentally on gastric mucosa, serosa or occasionally intramurally, at surgery, or gastroscopy for other reasons. We present a case of a 79-year-old male patient who underwent surgery for an advanced gastric carcinoma, where multiple nodules of GIST were incidentally discovered during the work-up of his gastrectomy specimen.

Key Message

GISTs range from small "low-risk" tumors to sarcomas. Small GISTs are found incidentally during unrelated surgery or autopsy. Multiple GISTs are extremely rare and usually associated with hereditary diseases.

Practical Implications

In any case of gastrointestinal neoplasm, the surgeon and pathologist should be alert to perform a thorough investigation. Our case could provide further awareness and insight into the entity of concurrent tumors.

Additional malignancies in patients with gastrointestinal stromal tumors (GIST): incidence, pathology and prognosis according to a time of occurrence-based classification

BACKGROUND

The aim of the study is to clarify if a classification based on the time of occurrence of associated malignancies in GIST patients can help in the understanding of the clinical controversies observed in these patients.

METHODS

We retrospectively reviewed all the patients diagnosed with GIST tumors between January 1999 and October 2016. They were divided into GIST patients associated with other tumors (A-GIST) and those not associated (NA-GIST). A-GIST patients were also divided into four types according to the proposed classification.

RESULTS

Of 104 GIST patients, 32 (30.7%) (A-GIST group) had at least one additional primary malignancy. The most frequent location of the associated malignancy was the GI tract (26%). Compared to NA-GIST, A-GIST were more often asymptomatic with a lower risk of recurrence. The main cause of death in NAGIST was GIST itself, being associated tumors the main cause of death in A-GIST group. No differences were found in DFS and OS between A-GIST and NA-GIST.

CONCLUSIONS

The use of the proposed classification classifies GIST patients with associated malignancies in different subtypes that differ substantially in terms of incidence, type of neoplasms associated, cause of the association and prognosis.

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.

Targeted ultra-deep sequencing unveils a lack of driver-gene mutations linking non-hereditary gastrointestinal stromal tumors and highly prevalent second primary malignancies: random or nonrandom, that is the question

The association of non-hereditary (sporadic) gastrointestinal stromal tumors (GISTs) and second primary malignancies is known to be nonrandom, although the underlying molecular mechanisms remain unknown. In this study, 136 of 749 (18.1%) patients with sporadic GISTs were found to have additional associated cancers, with gastrointestinal and genitourinary/gynecologic/breast cancers being the most prevalent. Gene mutations in GISTs and their associated colorectal cancers (CRCs) (n=9) were analyzed using a panel of 409 cancer-related genes, while a separate group of 40 sporadic CRCs not associated with GISTs served as controls. All 9 of the GISTs had either KIT (8 of 9) or PDGFRA (1 of 9) mutations that were not present in their associated CRCs. Conversely, all but one of the 9 GIST-associated CRCs exhibited an APC mutation, a TP53 mutation or both, while none of their corresponding GISTs harbored either APC or TP53 mutations. The genetic profile of CRCs with and without associated GISTs did not differ. Although population-based studies and case series worldwide, including ours, have unanimously indicated that the GIST-CRC association is nonrandom, our targeted ultra-deep sequencing unveiled a lack of driver-gene mutations linking sporadic GISTs to highly prevalent second primaries. Further studies are needed to elucidate other genetic alterations that may be responsible for this puzzling contradiction.

Uncommon Synchronous Association between Ovarian Carcinoma and Gastrointestinal Stromal Tumor: A Case Study and Literature Review

Background

The association of gastrointestinal stromal tumors (GIST) and other cancers is well known, but its synchronous occurrence with gynecological malignancies is very uncommon. Usually, the diagnosis is accidentally established. We describe a patient with GIST and concurrent ovarian cancer and discuss the clinical implications of this finding.

Case report

A 64-year-old woman with a prior diagnosis of ovarian cancer developed a second recurrence after having undergone two operations and adjuvant chemotherapy. While tumor debulking was performed, a small, nonsuspicious lesion was removed from the greater curvature of the stomach. Histology revealed a GIST.

Conclusion

The association of GIST and ovarian cancer is a rarity and its synchronicity may alter the oncological prognosis and therapy of the patient.

Association of Gastrointestinal Stromal Tumor and Acute Myeloid Leukemia Preceded by Myelodysplastic Syndrome with Refractory Anemia

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors of the gastrointestinal tract. GISTs are believed to be related to mutational activation of receptor tyrosine kinases, KIT, or platelet-derived growth factor receptor-alpha. The coexistence of GISTs with other neoplams has been extensively addressed in the literature. The most common second neoplasms are colorectal cancer, prostate cancer, and neoplasms derived from lymphoid tissue. In this case report, we describe a patient affected by GIST and acute myeloid leukemia preceded by myelodysplastic syndrome with refractory anemia. The clinicopathological characteristics of the patient are discussed and the literature is reviewed.

Clinicopathological and molecular characteristics of synchronous gastric adenocarcinoma and gastrointestinal stromal tumors

Synchronous gastric tumors that consist of both gastrointestinal stromal tumor (GIST) and adenocarcinoma are rare. We studied the clinicopathological and molecular characteristics of six cases containing both gastric adenocarcinoma and GIST. By means of immunohistochemical analysis, all GIST cells expressed CD117, CD34 and Dog1 in all six synchronous gastric adenocarcinomas with GIST, and in GIST alone. Sequencing analysis demonstrated that exon 11 c-kit mutations were present in two of six synchronous tumors and four of five GISTs. One of the two exon 11 c-kit mutations in synchronous adenocarcinomas with GISTs was an uncommon mutation of CTT > CCA at amino acid 576, and the other was a GTT deletion at amino acid 560. The mutation was a homozygous A > G mutation in exon 12 (amino acid 567) of PDGFR-α. We concluded that the exon 11 mutations were the most important in both cases of synchronous gastric adenocarcinoma with GIST and GIST alone. The mutation rate was higher in GIST alone than in synchronous adenocarcinoma with GIST.

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.

Efficacy of erlotinib and imatinib in a patient with a rectal gastrointestinal stromal tumor and synchronous pulmonary adenocarcinoma: A case report

The synchronous existence of lung cancer and gastrointestinal stromal tumors (GIST) is considered to be extremely rare. To the best of our knowledge, this is the first report about the treatment of lung cancer and GIST with two kinds of molecular targeting drugs. An 83-year-old woman with a rectal GIST, which carried a c-kit mutation, and pulmonary adenocarcinoma, which exhibited an epidermal growth factor receptor (EGFR) mutation, was treated alternately with imatinib and erlotinib. Good control over both diseases was achieved for two years. The present case is not only of interest due to the rare co-occurrence of GIST and lung cancer, but also because it involved two tumors carrying different gene mutations, and both tumors were brought under control using different molecular targeting drugs.

Clinicopathological features and prognosis of coexistence of gastric gastrointestinal stromal tumor and gastric cancer

The coexistence of gastric gastrointestinal stromal tumor (GIST) and gastric cancer is relatively high, and its prognosis is controversial due to the complex and variant kinds of presentation. Thus, the present study aimed to explore the clinicopathological features and prognostic factors of gastric GIST with synchronous gastric cancer.From May 2010 to November 2015, a total of 241 gastric GIST patients were retrospectively enrolled in the present study. The patients with coexistence of gastric GIST and gastric cancer were recorded. The clinicopathological features and prognoses of patients were analyzed.Among 241 patients, 24 patients had synchronous gastric cancer (synchronous group) and 217 patients did not (no-synchronous group). The synchronous group presented a higher percentage of elders (66.7% vs 39.6%, P = 0.001) and males (87.5% vs 48.4%, P < 0.001) than the no-synchronous group. The tumor diameter, mitotic index, and National Institutes of Health degree were also significantly different between the 2 groups (all P < 0.05). The 5-year disease-free survival and disease-specific survival rates of synchronous group were significantly lower than those of no-synchronous group (54.9% vs 93.5%, P < 0.001; 37.9% vs 89.9%, P < 0.001, respectively). However, the 5-year overall survival rates between synchronous and gastric cancer groups were comparable (37.9% vs 57.6%, P = 0.474).The coexistence of gastric GIST and gastric cancer was common in elder male patients. The synchronous GIST was common in low-risk category. The prognosis of gastric GIST with synchronous gastric cancer was worse than that of primary-single gastric GIST, but was comparable with primary-single gastric cancer.

Occurrence of Multiple Tumors in a Patient

An 81-year-old man initially presented with a right forearm mass that was found to be myxofibrosarcoma. In addition, he was found to have gastric and intragastric masses identified as neuroendocrine tumor (NET) and gastrointestinal stromal tumor (GIST; presenting synchronously), respectively, as well as a new left upper quadrant mass identified as desmoid tumor in the colon. The patient complained of melena, which was found to be due to metastatic myxofibrosarcoma in the transverse colon. Several reports have associated GIST with NET and some reports have associated GIST with sarcomas and NET with sarcomas; however, this is the first report to document all these tumors in a single patient. Several factors may have contributed to the development of these tumors, including growth factors secreted by NET, KIT mutation of GIST predisposing to additional tumors, immunosuppressed state, or an underlying genetic syndrome. This case highlights the importance of investigating for additional malignancies when a primary malignancy is discovered.

[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.

Synchronous occurrence of gastrointestinal stromal tumors and other digestive tract malignancies in the elderly

BACKGROUND/AIMS

Elderly patients with gastrointestinal stromal tumors (GISTs) synchronous with other digestive tract malignancies have been rarely reported. In this study, clinicopathological characteristics were evaluated among elderly patients with GISTs with or without coexisting digestive tract malignancies.

METHODS

A total of 161 patients (≥65 years) were retrospectively reviewed at the West China Hospital, Sichuan University from January 2009 to June 2014.

RESULTS

Sixty-one patients were diagnosed with synchronous digestive tract malignancies (synchronous group), whereas 100 patients were diagnosed with no synchronous condition (no-synchronous group). The synchronous group exhibited a higher percentage of males (70.49% vs. 53.00%, P = 0.028) and poorer Eastern Cooperative Oncology Group performance status than the no-synchronous group (P = 0.029). The three-year overall survival (OS) rate was significantly lower among patients with synchronous digestive tract malignancies than that among patients without synchronous condition (64.5% vs. 84.0%, P = 0.003). Multivariate analysis showed that the presence of synchronous digestive tract malignancies (P = 0.002), co-morbidity (P = 0.004), and mitotic count ≥10 mitoses/50 high power fields (P = 0.012) were associated with poor OS.

CONCLUSIONS

A synchronous condition with other digestive tract malignancies is common in elderly patients with GISTs. OS primarily depends on synchronous digestive tract malignancies, mitotic count, and co-morbidity.

Synchronous Appearance of Adenocarcinoma and Gastrointestinal Stromal Tumour (GIST) of the Stomach: A Case Report

Adenocarcinoma is the most common histological type of gastric tumour, accounting for approximately 95% of all gastric carcinomas. Gastrointestinal stromal tumours (GISTs) are rare mesenchymal neoplasms of the digestive tract. Synchronous adenocarcinoma and gastrointestinal stromal tumour (GIST) occurring in the stomach is rare and very few cases have been reported in literature. Synchronous tumours in the stomach are rarely diagnosed preoperatively. A 63-year-old gentleman was diagnosed with a gastric adenocarcinoma on endoscopic biopsy and underwent surgery. Postoperative histopathologic examination revealed 2 synchronous tumours with both adenocarcinoma and GIST. The adenocarcinoma was determined to be the aggressive tumour based on histologic features. GIST was categorized as a very low risk of malignancy, based on its size and mitosis. The patient underwent chemotherapy for adenocarcinoma. He is under follow up and is currently disease free. Careful histopathologic evaluation is required to detect co-existing rare synchronous tumours. Presence of the second tumour may require additional procedures or protocols.

Frequence, spectrum and prognostic impact of additional malignancies in patients with gastrointestinal stromal tumors

Currently available data on prognostic implication of additional neoplasms in GIST miss comprehensive information on patient outcome with regard to overall or disease specific and disease free survival. Registry data of GIST patients with and without additional neoplasm were compared in retrospective case series. We investigated a total of 836 patients from the multi-center Ulmer GIST registry. Additionally, a second cohort encompassing 143 consecutively recruited patients of a single oncology center were analyzed. The frequency of additional malignant neoplasms in GIST patients was 31.9% and 42.0% in both cohorts with a mean follow-up time of 54 and 65 months (median 48 and 60 months), respectively. The spectrum of additional neoplasms in both cohorts encompasses gastrointestinal tumors (43.5%), uro-genital and breast cancers (34.1%), hematological malignancies (7.3%), skin cancer (7.3%) and others. Additional neoplasms have had a significant impact on patient outcome. The five year overall survival in GIST with additional malignant neoplasms (n = 267) was 62.8% compared to 83.4% in patients without other tumors (n = 569) (P < .001, HR=0.397, 95% CI: 0.298-0.530). Five-year disease specific survival was not different between both groups (90.8% versus 90.9%). 34.2% of all deaths (n = 66 of n = 193) were GIST-related. The presented data suggest a close association between the duration of follow-up and the rate of additional malignancies in GIST patients. Moreover the data indicate a strong impact of additional malignant neoplasms in GIST on patient outcome. A comprehensive follow-up strategy of GIST patients appears to be warranted.

Metachronous Primary Adenocarcinoma of Lung During Adjuvant Imatinib Mesylate Therapy for Gastrointestinal Stromal Tumor of Stomach: A Case Report

Gastrointestinal stromal tumor (GIST) is the most common mesenchymal tumor in gastrointestinal tracts; however, the synchronous or metachronous coexistence of GIST with additional primary malignancy is not common.Here, we present an unusual case of gastric GIST with metachronous primary lung adenocarcinoma diagnosed during his adjuvant treatment with oral receptor tyrosine kinase inhibitor imatinib mesylate (400 mg daily). After 6-month use of imatinib, the patient suffered from dry cough and dyspnea. Subsequent lung biopsy demonstrated adenocarcinoma with diffuse interstitial changes.Our research emphasizes the possibility of an additional primary tumor with GIST, and reminds the clinicians to strengthen the surveillance of the additional cancer during the follow-up of GIST patients.

BRCA 1/2 gene mutation and gastrointestinal stromal tumours: a potential association

Mutations of the BRCA1/2 genes have been described in association with a number of malignancies including cancers of the breast, ovary, prostate and stomach, but have never been described in relation to gastrointestinal stromal tumours (GIST). We describe a patient with a BRCA2 8642del3insC mutation who developed prostate cancer, breast cancer and GIST. GIST has been shown to be associated with a number of malignancies, including some of the common BRCA1/2-related cancers, but it has never been associated with BRCA1/2 gene mutations. This report highlights the potential association between BRCA1/2 mutations and GIST, and aims to raise awareness for further genetic screening in GIST patients.

[C-KIT in gastrointestinal stromal tumors and associated malignancies: A Study in a population with genetic isolation]

INTRODUCTION

Gastrointestinal stromal tumors (GIST) are the most common mesenchymal tumors of the gastrointestinal tract. Numerous studies have reported the association between GIST and other neoplasms.

OBJECTIVES

The aim of this study was to investigate the possible association between GIST and other tumors in a genetically isolated population.

METHODS

A retrospective study was conducted of patients with GIST between 2002 and 2009 at our center. Epidemiological, pathological and family data in patients with GIST alone (group A) were compared with those in patients with GIST associated with other neoplasms (group B). A possible common genetic mechanism was investigated between GIST and associated malignancies by testing the detection of the immunohistochemical marker, CD117, in all tumors.

RESULTS

Twenty-two patients with GIST were identified, 10 in group A (45%) and 12 in group B (55%). In group B, the associated tumor was malignant in 6 patients (50%) and benign in another 6 (50%). Of the 22 patients with GIST, 8 (36%) had a family history of malignancies. Of these 8 patients, 7 (87.5%) were in group B (p=0.03) and 3 (37.5%) showed the same pathological type of neoplasm as their relatives. All GIST were positive for CD117 whereas associated malignancies were negative for this marker.

CONCLUSION

We did not find immunohistochemical positivity for CD117 in malignancies associated with GIST. Given the special characteristics of the study population, the association between GIST and associated malignancies may be incidental.

Coexistence of gastrointestinal stromal tumours (GIST) and malignant neoplasms of different origin: prognostic implications

BACKGROUND

Over the past decade, several changes occurred in diagnostics, treatment and understanding of pathogenesis of gastrointestinal stromal tumours (GIST). However, their coexistence with other malignancies of different histogenetic origin remains a challenging issue.

METHODS

Patients diagnosed with GIST in a 10-years period were identified retrospectively and clinical history and findings thoroughly explored for the presence of associated other malignancies. Follow up data were obtained and analysed for prognostic impact of the concurrent malignancy and/or GIST.

RESULTS

Thirty seven (27 males, 10 females) of 86 GIST-patients (43%) had another malignancy. Mean age was 70 years. Associated malignancies were gastrointestinal (n = 29; 69%), renal-/urological (n = 5; 12%), haematological (n = 4; 9.5%), cutaneous (n = 3; 7%) and thyroid (n = 1; 2.5%) in origin. Majority of GISTs occurred in stomach (65%) and small intestine (30.6%) and most (78%) were asymptomatic incidental findings during diagnostic or therapeutic procedures for associated malignancies. GIST size ranged from 0.1 cm to 9 cm (mean, 2.2 cm) and all of them had a low (<5/50 HPFs) or no mitotic activity. Thirty-one tumours (84%) were of no/very low/low risk and 6 were of intermediate risk. During follow-up (range 3-160 months, mean; 60 months), one patient suffered from distant metastases of GIST. Seven patients (19%) died of associated malignancies and three patients (8%) of other non-tumour-associated cause, but none died of GIST.

CONCLUSION

Coexistence of GIST with other malignancies is higher than previously reported and should draw attention of clinicians towards these incidental findings. Prognosis in these patients is usually determined by other malignancy and not significantly influenced by GIST. Therefore treatment algorithms should be focused on prognostically relevant malignancy.

Synchronous adenocarcinoma and gastrointestinal stromal tumors in the stomach

AIM: To review the clinicopathological characteristics of concurrent gastrointestinal stromal tumors (GISTs) and gastric adenocarcinoma.

METHODS: We retrospectively analyzed eight cases of synchronous adenocarcinoma and GIST in the stomach that had been surgically resected with curative intent between March 2003 and December 2008 in Xinhua hospital and Ruijin hospital. The adenocarcinoma was determined to be the primary tumor based on the histological features. The GIST cells were diffusely and strongly positive for CD34 and CD117.

RESULTS: The patients were six men and two women aged 47-80 years (average, 68.6 years). GIST was preoperatively detected in only one patient. The average sizes of the gastric adenocarcinomas and GISTs were 6.000 ± 2.6186 cm and 1.825 ± 1.4370 cm, respectively. All GISTs were very low- or low-risk lesions that were detected during evaluation, staging, operation or follow-up for gastric adenocarcinoma.

CONCLUSION: We hypothesized that the stomach was influenced by the same unknown carcinogen, resulting in a simultaneous proliferation of different cell lines (epithelial and stromal cell).

Concomitant jejunal sarcomatoid carcinoma and gastric GIST in patient with polymyalgia rheumatica: A case report

INTRODUCTION

Sarcomatoid carcinoma (SCA) of the small bowel is an extremely rare tumor with only 21 cases reported in literature and GISTs are relatively rare gastrointestinal neoplasms.

PRESENTATION OF CASE

We report a case of an 85 year-old female admitted with intestinal obstruction in June 2010. She suffered from polymyalgia rheumatica and was under surveillance for a presumed gastric GIST. A laparotomy was performed with resection of the jejunal obstruction and complete excision of the gastric mass. Histology confirmed a gastric GIST and sarcomatoid carcinoma of the small bowel. The patient was discharged 21 days after the operation and died on the 88th post-operative day.

DISCUSSION

Synchronous GISTs and other malignancies have been reported over the last years with increasing frequency. Sarcomatoid carcinoma of the small bowel is an aggressive neoplasm with poor survival rates and surgery is the cornerstones of treatment. Given its unpredictable clinical behaviour and concomitant association with other malignancies, GISTs require adequate surgical resection with careful, long-term follow-up.

CONCLUSION

This is the first case of concomitant gastric GIST with Sarcomatoid carcinoma of the small bowel, and the first report of sarcomatoid small bowel carcinoma in association with polymyalgia rheumatica.

Collision tumour involving a rectal gastrointestinal stromal tumour with invasion of the prostate and a prostatic adenocarcinoma

BACKGROUND

Gastrointestinal stromal tumours (GISTs) are the most common primary mesenchymal neoplasia in the gastrointestinal tract, although they represent only a small fraction of total gastrointestinal malignancies in adults (<2%). GISTs can be located at any level of the gastrointestinal tract; the stomach is the most common location (60-70%), in contrast to the rectum, which is most rare (4%). When a GIST invades into the adjacent prostate tissue, it can simulate prostate cancer. In this study, we report on a case comprising the unexpected collision between a rectal GIST tumour and a prostatic adenocarcinoma.

FINDINGS

We describe the complexity of the clinical, endoscopic and radiological diagnosis, of the differential diagnosis based on tumour biopsy, and of the role of neoadjuvant therapy using imatinib prior to surgical treatment.

CONCLUSIONS

Although isolated cases of coexisting GISTs and prostatic adenocarcinomas have previously been described, this is the first reported case in the medical literature of a collision tumour involving a rectal GIST and prostatic adenocarcinoma components.

VIRTUAL SLIDES

The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1238437468776331.

Adenosquamous carcinoma of the uncinate process of the pancreas with synchronous gastrointestinal stromal tumor of the stomach: Case report and review of the literature

Recently, the coexistence of gastrointestinal stromal tumors (GISTs) with other neoplasms has been studied with increasing frequency. Coexistence of pancreatic cancer with GISTs remains a rarity; however, here, we report a very rare case of adenosquamous carcinoma (ASC) of the uncinate process of the pancreas with synchronous GISTs of the stomach in a 62-year-old female. The patient presented with epigastric discomfort and vomiting. Radiographic imaging revealed two masses; one located at the body of the stomach and the other located at the uncinate process of the pancreas. Intraoperatively, a fine needle aspiration biopsy was conducted in the uncinate process of the pancreas, which revealed the malignancy of the masses. A pancreaticoduodenectomy and partial gastrectomy were then conducted, and subsequent pathological examinations identified an ASC of the pancreas and a GIST of the stomach. In our case, contrary to the majority of previous cases of synchronous GISTs and other malignancies, GIST was not an incidental finding. The initial suspicion on the GIST as the underlying cause of clinical symptoms led to the discovery of the ASC of the uncinate process of the pancreas.

Gastrointestinal stromal tumor

Gastrointestinal stromal tumor has received a lot of attention over the last 10 years due to its unique biologic behavior, clinicopathological features, molecular mechanisms, and treatment implications. GIST is the most common mesenchymal neoplasm in the gastrointestinal tract and has emerged from a poorly understood and treatment resistant neoplasm to a well-defined tumor entity since the discovery of particular molecular abnormalities, KIT and PDGFRA gene mutations. The understanding of GIST biology at the molecular level promised the development of novel treatment modalities. Diagnosis of GIST depends on the integrity of histology, immunohistochemistry and molecular analysis. The risk assessment of the tumor behavior relies heavily on pathological evaluation and significantly impacts clinical management. In this review, historic review, epidemiology, pathogenesis and genetics, diagnosis, role of molecular analysis, prognostic factor and treatment strategies have been discussed.

A nonrandom association of gastrointestinal stromal tumor (GIST) and desmoid tumor (deep fibromatosis): case series of 28 patients

BACKGROUND

Gastrointestinal stromal tumors (GISTs) and desmoid tumors (DTs) are two rare mesenchymal tumor. Anecdotal reports of individuals with both diseases led us to make the hypothesis that the association is a nonrandom event as the probability would be extremely low to observe such cases if they were independent events.

PATIENTS AND METHODS

We evaluated the existence of patients with GIST and DT in a large multicenter cohort at 10 institutions in the United States, Australia and Europe. Data on gender, age at diagnosis, KIT, PDGFRA, CTNNB1 mutation status and follow-up time after diagnosis were collected.

RESULTS

We identified 28 patients diagnosed with both tumors. DT was diagnosed after GIST in 75% of patients and concomitantly in 21%. In only one case (4%), GIST was diagnosed after DT. KIT or PDGFRA mutations were detected in 12 of 14 GIST, 9 in KIT exon 11, 2 in KIT exon 9 and 1 in PDGFRA.

CONCLUSION

A statistical analysis of these 28 cases suggests a nonrandom association between GIST and DT. Further studies may be able to elucidate the underlying biology responsible for this association.

Synchronous gastrointestinal stromal tumor and primary lung adenocarcinoma

Although rare, gastrointestinal stromal tumors (GIST) are the most common mesenchymal tumors of the gastrointestinal tract. The asynchronous occurrence of other malignancies in patients with GIST during the clinical course is relatively common. However, the synchronous coexistence of GIST and lung cancer has only rarely been reported. We experienced a case of coincidental primary lung adenocarcinoma and intestinal GIST. The present case is not only of interest due to the rare coincidence of GIST and lung cancer, but also because there was an epidermal growth factor receptor gene mutation in the lung cancer and a c-kit mutation in the GIST.

Prognostic factors for survival post surgery for patients with gastrointestinal stromal tumors

BACKGROUND

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal neoplasms located in the alimentary tract. Our aim was to assess the influence of prognostic factors on survival in patients surgically treated for GISTs.

STUDY

One hundred and five patients treated between January 1989 and December 2008 were available for study. A retrospective analysis of prognostic factors (age, gender, mitotic index, tumor location, tumor size, risk of malignant behavior, and coexisting other neoplasm) was performed. Univariate and multivariate survival analyses were undertaken.

RESULTS

Univariate analyses revealed the importance of patient gender (p = 0.007), disease location (p = 0.055), mitotic index (p = 0.054) and coexistence with other neoplasms (p = 0.004). However, multivariate analysis showed 3 independently statistically significant factors: coexistence with other neoplasm (RR = 3.53, p = 0.004), male gender (RR = 2.60, p = 0.011) and mitotic index ≥10/50 HPF, (RR = 2.60, p = 0.042).

CONCLUSIONS

Our study has shown that male gender, a high mitotic index ≥10/50 HPF, and coexistence with other malignant neoplasms were independent poor prognostic factors in patients with GIST. The presence of middle or lower gut disease location leads to an increased risk of mortality when compared with the upper gut.

Synchronous tumors: adenosquamous carcinoma of pancreas and GIST of stomach

We report herein a unique case of an adenosquamous carcinoma (ASC) of the pancreas and a synchronous gastrointestinal stromal tumor (GIST) of stomach in a 75-year-old Caucasian male. He presented with painless jaundice and generalized pruritus and was found to have a pancreatic head mass. Whipple's procedure was performed and yielded the above diagnoses. Ductal pancreatic adenocarcinoma, not a much rarer and more aggressive ASC subtype, has previously been shown to co-exist with GIST in some surgical series. In addition, the incidentally discovered GIST in our patient involved the stomach and not the small intestine, which is the predominant GIST location when concurrently diagnosed with other GI tumors. At the time of this publication, our patient, who received adjuvant chemoradiotherapy, remains disease-free 14 months after the abdominal surgery.

Exon 11 mutations, Ki67, and p16(INK4A) as predictors of prognosis in patients with GIST

Prognostic biomarkers for GIST are under investigation. The aim of this study was to assess whether exon 11 mutations, Ki67, and p16(INK4A) are predictors of prognosis in GIST. Consecutive GIST cases (n=84) had their specimens evaluated for exon 11 mutations and expression of Ki67 and p16(INK4A). Surgical cases were categorized according to NIH and Miettinen's classification, and survival was analyzed from hospital database. GISTs were predominately gastric (45%) and with spindle cell morphology (74%). The risk category was very low or low in 28%, intermediate in 23%, and high in 49%. Exon 11 mutation was identified in 29 (48%) out of 60 cases studied. There were 12 point mutations, 10 deletions, 4 duplications, and 3 double mutations. A third of GISTs had either high Ki67 index (>3%) or negativity for p16(INK4A). In multivariate analysis, independent predictors of mortality were Ki67>3% (HR=7.3; P=0.036) and high mitotic index (HR=10.4; P=0.043). There was no association between exon 11 mutations and survival. This study suggests that Ki67>3% is an independent predictor of poor prognosis in patients with GIST. Exon 11 mutations and negativity for p16(INK4A) need further studies to address the prognostic value.

Coexistence of primary gastric giant cell-rich leiomyosarcoma and gastrointestinal stromal tumor: report of a very rare combination and review of the literature

Leiomyosarcoma is one of the most common types of soft tissue sarcoma, usually seen in deep soft tissues of the extremities and retroperitoneum. Leiomyosarcoma primarily involving the gastrointestinal tract is uncommon. This report presents a rare case of primary gastric giant cell-rich leiomyosarcoma associated with a gastrointestinal stromal tumor of the stomach in a 51-year-old man. The patient was alive with no evidence of recurrence 10 months later. To the authors' knowledge, this association has not been previously reported.

Frequency, phenotype, and genotype of minute gastrointestinal stromal tumors in the stomach: an autopsy study

Gastrointestinal stromal tumors are the most common mesenchymal tumors of the human digestive tract. Up to 85% of these tumors show somatic gain-of-function mutation of the receptor tyrosine kinase c-KIT gene. A recent study has shown a high frequency (22.5%) of minute gastrointestinal stromal tumors in stomachs examined during routine autopsies. The aims of our study were to confirm the previously reported incidence of gastric gastrointestinal stromal tumors in routine autopsies and to investigate their molecular alterations. Gastrointestinal stromal tumors were collected prospectively from 578 autopsies over an 18-month period. After recording the size and location of each lesion, representative tissue samples were processed for hematoxylin and eosin staining and immunohistochemically stained for CD117 and CD34. Microdissected DNA from all identified gastrointestinal stromal tumors was studied for c-KIT and platelet-derived growth factor receptor α mutations. We identified 17 gastrointestinal stromal tumors in 578 consecutive autopsies (2.9%) located in the gastric body (47%) and fundus (47%). One tumor location was not recorded. All tumors were immunohistochemically positive for CD117 and CD34. DNA analysis showed c-KIT mutations in 11 cases. One platelet-derived growth factor receptor α mutation was found. The incidence of gastric minute gastrointestinal stromal tumors (2.9%) is higher than the reported clinical incidence. All are benign tumors, and most, including minute tumors, contain c-KIT mutations. This finding highlights the fact that c-KIT mutations are an early event in the evolution of gastrointestinal stromal tumors but are not sufficient per se for clinically relevant disease.

Synchronous well differentiated neuroendocrine tumour and gastrointestinal stromal tumour of the stomach: a case report

BACKGROUND

Well differentiated neuroendocrine tumours (carcinoids), arising from cells of the diffuse neuroendocrine system, represent the most commonly encountered gastric endocrine tumours. Gastrointestinal stromal tumours (GISTs), which stem from interstitial Cajal cells located within the wall of the gastrointestinal tract and have a characteristic immunoreactivity for CD117 (c-kit protein), account for the majority of gastrointestinal mesenchymal neoplasms. Simultaneous occurrence of a GIST with a well differentiated neuroendocrine tumour in the stomach is very rare.

METHODS

Clinical history, endoscopy and histopathological findings were utilized for our diagnostic considerations.

RESULTS

We report the coexistence of a high risk GIST with a well differentiated neuroendocrine tumour of benign clinical behavior, both located in the stomach, in a 62-year-old man previously operated for a gastric well differentiated neuroendocrine tumour with uncertain malignant behaviour.

CONCLUSIONS

Even single well differentiated, sporadic, NETs of small size may coexist with GISTs. An appropriate initial therapeutic approach combined with a scrupulous follow-up seems to play a significant role in terms of preventing a metastatic disease.