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Cyril Fisher

Publications and source records attributed to Cyril Fisher.

At least 37 records · Page 2Linked to original sources
PubMed2004

Small bowel gastrointestinal stromal tumours and ampullary cancer in Type 1 neurofibromatosis.

BACKGROUND: Type 1 neurofibromatosis (NF-1) is an autosomal dominant disorder with variable penetrance; approximately 50% of cases present as new mutations CASE REPORT: We report a case of a 56 year-old man with Von Recklinghausen's disease, carcinoma of the ampulla of Vater and incidental benign gastrointestinal stromal tumours of the jejunum. CONCLUSIONS: Coexistence between ampullary carcinoid, ectopic pancreatic tissue in the jejunum and neurofibroma of the jejunum in NF-1 has been previously described however; the association of synchronous carcinoma of the ampulla of Vater and gastrointestinal stromal tumour of the jejunum in NF-1 has not been previously reported.

Journal Article↗
PubMed2004

Changing concepts in the pathological basis of soft tissue and bone sarcoma treatment.

Though soft tissue sarcomas are rare considerable progress has been made in the clinical and biological understanding of these neoplasms. This has led to the launch of a new WHO classification of soft tissue tumours in 2002, which integrate morphological data with tumour specific (cyto-) genetics. Moreover worldwide consensus has grown how to predict clinical behaviour based on a specific grading system and which specific types of tumours seem not to obey these rules. As a consequence entry criteria for multi-institute prospective trials have changed over the last few years. The recent identification of tumour specific drug targets by immunohistochemistry has had impact on specimen requirements and handling as well as laboratory standards. These changes in concepts, classification, and processing of soft tissue sarcomas have had impact on patient selection and treatment and formats of multi-institute trials.

Biomarkers, Tumor↗
PubMed2004

Aberrant expression of tight junction-related proteins ZO-1, claudin-1 and occludin in synovial sarcoma: an immunohistochemical study with ultrastructural correlation.

Synovial sarcoma demonstrates epithelial differentiation, either by light microscopy (biphasic synovial sarcoma) or by immunohistochemical/ultrastructural methods only (monophasic) and poorly differentiated synovial sarcoma. Although the glands of synovial sarcoma are known to have tight junction-like structures, far less is known about junction formation in the spindled component of synovial sarcomas. Additionally, it is unknown whether the tight junctions of synovial sarcoma are normally constituted. The tight junction is a multiprotein complex consisting of numerous proteins that include ZO-1, claudin-1 and occludin. A total of 35 cases of synovial sarcoma (13 biphasic, 14 monophasic and eight poorly differentiated) were immunostained for ZO-1, claudin-1 and occludin using commercially available antibodies, heat-induced epitope retrieval and standard avidin-biotin technique. When available, corresponding electron micrographs were reviewed. For five cases, the presence of either an SYT-SSX1 (three cases) or SYT-SSX2 (two cases) gene fusion was known. Positive cases showed particulate membrane staining. The glands of biphasic synovial sarcomas expressed ZO-1 (13/13), claudin-1 (12/13) and occludin (11/13) in a manner identical to normal glandular epithelia, at the apical portion of the lateral membrane. The spindle cells of biphasic synovial sarcomas showed abnormal circumferential membranous expression of ZO-1 (12/13), claudin-1 (6/13) and occludin (3/13). Monophasic synovial sarcomas expressed ZO-1 in a circumferential pattern (13/14) but less often claudin-1 (4/14) or occludin (3/14). Poorly differentiated synovial sarcomas expressed ZO-1 (8/8) and claudin-1 (6/8) but only rarely occludin (2/8). By electron microscopy, recognizable tight junctions were seen only in glands. No correlation was seen between histologic subtype or fusion type and expression of tight junction proteins. We conclude that the glands of biphasic synovial sarcomas show well-organized, true epithelial tight junctions. In contrast, the spindled cells of all synovial sarcomas show significant abnormalities in the expression and localization of tight junction proteins, suggesting partial and/or aberrant epithelial differentiation.

Claudin-1↗
PubMed2004

Minichromosome maintenance protein in myxofibrosarcoma.

Histopathological assessment of myxofibrosarcoma may be difficult, especially on the basis of a small core biopsy, which enables only a crude evaluation of grade and prognosis. We have tested the hypothesis that determination of cell cycle state may assist in the diagnostic assessment of myxofibrosarcoma. We have studied 51 cases of high-grade (n=20), intermediate-grade (n=21), and low-grade (n=10) myxofibrosarcomas, as well as nine cases of benign myxoma. Cell cycle state within tumors was determined by immunostaining for the recently described marker minichromosome maintenance protein 2 (MCM2), together with Ki67. Labelling indices for both markers were correlated with tumor grade, mitotic index, and time to first recurrence. The MCM2 labelling indices were significantly higher than the Ki-67 labelling indices. Both indices showed a significant correlation with the mitotic index and both showed significant increases with increasing grade of myxofibrosarcoma. The MCM2 labelling index (but not the Ki67 labelling index) showed a significant inverse exponential correlation with the time to first recurrence. Myxoid and cellular areas showed no difference in the MCM2 and Ki-67 labeling index, suggesting that clinically useful information could be obtained from any component of a myxofibrosarcoma sampled in a needle biopsy and/or cytological specimen. We therefore suggest that assessment of cell cycle state may be a useful diagnostic adjunct in the histopathological assessment of myxofibrosarcoma, by enabling more accurate determination of grade and prediction of outcome.

Adult↗
PubMed2004

Anaplastic lymphoma kinase (ALK 1) staining and molecular analysis in inflammatory myofibroblastic tumours of the bladder: a preliminary clinicopathological study of nine cases and review of the literature.

Inflammatory myofibroblastic tumours (IMFT) may arise at any anatomical site, including lung, soft tissues, retroperitoneum and bladder. Although morphologically similar, these lesions encompass a spectrum of entities with differing aetiology, ranging from reactive/regenerative proliferations to low-grade neoplasms with a risk of local recurrence, but no significant metastatic potential. Vesical IMFT usually presents as a polypoid mass with a pale firm cut surface and can be of considerable size, mimicking a malignant tumour clinically and radiologically. Its good outcome, however, warrants conservative surgical excision, emphasising the importance of identification and distinction from malignant tumours of the bladder that may require more radical surgery and/or adjuvant therapy. We conducted a preliminary retrospective, comparative immunocytochemical study of 20 bladder tumours, including nine IMFTs, five spindle cell (sarcomatoid) carcinomas, two rhabdomyosarcomas, two leiomyosarcomas and two neurofibromas. The results confirmed IMFT positivity for smooth muscle actin, desmin and cytokeratin in 78-89% cases, resulting in potential confusion with sarcomatoid carcinoma or leiomyosarcoma. In contrast, cytoplasmic anaplastic lymphoma kinase (ALK 1) staining was present in eight IMFT (89%), but was not seen in any other lesion examined. The ALK 1 staining was confirmed by fluorescence in situ hybridisation, with translocation of the ALK gene present in 15-60% tumour cells in four of six IMFT examined, but not in four cases of sarcomatoid carcinoma or three of leiomyosarcoma. In conclusion, ALK 1 staining may be of value in the distinction of vesical IMFT from morphologically similar entities, and often reflects ALK gene translocations in these lesions.

Actins↗
PubMed2004

CD44 loss in gastric stromal tumors as a prognostic marker.

BACKGROUND: The adhesion molecule CD44 (CD44s; CD44H) and its isoforms (CD44v3-6 and v9) are preferentially expressed by different cell types. These transmembrane glycoproteins are involved in cell-cell and cell-matrix interactions and in cell trafficking and, thus, may play a role in tumor metastasis and/or local invasion. The expression pattern of CD44s and variant isoforms, particularly CD44v6 and CD44v9, of some neoplasms, including soft tissue tumors, correlates with clinical course and outcome. The clinical behavior of gastrointestinal stromal tumors (GIST) is site specific; however, other reliable predictors of clinical outcome have not been identified. Thus, the prognostic value of CD44s and isoform expression in GIST were evaluated by immunohistochemistry of tissue microarrays. DESIGN: Paraffin-embedded formalin-fixed tissue cores (129: 103 GIST and 26 normal stomach smooth muscle) from 33 patients with clinical outcome data were collected and used for the construction of the tissue microarrays. One to five tissue cores from each patient specimen were evaluated (mean = 3 tissue cores/patient). Array slides were stained with anti-CD44s (CD44H) and with antibodies to v3, v4, v5, v6, and v9 isomers. CD44s and isoform expression and staining intensity were scored semiquantitatively without knowledge of patient identity or outcome: 0 = no; 1 = weak; 2 = moderate; 3 = moderate to strong; 4 = strong. The scores of multiple cores from the same GIST were averaged; the nonneoplastic smooth muscle was similarly graded. CD44s and isoform expression and intensity were compared with outcome. RESULTS: The 33 patients with gastric GIST, 0.8 to 30 cm in size, were followed for 1 to 111 months with a median follow-up of 7 months (mean 17.5 months). The overall median survival was 25 months. Nine of the 33 (27%) patients had metastases, 9 (27%) had recurrent disease, and 9 (27%) died of disease (9-111 months; mean 39 months; median 23 months). All 18 patients with GIST CD44s expression > 2+ were alive at last follow-up (1-62 months; median 3.5 months; mean 11 months). More than half (53%) of patients with GIST CD44s expression < or = 2+ died (9-111 months; median 23 months; mean 38 months); the median follow-up of the surviving patients with CD44 expression < or = 2 was 5 months (2-22 months; mean 6.5 months; log rank P = 0.07). The majority of tumors were variably positive CD44v3 and CD44v4, but there was minimal staining (number of cases and/or expression level) with antibodies directed against the v5, v6, and v9 isomers. CONCLUSION: These preliminary results suggest that although gastric GISTs variably express CD44s and variants, only the expression of CD44s correlates with clinical outcome with loss of CD44s positivity correlating with poor clinical outcome.

Adult↗
PubMed2004

Leiomyosarcoma of the kidney: a clinicopathologic study.

Leiomyosarcoma of kidney is a rare lesion for which limited data are available. Cases coded as leiomyosarcoma of the kidney from three institutions were reviewed. These cases comprised 3 men and 7 women, 40 to 75 years of age. Immunohistochemistry was performed where possible and clinical follow-up information was obtained. On immunohistochemical staining, 6 of 6 tumors expressed smooth muscle actin, desmin, calponin, and h-caldesmon, and epithelial membrane antigen was positive in 1 of 5. Tumors were negative for cytokeratin and S-100 protein. Follow-up information was available for 9 patients. Two patients had metastases at diagnosis, four developed metastases, and two had recurrent disease. Five of 9 died of disease. Two patients were alive with no evidence of disease after 19 and 60 months, and 2 patients were alive with disease after 48 months and 56 months. Comparing outcome with tumor grade, the one patient with grade 1 tumor was alive with no evidence of disease; of 5 patients with grade 2 tumor, 2 died of disease, 1 was alive with no evidence of disease, 1 was alive with disease, and 1 was alive with extensive disease; all 3 grade 3 patients died of disease. In summary, the majority of renal leiomyosarcomas are intermediate or high grade with correspondingly poor prognosis.

Adult↗
PubMed2004

Malignant perivascular epithelioid cell tumour ("PEComa") of soft tissue: a unique case.

Tumours of perivascular epithelioid cells (PEComas) are being increasingly reported at visceral and somatic sites. Both benign and malignant variants have been identified, although clinical follow-up is often limited, which prevents meaningful predictions of behavior. We report the case of a malignant soft tissue PEComa with histologically confirmed regional lymph node metastases and radiologically confirmed pulmonary metastases. The light microscopic appearance and immunohistochemical profile (HMB-45, smooth muscle actin positive) and electron microscopic appearance support perivascular epithelioid cell differentiation.

Aged↗
PubMed2004

Myofibroblastic malignancies.

Malignant tumors composed of myofibroblasts are increasingly being recognized, but their existence remains controversial. Currently accepted examples within this category represent spindle cell or pleomorphic neoplasms of the soft tissues with a spectrum of histological grades. Low- and intermediate-grade myofibrosarcomas are fascicular spindle cell neoplasms resembling fibrosarcoma or leiomyosarcoma. They infiltrate deep soft tissue with disproportionate involvement of head and neck sites and can recur locally but infrequently metastasize. They variably express myoid immunohistochemical markers, and their differential diagnosis includes benign myofibroblastic proliferations such as fasciitis and fibromatosis as well as other types of spindle cell sarcoma. High-grade (pleomorphic) myofibrosarcomas are an ultrastructurally defined subset of malignant fibrous histiocytoma, which they resemble in morphology and behavior. Inflammatory myofibroblastic tumor and infantile fibrosarcoma are neoplasms that have myofibroblastic features and have been included in this category, but they have distinctive genetic findings. This article reviews the concept of myofibrosarcoma and describes its variants.

Adolescent↗
PubMed2003

Can patients with relapsed, previously untreated, stage I epithelial ovarian cancer be successfully treated with salvage therapy?

PURPOSE: The role of adjuvant chemotherapy in early-stage epithelial ovarian cancer (EOC) has been controversial. We have previously reported the cases of patients managed with a policy of observation only. We now present the salvage rate for the patients in that study who experienced relapse. PATIENTS AND METHODS: One hundred ninety-four patients with stage I EOC presenting between 1980 and 1994 received no adjuvant chemotherapy, but were treated with platinum-based chemotherapy at relapse. We calculated the progression-free survival (PFS) and overall survival (OS) for the whole cohort and the salvage rate for those who experienced relapse. We defined salvage as freedom from relapse for 5 years after platinum treatment. RESULTS: Sixty-one (31%) of 194 patients experienced relapse, and 55 received platinum-based chemotherapy. Twenty-four percent were progression-free at 5 years after this treatment. Clear-cell histology and cyst rupture before the patients' original surgery were independent prognostic factors for PFS after salvage chemotherapy. The OS for all 194 patients is 72% at 10 years (median follow-up, 8.7 years), with an 80% disease-specific survival (DSS). CONCLUSION: We have shown that some patients with stage I EOC can be successfully treated with a salvage chemotherapy regimen after a policy of observation only. Interestingly, approximately 30% of stage I patients who die within 10 years do so from causes other than EOC (OS, 72%; DSS, 80%). Our findings need to be taken into consideration when the results from recent randomized trials of adjuvant chemotherapy in this patient population (International Collaborative Ovarian Neoplasm Trial 1/European Organization for Research and Treatment of Cancer Adjuvant Chemotherapy in Ovarian Neoplasm Trial) are being discussed with patients.

Adult↗
PubMed2003

Chromosomal imbalances in pleomorphic rhabdomyosarcomas and identification of the alveolar rhabdomyosarcoma-associated PAX3-FOXO1A fusion gene in one case.

Rhabdomyosarcomas (RMS) are soft tissue sarcomas resembling developing skeletal muscle, and pleomorphic rhabdomyosarcomas (PRMS) are a rare nonpediatric entity. Little molecular cytogenetic information exists for PRMS, and their relationship to other subtypes of rhabdomyosarcoma and other sarcomas is unclear. Chromosomal imbalances were determined in seven well-characterized cases of PRMS using comparative genomic hybridization. The smallest overlapping regions of gain were 1p22 approximately p33 (71%), 7p (43%), 18/18q (43%), and 20/20p (43%), and the regions of loss were 10q23 (71%), 15q21 approximately q22 (57%), 3p, 5q32 approximately qter, and 13 (all 43%). Four of the seven cases had amplicons involving the regions 1p21 approximately p31, 1q21 approximately q25, 3p12, 3q26 approximately qtel, 4q28 approximately q31, 8q21 approximately q23/8q, and 22q. These regions are distinct from those frequently associated with the alveolar subtype, whereas the embryonal subtype without anaplasia is rarely associated with amplification events other than gain/amplification of 8q material. The regions of imbalance appeared more similar to those reported for malignant fibrous histiocytomas (MFH) and osteosarcomas, consistent with the suggestion that PRMS can be considered part of the spectrum of MFH. In addition, one of the cases classified as PRMS showed evidence for the presence of a PAX3-FOXO1A fusion gene, which is characteristic of the alveolar subtype of RMS.

Aged↗
PubMed2003

Epithelioid sarcoma: an immunohistochemical analysis evaluating the utility of cytokeratin 5/6 in distinguishing superficial epithelioid sarcoma from spindled squamous cell carcinoma.

BACKGROUND: Epithelioid sarcoma (ES) is a rare, aggressive soft tissue tumor characterized by nodular aggregates of epithelioid and/or spindled cells that are immunoreactive to cytokeratins (CKs) and epithelial membrane antigen. ES that arises in the dermis may cause epidermal ulceration and can resemble, clinically, morphologically and immunohistochemically, cutaneous squamous cell carcinoma. CK 5/6 has recently been found to be an excellent marker of squamous cell carcinoma, including spindled variants, but it is not known if this marker can be utilized to distinguish superficial ES from cutaneous spindled squamous cell carcinoma (SSCC). METHODS: Twenty-four cases of ES with typical histologic features and 10 cases of SSCC with ultrastructural evidence of epithelial differentiation were studied. Immunohistochemical analysis using an antibody to CK 5/6 was performed. The extent of immunoreactivity was evaluated in a semiquantitative manner using the following scale: 0, < 5% of cells staining; 1+, 6-25% of cells staining; 2+, 26-50% of cells staining; 3+, 51-75% of cells staining; 4+, > 75% of cells staining. RESULTS: CK 5/6 was expressed in all 10 cases of SSCC, including one case with 3+ staining and six cases with 4+ staining. In contrast, CK 5/6 staining was found only in rare tumor cells (1+ staining) in one of 24 (4%) cases of ES. CONCLUSIONS: CK 5/6 staining is useful in distinguishing superficial ES from cutaneous SSCC.

Biomarkers, Tumor↗
PubMed2003

Paratesticular liposarcoma: a clinicopathologic study.

Paratesticular liposarcomas are rare and typically reported as isolated cases or as components of larger studies of liposarcomas. We studied a series of these tumors. All cases of paratesticular liposarcomas were retrieved from the archives of the Royal Marsden Hospital and the Johns Hopkins Hospital. Slides were reviewed and clinical information obtained. There were 30 paratesticular liposarcomas from men aged 41-87 years (mean 63 years; median 65 years) that involved the spermatic cord (23, 76%), testicular tunics (6, 20%), and epididymis (1, 4%). Tumors ranged from 3 to 30 cm (mean 11.7 cm; median 10 cm). Nineteen were well-differentiated liposarcomas (WDLs) and 10 were dedifferentiated liposarcomas (DDLs, five with high-grade and five with low-grade dedifferentiation). One was a myxoid/round cell liposarcoma with 70% round cell areas. All patients were treated by radical orchiectomy. One patient with WDL received radiation after his second recurrence and the myxoid/round cell liposarcoma received radiation and chemotherapy. Follow-up information was available for 16 of the patients, including 10 WDLs (range 24-216 months, mean 106 months), 5 DDLs (14-30 months, median 24 months), and for the myxoid/round cell liposarcoma (14 months) (range for all cases 14 months to 22 years; mean 87 months, median 36 months). Six of the WDLs (60%) recurred at 2, 4, 6, 10, 18, and 21 years (median 8 years). The lesion that recurred at 18 years (case no. 6) displayed foci of high-grade dedifferentiation in the recurrence, although the patient was disease free at 19 years. One patient with WDL had two recurrences at 4 and 7 years, and another had six recurrences over a 17-year period. Only one example of DDL recurred, at 30 months; another patient, who refused therapy for 15 years, had a primary tumor 30 cm in diameter, displayed pulmonary metastases 1 month after excision, and died after 14 months. The patient with MRCL had abdominal metastases after 1 year and was alive at 14 months. In summary, paratesticular WDL had a prolonged course with recurrences in more than half the cases, sometimes late. There were no metastases and the overall prognosis was good. One DDL recurred and only one of five (20%) developed metastases, but the mean follow-up for DDL was only 24 months.

Adult↗
PubMed2003

Low-grade fibromyxoid sarcoma and hyalinizing spindle cell tumor with giant rosettes share a common t(7;16)(q34;p11) translocation.

Low-grade fibromyxoid sarcoma (LGFMS) is a rare metastasizing soft tissue tumor with deceptively bland histologic features. The hyalinizing spindle cell tumor with giant rosettes (HSCT) is thought to be a closely related tumor differing only by the presence of collagen rosettes. We report the occurrence of a common t(7;16)(q34;p11) translocation in 2 cases of HSCT and 2 cases of LGFMS, thereby providing the first cytogenetic proof that LGFMS and HSCT are variants of the same entity. The tumors occurred in the thighs of 2 females and in the buttock and supraclavicular fossa of 2 males. One HSCT had a spectrum of unusual histologic features, including the presence of plump epithelioid cells with abundant cytoplasm and strands and nests of clear epithelioid cells separated by eosinophilic hyalinized stroma. Two cases showed a hitherto unreported, focal staining with epithelial membrane antigen, thus adding to the immunohistochemical profile of these tumors. LGFMS and HSCT probably have a wider spectrum of morphologic features than previously thought, the awareness of which will help pathologists to avoid diagnostic pitfalls. Demonstration of the t(7;16)(q34;p11) translocation will help to diagnose difficult cases with unusual histologic features.

Adolescent↗
PubMed2003

Immunophenotype of desmoplastic small round cell tumors as detected in cases with EWS-WT1 gene fusion product.

Desmoplastic small round cell tumor is a rare tumor typically involving peritoneum. Although the histogenesis of desmoplastic small round cell tumor has yet to be elucidated, immunophenotypical and morphological analysis shows a characteristic divergent phenotype overlapping with other round cell tumors such as Ewing's sarcoma/primitive neuroectodermal tumor, rhabdomyosarcoma, small cell mesothelioma, and carcinoma. Detection of the EWS-WT1 gene fusion is characteristic of desmoplastic small round cell tumor and has been used reliably in tumor diagnosis. In this study, we evaluated the immunophenotype of 23 desmoplastic small round cell tumor cases with the EWS-WT1 gene fusion product identified by reverse transcription-polymerase chain reaction. Paraffin sections were stained with antibodies against calretinin, WT1 (C19), desmin, myoglobin, MyoD, Myf5, myogenin, placental alkaline phosphatase, cytokeratins, MIC2, HER2/neu and c-kit using standard immunohistochemical methods. Immunoreactivity was evaluated semiquantitively by light microscopy. Desmoplastic small round cell tumors showed reactivity with calretinin in 4/21, desmin in 21/23, myoglobin in 5/17, placental alkaline phosphatase in 17/21, HER2/neu in 7/18 (3+ in 1 and 1+ in 6), c-kit in 2/14, MIC2 in 13/23, WT1 in 16/23, CAM5.2 in 21/23, and AE1/3 in 16/23 cases. The most sensitive myogenic and epithelial markers are desmin and CAM 5.2. Although nuclear reactivity of the early myogenic regulatory factors (MyoD, myogenin, Myf5) was not detected, myoglobin immunoreactivity was present in 29% of desmoplastic small round cell tumors. HER2/neu overexpression (3+) and c-kit expression are uncommon in desmoplastic small round cell tumors. A panel of myogenic and epithelial markers should be used to detect the divergent phenotype in desmoplastic small round cell tumors, a key feature in the differential diagnosis. Detection of EWS-WT1 fusion becomes critical for the diagnosis when the characteristic divergent phenotype cannot be detected immunohistochemically.

Antigens, Neoplasm↗
PubMed2003

Loss of 13q14-q21 and gain of 5p14-pter in the progression of leiomyosarcoma.

Leiomyosarcomas of soft tissues are an aggressive group of tumors with a high incidence of recurrence. Little is known about the molecular genetic changes associated with clinical outcome. Therefore, we studied 28 leiomyosarcoma samples of similar grade using comparative genomic hybridization and DNA flow cytometry and identified a difference in survival time associated with ploidy status and the number of chromosomal aberrations. The average survival time was shown to decrease with increase in chromosomal aberrations identified using comparative genomic hybridization. The average survival time was shorter in the near-tetraploid group than in the diploid and triploid group. Gain of 5p14-pter was significantly more common in near-tetraploid tumors. The survival time of patients with near-tetraploidy together with gain of 5p14-pter was reduced, and 50% died within the 1st year. Furthermore, loss of 13q14-q21 was significantly more frequent in the <5-year than in the >5-year survival group (P =.01). These results suggest that 13q14-q21 loss and 5p14-pter gain at diagnosis could be used to identify patients with leiomyosarcoma who are likely to have a shorter survival time and who might benefit from early treatment intensification.

Adolescent↗
PubMed2003

Malignant gastrointestinal stromal tumor: distribution, imaging features, and pattern of metastatic spread.

PURPOSE: To investigate and describe the anatomic distribution, imaging features, and pattern of metastatic spread of malignant gastrointestinal stromal tumors (GISTs). MATERIALS AND METHODS: The medical records of all patients at our institution with a histologic diagnosis of GIST were reviewed. Two radiologists with knowledge of the diagnosis reviewed the radiologic findings by means of consensus. Sixty-seven patients underwent computed tomography, and scans of the primary tumor were available in 38 patients. RESULTS: One hundred sixteen patients with malignant GISTs were identified (76 men and 40 women; mean age, 54.6 years +/- 13.5 [SD]). The primary tumor locations in descending order of frequency were the small bowel (n = 49), stomach (n = 43), colon (n = 7), rectum (n = 6), other (n = 3), and not specified (n = 8). Mean primary tumor size was 13 cm +/- 6. Tumors were typically well defined (31 of 36 [86%]), with a heterogeneous rim of soft tissue with lower signal intensity than that of the contrast material-enhanced liver. Central fluid attenuation was seen in 24 of 36 (67%) patients. Metastases were seen in 23 of 38 (61%) patients at presentation and in 53 of 61 (87%) patients during follow-up. Spread was usually to the liver or peritoneum. Visceral obstruction rarely occurred, even in the presence of extensive peritoneal metastatic disease. Ascites was an unusual finding. CONCLUSION: Malignant GISTs are typically large, well-circumscribed, heterogeneous, centrally necrotic tumors that arise in the wall of the small bowel or stomach. They rarely obstruct viscera, despite their large size and propensity to metastasize to the liver and peritoneum.

Adult↗