Desmoid fibromatosis is a rare, nonmetastatic neoplasm marked by local invasiveness and relentless recurrence. Molecular determinants of desmoid recurrence remain obscure. β-Catenin deregulation has ...been commonly identified in sporadic desmoids although the incidence of CTNNB1 (the gene encoding β-catenin) mutations is uncertain. Consequently, we evaluated the prevalence of CTNNB1 mutations in a large cohort of sporadic desmoids and examined whether mutation type was relevant to desmoid outcome. Desmoid specimens (195 tumors from 160 patients, 1985 to 2005) and control dermal scars were assembled into a clinical data-linked tissue microarray. CTNNB1 genotyping was performed on a 138-sporadic desmoid subset. Immunohistochemical scoring was performed per standard criteria and data were analyzed using Kaplan-Meier and other indicated methods. CTNNB1 mutations were observed in 117 of 138 (85%) of desmoids. Three discrete mutations in two codons of CTNNB1 exon 3 were identified: 41A (59%), 45F (33%), and 45P (8%, excluded from further analysis because of rarity). Five-year recurrence-free survival was significantly poorer in 45F-mutated desmoids (23%, P < 0.0001) versus either 41A (57%) or nonmutated tumors (65%). Nuclear β-catenin expression was observed in 98% of specimens and intensity was inversely correlated with incidence of desmoid recurrence ( P < 0.01). In conclusion, CTNNB1 mutations are highly common in desmoid tumors. Furthermore, patients harboring CTNNB1 (45F) mutations are at particular risk for recurrence and therefore may especially benefit from adjuvant therapeutic approaches.
Although gastrointestinal stromal tumors (GISTs) harboring activating KIT or platelet-derived growth factor receptor A (PDGFRA) mutations respond to treatment with targeted KIT/PDGFRA inhibitors such ...as imatinib mesylate, these treatments are rarely curative. Most often, a sizeable tumor cell subpopulation survives and remains quiescent for years, eventually resulting in acquired resistance and treatment failure. Here, we report that imatinib induces autophagy as a survival pathway in quiescent GIST cells. Inhibiting autophagy, using RNAi-mediated silencing of autophagy regulators (ATGs) or antimalarial lysosomotrophic agents, promotes the death of GIST cells both in vitro and in vivo. Thus, combining imatinib with autophagy inhibition represents a potentially valuable strategy to promote GIST cytotoxicity and to diminish both cellular quiescence and acquired resistance in GIST patients.
Inflammatory myofibroblastic tumor (IMT) is a mesenchymal neoplasm of intermediate biological potential, which may recur and rarely metastasize. Pathologic features do not correlate well with ...behavior. Approximately 50% of conventional IMTs harbor ALK gene rearrangement and overexpress ALK, most showing diffuse cytoplasmic staining. Rare IMTs with a distinct nuclear membrane or perinuclear pattern of ALK staining and epithelioid or round cell morphology have been reported. These cases pursued an aggressive clinical course, suggesting that such patterns may predict malignant behavior. We describe 11 cases of IMT with epithelioid morphology and a nuclear membrane or perinuclear pattern of immunostaining for ALK. Ten patients were male and 1 was female, ranging from 7 months to 63 years in age (median, 39 y). All tumors were intra-abdominal; most arose in the mesentery or omentum, measuring 8 to 26 cm (median, 15 cm). Six tumors were multifocal at presentation. The tumors were composed predominantly of sheets of round-to-epithelioid cells with vesicular nuclei, large nucleoli, and amphophilic-to-eosinophilic cytoplasm. In all cases, a minor spindle cell component was present. Nine tumors had abundant myxoid stroma. In 7 cases neutrophils were prominent and in 3 cases lymphocytes were prominent. Plasma cells were often absent. Median mitotic rate was 4/10 HPF; 6 tumors had necrosis. By immunohistochemistry, all tumors were positive for ALK, 9 tumors showing a nuclear membrane staining pattern and 2 tumors showing a cytoplasmic pattern with perinuclear accentuation. Other positive markers were desmin (10 of 11), focal smooth muscle actin (4 of 8), and CD30 (8 of 8). All tumors were negative for MYF4, caldesmon, keratins, EMA, and S-100. Fluorescence in situ hybridization was positive for ALK gene rearrangement in 9 cases, and in 3 cases tested, a RANBP2-ALK fusion was detected by reverse transcription polymerase chain reaction. Ten patients underwent surgical resection; 1 patient was inoperable. Follow-up was available for 8 patients and ranged from 3 to 40 months (median, 13 mo). All patients experienced rapid local recurrences; 4 patients had multiple recurrences. Eight patients were treated with postoperative chemotherapy; 2 patients received additional radiotherapy. Two patients also developed metastases (both patients developed metastases to the liver; 1 patient developed metastases to the lung and lymph nodes as well). Thus far, 5 patients died of disease, 2 patients are alive with disease, and 1 patient, treated with an experimental ALK inhibitor, has no evidence of disease. In summary, the epithelioid variant of IMT with nuclear membrane or perinuclear ALK is a distinctive intra-abdominal sarcoma with a predilection for male patients. Unlike conventional IMT, abundant myxoid stroma and prominent neutrophils are common. These tumors pursue an aggressive course with rapid local recurrences and are frequently fatal. We propose the designation "epithelioid inflammatory myofibroblastic sarcoma" to convey both the malignant behavior of these tumors and their close relationship with IMT.
Abstract Mesenchymal to epithelial transition (MET) in carcinomas has been proposed to promote the growth of epithelial tumour cells at distant sites during metastasis. MET has also been suggested as ...an important biological and clinical process in mesenchymal tumors, sarcomas. Here we review studies on MET in sarcomas, including molecular markers, signalling mechanisms, regulation by micro RNAs and therapeutic implications. Accumulating evidences suggest that deeper investigation and understanding of MET in sarcomas would shed light on the pathogenesis of sarcomas and might lead to identification of potential clinical biomarkers for prognosis and targets for sarcoma therapeutics.
Summary Dermatofibrosarcoma protuberans (DFSP) is a cutaneous, locally aggressive spindle cell tumor of intermediate malignancy. Tumor cells are reactive for CD34 and characterized by a t(17;22) ...translocation or a supernumerary ring chromosome that results in the fusion of exon 2 of PDGFB to various exons of the COL1A1 gene. We developed a multiplex reverse transcription polymerase chain reaction (RT-PCR) assay to detect fusion transcripts for all possible COL1A1 breakpoints. Twenty-seven formalin-fixed, paraffin-embedded DFSP cases were analyzed using 18 COL1A1 forward primers and 1 exon 2 PDGFB reverse primer. Sequence analysis was performed to definitively characterize breakpoints. Results were correlated with histology, immunohistochemistry, PDGFB break-apart fluorescence in situ hybridization analysis, and cytogenetics when available. Fusion transcripts were detected by RT-PCR in all but one DFSP case. Sequencing revealed a PDGFB exon 2 breakpoint in all cases. COL1A1 breakpoints were in exons 7 (1 patient), 10 (1), 29 (2), 40 (1), 46 (3), and 49 (2), and intronic between exons 13:14 (1), 26:27 (2), 30:31 (1) 33:34 (1), 43:44 (7), 45:46 (1), and 46:47 (1). Three novel COL1A1 breakpoints were identified, intronic between exons 13:14 (1), 30:31 (1) and in exon 49 (2). There was no correlation found between breakpoints and age, sex, or histologic variants. Using this sensitive multiplex RT-PCR assay in combination with fluorescence in situ hybridization, we found COL1A1-PDGFB rearrangements appear more prevalent in DFSP than previously reported. Its detection may be particularly helpful in the differential diagnosis of atypical, fibrosarcomatous, and metastatic DFSP.
Gastrointestinal stromal tumor (GIST) is the most common sarcoma arising in the gastrointestinal (GI) tract. Imatinib mesylate (imatinib) is efficacious in treating advanced and metastatic GIST. ...Patients undergoing resection of GIST realize a highly variable median disease-free survival (DFS). In the absence of prospective data, we conducted a randomized, phase II study to assess the safety and efficacy of preoperative and postoperative imatinib for the treatment of GIST. Nineteen GIST patients undergoing surgical resection were randomized to receive 3, 5, or 7 days of preoperative imatinib (600 mg daily). Patients received postoperative imatinib for 2 years. Perioperative adverse events were compared with those in an imatinib-naïve historical control. The efficacy of imatinib was assessed by
18
fluorodeoxyglucose positron emission tomography (
18
FDG-PET), dynamic computed tomography (dCT), terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay, and DFS. Imatinib did not affect surgical morbidity as compared with an imatinib-naïve cohort (
p
≥ 0.1). Most patients responded to preoperative imatinib by
18
FDG-PET and dCT (69% and 71%, respectively). Tumor cell apoptosis increased by an average of 12% (range 0–33%) and correlated with the duration of preoperative imatinib (
p
= 0.04). Median DFS of patients treated with surgery and imatinib was 46 months (range 10–46 months). Tumor size was a predictor of recurrence after postoperative imatinib (
p
= 0.02). Imatinib appears to be safe and may be considered for patients undergoing surgical resection of their GIST. Radiographic response and tumor cell apoptosis occur within the first week of imatinib therapy.
Abstract Leiomyosarcoma is a malignant mesenchymal tumor composed of cells showing smooth muscle differentiation. This tumor usually occurs in middle-aged or older adults, and forms a significant ...percentage of retroperitoneal, vascular, extremity, and uterine sarcomas. Leiomyosarcomas are most often associated with complex karyotypes with numerous chromosomal gains and losses. Some of these cytogenetic and molecular genetic aberrations correlate with histopathologic features and clinical outcomes. Identification of genetic alterations with specific identification of oncogenes and tumor suppressor genes may lead to additional insights into the tumorigenesis of leiomyosarcoma and the opportunity to confer the benefits of targeted therapy.
Sclerosing epithelioid fibrosarcoma (SEF) is a rare aggressive fibroblastic neoplasm composed of cords of epithelioid cells embedded in a dense collagenous stroma. The reported immunophenotype of SEF ...is nonspecific. Some SEF cases show morphologic and molecular overlap with low-grade fibromyxoid sarcoma (LGFMS), suggesting a relationship between these tumor types. MUC4 has recently been identified as a sensitive and specific marker for LGFMS; MUC4 expression was also observed in 2 tumors with hybrid features of SEF and LGFMS. We investigated MUC4 expression in SEF and other epithelioid soft tissue tumors to determine (1) the potential diagnostic utility of MUC4 for SEF and (2) the association between MUC4 expression and FUS rearrangement in SEF. Whole sections of 180 tumors were evaluated: 41 cases of SEF (including 29 "pure" SEF and 12 hybrid LGFMS-SEF), 20 epithelioid sarcomas, 11 clear cell sarcomas, 11 metastatic melanomas, 10 perivascular epithelioid cell tumors, 10 alveolar soft part sarcomas, 10 epithelioid angiosarcomas, 10 epithelioid hemangioendotheliomas, 10 epithelioid gastrointestinal stromal tumors, 10 myoepithelial carcinomas, 17 ossifying fibromyxoid tumors, 10 leiomyosarcomas, and 10 biphasic synovial sarcomas. Immunohistochemical analysis was performed after antigen retrieval using a mouse anti-MUC4 monoclonal antibody. Fluorescence in situ hybridization (FISH) was performed on 33 SEF cases using FUS break-apart probes. A subset of cases was also evaluated for EWSR1 and CREB3L2/L1 rearrangements by FISH. Strong diffuse cytoplasmic staining for MUC4 was observed in 32 of 41 (78%) cases of SEF, including all 12 hybrid tumors. FUS rearrangement was detected in 8 of 21 (38%) MUC4-positive cases of SEF with successful FISH studies. The prevalence of FUS rearrangement was similar in hybrid LGFMS-SEF (2 of 6; 33%) and SEF without an LGFMS component (6 of 15; 40%). FUS rearrangement was not detected in any cases of MUC4-negative SEF. Two hybrid tumors had both EWSR1 and CREB3L1 rearrangements. MUC4 expression was also seen in 9 of 10 (90%) biphasic synovial sarcomas, predominantly in the glandular component. All other tumor types were negative for MUC4, apart from focal reactivity in 5 ossifying fibromyxoid tumors, 2 epithelioid gastrointestinal stromal tumors, and 1 myoepithelial carcinoma. MUC4 is a sensitive and relatively specific marker for SEF among epithelioid soft tissue tumors. MUC4 expression occurs more frequently than FUS rearrangement in SEF. The finding of EWSR1 and CREB3L1 rearrangements in 2 cases of hybrid LGFMS-SEF suggests that SEFs are genetically heterogenous. MUC4-positive SEFs with FUS rearrangement are likely closely related to LGFMS. MUC4-positive SEFs that lack FUS rearrangement may be related to LGFMS but could have alternate fusion partners, including EWSR1. SEF without MUC4 expression may represent a distinct group of tumors. MUC4 expression correlates with glandular epithelial differentiation in biphasic synovial sarcoma and is very limited in other epithelioid soft tissue tumors.
Staging Soft Tissue Sarcoma: Evolution and Change Kotilingam, Dhanasekaran; Lev, Dina Chelouche; Lazar, Alexander J. F ...
CA: a cancer journal for clinicians,
09/2006, Letnik:
56, Številka:
5
Journal Article
Recenzirano
Odprti dostop
Soft tissue sarcoma (STS) is an extremely heterogeneous group of rare tumors that share a putative mesenchymal cell origin. STS can occur in any soft tissue in the body, yet all share a common ...feature of primarily disseminating hematogenously, particularly to the lungs. Staging for STS is particularly useful in prognosis, design of effective multimodality treatment programs, and comparing treatment outcomes from different centers and different eras. The current iteration of AJCC STS staging includes Tumor, Grade, Node, and Metastasis with “a” indicating superficial and “b” indicating deep designations. Further opportunities to improve this process exist, particularly as molecular considerations become more apparent, and future evolution into an even more useful STS staging system can be anticipated.
Unlike melanoma, clear cell sarcoma harbors either a t(12;22)(q13;q12) recurrent translocation, resulting in an EWSR1/ATF1 chimeric gene, or less commonly a t(2;22)(q34;q12) translocation fusing ...EWSR1 and CREB1. Few studies have examined the prevalence of all chimeric types and variants to assess the usage of ancillary genetic testing in routine diagnosis. We investigated rearrangement prevalence in 17 clear cell sarcomas, two positive control cell lines, and two melanomas (negative controls). Fluorescence in situ hybridization (FISH) analysis using the LSI EWSR1 break-apart probe and a reverse transcription polymerase chain reaction (RT-PCR) assay optimized for formalin-fixed paraffin-embedded tissue to detect all four reported EWSR1/ATF1 clear cell sarcoma chimeric types and the EWSR1/CREB1 variant was performed. All 15 cases available for testing by FISH were positive for EWSR1 rearrangement including two cases with insufficient RNA for RT-PCR. Thirteen of 15 cases successfully tested by RT-PCR harbored a type 1 chimeric transcript (EWSR1 exon 8/ATF1 exon 4), of which five tumors simultaneously carried a type 2 chimeric transcript (EWSR1 exon 7/ATF1 exon 5). One case carried a type 2 transcript alone and one case contained an EWSR1/CREB1 transcript. Both control cases were positive by both techniques with one case carrying both types 1 and 2 chimeric transcripts and the other types 2 and 3 (EWSR1 exon 10/ATF1 exon 5). Consequently, both techniques are equally effective in assessing for an EWSR1 rearrangement and are useful ancillary diagnostic tests for clear cell sarcoma. They also reinforce the prevalence of this translocation in these tumors. In addition, EWSR1-CREB1 was identified in a clear cell sarcoma of soft tissue providing further evidence that this chimeric variant is not exclusive to gastrointestinal clear cell sarcomas and should be included in RT-PCR assays of soft tissue clear cell sarcomas.
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