Gene expression profiling identifies distinct molecular subgroups of leiomyosarcoma with clinical relevance

YesBackground: Soft tissue sarcomas are heterogeneous and a major complication in their management is that the existing classification scheme is not definitive and is still evolving. Leiomyosarcomas, a major histologic category of soft tissue sarcomas, are malignant tumours displaying smooth muscle differentiation. Although defined as a single group, they exhibit a wide range of clinical behaviour. We aimed to carry out molecular classification to identify new molecular subgroups with clinical relevance. Methods: We used gene expression profiling on 20 extra-uterine leiomyosarcomas and cross-study analyses for molecular classification of leiomyosarcomas. Clinical significance of the subgroupings was investigated. Results: We have identified two distinct molecular subgroups of leiomyosarcomas. One group was characterised by high expression of 26 genes that included many genes from the sub-classification gene cluster proposed by Nielsen et al. These sub-classification genes include genes that have importance structurally, as well as in cell signalling. Notably, we found a statistically significant association of the subgroupings with tumour grade. Further refinement led to a group of 15 genes that could recapitulate the tumour subgroupings in our data set and in a second independent sarcoma set. Remarkably, cross-study analyses suggested that these molecular subgroups could be found in four independent data sets, providing strong support for their existence. Conclusions: Our study strongly supported the existence of distinct leiomyosarcoma molecular subgroups, which have clinical association with tumour grade. Our findings will aid in advancing the classification of leiomyosarcomas and lead to more individualised and better management of the disease.Alexander Boag Sarcoma Fund

Associations between AI-Assisted Tumor Amphiregulin and Epiregulin IHC and Outcomes from Anti-EGFR Therapy in the Routine Management of Metastatic Colorectal Cancer

Purpose: High tumor production of the EGFR ligands, amphiregulin (AREG) and epiregulin (EREG), predicted benefit from anti-EGFR therapy for metastatic colorectal cancer (mCRC) in a retrospective analysis of clinical trial data. Here, AREG/EREG IHC was analyzed in a cohort of patients who received anti-EGFR therapy as part of routine care, including key clinical contexts not investigated in the previous analysis. Experimental Design: Patients who received panitumumab or cetuximab + chemotherapy for treatment of RAS wild-type mCRC at eight UK cancer centers were eligible. Archival formalin-fixed paraffin-embedded tumor tissue was analyzed for AREG and EREG IHC in six regional laboratories using previously developed artificial intelligence technologies. Primary endpoints were progression-free survival (PFS) and overall survival (OS). Results: A total of 494 of 541 patients (91.3%) had adequate tissue for analysis. A total of 45 were excluded after central extended RAS testing, leaving 449 patients in the primary analysis population. After adjustment for additional prognostic factors, high AREG/ EREG expression (n ¼ 360; 80.2%) was associated with significantly prolonged PFS [median: 8.5 vs. 4.4 months; HR, 0.73; 95% confidence interval (CI), 0.56–0.95; P ¼ 0.02] and OS [median: 16.4 vs. 8.9 months; HR, 0.66 95% CI, 0.50–0.86; P ¼ 0.002]. The significant OS benefit was maintained among patients with right primary tumor location (PTL), those receiving cetuximab or panitumumab, those with an oxaliplatin- or irinotecan-based chemotherapy backbone, and those with tumor tissue obtained by biopsy or surgical resection. Conclusions: High tumor AREG/EREG expression was associated with superior survival outcomes from anti-EGFR therapy in mCRC, including in right PTL disease. AREG/EREG IHC assessment could aid therapeutic decisions in routine practice

RT-PCR for the detection of translocations in bone and soft tissue tumours in formalin-fixed paraffin-embedded tissues

This chapter outlines the methodology for the detection of mesenchymal-tumour-specific translocations in formalin-fixed paraffin-embedded tissue (FFPET) using the reverse transcriptase-polymerase chain reaction (RT-PCR). It includes the design of appropriate primer pairs and the necessary pretreatment of the FFPET sections to give the maximum yield of analyzable RNA, in terms of both quantity and quality. © 2011 Humana Press

Surface tumours of bone

Surface tumours of bone may be a cause of confusion and diagnostic difficulty. Confusion may arise from the several descriptive adjectives used - parosteal, periosteal and juxtacortical. Diagnostic difficulties may arise from the lack of awareness of less common entities, insufficient biopsy sampling and a failure to understand the precise relationship of a lesion and the bone surface. In this review we define and classify the important lesions and indicate imaging, macroscopic and microscopic features which are useful for diagnosis.</p

Epithelioid hemangioma of bone revisited: A study of 50 cases

The clinical and pathologic features of 50 epithelioid hemangiomas of bone are analyzed. There were 29 males and 21 females who ranged in age from 10 to 75 (mean 35) years. The tumors arose in long tubular bones (40%), short tubular bones of the distal lower extremity (18%), flat bones (18%), vertebrae (16%), and small bones of the hands (8%). Nine patients (18%) had involvement of more than 1 bone. Radiographically, the lesions were lucent and well marginated. Microscopically, the neoplasms had a lobular architecture and were composed of epithelioid endothelial cells that formed obvious vascular lumina or grew in solid sheets. No hyalinized or solid appearing extracellular myxoid matrix was present. Thirty-five patients were treated with curettage, 13 patients had a local resection and 2 patients only had a biopsy. One patient had local lymph node involvement. Three patients were treated with surgery and radiation therapy. Follow-up information revealed that 4 patients experienced a local recurrence; and 1 patient developed limited involvement of a regional lymph node. Epithelioid hemangioma of bone is a benign lesion that may be multifocal and affect separate tissue and is successfully treated with curettage or marginal en bloc excision. ©2009 by Lippincott Williams &amp; Wilkins

Detection of ASPL/TFE3 fusion transcripts and the TFE3 antigen in formalin-fixed, paraffin-embedded tissue in a series of 18 cases of alveolar soft part sarcoma: Useful diagnostic tools in cases with unusual histological features

Alveolar soft part sarcoma (ASPS) is a rare malignancy; diagnostic problems may occur when cases present as a metastasis or with unusual morphologic features. In this study, a series of 18 cases with follow-up information were analysed with regard to the ASPL/TFE3 fusion transcripts and immuno-detection of TFE3 using archival formalin-fixed, paraffin-embedded tissues. Novel primers to detect ASPL/TFE3 fusion transcripts, type 1 and 2, were designed. The patients, ten female and eight male, ranged in age from 3 to 46 years; 16 involved soft tissues of the extremities (nine, lower; seven, upper), one involved the uterine cervix and one was a primary bone tumour of the foot. Seven ASPS had unusual morphologic features lacking the typical alveolar pattern. Seven had lung metastases at the time of diagnosis, and three developed lung and brain metastases later. Four patients died of disease (after 1-5 years); four are alive with metastases (after 2-15 years), and ten are alive and well (after 1-10 years). Vascular invasion correlated with metastatic disease. All 18 ASPS, four granular cell tumours (one of which was malignant) and one adrenal cortical carcinoma showed TFE3 immuno-positivity. The 18/18 ASPS showed ASPL/TFE3 fusion transcripts (nine, type 1; nine, type 2), four of which had a balanced translocation. ASPL/TFE3 fusion transcripts were not detected in 25 controls. We conclude that immuno-detection of TFE3 and RT-PCR-based identification of ASPL/TFE3 fusion transcripts in formalin-fixed, paraffin-embedded tissues are powerful tools in the diagnosis of ASPS, particularly in cases with unusual morphologic features. © Springer-Verlag 2010

BCOR-CCNB3 (Ewing-like) Sarcoma:A Clinicopathologic Analysis of 10 Cases, In Comparison With Conventional Ewing Sarcoma

BCOR-CCNB3 fusion transcripts resulting from an X-chromosomal paracentric inversion were recently identified in a series of unclassifiable soft tissue and bone sarcomas with Ewing sarcoma–like morphology. The morphologic and clinical features of these sarcomas are, as yet, not well characterized. Here we describe the clinicopathologic features of 10 cases of BCOR-CCNB3 sarcoma and compare their clinical course with typical Ewing sarcoma. Nine of 10 patients were male, and all were 11 to 18 years of age. Seven tumors were located in the bone and 3 in the deep soft tissues. The histomorphologic spectrum was quite wide, with 7 tumors predominately showing small primitive cell morphology with angulated nuclei simulating so-called atypical Ewing sarcoma and 3 predominately showing spindle cell morphology. Recurrent and metastatic lesions showed increased cellularity and marked pleomorphism. Immunohistochemistry showed expression of CCNB3 (100%), bcl2 (90%), CD99 (60%), and CD117 (60%). Reverse transcription polymerase chain reaction for BCOR-CCNB3 fusion transcripts was positive in all 9 cases, which yielded sufficient extracted RNA. Five- and 10-year survival rates were 75% and 56%, respectively. BCOR-CCNB3 sarcomas located in axial skeleton and soft tissues showed a significantly shorter survival. The Ewing sarcoma overall survival was not statistically different, although there was a trend for longer survival of patients with BCOR-CCNB3 sarcomas in the extremities. In conclusion, this study provides a detailed description of the histologic spectrum, immunohistochemical features, and clinical characteristic of BCOR-CCNB3 sarcoma justifying distinction from Ewing sarcoma with its typical EWS/FUS-ETS translocations. Ideally immunohistochemistry is used in combination with reverse transcription polymerase chain reaction for definitive diagnosis