Genetic variants and copy number changes in soft tissue leiomyosarcoma detected by targeted amplicon sequencing

Smooth Muscle Conditions of the Chest: A Clinical, Radiologic, and Pathologic Review

Smooth muscle conditions of the chest have diverse clinical and imaging manifestations and may involve nearly every thoracic structure. Differentiation among these conditions requires the integration of clinical, radiologic, and histopathologic data. Histologic examination in conjunction with immunohistochemistry is essential for differentiation from other spindle cell neoplastic mimics. Familiarity with these entities will ensure the inclusion of smooth muscle conditions in the differential diagnosis of thoracic soft tissue lesions and potentially guide the clinician in appropriate management. We review the clinical, imaging, and histopathologic features of thoracic smooth muscle-related conditions organized by the anatomic structures affected.

Multiple Chromoanasynthesis in a Rare Case of Sporadic Renal Leiomyosarcoma: A Case Report

We present the genetic profile of kidney giant leiomyosarcoma characterized by sequencing of 409 cancer related genes and chromosomal microarray analysis. Renal leiomyosarcomas are extremely rare neoplasms with aggressive behavior and poor survival prognosis. Most frequent somatic events in leiomyosarcomas are mutations in the TP53, RB1, ATRX, and PTEN genes, chromosomal instability (CIN) and chromoanagenesis. 67-year-old woman presented with a right kidney completely replaced by tumor. Immunohistochemical reaction on surgical material was positive to desmin and smooth muscle actin. Molecular genetic analysis revealed that tumor harbored monosomy of chromosomes 3 and 11, gain of Xp (ATRX) arm and three chromoanasynthesis regions (6q21-q27, 7p22.3-p12.1, and 12q13.11-q21.2), with MDM2 and CDK4 oncogenes copy number gains, whereas no copy number variations (CNVs) or tumor specific single nucleotide variants (SNVs) in TP53, RB1, and PTEN genes were present. We hypothesize that chromoanasynthesis in 12q13.11-q21.2 could be a trigger of observed CIN in this tumor.

Recurrent broad ligament leiomyosarcoma with pancreatic and thigh metastasis: a case report

BACKGROUND

Leiomyosarcoma (LMS) is an uncommon mesenchymal neoplasm, which infrequently metastasizes to pancreas and thigh. Clinical presentation and imaging findings of metastatic broad ligament LMS are often nonspecific. Complete excision plays an important role in treatment of patients with localized LMS.

CASE PRESENTATION

Here, we report a case of a 33-year-old woman with recurrent broad ligament LMS metastasizing to pancreas and thigh. Previously, she was diagnosed with broad ligament LMS and underwent hysterectomy, bilateral salpingo-oophorectomy. The disease-free interval was 2.5 years until metastases were found. Computerized tomography (CT) of abdomen and thighs, magnetic resonance imaging (MRI) of thighs and whole-body 18-fluorodeoxyglucose positron emission tomography - computed tomography (PET-CT) performed, revealed pancreatic and thigh metastasis. Ultrasonography-guided biopsy and histological examinations confirmed LMS at both the sites. Pancreatic metastasis was completely resected first. Then the patient underwent surgical resection of thigh metastasis when both chemotherapy and radiotherapy failed. She recovered well and remained free of disease recurrence in the 2 years follow-up.

CONCLUSIONS

Though imaging lacks specificity, it is a valuable asset in assessing the burden of disease and characterizing lesions while histological examination with immunohistochemistry is helpful for the diagnosis of LMS. Complete surgical resection of all metastatic sites where-ever feasible should be strongly considered in a treated case of broad ligament LMS with a durable disease-free interval.

A genomic survey of sarcomas on sun-exposed skin reveals distinctive candidate drivers and potentially targetable mutations

Sarcomas on photodamaged skin vary in prognosis and management, but can display overlapping microscopic and immunophenotypic features. Improved understanding of molecular alterations in these tumors may provide diagnostic and therapeutic insights. We characterized 111 cutaneous sarcomatoid malignancies and their counterparts, including primary cutaneous angiosarcoma (n = 7), atypical fibroxanthoma (AFX) (n = 21), pleomorphic dermal sarcoma (PDS) (n = 17), extracutaneous undifferentiated pleomorphic sarcoma (n = 8), cutaneous leiomyosarcoma (LMS) (n = 5), extracutaneous LMS (n = 9), sarcomatoid squamous cell carcinoma (spindle cell squamous cell carcinoma) (S-SCC) (n = 24), and conventional cutaneous squamous cell carcinoma (SCC) (n = 20), by next-generation sequencing (NGS) using the StrataNGS panel for copy number variations, mutations, and/or fusions in more than 60 cancer-related genes. TP53 mutations were highly recurrent in most groups. Angiosarcoma displayed previously reported MYC amplifications, as well as CCND1 gains. RB1 mutations were relatively restricted to cutaneous LMS. As previously reported, PIK3CA mutations occurred in AFX, whereas RAS activation was more frequent in PDS. CDKN2A mutations were recurrent in AFX and S-SCC, whereas PDS displayed frequent CDKN2A deletion. S-SCC displayed mutational similarity to conventional SCC. BRCA1/2 mutations were specific to tumors with disease progression. In a subset, we detected potential driver events novel to these tumor types: activating mutations in IDH2 (PDS), MAP2K1 (angiosarcoma, PDS), and JAK1 (S-SCC) and copy gains in FGFR1 (angiosarcoma, S-SCC), KIT (AFX), MET (PDS), and PDGFRA (PDS). Our findings confirm and expand the spectrum of known genomic aberrations, including potential targetable drivers, in cutaneous sarcomatoid malignancies. In addition, certain events are relatively specific to particular tumors within this differential diagnosis and hence might be diagnostically informative.