P. Dal Cin

Myofibroblastoma of the breast: genetic link with spindle cell lipoma

Mammary myofibroblastoma is a rare tumour, mainly occurring in male patients. This paper describes two cases of mammary myofibroblastoma, with typical histological features, including the presence of fat cells and mast cells. Immunohistochemically, the spindle cells stained positively for desmin and CD34. Cytogenetically, both tumours showed partial monosomy 13q and in case 1, there was, in addition, partial monosomy 16q. Rearrangements affecting 13q and 16q occur typically in spindle cell lipomas. In addition to histological similarities, the hitherto unreported chromosomal changes in mammary myofibroblastoma, which are similar to the chromosomal aberrations in spindle cell lipoma, strongly suggest a link between these two tumours and are not in favour of myofibroblastoma being a primary solitary fibrous tumour of the breast. Copyright

Lesions of 13q may occur independently of deletion of 16q in spindle cell/pleomorphic lipomas.

Very recent multidisciplinary investigations have allowed for the definition among lipomas of a clinical and histological subtype called spindle cell and/or pleomorphic lipoma, possibly associated with partial monosomy 16 and anomalies of chromosome 13. In order to get nearer to the underlying critical molecular changes further multidisciplinary pathological and genetic research is indicated, to identify which chromosome(s) anomalies are crucial in the development of these tumours.

ALK expression in pseudosarcomatous myofibroblastic proliferations of the genitourinary tract

Aims : Pseudosarcomatous myofibroblastic proliferation of the genitourinary tract is rare and may develop after trauma or spontaneously. The aim of this study was to characterize further the clinicopathological features of these lesions and to examine their relationship to inflammatory myofibroblastic tumour (IMT).

Cytogenetic evidence of clonality in cutaneous benign fibrous histiocytomas: a report of the CHAMP Study Group

Aims

Two categories of synovial sarcoma defined by divergent chromosome translocation breakpoints in Xp11.2, with implications for the histologic sub-classification of synovial sarcoma

Molecular analysis of a new series of synovial sarcomas confirms that t(X;18)(p11.2;q11.2) breakpoints occur at two distinct regions on Xp designated SS1 and SS2. Breakpoint position correlates with tumor phenotype. Monophasic tumors with no evidence of glandular components have breakpoints within the SS2 region in Xp11.21, and biphasic tumors with a focal poorly differentiated or extensive glandular structure have breakpoints within the SS1 region in Xp11.23.

Synovial chondromatosis: clonal chromosome changes provide further evidence for a neoplastic disorder

Abstract Synovial chondromatosis is a rare lesion, which is still believed by most authors to be reactive rather than neoplastic. We report on a case of synovial chondromatosis with clonal chromosomal changes [43,XX,der (1) t (1;13) (p21–22;q21),-6,-13,-14, add(21) (q21)]. The presence of clonal chromosomal changes in this and in three previously reported cases suggests that synovial chondromatosis is a true neoplastic lesion.

Proliferative myositis in a child

Abstract A case of proliferative myositis in the lumbar paraspinal muscles in a 14-year-old boy is presented. Imaging investigations including plain radiograph, ultrasound, computed tomography (CT), magnetic resonance imaging (MRI), bone scan and positron emission tomography (PET) were suggestive of an inflammatory process such as myositis ossificans. The diagnosis was made by incisional biopsy. More pronounced edema, more muscle fiber necrosis and a higher cellularity were found compared to adult cases. The karyotype of the lesion was normal. Clinically, the mass disappeared spontaneously. After 24 months, asymptomatic bridging ossification between the third and fourth lumbar vertebrae was noted.

Trisomy 7 and Trisomy 8 in Dividing and Non-Dividing Tumor Cells in Dupuytren’s Disease ☆

Cytogenetic and molecular cytogenetic analysis is reported in a series of 40 tissue samples from 36 patients with Dupuytrens disease, presenting as palmar and/or finger nodules. No consistent structural chromosome changes could be found. Instead, recurrent clonal numerical abnormalities were demonstrated in 22 of 40 tissue nodules, involving trisomies of chromosome 7 or 8 and loss of the Y chromosome. In addition, we showed that trisomy 7 and trisomy 8 were also present in non-dividing cells.

PLEUROPULMONARY BLASTOMA (PULMONARY BLASTOMA OF CHILDHOOD): GENETIC LINK WITH OTHER EMBRYONAL MALIGNANCIES?

A case of pleuropulmonary blastoma (childhood variant of pulmonary blastoma) was examined using histological, immunohistochemical, ultrastructural and cytogenetic methods. The tumour consisted of undifferentiated ‘blastematous’ areas admixed with zones of rhabdomyoblastic and chondroid differentiation and fascicular areas. Desmin and S‐100 protein immunoreactivity confirmed the myogenic and cartilaginous differentiation. Ultrastructurally only undifferentiated mesenchymal cells were present. The cytogenetic analysis revealed abnormalities of 2q. Involvement of 2q has also been described in hepatoblastoma and embryonal rhabdomyosarcoma. Although further confirmation is needed, our cytogenetic findings in pleuropulmonary blastoma suggest common genetic mechanisms in some paediatric embryonal malignancies.

Cytogenetic characterization of congenital or infantile fibrosarcoma

Chromosome analysis of a congenital or infantile fibrosarcoma from the lower left leg of a 3-week-old baby girl showed only numerical changes involving chromosomes 11, 17 and 20. As three more cases with similar combinations of trisomies of the same chromosomes have been described, this report confirms that adult and congenital fibrosarcoma are cytogenetically different and trisomy 11 may be the key-event.