[Myopericytoma-type perivascular myoma located in the soft tissue of the foot: a case report and review of the literature]. / Mioma perivascolare di tipo miopericitoma dei tessuti molli del piede: descrizione di un caso e revisione della letteratura.

We describe a rare case of myopericytoma-type perivascular myoma (MTPM) which arose in acral location and the literature on this field is briefly reviewed. The patient, a 68-year-old man, presented with an enlarging painful nodule, 1.4 cm across, located in the subcutaneous tissue of the right foot. The patient is alive and well 17 months after surgical excision of the nodule. Microscopically, the lesion was well-circumscribed and characterized by a biphasic pattern with a concentric perivascular spindle and ovoid cell proliferation and an extensive hemangiopericytomatous growth component. Immunohistochemically, the neoplastic cells were positive for vimentin, smooth muscle actin, desmin and calponin, negative for S-100 protein, CD34, CD31 and cytokeratins (AE1/AE3, Cam 5.2). Electron microscopy showed electrondense cell bodies suggestive for myopericytic differentiation. The clinico-pathological features of the present case are similar to those previously reported in the literature and we also discuss herein the main histological criteria for the differential diagnosis with other spindle cell and vascular lesions of soft tissues.

Alterations of P16 (MTS1) in node-positive non-small cell lung carcinomas.

The status of the P16 gene was investigated by Southern blot, polymerase chain reaction-single strand conformational polymorphism (PCR-SSCP), and DNA sequencing analyses in 30 primary resected non-small cell lung carcinomas (NSCLCs) with metastatic involvement of thoracic lymph nodes and 33 NSCLCs without node metastases. Direct sequencing of tumour DNA samples scored positive by PCR-SSCP showed five somatic mutations of the P16 gene: four nonsense and one frameshift. The Southern blot analysis revealed the presence of a homozygous deletion of the P16 locus in one tumour. All of the six NSCLCs with somatic aberrations of the P16 gene belonged to the series of tumours with metastatic diffusion to thoracic lymph nodes. In each of these six cases, the genetic aberration was seen in both the primary tumour and the node metastasis. No P16 alteration was found in tumours without metastatic lymph nodes. This difference was statistically significant (P = 0.02). No correlation was present between P16 alterations and other clinicopathological parameters including age of patients, tumour size, histological type, and grade. In three tumours with genetic aberration of P16, there was a concomitant alteration of the p53 gene. Our results indicate that the P16 gene is infrequently mutated (10 per cent of the cases examined) in primary resected NSCLC. However, since P16 mutations were found only in metastatic tumours, they may be important events in late phases of tumour progression and could represent useful markers of tumour aggressiveness in NSCLC.

[Liposarcoma of the spermatic cord. Clinical case]. / Liposarcoma del funicolo spermatico. Caso clinico.

Sarcomas are neoplasms originating from connective tissues of any anatomical region; the sarcoma of spermatic cord is a rare neoplasm with only little more than two hundred cases described in the literature. Rhabdomyosarcomas in childhood and leiomyosarcomas in adults are the most frequent histological types. Liposarcomas, fibrosarcomas and osteosarcomas are less frequent. The spermatic cord liposarcoma originates from the spermatic cord fatty tissue and therefore it consist of adipose cells, fibroblasts and myxomatosus cells; such neoplasms are usually very well differentiated. Diagnosis is suggested by the appearance of a progressively enlarging mass and by echotomography which shows a solid or liquid mass of the spermatic cord. Therapy consists of surgical intervention (orchifunicolectomy) which also allows a correct histological diagnosis. The case of a 56 year-old male who underwent left orchifunicolectomy for a sarcoma of spermatic cord occasionally discovered during surgical repair of a left groin hernia is reported. Six months after the intervention the patient is in good condition and there is no evidence of relapse.

Bronchioloalveolar lung carcinomas: K-ras mutations are constant events in the mucinous subtype.

Bronchioloalveolar carcinoma (BAC) is a form of peripheral lung adenocarcinoma growing as a single layer of malignant cells along the walls of terminal airways. The existence of BAC as a separate clinico-pathological entity has been a matter of controversy, mainly because its histogenesis is uncertain and it is not easily distinguishable from conventional lung adenocarcinoma (CLA). Three subtypes of BAC have been described using histological and cytological criteria: mucinous, non-mucinous, and sclerosing. The clinical behaviour of BAC appears to be dependent on the histological subtype. The different morphological patterns and clinical outcome of the subtypes of BAC suggest that their biological behaviour may be different from one another and from CLA. This study has investigated 58 BACs (10 mucinous, 40 non-mucinous, and 8 sclerosing) and 50 control CLAs for mutations at codon 12 of the K-ras oncogene. Twenty-one (36 per cent) BACs and 13 (26 per cent) CLAs showed K-ras mutations. A clear association (P < 0.0001) between K-ras mutations and the mucinous type of BAC was observed: all 10 mucinous tumours examined were scored positive for mutations in the K-ras gene, while only 9 (23 per cent) of the 40 non-mucinous and 2 (25 per cent) of the 8 sclerosing BACs were found to be positive. The frequency of ras mutations in non-mucinous BAC, sclerosing BAC, and CLA was not statistically different. Our data indicate that BACs are a heterogeneous group of lung tumours and that the mucinous form might represent a biological entity separate from both the other two BAC types and CLA.