Microcystic meningiomas: comparison of histology and computed tomography

INTRODUCTION: Microcystic meningiomas are defined by large vacuolated and stellate shaped cells. We recently examined a microcystic meningioma mimicking a malignant tumor on computed tomography (CT). The aim of the current study was to compare the radiological features of microcystic meningiomas with their histological patterns. METHODS: We have diagnosed 7 intracranial microcystic meningiomas among 204 meningiomas registered in the files of our Department of Pathology from 1994 to 2001. All CT scans performed before surgery were reviewed. RESULTS: Three of the microcystic meningiomas appeared as entirely microcystic tumors. Two of them were homogeneously hypodense or isodense on CT scan. The third mening was heterogeneous, containing some blood. The histologic pattern of the 4 other meningiomas showed microcystic tumor cells associated with meningothelial or fibrous tumor cells. These meningiomas were heterogeneous on CT scan. All meningiomas seemed to be connected to the dura mater. Three tumors were strongly and homogeneously enhanced after contrast media injection while 3 others were heterogeneously enhanced. No enhanced CT scan was available for 1 case. Astrocytomas were incorrectly diagnosed by CT scan in the 3 heterogeneously enhanced tumors. Meningiomas were correctly diagnosed in the 3 strongly enhanced tumors. CONCLUSION: The presence of microcystic tumour cells in meningiomas often results in erroneous diagnosis on CT scan, particularly for those which are heterogeneously enhanced. In these cases, a diagnosis of astrocytoma is often made.     

Flow cytometric analysis of antigen expression in malignant and normal renal cells

Flow cytometry allows quantitative analysis of cancer cells. The aim of this study was to make a quantitative study of antigen expression in malignant and normal renal cells in order to find the efficient monoclonal antibodies (mAbs) for labelling renal cancer cells. MATERIAL AND METHODS: 15 malignant and adjacent normal renal tissues and three renal carcinoma cell lines (ACHN, A704 and CAKI-2) were analyzed. The malignant and normal renal tissues were dissociated mechanically into cell suspension. The mAbs and isotype controls were used for immunochemical labelling. The stained cells were analyzed by flow cytometry. RESULTS: Renal tumor associated antigen G 250 was frequently detected in malignant renal cells but not in normal renal cells. Renal tumor associated antigen gp200 recognized by 66.4.C2 and PN-15 was frequently detected in malignant cells, normal renal cells and also in all three carcinoma cell lines. Epithelial antigens were strongly positive in normal renal cells. Compared with MOC 31, Ber-EP4 and E 29, W-lD9 was mostly reactive to malignant renal cells. VU-1D9 was strongly positive on ACHN and A704. The carbohydrate carcinoma antigens CA 125, DF3 and Sialyl Lewis(a) were detectable in some of the malignant and normal renal cells. Sialyl Lewis(a) could be weakly detected on ACHN and A 704. Pan-cytokeratins and cytokeratin (CK) 8 were strongly expressed in malignant and normal renal cells and in all three cell lines. CONCLUSION: Our results indicated that G 250, 66.4.Ca, PN-15, VU-1D9, MNF116 and anti-ckg were efficient mAbs for labelling renal cancer cells. Their potential clinical application by flow cytometry should be explored.     

Sentinel lymph node detection in primary melanoma with preoperative dynamic lymphoscintigraphy and intraoperative gamma probe guidance

BACKGROUND: This study assessed the value of the radioisotopic method used alone, and factors influencing relapse rates, for sentinel lymph node (SLN) mapping in primary melanoma. METHODS: One hundred and thirty-three patients with a diagnosis of melanoma (thickness greater than 0.75 mm) underwent gamma probe-directed lymphatic mapping in a prospective single-centre study. RESULTS: Mean Breslow thickness was 3 mm. At least one SLN was identified in 132 patients (mean 1.8 nodes per patient); the success rate was 99.2 per cent. Twenty-two patients (16.7 per cent) had a metastasis within the SLN. The mean tumour thickness in patients with a metastatic SLN was 4.4 mm compared with 2.7 mm for patients with a negative SLN (P < 0.001). The median time to recurrence was 20.4 months in SLN-negative patients compared with 8.5 months in those with SLN metastasis (P < 0.001). Ten (9.1 per cent) of the 110 SLN-negative patients developed recurrence. Three patients relapsed in the previously mapped lymphatic basin after a median follow-up of 27.1 months. CONCLUSION: This study confirmed the reliability and accuracy of SLN mapping using a radioisotope technique, and also the importance of the SLN as a predictive factor for survival. There was a low risk of locoregional recurrence when the SLN was not involved.     

Congenital pigmented nevus: prognosis and therapeutic possibilities]

Congenital pigmented nevi are found in approximately 1% of newborn infants. Two main factors determine their management: 1) the risk of malignancy (melanoma); 2) the aesthetic consequences, these factors being themselves dependent upon the size and the localization of the nevi. Thus, if the systematic resection of small nevi is not required, early treatment of giant nevi which carry a high risk of malignancy before the age of ten years, is highly recommended. Main methods of treatment are surgical resection (with the help of skin grafts, or cutaneous expansion or mobilization, in giant nevi), dermabrasion and curettage.     

Solid pseudopapillary tumors of the pancreas. Pathology report of 13 cases]

OBJECTIVES: Solid pseudopapillary tumors of the pancreas are exceptional. The aims of our study were to reevaluate the mode of presentation of these tumors and to analyze the role of pathological examination in diagnostic assessment and prognostic evaluation. PATIENTS: We report the clinical, radiological and pathological findings in a retrospective series of 13 patients in whom a diagnosis of solid pseudopapillary tumor of the pancreas was made between 1983 and 1997. There were 12 females (median age: 22.5 years) and one male, aged 73. RESULTS: The tumor was discovered incidentally (3 cases) or because of nonspecific digestive symptoms (10 cases). Biological data were uninformative. The tumor was pancreatic in 12 cases and duodenal in 1. In all cases, imaging techniques showed an heterogeneous lesion with no or poor vascularization. A cystic component was identified in 4 cases. Surgical resection was performed in all cases. Pathological examination showed an encapsulated tumor in 8 cases, a non-encapsulated but well-limited lesion in 3 cases and an infiltrative tumor in 2 cases. At the time of diagnosis, multiple liver metastases were present in 1 case. Mean duration of follow-up was 24 months (range: 3-168). At last follow-up, all patients, including the patient with synchronous metastatic disease, were alive, without local recurrence. CONCLUSION: Our study confirms that most cases of solid pseudopapillary tumors of the pancreas present with a suggestive clinical picture, including their occurrence in young women and their good prognosis after surgical resection. However, our results also underline the occurrence of cases presenting with unusual features, including old age, male sex, extra-pancreatic localization and malignant evolution. Histopathological examination is essential for the establishment of the diagnosis but morphological data are of little prognostic value.     

Granuloma annulare in the child]

Granuloma annulare is a benign, common, inflammatory skin lesion of unknown etiology that is seen in both adults and children. The typical lesions are single or multiple small cutaneous papules with an annular distribution. The histology is consistent with an area of fibrinoid degeneration of collagen, surrounded by palisading histiocytes and inflammatory cells. There are four clinically distinct subtypes: localized, generalized, subcutaneous and perforating. Usually a spontaneous resolution is expected. Many medical treatments have been proposed but without evidence of efficacy. The association with insulin dependent diabetes is still being discussed.