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Biomedical subjects

M Michal

Publications and source records attributed to M Michal.

At least 55 records · Page 3Linked to original sources
PubMed2004

Perineurial cells and nerve axons in gastrointestinal schwannomas: a similarity with neurofibromas. An immunohistochemical study of eight cases.

Gastrointestinal schwannoma (GIS) is a distinctive and extremely rare lesion showing some differences from conventional soft tissue schwannoma and some similarities with common soft tissue neurofibroma. Soft tissue neurofibromas and schwannomas differ by contents of specific types of nerve sheath cells, such as Schwann cells, perineurial cells and CD34+ cells. To compare GIS with these soft tissue lesions, eight cases of typical GIS were studied immunohistochemically to evaluate their nerve sheath cell types. Epithelial membrane antigen (EMA) and claudin-1 as perineurial cell markers, and neurofilament protein as a marker for intratumoral axons were used. In addition, the tumors were stained for cytokeratin, CD117 (C-KIT), alpha-muscle specific actin, S100 protein and CD34. EMA- and claudin-positive cells were seen in 2 (25%) and one lesion, respectively, thus resembling cellular composition of neurofibroma. Intratumoral neurofilament protein positive axons otherwise typical of neurofibroma were found inside 4 tumors (50%). CD34 positivity was found in 6 tumors (75%) and often revealed a diffuse pattern as seen in neurofibroma and not a zonal pattern as described in schwannomas. These results show that GIS has some features that are more typical for neurofibroma than for conventional schwannoma. In surgical pathology practice, a finding of intratumoral axons and positivity for claudin-1 and especially for EMA should not preclude diagnosis of GIS.

Adult↗
PubMed2003

Sinonasal tubulopapillary low-grade adenocarcinoma. Histopathological, immunohistochemical and ultrastructural features of poorly recognised entity.

We present the clinicopathological, histological and immunohistochemical findings of six cases of primary tubulopapillary low-grade adenocarcinoma of the sinonasal tract with ultrastructural examination in one case. Due to its unique features, we believe that primary tubulopapillary low-grade adenocarcinoma of the sinonasal tract represents a tumour entity different from any tumours generally recognised in the sinonasal region. Our cases had an equal sex incidence, with an age range of 44-76 years. The tumour has a tendency to recur, but none of our six patients developed metastases. We feel that it is important to separate this tumour entity from other types of sinonasal adenocarcinomas that exhibit a papillary growth pattern, as they frequently pursue a much more aggressive clinical course than the tumours in this study.

Adenocarcinoma↗
PubMed2003

[Less common tumors of the pleural cavity].

Among tumourous affections of the pleural cavity dominate metastatic processes while primary pleural neoplasms are relatively rare (only 5%). The authors present 4 case-records of less common primary benign pleural tumours which were operated at the Surgical Clinic of the Faculty Hospital in Plzen during 2000. Three women and one man of different age groups were involved. In three patients accidental findings were involved, in one instance in conjunction with multiple injuries, the fourth patient was examined on account of pulmonary complaints. The diagnosis was based on the skiagram and specially on the CT of the lungs, individually also other methods were used. All findings were radically eliminated--twice by thoracotomy, twice using miniinvasive procedures. Histological examination revealed twice desmoidal fibromatosis, once a benign fibrous pleural tumour and once a rare variant of Castleman's disease. The postoperative period was free from major complications, without the need of surgical revision. Two years after surgery all patients are free from detectable signs of relapse. The authors submit at the same time an integrated view on the problem of pleural neoplasias, they discuss in particular the pitfalls of the diagnosis of these lesions, possible treatment, incl. the use of suitable endoscopic methods, and the prognosis of different types of tumours. A more detailed histopathological analysis of the described findings is given.

Adult↗
PubMed2003

[Female adnexal tumor of probable Wolffian origin (Wolffian adenoma)--2 case reports and literature review].

Presented are two cases of unusual adnexal tumor described under the term "female adnexal tumor of probable wolffian origin (FATWO)" in the bibliography. One lesion was 18 cm large tumor located in the ovary in 85-year-old woman, the second one was a 5 cm large pedunculated mass arising from broad ligament in 40-year-old female. Three main structural patterns often coexisted and comprised solid or diffuse, sieve-like and tubular arrangement of spindle or epithelial cells. Cellular atypia and mitotic figures were practically absent. Clinical follow up confirmed benign behavior in both cases. Discussed is differential diagnosis and review of the literature.

Adenoma↗
PubMed2002

Sclerosing polycystic adenosis of parotid gland with dysplasia and ductal carcinoma in situ. Report of three cases with immunohistochemical and ultrastructural examination.

We describe three cases of sclerosing polycystic adenosis (SPA) of the parotid gland, a salivary condition analogous to fibrocystic disease of the breast. For the first time, immunoreactivity for oestrogen and progesterone receptors was demonstrated, suggesting a possible participation of hormone stimulation in its pathogenesis. In addition, all our cases showed foci of dysplasia of the ductal epithelium, which in one case was severe enough to amount to carcinoma in situ. This feature that has not previously been reported in SPA.

Adult↗
PubMed2002

Spindle and cuboidal renal cell carcinoma, a tumour having frequent association with nephrolithiasis: report of 11 cases including a case with hybrid conventional renal cell carcinoma/ spindle and cuboidal renal cell carcinoma components.

AIMS: We present the largest series of an unclassified subtype of renal cell carcinoma, which seems to be a distinct morphological entity and which is sometimes designated as spindle and cuboidal renal cell carcinoma. METHODS AND RESULTS: Eleven cases of spindle and cuboidal renal cell carcinoma were found among 7000 primary renal cell tumours in Pilsen's routine and consultation files. The patients were five men and six women. They ranged in age from 22 to 65 years (mean 56.8). Microscopically, the tumours were composed of two main populations of cells. First, the preponderant type of cells was formed by flattened, spindle cells with sparse cytoplasm. The second cell type was a small cuboidal cell with clear to light eosinophilic cytoplasm. Spindle-shaped cells were arranged in a fascicular pattern often reminiscent of low-grade smooth muscle tumours. Solid areas of spindle cells were also present. Small cuboidal cells formed sparse tubular structures lined by a row of single cells. In addition to all previous published cases of spindle and cuboidal renal cell carcinoma we observed an association of nephrolithiasis in our cases. It was seen in 3/11 of our patients. A previously unreported feature is the occurrence of a conventional renal cell carcinoma component in one of our cases. Seven of our patients are currently well without signs of recurrence or metastasis, one had metastasis in a regional lymph node at the time of nephrectomy, one died of an unrelated condition, and two were lost to follow-up. CONCLUSIONS: We present 11 cases of spindle and cuboidal renal cell carcinoma, which is believed to be a distinctive morphological entity. Our cases were histologically, immunohistochemically and ultrastructurally similar to the previously reported cases of spindle and cuboidal renal cell carcinoma. In contrast to all previously reported cases of spindle and cuboidal renal cell carcinoma, we observed an association with nephrolithiasis in three of our cases; moreover, one of our tumours had a conventional renal cell carcinoma component and another revealed a metastatic focus in a regional lymph node. None of our patients died of the disease. This study confirms that spindle and cuboidal renal cell carcinoma has a low malignant potential.

Adult↗
PubMed2002

[Lymphoproliferative disease after transplantation].

Herein we describe 7 cases of posttransplantation lymphoproliferative disease (PTLD), 5 in men and 2 in women (aged from 25 to 62 years), occurring from 4 months to 12 years (mean, 7 years) after transplantation. Our patients were recipients of kidney, kidney and pancreas, heart, and autologous peripheral haematopoetic stem cells. Four cases were diagnosed as monomorphic and three as polymorphic type of PTLD according to the WHO classification. Monoclonal immunoglobuline heavy chain gene rearrangement was detected in two monomorphic lesions and one polymorphic lesion by polymerase chain reaction (PCR). In the two cases of polymorphic and the one case of monomorphic PTLD, the presence of EBV was visualised by immunohistochemical staining of some transformed lymphoid cells for latent membrane protein (LMP) of EBV. The presence of type A EBV was demonstrated by PCR. The patients were treated by reduction or discontinuation of immunosuppression and by chemotherapy. In 2 cases, a part of the organ affected by lymphoma (sigmoid colon and pancreas) was surgically resected. Four patients died of causes related to PTLD (2 to 15 months after the diagnosis), mainly of infectious complications. Two other patients who achieved remission died of unrelated causes. Only the youngest man is alive and in the complete remission 10 months after the diagnosis of PTLD.

Adult↗
PubMed2002

[Metanephric adenoma. 11 case reports and detection of collagen spherules in one tumor].

Eleven cases of metanephric adenoma are reported. The tumors were selected out of 6500 tumorous and pseudotumorous lesions of the kidney in our registry. Female to male ratio was 1:1.2. The average age of the patients was 48.3 years, with a range of 13-79 years. The mean size of the tumors was 7.2 cm. The tumors were spherical in shape, whitish to yellowish in colour. Histologically, they were arranged in a mainly tubular pattern with short pseudopapillae. The tumorous cells were deeply eosinophilic to basophilic with predominantly round nuclei. Psammomatous bodies were numerous. Immunohistochemically, they reacted positively with antibodies against cytokeratins, vimentin, and WT1. Ultrastructurally, the cytoplasm contained mitochondria, RER, and ribosomes. A collagenous spherulosis, identical with those in salivary gland and mammary tumors, was revealed in one case. The spherules were located mainly inside tubular structures. Ultrastructurally, they were composed of basement membrane-like material, which was surrounded by epithelial cells. Follow-up all of our patients was negative (if known) for 10 months to 4 years.

Adenoma↗
PubMed2002

EMA+ cells in dermatofibrosarcoma protuberans. A study of 11 tumors suggesting perineurial cell differentiation.

Expression of epithelial membrane antigen (EMA) was found in 11 of 57 (19%) cases of dermatofibrosarcoma protuberans (DFSP). These tumors with EMA+ cells showed the following histological features: classical storiform pattern in all 11 cases, myxoid areas in three cases, Bednar tumor pattern in one case, and fibrosarcoma-like areas in one case. The EMA+ cells had a tendency to occur in moderately cellular and collagen-rich areas with parallel cell arrangement (4 cases) and in perivascular areas (3 cases). In such parts, a nuclear palisading and a wavy appearance of the nuclei were seen focally. One tumor contained perineurioma-like areas with whorled cell arrangement and EMA+ cells. The EMA+ cells were also found in ordinary storiform areas (6 cases), but here they were isolated and scarce. In two cases, the EMA+ cells were juxtaneural; therefore their origin from a sheath of preexisting nerves can not be excluded. Expression of EMA may reflect true perineurial cell differentiation in DFSP, as suggested previously in several ultrastructural and cytogenetic studies. The knowledge of occasional EMA positivity in DFSP is needed for a differential diagnosis between DFSP and other EMA+ soft tissue lesions.

Adolescent↗
PubMed2002

Composite dermatofibrosarcoma protuberans-giant cell fibroblastoma recurring as Bednár tumor-giant cell fibroblastoma with mucoid lakes and with amputation neuroma.

We report an unusual case of composite giant cell fibroblastoma-dermatofibrosarcoma protuberans (DFSP) that, in its second recurrence, contained a pattern of Bednár tumor (BT) and giant cell fibroblastoma (GCF). The recurrent tumor showed extreme myxoid change with creation of mucoid lakes, which mimicked a pattern of myxoid liposarcoma. One area in the recurrent lesion contained amputation neuroma overgrown with neoplastic spindle cells, which simulated a nerve sheath neoplasm. This case demonstrates common histogenesis of GCF, DFSP and BT, and it shows how broad morphological spectrum can be produced by a composite tumor, especially when the tumor includes unconventional growth pattern or additional non-neoplastic lesion.

Dermatofibrosarcoma↗
PubMed2001

[Histologic classification of kidney tumors for clinical practice in adults].

Kidney tumors represent a wide scale of histological observations. However, only angiomyolipoma can be recognised preoperatively from results of the graphical examination. Other types can be recognised only on the bases of histological examination. Completely benign tumor is oncocytoma (it represents about 5% of all kidney tumors). Angiomyolipoma (2%) is also benign, though some case reports describing its malign transformation has been published. Angiomyolipoma under 4 cm can be only monitored, the larger tumors should be resected or selectively embolised the arterial blood supply to prevent spontaneous rupture. From the group of benign tumors only cystic nephroma can be diagnosed more often (up to 1%). One of the criteria for diagnosing the renal cortical adenoma is its size under 5 mm. That is why any adenoma, which could be diagnosed by means of graphical examination and therefore clinically significant does not exist. Most of tumors are malign epithelial tumors--renal carcinomas (RC). The are classified according Heidelberg classification into 5 elementary types: clear cell, papillary, chromophobe, originating form collecting ducts and not classifiable. Clear cell (conventional) renal carcinoma (CRC) comes most often (70 to 80%), its malign potential rise with increased size of tumor and with the gradient. Five-year survival is achieved in 30-50%. Granular form of CRC carcinoma (7% of all CRC) is the equivalent of poorly differentiated PRC and it has an adverse prognosis. In contrary, the cystic form of CRC (about 6%) in benign. Papillary form of RC has the five-year survival in 84%, malignant are only tumors poorly differentiated. These are tumors with extensive necroses, which brings a fragile consistency and they can be distinguished by graphical examination. Chromophobe type of RC (5%) has the five-year survival in 90%. Poor prognosis has its sarcomatoid form, which can originate from any RC, but most frequently it is derived from the chromophobe type. The form originating from collecting ducts is highly infrequent and very malignant with the five-year survival in 20% only. The unclassified form of RC (3-5%) includes tumors not suiting to the criteria of the previous RC. Other primary renal malignant tumors (sarcomas, Wilms' tumor of adults, medullar carcinoma, carcinoid) are very rare. Comparatively frequent are metastases of other tumors (namely that of lung carcinoma) and renal impairment in leukemia, which are complication not often met by urologist.

Adult↗
PubMed2001

Meningeal nodules in teratoma of the testis.

A case of a 52-year-old man with a mature adult teratoma is reported. Beside histologically mature tissues, this teratoma contained large areas of a meningiomatous proliferation in close proximity of a peripheral nerve and glial tissue. These meningiomatous proliferations were mostly seen in the peripheral parts of the teratoma surrounding the rest of teratomatous elements and were immunohistochemically EMA-positive and S-100 protein- and cytokeratin-negative. Identical meningothelial proliferations are well known in the skin and adjacent soft tissues of the scalp, where they have variously been called sequestrated meningoceles, meningeal hamartoma, cutaneous meningiomas, rudimentary meningocele, hamartoma of the scalp with ectopic meningothelial elements, or cutaneous heterotopic meningeal nodules.

Biomarkers, Tumor↗