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M Zámecník

Publications and source records attributed to M Zámecník.

At least 19 recordsLinked to original sources
PubMed2006

Dedifferentiated mixed stromal-smooth muscle tumor of the uterus. Report of a case.

So-called dedifferentiation in mesenchymal neoplasms of the uterus is very rare. Among conventional low-grade stromal tumors only three cases of dedifferentiation were reported, whereas in mixed stromal-smooth muscle tumors the dedifferentiation was yet not described. Here we present such a case of low-grade mixed stromal-smooth muscle tumor with dedifferentiation. The tumor occurred in 52-years-old postmenopausal patient. The high-grade component representing a dedifferentiation showed morphology of undifferentiated sarcoma with myxoid change. The low-grade component with morphology of mixed stromal-smooth muscle tumor was limited to a few peripheral areas of the lesion. Immunohistochemically, the low-grade component showed typical positivity for CD10, estrogen receptor, progesterone receptor, and focal reactivity for myoid markers, whereas the dedifferentiated component expressed only vimentin, CD10 and estrogen receptor. This case demonstrates that low-grade mixed stromal-smooth muscle tumor of the uterus can dedifferentiate like a pure stromal tumor. It shows that extensive sampling/histological search may be needed for recognition of a minor component in a dedifferentiated tumor.

Female↗
PubMed2006

Sessile serrated adenomas of the large bowel. Clinicopathologic and immunohistochemical study including comparison with common hyperplastic polyps and adenomas.

Sessile serrated adenoma (SSA) is a newly characterized type of the large bowel adenoma. It arises in hyperplastic polyp (HP) and represents a precursor lesion of colorectal carcinoma with microsatellite instability. SSAs differ from common HPs by abnormal proliferation of the crypt epithelium and by nuclear atypia. We examined 15 SSAs from 15 patients. The age range was 25-80 years (average 60 years). Six patients were females and 9 were males. For comparison, we examined 10 conventional tubular adenomas and 10 common HPs with vesicular cells. The sites of SSAs were as follows: 8 in rectum, 4 in rectosigmoid colon, 1 in transverse colon, 1 next to mucinous carcinoma of ascending colon, 1 in anastomosis after resection of the transverse colon adenocarcinoma. The diameter of the lesions ranged from 5 to 12 mm. Histologically, SSAs showed asymmetrical proliferation of the epithelium, irregular shape of the crypts with their branching and some crypt dilatations especially in the basal parts of the crypts. Cellular atypia (dysplasia) was usually low. In 5 cases the nuclei were focally stratified and localized in the lower part of the cells. High-grade dysplasia was found only in SSA adjacent to mucinous adenocarcinoma. Immunohistochemically, SSAs showed secretion of gastrointestinal mucin expressing MUC2 and MUC5A. Both MUC2 and MUC5A were also positive in mucinous carcinoma. In previous studies these expressions were considered specific for serrated type of carcinogenesis. However, our study found positivity of MUC2 and MUC5A also in conventional adenomas. Expression of p53 in SSAs was minimal. SSAs have malignant potential comparable with conventional adenomas and for this reason they must be distinguished from HPs.

Adenoma↗
PubMed2006

Uterine tumor resembling ovarian sex cord tumor (UTROSCT). Report of case suggesting neoplastic origin of intratumoral myoid cells.

We report a case of double uterine tumor resembling ovarian sex cord tumor (UTROSCT). The tumor was composed of sex cord-like cords, nests and tubules, and bundles of myoid cells. The lesion was interesting especially in regard to histogenesis of intratumoral myoid cells. It is not known whether these cells are neoplastic or whether they represent preexisting myometrial smooth muscle cells entrapped into the tumor. In the present case, the sex cord-like epithelioid cells showed immunohistochemically myoid features in addition to features of epithelial, sex cord and endometrial stromal differentiation. The spindle cells expressed myoid, epithelial and endometrial stromal markers, but some of them were positive for sex cord marker calretinin. This immunophenotypic overlap between sex cord-like and myoid spindle elements indicates that the spindle cells of UTROSCT represent divergent line of differentiation of neoplastic cell rather than entrapped myometrial cells. It further expands the spectrum of possible differentiations in this polyphenotypic neoplasm.

Adult↗
PubMed2005

Autoimmune gastritis. A clinicopathologic study of 25 cases.

The histopathological diagnosis of autoimmune gastritis (AG) in its early stages can be a diagnostic challenge. Even some advanced cases with complete atrophy of the corpus mucosa may be difficult to recognize. To establish the diagnosis of autoimmune gastritis, several histological features should be assessed and combined with immunostains for enterochromaffin cell-like (ECL) cells and G-cells. The main histological criteria include a mononuclear infiltrate within the lamina propria, foci of destruction of oxyntic glands, intestinal metaplasia (IM), pyloric metaplasia, and parietal cell pseudohypertrophy. These criteria were evaluated in our series of 25 patients with achlorhydria and/or megaloblastic anemia. Some of our patients presented with nonspecific gastrointestinal symptoms. The age ranged between 46 and 79 years; one male patient was only 31 years old. Histologically, the corpus mucosa displayed in all cases chronic inflammation with focal complete IM and advanced pyloric metaplasia. In 4 patients, oxyntic glands were destructed in some sites. There was a pancreatic metaplasia of acinar type in 2 patients and a minimal focal pseudohypertrophy of parietal cells in the 31-year-old man. A tubular adenoma with a low-grade dysplasia was found in one female patient. Immunohistochemically, chromogranin-A highlighted linear or nodular hyperplasia of ECL cells in 19 patients, and adenomatoid ECL hyperplasia in one case (80%). In the remaining cases hyperplasia of ECL cells could not be recognized from their normal count. In 13 cases (52%) a few ECL cells were seen also in IM. Regarding associated pathology, in one woman with nodular ECL cell hyperplasia, a gastric carcinoid was removed endoscopically. The reaction with gastrin antibody revealed in 11 cases (44%) a small number of G cells in IM in the corpus mucosa. In 18 patients, antral mucosa was examined as well. In 8 patients, the mucosa was normal; in 10 cases, a mild chronic inactive gastritis was diagnosed, and in 15 patients G-cell hyperplasia was found. In accordance with other studies, we show that the diagnosis of AG may be established microscopically in endoscopic specimens of the gastric body mucosa when histologic features and immunohistochemical detection of ECL and G cell hyperplasia are combined.

Aged↗
PubMed2005

Gastrointestinal stromal tumor (GIST) with glandular component. A report of an unusual tumor resembling adenosarcoma.

A case of gastrointestinal stromal tumor (GIST) with an unusual glandular component is reported. The tumor was found in the gastric fundus of a 93-year-old woman. Histologically, the lesion showed a biphasic adenosarcoma-like structure. Typical low-grade spindle cell patterns of GIST were intermingled with numerous and partly cystic glands. The glandular epithelium had pyloric/foveolar-like appearance, with foci of intestinal metaplasia and low-grade dysplasia. The stromal component was immunoreactive for CD117 (c-kit) and CD34, and negative for myoid and neuroid markers. The ultrastructural examination found nondescript and undifferentiated spindle cells. The gastric mucosa and submucosa near the tumor contained a small area with features of gastritis cystica profunda, with glands similar to those present inside the tumor. Therefore, a collision of GIST and gastritis cystica profunda is suggested in the histogenesis of the lesion.

Adenosarcoma↗
PubMed2005

Adenoid basal epithelioma of the uterine cervix in 21-year-old patient. Report of a case with histologic and immunohistochemical study.

A case of adenoid basal epithelioma (ABE) of the uterine cervix in 21-year-old woman is reported. The patient's age appears to be lowest among cases of ABE reported to date. The tumor showed typical histologic features of ABE and was associated with CIN3. In addition, rare tumor cells had surface cilia-appearing structures suggesting tubal differentiation. Immunohistochemically, the tumor was reactive for p63, CD10, ER, PR, p16 and bcl-2, and negative for CEA. Thus, the immunophenotype also suggests possible partial tuboendometrioid differentiation in the glandular component of the lesion. It further indicates, along with finding of associated CIN, a role of oncogenic HPV in pathogenesis of ABE.

Adult↗
PubMed2004

Squamous cell carcinoma in situ involving mesonephric remnants of the uterine cervix.

Squamous cell carcinoma in situ (CIS) involving mesonephric remnants of the uterine cervix is a very rare lesion, the existence of which is still controversial. A second case of this lesion is reported. It was found in a cone biopsy specimen from an 40-year-old patient. Besides, in surface epithelium and within cervical glands, a structure of CIS was seen in conjunction with mesonephric tubules in deeper cervical stroma. The mesonephric nature of these tubules and of tubule-appearing epithelium within islands of CIS was supported by immunohistochemical positivity for CD10 and vimentin. The lesion strongly simulated invasive carcinomas, such as adenosquamous carcinoma and adenoid basal carcinoma (epithelioma) of the cervix.

Adult↗
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

Retroperitoneal schwannoma with features of gastrointestinal schwannoma. A case report.

A case of retroperitoneal schwannoma with histological features of gastrointestinal (GI) schwannoma occurring in a 67-year-old woman is reported. The tumor was composed of spindle cells with focal pseudoatypism and it showed several features typical of gastrointestinal-type schwannoma such as lymphocytic infiltration, peripheral cuff of lymphocytes, lack of Antoni A pattern, and absence of thick walled vessels. Immunohistochemically, the tumor showed diffuse reactivity for S100 protein and glial fibrillary acidic protein. The authors discuss a phenotypical similarity of the lesion with GI schwannoma as well as the possible existence of GI-type schwannoma outside the tubal GI tract.

Aged↗
PubMed2002

Calcifying sclerosing tumor of the ovary: a late stage of sclerosing stromal tumor?

An unusual calcifying tumor of the ovary occurring in a 23-year-old woman is described. The tumor did not produce any endocrine symptoms. Histologically, it was paucicellular and displayed extensive sclerotic stroma with numerous calcifications. The fibroblast-like cells were arranged in vague pseudolobules thus resembling overall the architecture of the sclerosing stromal tumor (SST), but the hemangiopericytoma-like vasculature typical of SST was not seen. However, immunohistochemical endothelial markers CD31 and CD34 showed a surprisingly high number of small vessels that were not apparent in hematoxylin-eosin stained sections. The tumor cells were positive for alpha-inhibin, CD99, actin, and negative for desmin, S100 protein, and epithelial markers. This type of ovarian stromal tumor may represent a calcifying stage of SST.

Adult↗
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

[Oncocytoma of the kidney--morphologic variation in 102 cases].

From the collection of 2500 cases of renal epithelial tumors in our files, 102 renal oncocytomas were analyzed for size, multifocality and a morphologic spectrum of the growth pattern. The size of the tumors ranged from 1.5 to 13 cm in diameter, with a mean of 6.3 cm. Three cases were multifocal, four cases were combined with another primary renal tumor (1x angiomyolipoma, 1x conventional renal carcinoma, 2x papillary renal cell carcinoma). A central fibrosis or a scar was noted in 13 cases, and there was a gross area of hemorrhage in 11 cases. In 4 cases extensive necroses were recognized. Histologically, an alveolar pattern was noted in 70 cases. A tubular pattern was revealed in 31 cases and an unusual tubopapillar ("glomeruloid") pattern was noted in one case. Foci of atypical nuclei were identified in 58 cases. In 4 oncocytomas broad areas of clearance of the oncocytes were found. Psammoma bodies were recognized in 9 tumors and foci of ossification were present in 4 cases. Intracellular and extracellular hyaline globules were noted in two cases. Renal oncocytoma has a variable morphologic spectrum, and its diagnosis should be based on an analysis of structural and cytologic features. Differential diagnosis of renal oncocytomas with various tumors of the kidney which contain granular cytoplasm is discussed. These tumors with granular cytoplasm include conventional renal cell carcinomas, chromophobe cell carcinomas, and rare examples of papillary renal carcinomas.

Adenoma, Oxyphilic↗
PubMed2001

Benign ectopic prostatic glands in subvesical skeletal muscle. A lesion resembling carcinoma.

In physiological instances, the prostatic acini may be intermingled with striated muscle fibers in the apex and in the anterolateral subcapsular areas of the prostate. We report an unusual lesion composed of benign prostatic glands, which were scattered between skeletal muscle fibers beneath the bladder submucosa. A 55-year-old man underwent four transurethral resections and radiation therapy for a urothelial carcinoma of the urinary bladder. Subsequently a cystectomy was performed. In the resection specimen, the prostate specific antigen-positive glands were found among the skeletal muscle bundles close to the bladder submucosa. They were seen as small groups of haphazardly scattered or isolated glands mimicking an infiltrative pattern of a prostatic adenocarcinoma. Prominent nucleoli in some glands further contributed to the worrisome appearance of the lesion. However, the high molecular weight cytokeratin 34 beta E12 exhibited basal cell layers of the glands, and the subsequent course of disease confirmed the benign nature of the lesion. The juxtaposition of the prostatic acini with the skeletal muscle out of the apex and the anterolateral subcapsular areas of the prostate should be included in the differential diagnosis of prostatic carcinoma in urinary bladder and prostate biopsies.

Carcinoma, Transitional Cell↗
PubMed2000

Aggressive angiomyxoma presenting as polyp of uterine cavity.

Aggressive angiomyxoma is a distinctive, locally aggressive tumor associated with a high risk of local recurrences that lacks metastatic potential. This tumor occurs mostly in the soft tissues of the pelvis and the perineum of adult women. It may rarely occur at less common sites, such as the vagina, urinary bladder, and soft tissue of the perineum and the perianal region in men, particularly the scrotum. We report a case of aggressive angiomyxoma presenting as an endometrial uterine polyp. To the best of our knowledge, the primary location of aggressive angiomyxoma within the uterine cavity has never been described. Immunohistochemical and ultrastructural findings support the conclusion that the progenitor cell displays myofibroblastic and fibroblastic features, with a capacity for smooth muscle differentiation.

Adult↗