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M Michal

Publications and source records attributed to M Michal.

At least 91 records · Page 5Linked to original sources
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↗
PubMed2000

Retroperitoneal peripheral hemangioblastoma: a case report and review of the literature.

Central nervous system hemangioblastomas are uncommon tumors of controversial etiology that are usually found in the posterior fossa of the cranial cavity, retina, and spinal cord. Peripheral involvement is rare; only isolated case reports have been identified. We report an unusual case of hemangioblastoma involving the retroperitoneum. A 47-year-old African-American man presented with polycythemia on routine laboratory testing. Computed tomography revealed a large retroperitoneal mass near the pancreas, in a left suprarenal location, without adrenal involvement and without attachment to a nerve. Although hemangioblastoma may be associated with the von Hippel-Lindau syndrome, this patient did not have any of the stigmata of this disease. The histologic features included a highly vascular tumor with cellular areas composed of plump, pleomorphic spindled and epithelioid (stromal) cells with variable cytoplasmic lipid vacuoles and hypocellular areas with inflammatory cells and collagenous fibrils. Immunohistochemical staining showed that the tumor (stromal) cells were positive for vimentin, calponin, S-100 protein, neuron-specific enolase, and CD57 and negative for glial fibrillary acidic protein, cytokeratins, epithelial membrane antigen, CD34, HMB-45, desmin, and the actins. These morphologic and immunohistochemical findings are consistent with hemangioblastoma. To our knowledge this is the first reported case of a hemangioblastoma in this location. Based on this case we conclude that hemangioblastoma may occur in the retroperitoneum and outside of the central nervous system in a patient without von Hippel-Lindau syndrome. The immunoprofile of this case suggests that hemangioblastomas are mesenchymal neoplasms exhibiting both neural and myofibroblastic differentiation.

Hemangioblastoma↗
PubMed2000

Expression of steroid hormone receptors, their regulated proteins, and bcl-2 protein in myofibroblastoma of the breast.

AIMS: To investigate the possible role of steroid hormones in the pathogenesis of myofibroblastoma (MFB) of the breast, we analysed the immunohistochemical expression of oestrogen, progesterone, androgen receptors, their regulated proteins and bcl-2 protein in a series of this rare tumour. METHODS AND RESULTS: Paraffin-embedded sections from seven cases of MFB of the breast (five male; two female) were immunohistochemically tested for the expression of oestrogen receptor (ER), progesterone receptor (PR), androgen receptor (AR), oestrogen-regulated pS2 protein, androgen-regulated prostate-specific antigen (PSA) and bcl-2 protein. Rare cases of benign spindle cell tumours or tumour-like lesions of the breast (primitive fibromatosis, inflammatory pseudotumour, muscular hamartoma) which enter into the differential diagnosis with MFB, were also investigated and compared with MFB. All cases of MFB showed a diffuse (70-90% of neoplastic cells) and strong nuclear labelling with ER and PR, whereas AR was expressed only in three cases (two men and one woman) in about 60-70% of cells. Conversely, no immunostaining was detected for the pS2 protein and PSA. bcl-2 protein immunoreactivity was found in all cases of MFB, although with a variable degree of expression. No expression for steroid hormone receptors, their regulated-proteins and bcl-2 protein was observed in the rare benign spindle cell lesions of the breast included in this study. CONCLUSION: The in-situ detection of ER, PR and AR suggests that steroid hormones and their receptors are implicated in the pathogenesis of breast MFB. The consistent demonstration of bcl-2 protein, associated with a positive ER/PR status, provides evidence that bcl-2 may be an oestrogen-regulated protein also in MFB and that probably plays a role in the tumorigenesis. Finally, we postulate that the ER/PR and bcl-2 positive immunoprofile of MFB of the breast, in contrast to the negative profile of other rare primitive benign spindle cell lesions of the breast herein studied, might be exploited as an ancillary diagnostic aid in differential diagnosis of doubtful cases.

Actins↗
PubMed2000

Benign renal angiomyoadenomatous tumor: a previously unreported renal tumor.

We describe a unique benign tumor of the kidney in a 93-year-old man. Microscopically the tumor was composed of an intimate intermixture of epithelial component and smooth muscle tissue, which formed the stroma of the tumor. In some parts the epithelial cells in adenomatous tubular formations were endowed with clear snouts. These clear snouts had a blister-like quality and grew on the secretory cells lining the tubules. No atypias, mitoses, or pleomorphism were present in the tumor. The muscular component consisted of poorly cellular, HMB-45-negative, leiomyomatous bundles, which greatly differed from that of angiomyolipoma. It encircled the whole tumor and intimately intermingled with the epithelial component. These leiomyomatous bands formed focally abortive vessels, which had incomplete and irregular walls and lacked an elastic layer. Even more interesting was a peculiar vascularization of the tumor. All epithelial tubular structures of the tumor revealed an intimate association with small capillaries. A fine labyrinth of the capillaries rimmed the rows of the epithelial cells. To the best of our knowledge this tumor differs from all previously described.

Adenoma↗
PubMed2000

Low-grade fibromyxoid sarcoma: a report of eight cases with histologic, immunohistochemical, and ultrastructural study.

We present eight cases of low-grade fibromyxoid sarcoma (LGFS) of soft tissues. The patients, six men and two women, ranged in age from 28 to 44 years (median, 39 years). All tumors were subcutaneous. They were located in the lower extremity (three cases), inguinal/perineal region (two cases), trunk (one case), upper extremity (one case), and neck (one case). Grossly, the lesions were similar to those described in previous studies; fibrous and well circumscribed, with pseudocapsules, and without any necrosis or nodularity. In a single case of hemosiderin-rich tumor, rusty brown strips were seen on the cut surface. Histologically, the tumors were composed of alternating fibrous and myxoid areas with various cellularity and with swirling and whorled growth patterns. The cells were stellate or spindle shaped and displayed none to mild nuclear pleomorphism and hyperchromasia. Some hypercellular areas showed a fascicular or herring bone pattern similar to common fibrosarcomas. In addition to the known typical picture of LGFS, we also have seen some unusual features. The cells of myxoid areas were often arranged in rows, thus resembling ossifying fibromyxoid tumor or myxoid chondrosarcoma of soft tissues. In a single case, the tumor cells contained a large amount of hemosiderin and the cellular nests contained synovial metaplasia-like clefts. The intranuclear invaginations of cytoplasm represented another interesting finding that was present in all tumors in our series. They seem to be constant or at least frequent features of LGFS, which may assist in the differential diagnosis. The immunohistochemical and ultrastructural findings were consistent with the fibroblastic nature of LGFS. Four cases also showed features of possible histiocytic modulation of the neoplastic fibroblasts.

Adult↗
PubMed2000

Pigmented (melanotic) neurofibroma: a clinicopathologic and immunohistochemical analysis of 19 lesions from 17 patients.

Neurofibromas with melanin-laden pigmented cells are rare, accounting for less than 1% of all neurofibromas accessioned to the Soft Tissue Registry of the Armed Forces Institute of Pathology between the years 1970 and 1996. This study analyzes the clinicopathologic features associated with 19 specimens removed from 17 patients. Eleven males and six females, ranging in age from 2 to 61 years (median, 28 years), participated in the study. Nine of 15 patients whose race was provided were black. Eight patients (47%) are known to have neurofibromatosis, and two others (12%) are strongly suspected of having this disorder; two patients have similarly affected family members. Eight patients were noted to have multiple skin tumors, and in each of two cases, two pigmented neurofibromas were available for review. Two patients had hypertrichosis and cutaneous hyperpigmentation resembling a hairy nevus, and one had a café au lait spot directly overlying a pigmented neurofibroma. Tumors ranged in size from 1.7 to 50 cm in greatest dimension and involved the buttock or leg (n = 6), head or neck (n = 8), trunk (n = 2), wrist or hand (n = 2), and an unspecified site (n = 1). The neurofibromas exhibited diffuse (n = 15), combined diffuse and plexiform (n = 2), combined diffuse and intraneural epithelioid (n = 1), and nonspecific (n = 1) growth patterns. The process involved the skin (n = 14), subcutis (n = 18), and/or skeletal muscle (n = 3). Wagner-Meissner-like bodies were identified in 11 tumors, and mitoses (average, less than one mitosis per 10 high-power fields) were present in three lesions. All examples contained scattered pigmented cells with dendritic, tadpole-shaped, spindled or epithelioid morphology. These cells were positive with Fontana-Masson (nine of nine) and Warthin-Starry (pH, 3.2; four of four) stains, and were depigmented with a melanin bleach method (two of two). An iron stain was negative. The tumors had immunoreactivity for S-100 protein (11 of 11), HMB-45 ( 10 of 11), Melan-A (four of four), tyrosinase (four of four), and CD34 (four of four). Although recurrences are documented, none of the tumors are known to have undergone malignant transformation. A pigmented neurofibroma can be confused with a pigmented dermatofibrosarcoma protuberans (Bednár tumor) because the melanin-laden cells of both processes are similar. However, the latter entity exhibits a more extensive storiform growth, has greater immunoreactivity for CD34, and lacks a diffuse proliferation of S-100 protein-positive Schwann cells.

Adolescent↗
PubMed2000

A clinicopathologic study of 45 pediatric soft tissue tumors with an admixture of adipose tissue and fibroblastic elements, and a proposal for classification as lipofibromatosis.

The tumor described here as lipofibromatosis is a rare pediatric neoplasm that has been variously interpreted as a type of infantile or juvenile fibromatosis, a variant of fibrous hamartoma of infancy, and a fibrosing lipoblastoma. This report details the clinicopathologic features associated with 45 cases of this soft tissue entity. The study group consisted of 32 males, 12 females, and one person of unstated gender. The patients presented with a soft tissue mass (range, 1-7 cm) involving the hand (n = 18), arm (n = 8), leg (n = 7), foot (n = 6), trunk (n = 5), or head (n = 1). Eight tumors were evident at birth. The individuals ranged in age from 11 days to 12 years (median age, 1 yr) at the time of initial biopsy or resection. Microscopic examination revealed abundant adipose tissue with a spindled fibroblastic element that chiefly involved the septa of fat and skeletal muscle. The process generally did not cause extensive architectural effacement of fat as is common with conventional fibromatoses, and it did not have a primitive nodular fibromyxoid component as is characteristic of fibrous hamartoma of infancy. The fibroblastic element exhibited focal fascicular growth and typically had limited mitotic activity (< or = 1 mitosis/ 10 high-power fields) and cytologic atypia. Oftentimes, small collections of univacuolated cells were present at the interface between some of the fibroblastic fascicles and the mature adipocytes. The tumors entrapped vessels (n = 45), nerves (n = 44), skin adnexa (n = 16), and skeletal muscle (n = 18). Focal immunoreactivity was present in some tumors for CD99, CD34, alpha-smooth muscle actin, BCL-2, and less frequently, S-100 protein, muscle actin (HUC 1-1), and EMA. However, no reactivity was detected for desmin (D33 and D-ER- 1 clones), keratins, or CD57. Follow-up data were available for 25 individuals (median follow-up period, 6 yrs 7 mos) with regrowth of the tumor or persistent disease documented in 17 (72%). The following events were more common in the group with recurrent or persistent disease: congenital onset, male sex, hand and foot location, incomplete excision, and mitotic activity in the fibroblastic element. Although it is likely this tumor comprises part of the spectrum of what has been referred to in the literature as infantile/juvenile fibromatosis, its clinicopathologic features and, in particular, its distinctive tendency to contain fat as an integral component, warrant separate classification as a "lipofibromatosis."

Adipose Tissue↗
PubMed2000

Malignant cylindroma in Brooke-Spiegler syndrome.

A 68-year-old female patient presented with a history of gradual appearance of multiple nodules situated predominantly on the scalp and neck, with a few nodules on the trunk. The nodules began to appear at the age of 30. Family history revealed that the patient's brother, son, father and grandmother had similar cutaneous lesions. The dominant histopathological pattern was that of a cylindroma. Features of both cylindroma and spiradenoma (spiradenocylindroma) were present within the same lesion in some biopsies. Most lesions on the scalp were skin-colored with a smooth surface. The largest tumors located on the neck were tender and ulcerated. Histopathologically, these tumors had the morphology of a high-grade malignant solid neoplasm with epithelioid features.

Aged↗
PubMed2000

Adenoid cystic carcinoma of the ovary.

We describe a case of ovarian adenoid cystic carcinoma (ACC) of the left ovary in a 23-year-old woman. The tumor had the typical cribriform pattern of ACC, lacked any component of surface epithelial carcinoma, and showed myoepithelial differentiation. The features of salivary gland-type tumor seen in this case are unusual and different from those of so-called ACC-like carcinomas of the ovary, which only resemble the salivary gland tumor histologically.

Adult↗
PubMed2000

[Ovarian stromal hyperthecosis and concurrent endometrial carcinoma of the uterus].

The authors describe the case of a 50-year old patient with a hypertension, who was sterile and obese. She presented with the clinical diagnosis of "malignant corporal polyp". On microscopical examination we found an endometroid adenocarcinoma of the endometrium with focal squamous differentiation associated with bilateral stromal hyperthecosis of the ovaries. Stromal hyperthecosis of the ovaries is often associated with oestrogen and androgen hypersecretion (virilismus), obesity and hypertension. Owing to these well known features we assume that the endometroid adenocarcinoma of the uterus was caused by ovarian hyperthecosis.

Adenocarcinoma↗
PubMed2000

Kaposiform hemangioendothelioma in adult. Report of a case with amianthoid-like fibrosis and angiectases.

A rare case of kaposiform hemangioendothelioma in adult is reported. The 11 x 7 x 5 cm tumor was excised from deep subcutis of the abdominal region in 37-year-old man. No signs of Kasabach-Merritt syndrome or lymphangiomatosis were present. Besides typical pattern of kaposiform hemangioendothelioma, following unusual features were found: dilated vessels producing a gross impression of spindle cell hemangioma, areas of amianthoid-like fibrosis, and diffuse immunoreactivity for CD99. The differential diagnosis included mainly spindle cell hemangioma (hemangioendothelioma), hemangiopericytoma-like solitary fibrous tumor, and Kaposi's sarcoma.

Adult↗
PubMed1999

Nuchal-type fibroma: a clinicopathologic study of 52 cases.

BACKGROUND: Nuchal-type fibroma (NTF) usually arises in the posterior aspect of the neck. Previously published reports describe only 11 cases and provide limited clinicopathologic information. METHODS: Fifty-two examples of NTF from 50 patients were analyzed from the files of the Soft Tissue Registries of the Armed Forces Institute of Pathology in Washington, DC, and the Faculty Hospital in Pilsen, Czech Republic. RESULTS: The age of the patients ranged from 3 to 74 years (mean, 40 years). There were 41 males and 9 females. Thirty-six NTFs were located in the posterior neck region and 16 were from extranuchal sites. Two patients had had lesions excised from both a nuchal and an extranuchal location. The mean greatest tumor dimension was 3.2 cm. Microscopically, all examples had a superficial (subcutaneous and sometimes dermal) component and consisted of paucicellular, thick bundles of lobulated collagen fibers with inconspicuous fibroblasts. Entrapped adipose tissue and traumatic neuromalike nerve proliferations were typically present. Skeletal muscle infiltration was also seen in a minority of cases. Eleven of 25 patients (44%) for whom clinical information was available reportedly had diabetes. Gardner's syndrome was documented in one patient and was possibly present in two additional individuals. During follow-up, five patients had local recurrences, but none of the recurrences were destructive and all were ultimately controlled by local reexcision. CONCLUSIONS: NTF is a rare, tumorlike accumulation of collagen that often affects the posterior neck region but can also occur in a number of other sites. The process has a strong association with diabetes and also appears to be linked to Gardner's syndrome. Local recurrence probably reflects the persistence of local or systemic factors related to its pathogenesis.

Adolescent↗
PubMed1999

Myoepitheliomas of the skin and soft tissues. Report of 12 cases.

We describe 12 cutaneous and soft tissue myoepitheliomas, most of them in elderly patients. Morphologically the cutaneous and soft tissue myoepitheliomas revealed the same spectrum as their salivary gland counterparts. They were composed of a mixture of spindle, epithelioid and clear myoepithelial cells. Immunohistochemically they were positive to keratins and S-100 protein and reacted inconsistently with antibodies to smooth muscle actin. Morphologically they lacked any folliculo-sebaceous or apocrine differentiation. We believe that they are related to the eccrine type of cutaneous mixed tumours. Most cases had a benign behaviour, but 1 tumour metastasized, and the patient died of the tumour. Myoepitheliomas of soft tissues should be distinguished from other neoplasms with epithelial differentiation and from ossifying fibromyxoid tumour of soft parts, parachordoma and extraskeletal myxoid chondrosarcoma.

Adult↗