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Michal Michal

Publications and source records attributed to Michal Michal.

At least 55 records · Page 3Linked to original sources
PubMed2005

Brooke-Spiegler syndrome: report of a case with combined lesions containing cylindromatous, spiradenomatous, trichoblastomatous, and sebaceous differentiation.

Brooke-Spiegler syndrome is an autosomal dominantly inherited disease with predisposition to cutaneous adnexal neoplasms, most commonly cylindromas and trichoepitheliomas. We report a patient in whom 11 lesions were removed from the scalp and face for various reasons over a period of 3 years. The histopathological survey revealed a plethora of benign adnexal neoplasms showing apocrine, follicular, and sebaceous differentiation occurring independently and conjointly. The histopathological spectrum in our patient included cylindromas, spiradenomas, trichoepitheliomas, small nodular trichoblastomas, and lymphadenomas. Many lesions had hybrid features of two or more neoplasms. By far the most common composite tumor was spiradenocylindroma. Some spiradenocylindromas demonstrated prominent sebaceous or trichoblastomatous differentiation or both. We suggest the terms "sebaceous spiradenocylindroma" and "trichospiradenocylindroma" for these lesions. The occurrence of sebaceous and trichoblastic differentiation in spiradenocylindromas is a further proof that spiradenoma and cylindroma are not eccrine tumors but neoplasms of the folliculosebaceousapocrine unit.

Adenoma, Sweat Gland↗
PubMed2005

Hidradenoma papilliferum with oxyphilic metaplasia: a clinicopathological study of 18 cases, including detection of human papillomavirus.

Reported here are 18 cases of hidradenoma papilliferum with oxyphilic metaplasia. All patients were women ranging in age from 29 to 74 years. Each presented clinically with a small, solitary tumor in the anogenital region. Microscopically, in addition to classic histopathological features, in every case there was oxyphilic metaplasia of the constituent epithelial cells. This finding could be likened to apocrine metaplasia, a term used in breast pathology. Other histopathological findings observed in this series, analogous to benign breast disease, included sclerosing adenosis-like changes, atypical apocrine adenosis-like changes, changes corresponding to usual ductal epithelial hyperplasia, epitheliomatosis with a streaming growth pattern, lamprocyte-like changes, clear cell change of the myoepithelium, foamy histiocyte reaction, and stromal fibrosis. Immunohistochemistry inferred that in the majority of cases oxyphilic metaplasia resulted from more lysosomes, whereas numerous mitochondria were detected in only 3 cases. Using 2 different PCR methods we identified HPV in 4 of 15 cases of hidradenoma with oxyphilic metaplasia. In addition, HPV was detected in 3 of 16 conventional papillary hidradenomas used as a control group. The following HPV types were identified: 16, 31, 33, 53, and 56. The last type was found in 5 cases. More than one HPV type from a single lesion was seen in 5 cases. Our observations are consistent with previous publications noting similarities between tumors of the breast and sweat glands. Oxyphilic metaplasia, areas with solid growth, and changes simulating atypical apocrine adenosis are rare and poorly recognized in hidradenoma papilliferum and may cause diagnostic difficulties; in our cases several submitting pathologists suspected malignancy. A causal role for HPV in hidradenoma papilliferum cannot be confirmed from our results, as the detection rate is too low. The exact role of the HPV in etiology and pathogenesis of this neoplasm has yet to be determined.

Adenoma, Sweat Gland↗
PubMed2005

Dendritic cell neurofibroma with pseudorosettes lacks mutations in exons 1-15 of the neurofibromatosis type 2 gene.

Dendritic cell neurofibroma with pseudorosettes (DCNWPR) is a recently proposed variant of neurofibroma with a distinctive microscopic appearance that is produced by a pseudorosette pattern formed by small, dark, lymphocyte-like cells (Type I cells) arranged concentrically around larger cells, with pale-staining vesicular nuclei and copious faintly eosinophilic cytoplasm (Type II cells). Although DCNWPR appears not to be associated with neurofibromatosis (NF), 1 patient with DCNWPR has been described and suggested to have a form of NF because of multiple skin lesions, with 2 of them being DCNWPR as confirmed histologically. The aim of this study was to find out whether the neurofibromatosis type 2 (NF2) gene is mutated in DCNWPR. Seven histologically proven cases of DCNWPR, from which a substantial amount of archival paraffin-embedded material was available, were selected for this study. Three cases have been previously reported, including the intraneural lesion, and 4 cases were newly identified. There were 3 female and 4 male patients, ranging in age from 30 to 61 years (median, 48 yrs). All patients clinically presented with a small solitary lesion that was clinically diagnosed as fibroma or neurofibroma, and none of the patients had signs of NF. Follow-up was known for 6 patients (range, 1-5 yrs; median, 2.5 yrs) and was uneventful in each case. Microscopically, all lesions fulfilled the criteria for DCNWPR. Exons 1 to 15 of the NF2 gene were amplified by PCR using primers previously published. The amplified fragments were purified and sequenced. The obtained sequences were computer analyzed and compared with the data of the GenBank database. No mutation was identified in 5 analyzed samples from which suitable DNA had been extracted. DCNWPR appears to have no mutation in exons 1-15 of the NF2 gene. Given the relatively small number of cases studied, it seems premature to declare that a mutation of the NF2 gene is not involved in DCNWPR, as the possibility cannot be excluded that mutations were present but remained undetected because they occurred in exons that were not examined.

Adult↗
PubMed2005

Carcinoid-like pattern in sebaceous neoplasms: another distinctive, previously unrecognized pattern in extraocular sebaceous carcinoma and sebaceoma.

This report emphasizes a carcinoid-like pattern, a previously unrecognized feature in cutaneous sebaceous neoplasms. We report 7 patients with sebaceous tumors in which neoplastic cells were arranged in a trabecular and ribbon-like pattern or formed rosettes/pseudorosettes. The cases included 6 men and 1 woman, with their ages at the diagnosis ranging from 43 to 87 years (median age, 59). All patients presented with a solitary lesion. Locations were the scalp (n = 6) and forearm (n = 1). The carcinoid-like arrangement of neoplastic cells was the sole pattern in 4 cases, and in 3 cases the so-called labyrinthine/sinusoidal and/or rippled patterns were seen in addition. Sebaceous differentiation in the form of mature sebocytes varied from almost none to approximately 10%. Although the neoplasm appeared benign architecturally, the presence of cytologic atypia qualified 2 tumors as low-grade carcinomas. Four lesions represented sebaceomas, and in 1 case microscopic delineation between a carcinoma and sebaceoma was difficult. No neuroendocrine differentiation was demonstrated immunohistochemically, histochemically, and ultrastructurally. Electron microscopic examination performed in 1 case of carcinoma revealed lipid vacuoles in a minority of cells. There were no membrane-bound neuroendocrine granules. Rare cells contained peculiar large helioid inclusions. We conclude that the carcinoid-like pattern is another distinctive pattern indicative of sebaceous neoplasms. This pattern seems to be closely related to the rippled and labyrinthine/sinusoidal patterns, as exemplified by our cases, in which these arrangements sometimes occurred simultaneously.

Adenocarcinoma, Sebaceous↗
PubMed2005

Sarcoma arising in hyaline-vascular castleman disease of skin and subcutis.

We report on a case of a sarcoma arising in the hyaline-vascular variant of Castleman disease (HVCD) of the skin and subcutis. The patient was a 38-year-old man who clinically presented with a subcutaneous non-fixed cyst-like mass on his right shoulder with an unremarkable prior medical history. Histologic sections showed a biphasic tumor with numerous atretic lymphoid follicles located in the deep dermis and subcutis and a spindle-cell neoplasm mainly situated in the deep subcutis and adjacent soft tissue. The atretic lymphoid component fulfilled the criteria for HVCD, whereas the spindle-cell lesion showed all the criteria for sarcoma including nuclear atypia and frequent mitotic figures. The sarcomatous component was diffusely positive for fascin, nerve growth factor receptor, and CD34 with focal weak reactivity for CD21 and CNA.42. Stains for CD23, CD31, CD35, CD99, ALK-1, SMA, ASMA, desmin, factor XIIIa, AE1-AE3, EMA, bcl-2, S-100, Melan-A, HMB-45, Cam 5.2, and factor VIII were negative in the neoplastic spindle cells. No monoclonal population of lymphocytes was detected and we could not identify EBV or HHV-8 virus by PCR. Electron microscopy of the sarcomatous component showed spindle cells with labyrinth-like invaginations of the nucleus and numerous long, slender, interwoven cytoplasmic processes. The sarcomatous component in this case is most consistent with a poorly differentiated follicular dendritic cell sarcoma based upon the morphologic and ultrastructural findings.

Adult↗
PubMed2005

Cutaneous lymphoid hyperplasia and other lymphoid infiltrates of the breast nipple: a retrospective clinicopathologic study of fifty-six patients.

This study characterizes the clinicopathological spectrum of lymphoproliferations involving the breast nipple and/or areola. Morphologic, immunohistochemical, molecular-genetic, and clinical features of 58 specimens from 56 patients were analyzed. They were re-diagnosed as cutaneous lymphoid hyperplasia (CLH, n = 44); other benign lymphoid infiltrates (OBLI, n = 8); peripheral T-cell lymphoma, not otherwise specified (n = 1); cases with overlapping features of CLH and B-cell lymphoma (n = 3), one of them composed of spindle cells. Cutaneous lymphoid hyperplasia infiltrates were dense, composed mainly of B cells forming follicles with germinal centers (GC). Cutaneous lymphoid hyperplasia frequently showed features suggesting a malignancy as coalescing follicles with non-polarized germinal centers lacking mantle zones, and smudged infiltrates of lymphoid cells spreading into collagen (often as "Indian files"), smooth muscle, vessel walls, and nerve sheaths. Only two cutaneous lymphoid hyperplasias recurred; otherwise all patients are without disease (mean follow-up 62 months). Monoclonal rearrangement of immunoglobulin heavy chain gene was detected in five, and of T-cell receptor gamma gene in two cutaneous lymphoid hyperplasias using polymerase chain reaction (PCR), but the patients fared well too. In 47% of cases Borrelia burgdorferi was detected by polymerase chain reaction and/or serology, of which one was monoclonal. We conclude that cutaneous lymphoid hyperplasia is the most common lymphoproliferation of the breast nipple, rarely recognized clinically, and often overdiagnosed histologically as lymphoma.

Adolescent↗
PubMed2005

Mucinous carcinoma of the skin, primary, and secondary: a clinicopathologic study of 63 cases with emphasis on the morphologic spectrum of primary cutaneous forms: homologies with mucinous lesions in the breast.

We present the largest series of mucinous carcinoma involving the skin, describing the histopathologic, immunohistochemical, electron microscopic, and cytogenetic findings. Our aim was fully to characterize the clinicopathologic spectrum and compare it with that seen in the breast. In addition, we wished to reevaluate the differential diagnostic criteria for distinguishing primary mucinous carcinomas from histologically similar neoplasms involving the skin secondarily, and study some aspects of their pathogenesis. We demonstrate that primary cutaneous mucinous carcinomas span a morphologic spectrum compatible to their mammary counterparts. Both pure and mixed types can be delineated morphologically, and some lesions have mucocele-like configurations. Most lesions seem to originate from in situ lesions that may represent, using mammary pathology terminology, ductal hyperplasia, atypical ductal hyperplasia, or ductal carcinoma in situ or a combination of the three. Inverse cell polarity appears to facilitate the progression of the changes similar to lesions in the breast. The presence of an in situ component defines the neoplasm as primary cutaneous, but its absence does not exclude the diagnosis; although for such neoplasms, full clinical assessment is essential. Mammary mucinous carcinoma involving the skin: all patients presented with lesions on chest wall, breast, axilla, and these locations can serve as clue to the breast origin. Microscopically, cutaneous lesions were of both pure and mixed type, and this correlated with the primary in the breast. Dirty necrosis was a constant histologic finding in intestine mucinous carcinomas involving the skin, and this feature may serve as a clue to an intestinal origin.

Adenocarcinoma, Mucinous↗
PubMed2005

Pseudoangiomatous stromal hyperplasia in lesions involving anogenital mammary-like glands.

Pseudoangiomatous stromal hyperplasia (PASH), first reported in 1986, is nowadays a well-recognized change in the breast. We present three cases of lesions involving anogenital mammary-like glands demonstrating this feature. All patients were females (ages, 42, 43, and 53 years). Each presented with a solitary, 1.5- to 2-cm asymptomatic nodule. Locations included the perianal area, perineum, and labium majus. Histopathologically, one lesion was classified as low-grade phyllodes tumor, another as fibroadenoma, and in the remaining case PASH was found in the background of mild hyperplasia of anogenital mammary-like glands and substantial lipomatous metaplasia. In all lesions, PASH had an identical appearance to that in the breast, that is open, slit-like, often anastomosing channels devoid of erythrocytes and lined by discontinuous, often attenuated, inconspicuous cells without atypia or mitotic activity set in a hyalinized collagenous stroma. Quantitatively, PASH ranged in the above cases, forming a relatively small focus in the fibroadenoma and being quite extensive in the remaining two cases. In the phyllodes tumor, PASH areas exhibited focal hypercellularity and presence of myoid cells. In none of the cases were there cells with intranuclear inclusions or multinucleated cells. The lesions were surgically excised. Two patients with follow-up were disease-free at one and three years after the operation. As to our knowledge, PASH has not been previously described in the anogenital area, this feature seems to have been either overlooked or is genuinely rare in this location. It may occur in a preexisting lesion of anogenital mammary-like glands or may apparently by itself produce a clinically detectable lesion. The clinicopathologic features of PASH in the anogenital area seem to be identical to those in the breast.

Adult↗
PubMed2005

Ectopic sebaceous glands in the vagina.

We report a case of ectopic sebaceous glands in the upper third of the posterior wall of the vagina of a 49-year-old woman. This is, to our knowledge, the first fully documented case report of their occurrence in the vagina. The review of the literature and possible embryologic origin are discussed.

Carcinoma, Squamous Cell↗
PubMed2005

Clear cell type of renal cell carcinoma with numerous hyaline globules: a diagnostic pitfall.

A unique and never-before-published example of clear cell renal cell carcinoma (CRCC) found among 9000 primary renal cell tumors is presented. The tumor contained such a dense concentration of glassy hyaline globules (GHG) in the cytoplasm of the neoplastic cells that it overshadowed the morphology of the neoplasm. The resulting appearance of the tumor was quite misleading and different from the conventional CRCC. The GHG were 7-30 microm in diameter. They were glassy and pale to slightly eosinophilic in color in hematoxylin-eosin. The GHG stained positively with periodic acid-Schiff and negatively with silver and Hale's colloidal iron. Immunohistochemically, they were also negative for anti Mycobacterium bovis antigen. At the ultrastructural level, the GHG were formed by an amorphous mass of stellate shape. The GHG were localized within rough endoplasmic reticulum. Molecular genetically, mutation of the distal part of exon 3 of the VHL gene causing elongation of the VHL protein was found in the tumor, thus confirming the diagnosis of CRCC.

Amino Acid Sequence↗
PubMed2005

Pigmented solid-pseudopapillary neoplasm of the pancreas.

A hitherto unrecognized variant of solid-pseudopapillary neoplasm of the pancreas is reported. The tumor presented in the pancreatic head of a 57-year-old female patient. It was a well-circumscribed, encapsulated nodule measuring 27 mm in diameter, with variegated yellow to brown and gray cut surface. Histologically, the neoplasm was composed of uniform polyhedral cells arranged around delicate fibrovascular cores retaining their solid pattern in the periphery, whereas central parts of the tumor were characterized by the formation of papillae and smaller pseudocysts. Neither mitotic activity nor invasive growth were found. Immunohistochemically, tumor cells were positive for vimentin, neuron-specific enolase, and CD56, whereas they were negative in reactions with antibodies directed against other neuroendocrine markers, cytokeratins, melanocytic markers, and pancreatic amylase. In addition to these typical findings, intracellular pigmented granules were found in the darker brown zones of the tumor. They were positively stained in periodic acid-Schiff reaction after diastase digestion, sudan black B, and in Schmorl stain. In contrast, they were not stained with Fontana-Masson, Ziehl-Neelsen, and Perls stains. Ultrastructurally, the pigment consisted of dense granules with lipid droplets resembling modified lysosomes. These results exclude the possibility of a melanogenic nature of the pigment and instead determine it as lipofuscin.

CD56 Antigen↗
PubMed2005

Primary intranodal cellular angiolipoma.

Angiolipoma is a distinct, benign soft tissue tumor that most commonly occurs in young males as multiple small, subcutaneous, tender to painful nodules with predilection for the forearms. We report a case of angiolipoma that developed within a lymph node. The patient was a 67-year-old man who underwent radical retropubic prostatectomy with diagnostic pelvic lymphadenectomy because of adenocarcinoma of the prostate. The prostate and 3 lymph nodes located in the obturator fossa were removed. On gross examination, the cut surface of 1 of the lymph nodes revealed an 8 x 5 mm, ovoid, sharply demarcated, nonencapsulated, gray lesion being suspicious for adenocarcinoma metastasis. Microscopically, the major portion of the lymph node was replaced by mature metaplastic adipose tissue. The angiolipoma was seen as a well-demarcated, nonencapsulated lesion composed of numerous small blood vessels lined by monomorphous flattened or spindled endothelial cells. Many vascular lumina were filled with fibrin thrombi. There were scanty mature adipocytes. Focally, areas with increased cellularity and a suggestion of solid growth of the endothelial cells were seen. Lymph nodes are known to be a rare primary site of various tumors usually occurring in other organs. The knowledge of these tumors is important in order not to interpret them as metastatic lesions. The most recognized examples are pigmented nevi, palisading myofibroblastoma, various benign epithelial inclusions, serous cystic tumors of borderline malignancy, and hyperplastic mesothelial inclusions. As we present in this report, angiolipoma is another neoplasm whose primary occurrence in the lymph node should not be misinterpreted as a metastatic tumor or malignant vascular tumor.

Adipose Tissue↗
PubMed2005

Urothelial signet-ring cell carcinoma of the renal pelvis with collagenous spherulosis: a case report.

We present a unique case of urothelial carcinoma of the right renal pelvis. It occurred in a 58-year-old woman. The tumor was located in the renal pelvis with extension into the adjacent renal medulla and cortex. Two years after surgical excision the patient is free of recurrence and metastasis. The tumor was well demarcated, without capsule, firm, solid, and whitish on the cut surface. It was 3x4 cm in largest diameter and without signs of necroses and hemorrhages. The tumor did not infiltrate the ureter. Histologically the predominant pattern of the tumor was adenocarcinomatous differentiation, and only very rare foci of urothelial carcinoma composed of typical transitional cells were found. No signs of intestinal type of metaplasia and adenocarcinoma, changes similar to the cystitis cystica or cystitis glandularis, were found in the tumor or in its vicinity. Most of the tumor looked like solid nests composed of cells with intracytoplasmic lumens. The resulting appearance was that of typical signet-ring cell change. These solid nests were usually surrounded by columnar epithelium, which in many areas formed papillary structures. A very striking feature was formation of collagen spherules. Small collagen spherules were often surrounded by a layer of the neoplastic cells so that collagenous rosettes were formed. In some areas these collagenous spherules clustered together so that they formed areas of collagenous spherulosis. The collagen in the spherules reacted positively with collagen IV. Ultrastructurally these spherules were formed by basal membrane-like material. Intracytoplasmic lumens of the signet-ring cell change were endowed by slender microvilli at ultrastructural level.

Carcinoma, Signet Ring Cell↗
PubMed2005

Pathological complete response in advanced gastrointestinal stromal tumor after imatinib therapy.

Gastrointestinal stromal tumor (GIST) is a rare neoplasm exhibiting, in most cases, mutations of c-kit. Recently it has been demonstrated that a majority of GIST patients with c-kit mutations respond to therapy with imatinib, a c-kit tyrosine kinase inhibitor. Although the response rate in patients treated with imatinib in prospective clinical studies is above 50%, complete response is rare, and the data on the use of imatinib as neoaduvant therapy facilitating radical surgery is still scanty. Here, we report on a patient with metastatic gastric GIST who underwent surgery after 6 months of imatinib therapy. No tumor cells were detected on pathological examination of resection specimen. This case report indicates that a pathological complete response could be achieved with imatinib therapy in patients with GIST, but a wider experience and longer follow-up is necessary to appreciate the prognostic significance of pathological complete response in GIST.

Antineoplastic Agents↗
PubMed2004

Mixed epithelial and stromal tumors of the kidney. A report of 22 cases.

Mixed epithelial and stromal tumor of the kidney (MESTK) is a recently described subset of renal neoplasm that tends to occur in middle-aged and older women and is characterized by a distinctive histological appearance. To further characterize this lesion, we report the clinicopathological and immunohistochemical features of 22 additional cases from our institutional files. Grossly, the tumors ranged in size from 1 cm to 14 cm (mean 6.7 cm), were well circumscribed but unencapsulated, and showed a cystic cut surface. The tumors were composed of a spindle cell proliferation that resembled ovarian stroma, as well as an epithelial component lining the cystic structures, which usually consisted of flat to hobnailed cells typical of collecting-duct epithelium. Areas displaying features of Mullerian differentiation were also documented in 6 cases, including epithelium of endometrioid, tubal, clear cell and squamous cell type as well as one case showing an architecture that closely resembled Mullerian adenofibroma and adenosarcoma. Follow-up in 14 patients (average 4.4 years) showed no evidence of recurrence or metastasis. We believe these tumors represent the renal counterpart of similar mixed epithelial and stromal neoplasms occurring in the biliary tract and pancreas, which is also characterized by cystic structures lined by epithelium, admixed with ovarian-type stroma. The differential diagnosis for these tumors includes cystic nephroma and cystic partially differentiated nephroblastoma, which we believe to represent clinically and morphologically distinct entities from MESTK. In particular, the distinction from cystic nephroma in adult male patients is emphasized, and two cases of this entity are included in the study for comparison.

Adult↗
PubMed2004

A benign neoplasm with histopathological features of both schwannoma and retiform perineurioma (benign schwannoma-perineurioma): a report of six cases of a distinctive soft tissue tumor with a predilection for the fingers.

We present six cases of a distinctive soft tissue tumor which occurred in five women and one man. None of the patients had signs of neurofibromatosis. All tumors occurred on the fingers ( n=5) or the thenar eminence of the hand ( n=1). The mean age of the patients was 33 years. The tumors were 1-2.5 cm in diameter (mean size 1.6 cm). Three patients with follow-up were without signs of recurrence or metastasis. Microscopically the lesions were nonencapsulated and featured a multilobular architecture and both myxoid and pseudocystic change. The lobules varied in size and shape and were separated by variably thickened, dense, sclerotic/collagenous septae. The lobules were composed of two components: schwannomatous and perineuriomatous. The schwannomatous component was immunohistochemically S-100 protein positive and CD34 and EMA negative, and the perineuriomatous component had the appearance of retiform perineurioma. The perineurial parts were mostly S-100 protein and CD34 negative and EMA positive. These two components either formed separate nodules or the schwannomatous tissue surrounded the perineurial parts located in the centers of the lobules. We interpreted the lesions as hybrid tumors with features of schwannoma and retiform perineurioma.

Adult↗