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PubMed2000

Nuclear morphology in breast cancer: is pleomorphism an illusion?

Nuclear pleomorphism is an underlying theme of cancer histology. Any medical practitioner, not just the pathologist, would have at one time or another in a Pathology practical class, looked at histopathology slides and convinced himself or herself that cancer cells indeed looked more variable in size and shape than nontumorigenic cells. However, data from our nuclear morphometric analysis of cells in breast cancer and adjacent benign tissues appears to suggest that the larger size of the cancer cell nuclei could make any change in nuclear shape and size more noticeable and apparent than their benign counterparts. We hypothesize that the phenomenon of nuclear pleomorphism is due partly to observational subjectivity.

Breast Neoplasms↗

PubMed2005

Polypoid pleomorphic sarcoma of the colon.

In contrast to common colonic epithelial neoplasms, polypoid mesenchymal tumors of the colon are extremely rare. The majority of uncommon gastrointestinal mesenchymal tumors are associated with the so-called gastrointestinal stromal tumors (GIST). We present a case of a rare colonic pleomorphic sarcoma, macroscopically mimicking a common epithelial colonic polyp, which did not match the criteria of GIST. In this case report we discuss the clinical and pathological characteristics of a rare polypoid-shaped, pleomorphic colonic sarcoma and refer a mark-off to other rare mesenchymal neoplasms of the gut.

Aged↗

PubMedDate not supplied

Ultrastructural features of pleomorphic xanthoastrocytoma: a comparative study with glioblastoma multiforme.

Eighteen tumors (15 cases) were ultrastructurally examined and compared to 11 examples of glioblastoma multiforme (GBM) [to determine the cellular nature of pleomorphic xanthoastrocytoma (PXA).] PXA, as well as GBM, were principally composed of pleomorphic astrocytes containing numerous intermediate filaments. Lipid droplets, lysosomes, and basal laminas were more numerous and fully developed in PXA, but were not specific to the tumor. Aggregates of secondary lysosomes, light microscopically evident as eosinophilic granular bodies, and ribosome-lamella complexes were exclusively seen in PXA. Also noted in PXA were centrioles, occasional Rosenthal fibers, hemidesmosomes in small number, rudimentary cell junctions, and interstitial calcifications. In addition to astrocytic constituents, 20% of PXA contained cells with neuronal features, as evidenced by the presence of dense-core granules, microtubules, and clear vesicles. In contrast, GBMs consisted solely of astrocytic cells. In the present study, the salient ultrastructural findings of PXA were largely degenerative in nature, including numerous lipid droplets and secondary lysosomes, as well as basal laminas, ribosome-lamella complexes, and occasional neuronal differentiation. The presence of basal lamina does not necessarily imply a histogenetic derivation from subpial astrocytes, in that it is also a common feature of GBM. Given the occurrence of biphenotypic, glioneuronal differentiation in some cases, PXA may be derived from a neuroepithelial stem cell. The authors conclude that PXA is fundamentally an astrocytic tumor, albeit one with a significant tendency to undergo neuronal differentiation.

Astrocytes↗

PubMedDate not supplied

Epithelioid variant of pleomorphic liposarcoma: a comparative immunohistochemical and ultrastructural analysis of six cases with emphasis on overlapping features with epithelial malignancies.

Pleomorphic liposarcoma (PL) is the least common subtype of liposarcoma, displaying a lipoblastic, malignant fibrous histiocytoma (MFH)-like and, less frequently, an epithelioid growth pattern. The epithelioid morphology in PL is still underrecognized and may closely simulate other epithelial neoplasms, mainly adrenal cortical carcinoma (ACC). No electron microscopic (EM) studies of the epithelioid variant of PL have been previously described, nor have there been studies of its immunoreactivity with A103 or alpha-inhibin. The purpose of this study is to analyze the histological, immunohistochemical, and EM features of epithelioid PL in an attempt to better explore the distinction from their epithelial mimickers, such as ACC. A panel of 5 antibodies was studied, including A103, alpha-inhibin, smooth muscle actin (SMA), AE1/AE3, and Cam 5.2. Out of 22 cases of PLs, 6 cases characterized by the presence of both epithelioid phenotype and pleomorphic lipoblasts were identified from the EM archives. There were 4 females and 2 males, with a mean age of 58 (range, 39-78). Two lesions arose in the thigh and 1 each in the abdominal wall, chest wall, anterior mediastinum, and retroperitoneum, with tumor size ranging from 7 to 17 cm (mean, 13 cm). Histologically, 2 PLs were pure epithelioid, whereas the other 4 had a mixed epithelioid and MFH-like appearance. Immunohistochemically, A103 (4/6), SMA (4/6), and AE1/AE3 (1/6) revealed a various degree of positive reactions. No immunolabeling for alpha-inhibin or Cam5.2 was detected in any case. By EM, the epithelioid areas revealed round or polyhedral cells with lipid droplets of various sizes and number, intimately apposed cell surfaces, occasional junction-like structures (4/6), and micropinocytotic vesicles (4/6). Interestingly, the ribosome-lamellar complexes, once thought to be characteristic of hairy cell leukemia but rarely seen in solid tumors, were noted in one pure epithelioid PL. When compared to the MFH-like area, rough endoplasmic reticula (RER) were less well developed, but mitochondria were more prominent in the epithelioid components. Neither mitochondria with tubulovesicular cristae nor prominent smooth endoplasmic reticula indicative of ACC were seen. Well-formed external lamina was not present. Other features to support a higher level of epithelial differentiation, such as lumen formation, microvilli, and tonofilaments, were not found. In conclusion, focal A103 reactivity in epithelioid undifferentiated tumors should be interpreted with caution before rendering the diagnosis of a primary or metastatic ACC, especially when examining biopsy specimens. The possibility of an epithelioid variant of PL must be excluded; alpha-inhibin can serve as a useful adjunct in this regard. In addition to variable intracytoplasmic fat droplets, the distinctive ultrastructural features of epithelioid variant of PL include numerous mitochondria, pinocytotic vesicles, junction-like structures, and, rarely, ribosome-lamellar complex. Despite some overlapping features, electron microscopy remains a useful tool to distinguish between epithelioid PL and ACC.

Adult↗

PubMedDate not supplied

Pleomorphic hyalinizing angiectatic tumor of soft parts: ultrastructural analysis of a case with original features.

Pleomorphic hyalinizing angiectatic tumor, a rare neoplasm of uncertain lineage resembling malignant fibrous histiocytoma and schwannoma, was first described in 1996 by M. E. F. Smith et al. (Am Surg Pathol. 20:21-29). To date, less than 100 cases have been reported in the international literature. It occurs in subcutaneous and intramuscular soft tissues of extremities or trunk in adults without sex predilection. All lesions are composed of sheets and fascicles of spindled and pleomorphic cells associated with clusters of thick-walled ectatic vessels surrounded by a perivascular hyaline material and inflammatory cells such as mast cells. About one-half of these neoplasms express CD34. No patient has developed metastases but occasional local recurrences are possible. This tumor of uncertain lineage is suggested to be an aggressive locally growing low-grade sarcoma. Only 3 cases were previously studied by electron microscopy and appeared to consist of primitive fibroblastic cells. The authors report histological and ultrastructural characteristics of a new case of PHAT excised from the right buttock of a 66-year-old man with the presence of ganglion-like cells, a feature that has not been previously reported, and unusual central ischemic necrosis. The features of this case are suggestive of a fibroblastic origin.

Aged↗

PubMed1988

Fine-needle aspiration biopsy of pleomorphic (giant cell) carcinoma of the pancreas. Cytologic, immunocytochemical, and ultrastructural findings.

Four cases of pleomorphic (giant cell) carcinoma (PGC) of the pancreas, diagnosed by fine-needle aspiration biopsy, are presented. Ancillary immunocytochemical studies were also performed on the smears (four cases) and cell blocks (three cases), along with ultrastructural (electron microscopic) examination of the aspirated specimen (two cases). Three of the four patients were elderly (age range: 44-65 years), and all had large pancreatic masses. A spectrum of cytomorphologic features was encountered, including poorly cohesive bizarre mononuclear cells, many multinucleated tumor giant cells, and associated malignant spindle cells. Prominent cellular cannibalism and cytophagocytosis also were seen. Immunoperoxidase studies demonstrated dual staining of the malignant cells for cytokeratin and vimentin in two cases and exclusive staining for vimentin in the remaining two cases. Ultrastructural examination demonstrated epithelial features in both cases studied. One of the cases demonstrated intracytoplasmic whorled bundles of intermediate filaments, corresponding to pale eosinophilic globular material, appreciated both in the Diff-Quik- and Papanicolaou-stained smears and staining with positive results for vimentin. The immunocytochemical studies suggest that the coexpression of vimentin and cytokeratin within the cells is consistent with a pleomorphic malignancy of epithelial origin. It is speculated that the staining of two of the cases exclusively for vimentin can be seen in either epithelial malignancies with sarcomatoid transformation or, less likely, a pure sarcoma of the pancreas.

Adult↗

PubMed2001

Pleomorphic xanthoastrocytoma: favorable outcome after complete surgical resection.

To describe the clinical features, histologic characteristics, and management of patients with pleomorphic xanthoastrocytoma (PXA), we reviewed data on 13 children who had histologically confirmed PXA and were referred to the neuro-oncology service between 1985 and 1999. Neuro-imaging with CT and/or MRI documented the anatomic location, tumor extent, and degree of resection. There were 3 males and 10 females; median age was 12.9 years (range, 8.2-17.2 years). The most frequent presentations included seizures (n = 8) and headache (n = 5). Tumor sites included temporal (n = 5), parietal (n = 3), frontal (n = 1), frontoparietal (n = 1), parietooccipital (n = 1), and temporoparietal (n = 1) lobes and the spinal cord (n = 1). CT/MRI revealed a cystic component in 6 patients, with cyst wall enhancement in 3 patients. The solid component was uniformly enhancing in 11 patients. Vasogenic edema was present in 9 patients, and calcification was noted in 4 patients. Histopathologic findings included meningeal invasion in 12 patients, calcifications in 4, and necrosis in 2. Mitotic figures (1-12 per high-power field) were seen in 8 patients. Gross total resection was achieved in 8 patients, near total resection in 1, and subtotal resection in 4. Ten patients were alive with a median follow-up of 41 months at this writing. Two patients died of progressive disease, and 1 died of an unrelated cause. In conclusion, pleomorphic xanthoastrocytoma is a rare neoplasm in childhood, commonly presenting with seizures. Gross total resection without adjuvant therapy provides prolonged disease control, as seen in 6 of 7 patients (85%) in our series.

Adolescent↗

PubMed1989

Value of induction of pleomorphic ventricular tachycardia during programmed stimulation.

The morphology of the first documented, the recurrent and the induced ventricular tachycardia were studied in 41 patients with an old myocardial infarction and documented sustained ventricular tachycardia. During a mean follow-up of 29 +/- 11 months recurrent ventricular tachycardia was present in 24 of 41 patients with the same morphology as the first ventricular tachycardia in nine (37.5%) and a different morphology in 15 patients (62.5%). Ventricular tachycardia with the same morphology as the spontaneous ventricular tachycardia were induced without significant differences between patients with recurrent events and those without. However, multiple morphologies of ventricular tachycardia (pleomorphism) were induced more frequently in patients with subsequent recurrence of ventricular tachycardia (off drugs: 9 of 13, 69%, on drugs: 14 of 23, 61%) than in patients without (off drugs: 4 of 10, 40%, on drugs: 2 of 11, 18%) (P less than 0.05). Pleomorphism of ventricular tachycardia induced during programmed stimulation identifies patients at a higher risk of subsequent recurrent events. Recurrent ventricular tachycardia has a different morphology than the first one in two thirds of patients.

Aged↗

PubMed1999

Pleomorphic T-cell infiltrate associated with molluscum contagiosum.

The authors observed a pleomorphic lymphocytic infiltrate composed of CD8 cytotoxic/suppressor T-cells in two pediatric cases associated with molluscum contagiosum. T-cell clonality was not detected. In both cases, the lesions resolved after the biopsy was performed. The patients were otherwise healthy, and no evidence of lymphoproliferative process was detected on follow-up. The authors believe the pleomorphic lymphoid infiltrate is inflammatory and reactive in nature. The close apposition of lymphocytes to molluscum bodies and cytoid bodies with high expression of CD30 and the proliferating marker Ki67 is suggestive of a cytotoxic cell-mediate blastic reaction against poxvirus antigens.

Antigens, CD20↗

PubMed1994

Dedifferentiated liposarcoma. Clinicopathologic analysis of 32 cases suggesting a better prognostic subgroup among pleomorphic sarcomas.

Dedifferentiated liposarcoma is uncommon, and only a small number of cases have been documented. We describe the clinicopathologic features in a series of 32 cases. All patients were adults (age range, 37-83 years; median, 67 years); 20 were men and 12 were women. Commonest site was the retroperitoneum (fifteen cases); six cases arose in the limbs, four in the paratesticular region, three in the peritoneal cavity, two on the trunk, and one each in the buttock and larynx. One primary tumor was subcutaneous. Thirty tumors arose de novo (i.e., combined with well-differentiated tumor in the primary lesion), while two developed in recurrences of a previously well-differentiated liposarcoma. The well-differentiated component was most often lipoma-like and typically there was a histologically abrupt transition to spindle celled nonlipogenic tumor. The dedifferentiated component most often resembled either storiform "malignant fibrous histiocytoma" ("MFH") with limited pleomorphism or myxofibrosarcoma (myxoid "MFH"); the latter pattern is rarely otherwise seen in the retroperitoneum. A small number of cases showed appearances reminiscent of myxoid embryonal rhabdomyosarcoma. An unusual feature in three cases was the occurrence of a discontinuous micronodular pattern of dedifferentiation. Average follow-up of 5.6 years (range, 3 months to 33 years) in 27 cases have revealed local recurrence in 14 patients and systemic metastases in only four patients. The primary sites of the metastasising cases were upper back, thigh, retroperitoneum, and paratesticular region. There have been only seven tumor-related deaths. Good prognosis in de novo dedifferentiated liposarcomas seems unrelated to the extent or morphologic pattern of dedifferentiation. However, high mitotic activity in the dedifferentiated component was associated with a more aggressive clinical course. Our study underlines that dedifferentiation in peripherally located or even subcutaneous liposarcomas does occur, albeit rarely, and that dedifferentiated liposarcomas of the limbs may metastasize. The results suggest that dedifferentiated liposarcomas, as a subgroup among the "MFH-like" sarcomas, have a better prognosis than pleomorphic sarcomas as a whole.

Adult↗

PubMed1996

Divergent differentiation in pleomorphic xanthoastrocytoma. Evidence for a neuronal element and possible relationship to ganglion cell tumors.

We report the detection of cytoplasmic immunoreactivity for neuronal/neuroendocrine antigens in a subpopulation of tumor cells within seven pleomorphic xanthoastrocytomas (PXAs). The expression of glial and neuronal polypeptides was examined in routinely prepared surgical resections by immunohistochemistry using well-characterized antibodies that recognize glial fibrillary acidic protein (GFAP), synaptophysin (SYN), and neurofilament triplet polypeptides (NFPs) in microwave-enhanced single- and double-immunolabelling experiments. Each neoplasm contained cells that were immunoreactive for SYN and/or NFPs, GFAP, and occasionally for both GFAP and either NFP or SYN. We conclude that abortive neuronal/neuroendocrine differentiation may occur in PXAs, suggesting a relationship between PXA and other developmental neoplasms that reveal a more overt neuronal phenotype, such as ganglioglioma, dysembryoplastic neuroepithelial tumor, and desmoplastic ganglioglioma, and with tumors expressing ambiguous glial/neuronal lineage, such as the subependymal giant cell tumor of tuberous sclerosis. These findings suggest that aberrant expression and accumulation of neuronal intermediate filaments may account for the large, pleomorphic cell morphology observed in many of these tumors.

Adolescent↗

PubMed2000

Pleomorphic lobular carcinoma: morphology, immunohistochemistry, and molecular analysis.

Infiltrating pleomorphic lobular carcinoma (PLC) is an aggressive variant of infiltrating lobular carcinoma. Recently, in situ changes identical to PLC (PLCIS) have been described. The role of prognostic markers and their correlation with therapeutics, clinical outcome, and genetic changes is not well established in PLC. The authors examined 38 cases of this entity to understand better this tumor's biology. Immunohistochemical (IHC) analysis was performed in 21 specimens for estrogen and progesterone steroid receptors, p53, Her 2 (p185), and GCDFP-15. Genomic deoxyribonucleic acid was obtained from microdissected tumor as well as normal control cells, and loss of heterozygosity was investigated at the ESR (16q24), p53 (TP53 17p), Her 2 (17q 11-12), and BRCA 1 (17q12-25) loci. In this series, the average patient age was 57.5 years (age range, 24-92 years). Twenty-seven women were postmenopausal. Tumor size ranged from 1.2 to 25 cm. Six patients were a pathologic stage I; 19, stage II; 12, stage III; and one, stage IV. Histologically, multifocal nodular aggregates of discohesive pleomorphic tumor cells were seen interspersed in dense and fibrotic breast parenchyma. Twenty-nine percent of the specimens demonstrated associated signet ring cells. The remainder had dishesive, globoid, plasmacytoid cells with high-grade nuclear features. PLCIS was identified in 17 of 38 patients (45%), and lobular carcinoma in situ (LCIS) was noted in 8 patients (21%). IHC analysis showed estrogen immunoreactivity in 81%, progesterone in 67%, GCDFP-15 in 71%, and Her 2 in 81% (2+ to 3+ membranous staining) of specimens. Antibodies to p53 stained the tumor cell nuclei in 48% of the tumors. Loss of heterozygosity was identified in 52% of the specimens at the p53 locus, 18% at the ESR locus, 19% to 24% at the Her 2 loci, and 27% to 32% at the BRCA 1 locus. Follow-up was available in 19 patients and ranged from 12 months to 15 years (mean, 73 months). Seven patients had no evidence of disease at last examination (range, 1-15 years), three patients were alive with disease (range, 2-14 years), and nine patients were dead of disease (range, 2 months-9 years). Six patients had subsequent diagnoses of tumor in the contralateral breast. Analysis shows that PLC tends to appear in older postmenopausal women who present with locally advanced disease. PLCIS was found to be associated with PLC 45% of the time. The aggressive clinical course of patients with PLC is supported by tumor immunoreactivity with unfavorable markers Her 2 and p53. Overexpression of Her 2 in PLC may be therapeutically relevant, enabling the use of novel chemotherapeutic drugs like Herceptin. Interestingly, tumors that were Her 2 immunoreactive also maintained estrogen hormone immunoreactivity.

Adult↗

PubMed2002

Pleomorphic liposarcoma: clinicopathologic, immunohistochemical, and follow-up analysis of 63 cases: a study from the French Federation of Cancer Centers Sarcoma Group.

The clinicopathologic and immunohistochemical features of 63 pleomorphic liposarcomas are presented. There were 35 men and 28 women (median age 63 years; range 18-93 years). Tumor size ranged from 2 to 23 cm (median 10 cm). Tumor locations included lower extremity (36.5%), especially the thigh (28.5%), limb girdles (17.5%), upper extremity (16%), thoracoabdominal wall (9.5%), and internal trunk (20.5%). A total of 75% were deep seated and/or extracompartmental. Histologically, lesions show a varying combination of lipogenic and nonlipogenic areas characterized by malignant fibrous histiocytoma-like, round cell liposarcoma-like, and/or epithelioid/carcinoma-like features. A pericytic pattern was focally present in 15 (24%) tumors. Eighteen (29%) lesions were grade 2, and 45 (71%) were grade 3 sarcomas. Tumor necrosis was observed in 51 (81%) cases, vascular invasion in three, and mitotic counts ranged from 3 to 124 per 10 high power fields (median 25). Lipogenic areas were S-100 protein immunoreactive, at least focally, in 20 of 42 (48%) cases. Nonlipogenic areas showed focal reactivity for smooth muscle actin (24 of 49; 49%), desmin (9 of 48; 19%), CD34 (18 of 45; 40%), S-100 protein (5 of 49, 10%), CD68 (6 of 46, 13%), and epithelial membrane antigen (13 of 49, 26.5%). Epithelioid areas showed epithelial membrane antigen (4 of 11; 36%) but not cytokeratin (0 of 11) reactivity. Treatment procedures in 51 patients consisted of simple tumorectomy (16) and wide excision (33). Five and 31 patients received neoadjuvant and adjuvant chemotherapy and/or radiation therapy, respectively. Follow-up (48 patients, range 7-276 months; median 38 months) showed a 45% local recurrence rate and a 42.5% metastasis rate, metastases occurring mostly in lungs and pleura. Seventeen patients (35%) died of disease, of whom none was metastatic at diagnosis. Five-year overall, metastasis-free, and local recurrence-free survivals were 57%, 50%, and 48%, respectively. Patient age > or =60 years, truncal tumor location, deep situation, tumor size >5 cm, vascular invasion, and incomplete tumor excision were significant adverse prognostic factors. Tumor grade and histology did not affect patient outcome. In conclusion, pleomorphic liposarcoma is a rare, often deep-seated and limb-based aggressive and metastasizing neoplasm of late adulthood. It shows a wide range of morphologic appearances, but tumor grade and histology have no effect on patient outcome.

Adolescent↗

PubMedDate not supplied

MRI of temporal lobe pleomorphic xanthoastrocytoma.

Pleomorphic xanthoastrocytomas (PXA) are classically supratentorial, peripherally located, well-circumscribed, partially cystic neoplasms, which can enhance on CT following the administration of intravenous contrast agents. Focal calcification may also be seen. Although the CT appearance has been described, we report the MR findings in two cases of histologically documented temporal lobe PXA. The two well-circumscribed lesions were predominantly cystic and both contained a Gd-DTPA enhancing mural nodule. The latter was isointense with gray matter on T1-weighted images and hyperintense on T2-weighted scans. Minimal surrounding edema was present. Histologically, PXA may be confused with glioblastoma multiforme (GBM) due to the pronounced cellular pleomorphism. Because of their potentially more indolent behavior compared with GBM, it is important to recognize the gross morphologic characteristics of this rare tumor on MR. The MR pattern of a cystic lesion with enhancing mural nodule is characteristic of PXA, but not diagnostic, and other lower grade gliomas such as ganglioglioma and pilocytic astrocytoma need to be considered. The MR and CT appearance of PXA can provide critical information for the pathologist, especially when only a small amount of tissue is obtained for histologic evaluation.

Adult↗

PubMed2002

Atypical pleomorphic extraosseous ewing tumor/peripheral primitive neuroectodermal tumor with unusual phenotypic/genotypic profile.

A pleomorphic undifferentiated tumor primarily located in the retroperitoneum with a phenotype compatible with an extraosseous Ewing tumor/peripheral primitive neuroectodermal tumor (ET/pPNET) pattern and unusual molecular features is described. Immunohistochemically, HBA-71 (CD99/mic2) and several neural markers were intensively expressed together with scattered cells expressing carcinoembryonic antigen (CEA). Short-term culture showed biphasic neuroblastic and epithelioid cell populations, with the latter expressing germ cell markers (CEA, alpha-fetoprotein, and the beta-subunit of chorionic gonadotrophin). Conventional cytogenetics displayed several chromosomic rearrangements, especially a complex translocation t(17,2,22,13) (q21::q11-->q33::q12-->q13::q14). These structural abnormalities were confirmed using fluorescence in situ hybridization analysis. Molecular studies revealed EWS-FEV fusion transcripts (exon 7 of the EWS gene and exon 2 of the FEV gene). In addition, a new p53 mutation not previously reported in ET/pPNET involving exon 5 codon 138: GCC to GAC (Ala/Asp) was detected. In our case, we emphasize the presence of atypical features not only from the phenotypic point of view but also at the genetic level as well as the value of detecting such markers in the differential diagnosis with other abdominal pleomorphic tumors.

Adult↗

PubMed2004

Pleomorphic hyalinizing angiectatic tumor: analysis of 41 cases supporting evolution from a distinctive precursor lesion.

The pleomorphic hyalinizing angiectatic tumor (PHAT) is a rare, low-grade neoplasm that features atypical stromal cells containing hemosiderin, partially thrombosed ectatic vessels with circumferential hyalinization, and a variable inflammatory infiltrate. Over the years, we have occasionally observed a monomorphic partially myxoid spindle cell component (provisionally termed "early PHAT") co-existing with classic PHAT. In some instances, this monomorphic lesion occurs by itself, suggesting an early stage in the evolution of PHAT. To explore this hypothesis and to better define the long-term behavior of PHAT, we have reviewed our experience with these lesions. Forty-one cases were identified from consultation files. They occurred chiefly in adults (median 51 years, range 10-79 years) of either sex (23 female, 18 male), ranged from 0.3 to 19.7 cm (median 5.6 cm), and involved the subcutis of the ankle/foot (N = 15), leg (N = 10), thigh (N = 6), and other sites. Thirteen tumors had been present for more than 1 year prior to biopsy. Fifteen tumors consisted entirely of typical PHAT. Twelve cases conformed to "early PHAT," lacked fully developed features of PHAT, and showed instead short fascicles of hemosiderin-stippled spindled cells that infiltrated fat and surrounded congeries of small, damaged vessels. With close scrutiny, all contained rare pleomorphic cells with intranuclear pseudo-inclusions, as seen in typical PHAT. Fourteen cases contained both classic and early PHAT, in variable proportions. Follow-up was available in 18 patients (mean 84 months, median 52 months; range 13-420 months). Six of 18 patients developed recurrences, 1 with classic PHAT, 1 with mixed early-classic PHAT, and 4 with early PHAT. Following resection, 16 are disease free and 2 have persistent disease. None has developed metastasis. Based on the histologic overlap between early and classic PHAT, the presence of early PHAT at the periphery of classic PHAT, and the admixture of both patterns within the same tumor, we conclude that early PHAT represents a precursor lesion for PHAT. It appears essentially identical to the lesion termed "hemosiderotic fibrohistiocytic lipomatous lesion," supporting the notion that the latter is a neoplastic rather than a reactive lesion. PHAT should be considered mesenchymal tumors of intermediate malignancy, given their high rate of (sometimes aggressive) local recurrence.

Adolescent↗

PubMed2006

Pleomorphic hyalinizing angiectatic tumor of soft parts: case report and literature review.

Pleomorphic hyalinizing angiectatic tumor (PHAT) of soft parts is a rare soft tissue neoplasm. Few cases have been reported in the literature thus far. PHAT is a spindle cell neoplasm with a prominent vascular component which displays some features of both neurilemoma and malignant fibrous histiocytoma. Lesions typically occur on the lower extremities of adults, however, lesions in other anatomic locations have been described. In this paper, we report a 60 years old female with PHAT of the right foot and review the current literature. El-Tal A-E-K, Mehregan D. Pleomorphic hyalinizing angiectatic tumor of soft parts: case report and literature review.

Diagnosis, Differential↗

PubMed2004

Pleomorphic hyalinizing angiectatic tumor of soft parts: report of a case and review of the literature.

We present the case of a 69-year-old man with a subcutaneous pleomorphic hyalinizing angiectatic tumor of soft parts on the back. In addition to its rare localization, it showed unique clinical features of an exceptionally long history. Histological characteristics of this tumor showed thin-walled angiectatic blood vessels lined with a thick eosinophilic and hyalinotic amorphous material. Tumor cells are composed of pleomorphic cells. It was surgically removed, and there was no recurrence by 11 months postoperatively.

Aged↗