[Recent entities in soft tissue tumor pathology--part 1].
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Angiomyoma↗
Biomedical subjects
L Guillou
Publications and source records attributed to L Guillou.
[An unusual tumor of the spermatic cord].
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Adult↗
Telomerase activity and human telomerase reverse transcriptase mRNA expression in soft tissue tumors: correlation with grade, histology, and proliferative activity.
Telomerase activity (TA) is detected in most human cancers but, with few exceptions, not in normal somatic cells. Little is known about TA in soft tissue tumors. We have examined a series of benign and malignant soft tissue tumors for TA using the telomerase repeat amplification protocol assay. Analysis of the expression of the human telomerase reverse transcriptase was also carried out using RT-PCR. TA was undetectable in benign lesions (15 of 15) and low-grade sarcomas (6 of 6) and was detectable in 50% (19 of 38) of intermediate-/high-grade sarcomas. Although the presence of TA in soft tissue tumors is synonymous with malignancy, it is neither a reliable method in making the distinction between reactive/benign and malignant (especially low-grade) lesions nor a reliable marker of tumor aggressiveness. Leiomyosarcomas and storiform/pleomorphic malignant fibrous histiocytomas rarely showed TA, irrespective of their grade. A strong correlation between human telomerase reverse transcriptase mRNA expression and TA was observed, supporting the close relationship between both parameters. No significant relationship was observed between proliferative activity (as assessed by MIB-1 immunolabeling) and TA. We verified that the absence of telomerase expression was not due to the presence of telomerase inhibitors and therefore alternative mechanism(s) for cell immortalization, yet to be determined, seem to be involved in the development and/or maintenance of some soft tissue sarcomas.
Gene Expression Regulation, Neoplastic↗
Fas and Fas ligand expression in tumor cells and in vascular smooth-muscle cells of colonic and renal carcinomas.
CD95/APO-1 ligand (FasL) is implicated in the maintenance of immune privileged sites by inducing apoptosis of activated infiltrating T lymphocytes. Therefore, progressive tumors might express high levels of FasL and develop as immune privileged sites. In this study, we investigated the expression of FasL and CD95/APO-1 (Fas, the FasL-receptor) in vitro in rat adenocarcinoma cell lines and the localization in situ in normal human kidney and colon and in their adenocarcinomas. The rat cell line PROb (a progressive tumor in vivo) expressed a higher level of FasL than the sister cell line REGb (a regressive tumor in vivo), as detected by flow cytometry. The 2 cell lines expressed the same level of Fas, but were resistant to FasL-induced apoptosis. In human tissue, both kidney and colon extracts expressed FasL by Western blot. Further investigations, using immunohistochemical staining of paraffin sections, showed that normal colon mucosa expressed Fas and FasL in crypt epithelial cells in the subnuclear compartment. Normal kidney showed Fas and FasL labeling mostly restricted to epithelial cells of proximal tubules and Henlé's loop, showing that this expression is not uniform throughout the organ. Smooth-muscle cells of muscularis propria and blood vessels in and around the tumors were also intensely but more uniformly labeled. In colon-cancer cells, FasL expression remained strong, whereas Fas expression was significantly reduced. A similar reduction in Fas expression was noted in renal-cancer cells. Tumor-infiltrating immune cells of the macrophage lineage do not express FasL. Our results show that smooth-muscle cells of muscularis propria and blood vessels are able to express FasL and to a slight extent Fas. In normal epithelial cells of colon and kidney, Fas and FasL are often co-expressed. The reduced expression of Fas in corresponding cancer cells in combination with the ability to express FasL might facilitate immune escape.
Adenocarcinoma↗
Chromosomal abnormalities in renal cell neoplasms associated with acquired renal cystic disease. A series studied by comparative genomic hybridization and fluorescence in situ hybridization.
Sporadic renal cell carcinomas (RCCs) display different chromosomal abnormalities according to their morphology; gains of chromosomes 7 and 17 and loss of Y are commonly observed in papillary lesions, whereas loss of 3p sequences and multiple losses of specific chromosomes are found in non-papillary and chromophobe cell carcinomas, respectively. Acquired renal cystic disease (ARCD) is associated with an increased incidence of renal cell tumours, especially papillary lesions. The aim of this study was to examine a series of ARCD-related tumours for chromosomal abnormalities and to compare the findings with those abnormalities commonly observed in sporadic RCCs. Nine tumours from four patients with ARCD were examined using comparative genomic hybridization (CGH) and interphase cytogenetics. Gain of chromosomes 7 and 17 was observed in all four papillary lesions and loss of Y in three. In addition, gain of chromosome 16 was observed in three papillary tumours. Three chromophobe RCCs originating from the same kidney showed different genomic profiles; two had no abnormalities, whereas one showed loss of chromosome 17p. Two non-papillary RCCs failed to show chromosome 3p alterations. In conclusion, renal cell tumours developing in ARCD may show chromosomal abnormalities both similar to and different from those seen in sporadic tumours.
Adult↗
Symbiomonas scintillans gen. et sp. nov. and Picophagus flagellatus gen. et sp. nov. (Heterokonta): two new heterotrophic flagellates of picoplanktonic size.
Two new oceanic free-living heterotrophic Heterokonta species with picoplanktonic size (< 2 microm) are described. Symbiomonas scintillans Guillou et Chrétiennot-Dinet gen. et sp. nov. was isolated from samples collected both in the equatorial Pacific Ocean and the Mediterranean Sea. This new species possesses ultrastructural features of the bicosoecids, such as the absence of a helix in the flagellar transitional region (found in Cafeteria roenbergensis and in a few bicosoecids), and a flagellar root system very similar to that of C. roenbergensis, Acronema sippewissettensis, and Bicosoeca maris. This new species is characterized by a single flagellum with mastigonemes, the presence of endosymbiotic bacteria located close to the nucleus, the absence of a lorica and a R3 root composed of a 6+3+x microtubular structure. Phylogenetical analyses of nuclear-encoded SSU rDNA gene sequences indicate that this species is close to the bicosoecids C. roenbergensis and Siluania monomastiga. Picophagus flagellatus Guillou et Chrétiennot-Dinet gen. et sp. nov. was collected in the equatorial Pacific Ocean. Cells are naked and possess two flagella. This species is characterized by the lack of a transitional helix and lateral filaments on the flagellar tubular hairs, the absence of siliceous scales, two unequal flagella, R1 + R3 roots, and the absence of a rhizoplast. SSU rDNA analyses place this strain at the base of the Chrysophyceae/Synurophyceae lineages.
Animals↗
Photodetection of early human bladder cancer based on the fluorescence of 5-aminolaevulinic acid hexylester-induced protoporphyrin IX: a pilot study.
Exogenous administration of 5-aminolaevulinic acid (ALA) is becoming widely used to enhance the endogenous synthesis of protoporphyrin IX (PpIX) in photodynamic therapy (PDT) and fluorescence photodetection (PD). Recently, results have shown that the chemical modification of ALA into its more lipophilic esters circumvents limitations of ALA-induced PpIX like shallow penetration depth into deep tissue layers and inhomogeneous biodistribution and enhances the total PpIX formation. The present clinical pilot study assesses the feasibility and the advantages of a topical ALA ester-based fluorescence photodetection in the human bladder. In this preliminary study 5-aminolaevulinic acid hexylester (h-ALA) solutions, containing concentrations ranging from 4 to 16 mM, were applied intravesically to 25 patients. Effects of time and drug dose on the resulting PpIX fluorescence level were determined in vivo with an optical fibre-based spectrofluorometer. Neither local nor systemic side-effects were observed for the applied conditions. All conditions used yielded a preferential PpIX accumulation in the neoplastic tissue. Our clinical investigations indicate that with h-ALA a twofold increase of PpIX fluorescence intensity can be observed using 20-fold lower concentrations as compared to ALA.
Aged↗
Hobnail hemangioma: a pseudomalignant vascular lesion with a reappraisal of targetoid hemosiderotic hemangioma.
The clinicopathologic features of 15 cutanous hemangiomas having a distinctive and frequently pseudomalignant morphologic appearance are presented. There were 5 male and 9 female patients, whose ages at diagnosis ranged from 11 to 58 years (median 30.5). An angiomatous/pigmented, nontargetoid, flat, or exophytic lesion of variable duration was the main presenting sign. The tumor sizes ranged from 0.4 cm to 2 cm (median 1 cm). The locations included the lower limb, particularly the thigh (8); the trunk, including the shoulder area (4); the head (1); the gingiva (1); and the tongue (1). One patient had two lesions; none had a concomitant vascular anomaly or was suspected to have HIV infection. Treatment consisted of excisional biopsy in all cases. Follow-up information on 10 patients (range 4-66 months; median 13 months) showed no recurrence. On microscopic examination, the lesion showed a biphasic pattern characterized by the presence of well-formed, dilated, vascular channels in superficial dermis and a collagen-dissecting, pseudoangiosarcomatous pattern as the lesion infiltrated deeper into the dermis. The lining endothelium consistently showed distinctive hobnail cytomorphology; although there were endoluminal stromal papillae, there was no endothelial multilayering or tufting. Cytologic atypia was minimal or absent, and there were no mitoses. In 3 cases, the morphologic features were reminiscent of retiform hemangioendothelioma. Immunohistochemistry performed in 8 cases showed variable reactivity of endothelial cells with CD31, CD34, Factor VIII-related antigen, and Ulex europaeus agglutinin-1 in all cases; smooth muscle actin-positive pericytes were observed focally around some of the abnormal vascular spaces. The above-described hemangiomatous lesions share many features with so-called targetoid hemosiderotic hemangioma (a clinically descriptive term), but show a variable, often minimal, amount of hemosiderin deposition. The histologically descriptive term hobnail hemangioma is proposed to designate these lesions. Hobnail hemangioma should be distinguished from well-differentiated angiosarcoma, patch-stage Kaposi's sarcoma, and retiform hemangioendothelioma, with which it may be confused.
Adolescent↗
Diversity and abundance of Bolidophyceae (Heterokonta) in two oceanic regions.
The diversity and abundance of the Bolidophyceae (Heterokonta), a newly described picoplanktonic algal class which is a sister group to the diatoms, was assessed in the equatorial Pacific Ocean and in the Mediterranean Sea by culture isolation, molecular biology techniques, and pigment analyses. Eight strains of Bolidophyceae were isolated in culture from different mesotrophic and oligotrophic areas. The corresponding small subunit (SSU) rRNA gene sequences allowed us to design two probes specific for the Bolidophyceae. These probes have been used in natural samples (i) to selectively amplify and detect Bolidophyceae sequences and (ii) to quantify the relative abundance of Bolidophyceae within the picoeukaryote community. Sequences available to date indicate that the class Bolidophyceae comprises at least three different clades, two corresponding to the previously described species Bolidomonas pacifica and Bolidomonas mediterranea and the third one corresponding to a subspecies of B. pacifica. Amplification of the SSU rRNA gene from natural samples with universal primers and hybridization using a Bolidomonas-specific probe followed by a eukaryote-specific probe allowed us to estimate the contribution of the Bolidophyceae to the eukaryotic DNA in both Pacific and Mediterranean waters to be lower than 1%. Similarly, high-performance liquid chromatography analyses of fucoxanthin, the major carotenoid present in Bolidophyceae, indicated that less than 4% of the total chlorophyll a in the picoplanktonic fraction in the equatorial Pacific was due to Bolidophyceae. Consequently, although strains of Bolidophyceae have been isolated from samples collected at several stations, this new class seems to have been a minor component of the natural picoeukaryotic populations in the ecosystems investigated, at least during the periods sampled.
Animals↗
Renal metastasis from prostatic adenocarcinoma: a potential diagnostic pitfall.
We report a case of renal metastases from prostate cancer to show that the possibility of tumor metastasis, although rare, should always be considered in the differential diagnosis of renal mass.
Adenocarcinoma↗
Food-dependent Cushing's syndrome: possible involvement of leptin in cortisol hypersecretion.
Stimulation ofcortisol secretion by food intake has been implicated in the pathogenesis of some cases of ACTH-independent Cushing's syndrome, via an aberrant response of the adrenal glands to gastric inhibitory polypeptide (GIP). We report here a novel case of food-dependent Cushing's syndrome in a patient with bilateral macronodular adrenal hyperplasia. In this patient we were able to confirm a paradoxical stimulation of cortisol secretion by GIP in vivo as well as in vitro on dispersed tumor adrenal cells obtained at surgery. In addition to GIP, in vitro stimulation of these cultured tumor adrenal cells with leptin, the secreted product of the adipocyte, induced cortisol secretion. By comparison, no such stimulation was observed in vitro in adrenal cells obtained from another patient with bilateral macronodular adrenal hyperplasia and Cushing's syndrome that did not depend on food intake, in tumor cells obtained from a solitary cortisol-secreting adrenal adenoma, and in normal human adrenocortical cells. These results demonstrate that as in previously described cases of food-dependent Cushing's syndrome, GIP stimulated cortisol secretion from the adrenals of the patient reported here. Therefore, they indicate that such a paradoxical response probably represents the hallmark of this rare condition. In addition, they suggest that leptin, which normally inhibits stimulated cortisol secretion in humans, participated in cortisol hypersecretion in this case. Further studies in other cases of food-dependent Cushing's syndrome, however, will be necessary to better ascertain the pathophysiological significance of this finding.
Adrenal Glands↗
[New information in the classification of urothelial tumors of the bladder].
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Carcinoma, Transitional Cell↗
(E)-2'-deoxy-2'-(fluoromethylene) cytidine potentiates radioresponse of two human solid tumor xenografts.
Antitumor and radiosensitizing effects of (E)-2'-deoxy-2'-(fluoromethylene) cytidine (FMdC), a novel inhibitor of ribonucleotide reductase, were evaluated on nude mice bearing s.c. human C33-A cervix cancer and U-87 MG glioblastoma xenografts. FMdC given once daily has a dose-dependent antitumor effect. The maximum tolerated dose in the mice was reached with 10 daily i.p. administrations of 10 mg/kg over 12 days. In the case of radiotherapy (RT) alone (10 fractions over 12 days), the radiation dose required to produce local tumor control in 50% of the treated C33-A xenografts was 51.0 Gy. When combined with FMdC, the radiation dose required to produce local tumor control was reduced to 41.4 and 38.2 Gy, at respective doses of 5 and 10 mg/kg given i.p. 1 h before each irradiation. The corresponding enhancement ratios (ERs) were 1.2 and 1.3, respectively. In U-87 MG xenografts, when 5-20 mg/kg FMdC combined with 30 or 40 Gy of RT, the combination treatment produced a significantly increased growth delay as compared with RT alone (P < or =0.002). The ERs of 5, 10, and 20 mg/kg FMdC at a dose of 30 Gy were 2.0, 1.4, and 1.8, respectively. At the 40-Gy level, ERs of 10 and 20 mg/kg FMdC were 1.4 and 1.7. When FMdC was combined with 50 Gy of RT, an increased long-term remission rate of 80-88.9% was observed, as compared with 25% for RT alone (P <0.05). FMdC produced moderate myelosuppression in the mice bearing cervix cancer, whereas leukocytosis occurred in the mice bearing glioblastoma at a low dose. Slightly increased skin toxicity (only with U-87 MG tumor) was observed, as compared with RT alone. In conclusion, FMdC is a potent cytotoxic agent and able to modify the radiation response of C33-A and U-87 MG xenografts.
Animals↗
Primary heterologous carcinosarcoma (metaplastic carcinoma) of the urinary bladder: a clinicopathologic, immunohistochemical, and ultrastructural analysis of eight cases and a review of the literature.
BACKGROUND: Heterologous carcinosarcomas of the urinary bladder are rare neoplasms, the histogenesis of which is still disputed. METHODS: The clinicopathologic, immunohistochemical, and ultrastructural features of eight cases were analyzed. RESULTS: The patients, 5 males and 3 females, had a median age of 70 years. Gross hematuria, dysuria, and urinary tract infections were the main presenting symptoms. Tumors were solitary in all cases and located in the right wall in six cases. Tumor size ranged from 2 to 12 cm (median, 5 cm). Four patients died of disease 2, 6, 17, and 42 months postoperatively, respectively. Microscopically, the tumors consisted mostly of a varied mixture of high grade transitional cell carcinoma with chondrosarcoma, osteosarcoma, rhabdomyosarcoma, and undifferentiated spindle cell (leiomyosarcoma-like) components with occasional transitional features between one component and another. All tumors but one invaded the muscularis propria or the perivesical fatty tissue. Immunohistochemically, keratin expression was observed focally in the sarcoma component as well as the carcinoma component. Reactivity for vimentin, desmin, muscle specific actin, and S-100 protein was observed in poorly differentiated areas in addition to the expected positivity of each histologic subtype of sarcoma. Ultrastructurally, one tumor showed evidence of both epithelial and chondrosarcomatous differentiation, whereas three contained rhabdomyosarcomatous elements. CONCLUSIONS: On the basis of the current series and a review of 55 reports from the literature, primary heterologous carcinosarcoma of the urinary bladder proved to be a highly malignant type of neoplasm occurring predominantly in elderly males that was most often in an advanced stage at presentation and rapidly became lethal. Histogenetically, some heterologous carcinosarcomas should be regarded as a variant of sarcomatoid carcinoma (metaplastic carcinoma) that shows prominent heterologous differentiation.
Aged↗
Pathologic fracture of the femur neck as first manifestation of a minute columnar cell carcinoma of the thyroid gland.
This case report concerns a 64 year-old woman who presented a pathologic fracture of the femur neck. Histologic examination of the performed bone biopsy disclosed the presence of a carcinomatous metastasis with unusual microscopic features. The site of the primary tumor could be unequivocally determined as being the thyroid gland, as immunostaining of the tumor cells showed positivity with anti-thyroglobulin. The thyroidectomy specimen weighed 149 g, was nodular and partially calcified. Exhaustive microscopic examination finally revealed the presence of a minute columnar cell carcinoma, 0.6 cm in diameter, with obvious vascular invasion. This case illustrates well 1) the usefulness of immunostaining with anti-thyroglobulin in cases of bone metastasis with unusual microscopic features and unknown primary, as well as 2) the aggressiveness of this rare type of carcinoma of the thyroid.
Carcinoma, Papillary↗
Skeletal muscle regeneration mimicking rhabdomyosarcoma: a potential diagnostic pitfall.
AIMS: We report three cases of skeletal muscle regeneration, of which two mimicked a small round cell tumour, especially a rhabdomyosarcoma. METHODS AND RESULTS: One case presented as an intramuscular mass, located in the right quadriceps of a 12-year-old male; the second patient was a 25-year-old football player who complained of painful left peroneus muscles; the third patient was a 22-year-old male who underwent an amputation of the right thigh 5 days after right leg amputation due to limb crush. Histologically, muscle biopsy specimens showed a proliferation of small round cells, either infiltrating the striated muscle in a diffuse manner or growing within and around necrotic myofibres. Immunohistochemically and ultrastructurally, the cellular population was composed of two types of cells: phagocytic cells the nuclei of which occasionally showed a wreathlike arrangement around necrotic myofibres resulting in structures resembling Langhans-type multinucleated giant cells, and proliferating satellite cells showing enlarged nuclei, prominent nucleoli, mitotic figures, myogenic differentiation and fusion features in order to form regenerating myotubes. CONCLUSIONS: Muscle regeneration is a benign process that may occasionally mimic a small round cell proliferation resembling a lymphoma or an alveolar rhabdomyosarcoma with which it should not be confused.
Adult↗
Dedifferentiated liposarcoma: a report of nine cases with a peculiar neurallike whorling pattern associated with metaplastic bone formation.
Nine cases of dedifferentiated liposarcoma with both a peculiar neurallike or meningeallike whorling pattern and metaplastic bone formation are reported. The tumors predominated in the retroperitoneum of elderly adults. All nine tumors were resected, and five of seven that were followed-up recurred locally, but none metastasized after a follow-up of 2 to 7 years. Grossly, most of the tumors were huge masses, ranging from 2.5 cm to 60 cm. Histologically, the tumors revealed, in addition to areas of well-differentiated liposarcoma, discrete nodules consisting of hypercellular, spindled to ovoid cellular proliferation arranged in tight, concentric whorls resembling neural tumors or meningiomas. Metaplastic, heterotopic ossification was present in seven of nine tumors and consisted of variable amounts of osteoblast-rimmed bone trabeculae situated at the periphery of the whorled areas or intimately mixed with the whorled cellular component. Immunohistochemical studies were inconclusive in determining the nature of the dedifferentiated, whorled element. Ultrastructural evaluation of one tumor disclosed neoplastic cells featuring thin, interdigitating cytoplasmic processes connected by desmosomes, similar to those described in follicular dendritic cell neoplasms. Although suggested by the light and electron microscopic features, the follicular dendritic cell differentiation of the dedifferentiated component could not be confirmed on immunohistochemical grounds, and the histogenesis of the intriguing neurallike or meningiomalike component in these dedifferentiated liposarcomas is unknown.
Adult↗