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B Carlén

Publications and source records attributed to B Carlén.

At least 19 recordsLinked to original sources
PubMed2001

Distinct cytologic features of spindle cell lipoma. A cytologic-histologic study with clinical, radiologic, electron microscopic, and cytogenetic correlations.

BACKGROUND: Spindle cell lipoma (SCL) is a relatively uncommon, benign tumor that usually presents in the subcutaneous fat of adult men. Although some studies have addressed the histologic findings of SCL, only a few descriptions of aspiration cytology findings have been published. The cytologic features are poorly defined, and aspirates from SCL may cause diagnostic problems, because SCL shares some features with other fatty/spindle cell or myxoid lesions, benign as well as malignant. METHODS: Twelve patients underwent fine-needle aspiration (FNA) cytology as the primary diagnostic modality before surgery. FNA findings were evaluated and correlated with histologic features. In addition, radiologic, electron microscopic, and cytogenetic findings were analyzed. The objective of this study was to determine cytologic criteria of SCL by reviewing cytologic specimens in 12 patients with SCL who underwent FNA cytology. RESULTS: All of the tumors arose in adults, and 10 tumors developed in the subcutaneous tissue of the neck, back, or shoulder girdle. Two patients presented with tumors in atypical locations; one in the tongue and one in the cheek. Cytologically, all 12 tumors were characterized by a mixture of mature adipocytes, uniform spindle cells, and collagen bundles and/or fibers in varying proportions. The presence of a myxoid matrix and of mast cells was less specific and occurred in six aspirates. CONCLUSIONS: SCL has a characteristic cytologic appearance that, together with clinical data, helps to exclude low-grade liposarcoma as well as other spindle cell and myxoid lesions.

Adult↗
PubMed2001

Cytologic findings in granular cell tumors, with emphasis on the diagnosis of malignant granular cell tumor by fine-needle aspiration biopsy.

BACKGROUND: Granular cell tumors (GCTs) are uncommon tumors of putative schwannian derivation that are rarely malignant. Although recent studies have addressed a histologic correlation with malignant behavior, similar studies have not been done on cytologic material. METHODS: The authors evaluated 3 malignant GCTs and 17 benign GCTs (comprising 17 fine-needle aspiration biopsy samples and 3 samples from direct scrapes) for the following cytologic features: hyperchromasia; coarse chromatin; nuclear-to-cytoplasmic (N/C) ratio; nuclear pleomorphism; and vesicular nuclei with enlarged nucleoli, mitoses, necrosis, and spindle cell morphology. RESULTS: Hyperchromasia, coarse chromatin, increased N/C ratio, nuclear pleomorphism, and vesicular nuclei with enlarged nucleoli and spindle cell morphology were associated the most closely with malignancy when they were present throughout the cytologic sample. All were diffusely present in three of three malignant tumors, except vesicular nuclei and spindle cell morphology, which were present diffusely in two tumors and focally in one tumor. By contrast, although one to five of these features were present focally in 8 of 17 benign GCTs, none was present diffusely in any benign GCTs, with one exception, which had a combination of focal nuclear pleomorphism and hyperchromasia together with diffuse vesicular nuclei, large nucleoli, and coarse chromatin. The N/C ratio in this tumor was not increased, and there were no spindle cells or mitoses. Mitoses were present in 2 of 3 malignant GCTs and absent from all 17 benign GCTs. Necrosis was not seen in any tumors. CONCLUSIONS: Malignant GCTs have characteristic cytologic features that differ from those of benign GCTs. However, morphologic heterogeneity precludes definitive classification of some tumors by cytologic features alone.

Adolescent↗
PubMed2000

Modes of adherence of Helicobacter pylori to gastric surface epithelium in gastroduodenal disease: a possible sequence of events leading to internalisation.

We have investigated various modes of adherence of Helicobacter pylori to the human gastric epithelium, using transmission electron microscopy, in biopsies from nine patients with peptic ulcer disease and from four patients with chronic active gastritis. H. pylori was demonstrated in abundance in all cases within the surface mucous layer. In all ulcer- and in one out of four gastritis patients H. pylori was shown in close proximity to the gastric epithelium, with concurrent alterations in the configuration of microvilli and the apical cytoplasmic region of gastric cells. Previously described modes of H. pylori adherence were confirmed, such as loose attachment with fibrillar-like strands, firm attachment with pedestal formation, invasion in the intercellular spaces, and invagination with "cup" formation. Moreover, in many cases a fusion between the bacterial outer layer and gastric cell membranes was evident. In four cases (31%; three with active and one with past ulcer disease) viable H. pylori was found in the cytoplasm of gastric mucous cells. Our results support the hypothesis that the different modes of adherence of H. pylori represent a stepwise, possibly sequential, process which in a significant number of cases leads to internalisation of the organism. The invariable occurrence of adhesion and more frequent internalisation of H. pylori in ulcer patients may suggest a link with the pathogenesis of peptic ulcer disease.

Adult↗
PubMed2000

Morphologic conversion of Helicobacter pylori from spiral to coccoid form. Scanning (SEM) and transmission electron microscopy (TEM) suggest viability.

Helicobacter pylori is a pathogen associated with type B gastritis, peptic ulcer disease, gastric atrophy, and stomach cancer. H. pylori exists in two morphological forms, spirals and coccoids. The latter has been described as viable but non-cultivable. The role of the coccoid form in the pathogenesis of gastric disease is disputed. Some authors consider the coccoid form to be a degenerative or dead form of H. pylori, while others consider it a resting but still metabolically active form. This study reports the conversion from spiral to coccoid form ultrastructurally. Dense material is accumulated in the periplasmic space, the spiral bacteria bend and the outer membrane is separated from the inner cell wall layer. Remodeling of inner structures takes place, ending in the coccoid form of the bacteria with preserved light polyphosphate areas. Reduction of surface takes place by production of surface membrane vesicles, which later are squeezed off. The finding of preserved subcellular structures and intact double membranes in combination with degenerative forms suggests that some of the coccoids are viable. Scanning electron microscopy (SEM) demonstrates coccoid form of bacteria with slightly ruffled surfaces but no spiral forms.

Culture Media↗
PubMed1999

Cloacogenic adenocarcinoma of the vulva.

Primary adenocarcinoma of the vulva is rare, and cloagocenic adenocarcinoma of the vulva is extremely rare. Here we report a vulvar tumor characterized by columnar cells with prominent brush border and the presence of goblet cells and endocrine cells, presenting the tubulovillous pattern and mucin histochemistry of enteric adenocarcinoma. Electron microscopy verified a colon-like pattern. We suggest that cloacogenic carcinoma of the vulva arises from embryonic tissue, normally present in the vulvar introital area. In our case, a wide local excision was sufficient for radical cure.

Adenocarcinoma↗
PubMed1999

Unique cytological features and chromosome aberrations in chondroid lipoma: a case report based on fine-needle aspiration cytology, histopathology, electron microscopy, chromosome banding, and molecular cytogenetics.

Chondroid lipoma is a rare, benign tumor that may mimic soft-tissue sarcoma clinically. Its histopathologic features may resemble hibernoma, myxoid liposarcoma, myxoid chondrosarcoma, and other lipomatous or chondroid neoplasms. In this study, a chondroid lipoma was analyzed by fine-needle aspiration cytology, histopathology, electron microscopy, chromosome banding, and metaphase fluorescence in situ hybridization. The results demonstrate that chondroid lipoma exhibits a characteristic pattern by fine-needle aspiration cytology, including a mixture of benign adipose tissue with lipoblastlike cells, and chondroblastlike cells with a fibrochondroid matrix. Cytogenetically, a three-way rearrangement between chromosomes 1, 2, and 5 was found, together with an 11;16 translocation with a breakpoint in 11q13, approximately 1 Mb proximal to the MEN1 region shown to be rearranged frequently in hibernoma. The presence of a karyotype of low complexity, but without any of the genetic aberrations characteristic for other types of soft-tissue tumors, indicate that chondroid lipoma develops along a unique pathogenetic pathway.

Adult↗
PubMed1997

Infection of BALB/c A mice by spiral and coccoid forms of Helicobacter pylori.

Helicobacter pylori exists in two different morphological forms, spiral and coccoid. This study demonstrated that both forms can infect BALB/c A mice. The animals were inoculated orally three times at 2-day intervals with 10(8) cfu of both spiral and coccoid forms of strain CCUG 17874 (NCTC 11637), strain 25 and strain 553/93. Infection was followed over a 30-week period by histological scoring of the grade of inflammation in gastric biopsies. At each time point sera were collected for analysis in ELISA and immunoblot analysis. Both spiral and coccoid forms of all H. pylori strains gave significantly higher inflammation scores than a control group of animals 1 week after inoculation. The histological evidence persisted throughout the entire 30 weeks. The inflammation was most severe in the pylorus and duodenum. Infection with strain 553/93 displayed the most severe gastritis. The spiral form of strain CCUG 17874 gave an immune response after only 4 weeks, whereas its coccoid form as well as strains 25 and 553/93 (spiral and coccoid forms) gave a significant increase in antibody response in ELISA and immunoblot after 16 weeks. It is concluded that both spiral and coccoid forms of H. pylori can cause acute gastritis in BALB/c A mice.

Animals↗
PubMed1996

Fine needle aspiration (FNA) of synovial sarcoma--a comparative histological-cytological study of 15 cases, including immunohistochemical, electron microscopic and cytogenetic examination and DNA-ploidy analysis.

A retrospective study of 25 FNAs (11 aspirates from primary tumours and 14 from recurrencies and metastases) from 15 synovial sarcomas was performed. The cytological findings were correlated with the histopathology and the value of immunohistochemical and electron microscopic examination as well as DNA-ploidy and cytogenetic analysis for diagnosis were assessed. A reproducible cellular pattern with a reliable diagnosis of spindle cell sarcoma was possible provided that the aspirates were cell rich. However, a true biphasic pattern indicative of synovial sarcoma was only seen in one of the 25 specimens. Electron microscopic examination of the aspirates was a valuable adjunctive diagnostic method, whereas immunocytochemistry and DNA-ploidy analysis were not. Immunohistochemical, electron microscopic and cytogenetic analysis were all valuable ancillary methods when performed on surgical specimens. Malignant haemangiopericytoma and fibrosarcoma were the most important differential diagnoses in the FNA specimens.

Adult↗
PubMed1996

Ileal conduit stenosis--an enigma.

Ileal conduit stenosis was diagnosed in 12 patients in the period 1981-1994. The time between urinary diversion and this diagnosis was 7-30 (mean 14) years. The clinical picture, i.e. colicky flank pain and/or fever, was produced by upper urinary tract obstruction. Intravenous urography, loopography and looposcopy were used in diagnosis. Treatment consisted of removal of the conduit and replacement by a new ileal loop or a continent reservoir, or partial resection with or without ureteric reimplantation. Light microscopy of the removed conduits showed severe, sometimes transmural inflammation with submucosal fibrosis. Transmission electron microscopy (TEM) demonstrated reduced height of microvilli, presence of glycocalyceal bodies and an increased number of lysosomes. Other subcellular structures were intact. The pathogenesis of the stenosis is obscure. Microvascular insufficiency, infection in conjunction with exposure to urine, reaction to some noxious agent in the urine or immunologic causation have been proposed. This late stenosis seems to arise only when ileum is used as conduit. Its insidious course calls for lifelong observation of the upper urinary tracts in these patients.

Aged↗
PubMed1996

Diagnostic value of electron microscopy in rare malignant musculoskeletal tumors. Experience from an orthopedic tumor center.

Rare musculoskeletal tumors can be difficult to diagnose by light microscopy or immunohistochemistry. Electron microscopy can be of diagnostic assistance especially if histotype specific ultrastructural features exist. In particular, electron microscopy for uncommon sarcomas such as alveolar soft part sarcoma, parachordoma, atypical Ewing's sarcoma and epithelioid sarcoma may be the diagnostic modality of choice.

Adult↗
PubMed1996

Morphologic changes in intestinal mucosa with urinary contact--effects of urine or disuse?

PURPOSE: To evaluate the morphological changes induced in bypassed ileal and colonic segments and the influence of the urine on the mucosal histology. MATERIALS AND METHODS: In a rat model, an isolated ileocolonic segment was used for construction of an ileocolocystoplasty or an exteriorized blind loop. Sham-operated animals were used for control. RESULTS: In ileal mucosa, villi and microvilli were better preserved when exposed to urine than when deprived of contact with luminal content. Numerical reduction of microvilli was found in colonic mucosa deprived of luminal content. In colonic mucosa exposed to urine some areas were denuded of microvilli and showed blebs. Findings of intact tight junctions in all specimens implied that an important morphological requirement of maintained epithelial barrier function is present in mucosa deprived of normal luminal stimulation and also after contact with urine. The intracellular ultrastructural changes in both colon and ileum were similar in the 2 groups. However, there were more solitary ribosomes lying free in the mucosa exposed to urine, indicating depressed or arrested protein synthesis. CONCLUSIONS: Mucosa in contact with urine seems to maintain surface characteristics better than mucosa deprived of luminal stimulation, indicating that factors present in the urine may be important for the epithelial cell physiology. Certain intracellular changes were found more often in mucosa exposed to urine, but there were no major differences. The changes noticed may indicate enterocyte adaptation to a new physiologic environment.

Animals↗
PubMed1995

Trisomy 20 is a primary chromosome aberration in desmoid tumors.

Cytogenetic analysis revealed trisomy 20 in 4 desmoid tumors: in 2 cases as the sole aberration, in 1 together with +X, -Y and -13 and in 1 with +8 and a supernumerary marker chromosome. Our findings indicate that gain of chromosome 20 is an early event in the development of a large subset of desmoid tumors and that it is as frequent as +8, the only consistent chromosomal change previously reported in this tumor type. The non-random occurrence of trisomies 8 and 20 in desmoid tumors indicates shared pathogenetic mechanisms with infantile fibrosarcoma, a fibrous tissue tumor characterized by various combinations of trisomies for chromosomes 8, 11, 17 and 20.

Adult↗
PubMed1995

Fine needle aspiration (FNA) in the diagnosis of soft tissue tumours; a review of 22 years experience.

FNA plays an important role in preoperative diagnosis of soft tissue tumours. A close clinical/morphologic cooperation is essential. FNA should be performed on the most accessible part of the tumour, avoiding penetration of the deep portions of the tumour. Needles 0.7 mm (22 G) are recommended. For deep lesions, needles with a stylet should be used. After the FNA, tattooing of the aspiration channel is recommended, and the channel is surgically removed together with the tumour, if a sarcoma. Material from the FNA can be used for additional examinations, i.e. electron microscopy, immunohistochemistry, DNA ploidy analysis and chromosomal analysis. Those techniques are of great importance in the differential diagnosis, particularly in the paediatric small/round cell tumours. The majority of sarcomas can be defined as low grade or high grade malignant in FNA. For malignancy grading the following parameters are used: cellularity, pleomorphism, chromatin pattern, nucleolar structure, mitotic figures and necroses. Cytodiagnostic details of the most common soft tissue tumours and their differential diagnoses are presented.

Biopsy, Needle↗
PubMed1995

Pigmented villonodular synovitis. Monoclonality and metastasis--a case for neoplastic origin?

We report a 48-year follow-up of a case of recurrent pigmented villonodular synovitis of the knee. Subcutaneous metastasis to the contralateral thigh was an unusual finding. Histology demonstrated fibroblastic and histiocytic proliferation, as well as increased mitotic activity in recurrent lesions. Cytogenetic analyses demonstrated monoclonality and chromosomal abnormalities. Our findings support a neoplastic origin of this lesion.

Aged↗
PubMed1994

Splenic response to silicon drain material following intraperitoneal implantation.

To study the splenic response to intraperitoneal biomaterials, 100% silicon rubber drain fragments were intraperitoneally implanted in the rat. Four days after implantation, specimens of the spleen and implanted rubber fragment were retrieved and subjected to scanning electron microscopy (SEM) and energy dispersive X-ray microanalysis (EDX). In SEM, macrophages with membrane fusion and cytoplasmic spreading were noted on the surfaces of implanted rubber fragments. Specimens of the spleen from animals with implants showed light 3-10-microns structures that were not observed in those without implants. EDX revealed the presence of silicon both in the rubber fragment and in the spleen of the implanted animals. Both light microscopy and transmission electron microscopy showed a large number of particles inside giant cells of the spleen. The present study demonstrated an active transport of rubber fragments containing silicon from the peritoneal cavity to the spleen by adherent macrophages, reflecting a splenic response to intraperitoneal implantation of biomaterials. The modes of silicon rubber degradation and transportation remain to be elucidated.

Animals↗
PubMed1994

Sarcoma of the pulmonary artery: report of four cases with electron microscopic and immunohistochemical examinations, and review of the literature.

Herein we report the clinicopathological features of four cases of pulmonary artery sarcoma that appeared at our institution during a period of 30 years. The patients, 2 males and 2 females, were 50-62 years old. Tumour was found in the pulmonary trunk and right pulmonary artery in all cases, in the pulmonary valve and left pulmonary artery in three of the four cases, and in the right ventricular outflow tract in one case. There was direct extension or metastases to the lungs in two cases, the heart in one case, mediastinum or lymph nodes in two cases and the pleura in one case. Ultrastructural examination in one case revealed cells with features of smooth muscle cells and myofibroblasts. Immunohistochemical examination of three cases gave the following results: vimentin and smooth muscle specific actin was positive in all three cases, desmin in one case and cytokeratin in one case. No positivity was found for Factor VIII. This and other studies indicate that histologically most pulmonary artery sarcomas are leiomyosarcomas or "undifferentiated spindle cell sarcomas". Immunohistochemical and ultrastructural examinations favour an origin from myofibroblasts, probably derived from multipotent (undifferentiated) cells in the wall of the vessel. Most lesions show extensive intrathoracic growth although they rarely metastasize outside the thoracic cavity. They have a poor prognosis although some cases are currently being diagnosed during life.

Cell Membrane↗