PubMed Health⌕ Search

Biomedical subjects

A G Perevoshchikov

Publications and source records attributed to A G Perevoshchikov.

At least 19 recordsLinked to original sources
PubMed2006

[Signet ring cancer of the stomach: clinico-morphological features, postsurgical results and prognosis].

Clinico-morphological features of signet ring cancer of the stomach were evaluated in 372 out of 2,308 gastric cancer patients undergoing gastroectomy or stomach resection. Signet ring tumor pathology occurs mostly in young females and younger patients generally. It features high incidence of early cancers, low frequency of metastatic spreading to lymph nodes (T1-T2), high frequency of immediate involvement of perigastric fatty tissues, peritoneum and ovaries and infrequent spreading to the liver. Post-surgical survival rates among patients with T1-T2 were relatively high, yet declining in cases of extension through the serous membrane of the stomach. D2-lymphdissection failure to improve the end-results of surgical treatment of signet ring cancer might be accounted for by the predominance of peritoneal metastases of this morphological pattern. Histochemical assay of mucines might be contribute additional data on prognosis.

Carcinoma, Signet Ring Cell↗
PubMed2005

Expression of E-cadherin, beta-catenin, and CD-44v6 cell adhesion molecules in primary tumors and metastases of colorectal adenocarcinoma.

Immunohistochemical analysis of the expression of E-cadherin, beta-catenin, and CD-44v6 proteins was carried out for evaluating the metastatic potential of colorectal cancer cells. Specific features of expression, distribution, and interactions of adhesive molecules in primary tumors of the large intestine and their metastases in the liver and lymph nodes were studied. Reduction and complete absence of E-cadherin expression were much more often observed in patients with colorectal cancer with metastases in the liver than in patients without metastases. Cytoplasmic immunoreactivity and nuclear translocation of beta-catenin were increased in more than 80% cases with colorectal adenocarcinoma with metastases. These changes in the expression of E-cadherin and beta-catenin in tumor cells can be regarded as factors of unfavorable prognosis of colorectal cancer. No significant relationship between expression of CD-44v6 protein and metastatic potential of cancer cells was detected.

Adenocarcinoma↗
PubMed2005

[The features of expression of cellular adhesion molecules in primary colorectal cancer and its metastases].

Features of expression, distribution and interaction of E-cadherin, beta-catenin and CD-44v6 were immunologically assayed in samples from primary colorectal tumors (129) and their metastases to the lymph nodes (35) and liver (92). Reduction or total absence of E-cadherin expression was significantly more typical of tumors metastasizing, at different stages, to the liver (64/84, 76%) than in metastasis-free ones (14/45, 31%) (p=0.014). Enhanced cytoplasmic immunoreactivity and beta-catenin nuclear translocation occurred in 80% of disseminated tumors. Such alterations of E-cadherin, beta-catenin expression may be regarded as unfavorable prognosis factors involved in colorectal cancer. No significant correlation between CD-44v6 expression and tumor cell ability to metastasize was recorded.

Adult↗
PubMed2003

Immunohistological study of NM 23 and C-erbB-2 expression in primary tumor and metastases of colorectal adenocarcinoma.

Immunohistochemical study of expression of nm 23 and c-erbB-2 protein markers in primary tumor and metastases of colorectal adenocarcinoma showed that the incidence and expression of both protein markers in primary tumor tissue tended to increase after the appearance of liver metastases. Peculiarities of protein expression in tumor metastases in lymph nodes and liver and the possibility of using these markers as additional prognostic criteria in colorectal cancer are discussed.

Adenocarcinoma↗
PubMed2001

Soluble Fas antigen in the serum of patients with colon cancer.

Serum concentration of soluble Fas antigen (sFas) was measured in 60 normal subjects and 33 patients with colon cancer. The incidence of sFas detection and its serum content were higher in patients with colon cancer compared to normal subjects. No relationships between the incidence and level of sFas and patient's sex, age, duration and stage of the disease were found. Serum content of sFas tended to increase in patients with metastases to regional lymph nodes, liver, and lungs. The role of sFas as a marker predicting clinical course and outcome of colon cancer is discussed.

Adenocarcinoma↗
PubMed1998

[Genetic alterations in the region of the p53 gene on human chromosome 17 in colorectal cancer].

Most colorectal tumors are characterized, among other genetic alterations, by allele loss of the genes located on the short arm of chromosome 17 (17p13.1), including the p53 suppressor gene. In ovarian and mammary-gland tumors, deletions of another candidate tumor-suppressor gene, located in the 17p13.3 chromosome region, were observed. We analyzed allele losses in the loci of the short arm of chromosome 17 (YNZ22, MCT35.1, and the p53 gene) in colorectal-cancer patients from the former Soviet Union. Tumors with cytogenetic alterations in 17p and/or with a detected loss of heterozygosity at the YNZ22 (D17S30) locus were examined for allele losses in the p53 gene using two polymorphic sites. Different methods revealed alterations on 17p in 24 (48%) out of 50 patients with colorectal carcinomas. In all tumors with an allele loss of the YNZ22 marker (15 out of 44 informative cases), which was detected by means of PCR, allele loss of the p53 gene was found (12 out of 15 informative cases). In 5 out of 13 tumors with cytogenetic alterations in 17p, allele loss of the p53 gene was found, with the YNZ22 marker being unaffected. In one of these tumors, the i(17q) marker was found, and in the remaining four tumors, 17p translocations were detected. In 4 out of 5 tumors with translocations affecting 17p, the t(17;20)(q21;p12) translocation was detected. The informativeness of the screening for 17p translocations, using PCR for the YNZ22 locus, and the reasons for discrepancy between the data of PCR and cytogenetic analyses are discussed.

Alleles↗
PubMed1993

[Ultrastructural study of explants of carcinoma of the large intestine during prolonged organ cultivation].

The electron microscopical study on organ cultures of colonic carcinoma has shown that tumour cells form typical for this kind of tumours glandular-like structures which consist of ultrastructural differentiated cells with organospecific features of brush-border and goblet cell types. Depending on the terms of cultivation the consecutive stages of ultrastructural differentiation have been retraced starting from undifferentiated cells (the 5th day of the experiment) up to structurally matured differentiated cells (the 7th-9th days of experiment). The tumour growth in the organ cultures is realized mainly by an explant itself building up processes from its peripheral cell lining and its invagination inside a piece. Glandular-like structures which are forming on the ends of processes and invaginations have undergone further separation. The question of monoclonal origin of colonic carcinoma in organ cultures is discussed.

Carcinoma↗
PubMed1992

Distribution of individual components of basement membrane in human colon polyps and adenocarcinomas as revealed by monoclonal antibodies.

Double-label immunofluorescence was used to monitor basement-membrane composition and integrity in 22 human colon polyps, 36 adenocarcinomas and 2 metastases. Cryostat sections were stained with polyclonal anti-laminin anti-serum combined with monoclonal antibodies (MAbs) to all major basement-membrane components (laminin, entactin/nidogen, collagen type IV and large heparan sulfate proteoglycan), as well as to keratin 8. In all adenocarcinomas, including mucinous, basement membranes were altered more at the invasive front than in the parenchyma. The degree of this alteration was inversely correlated with the level of tumor differentiation. An uncoordinated loss of basement membrane components (dissociation of markers), previously described by us in rat colon adenocarcinomas, was also found in human tumors. In the great majority of adenocarcinomas a pronounced stromal reaction was seen. It was manifested by the presence of fibrillar deposits of basement-membrane components, mainly of collagen type IV and/or heparan sulfate proteoglycan. This reaction was never observed in polyps and may be derived from myofibroblasts reported to accumulate in colon cancer stroma. The combined use of antibodies to basement-membrane components and to a specific keratin may constitute an adequate immunohistochemical test for the presence of invasion, and may be useful in the histologic analysis of polyps, especially in dubious cases.

Adenocarcinoma↗
PubMed1991

[The ultrastructural factors of the individual prognosis in rectal cancer in patients following radical surgical treatment].

Multifactorial analysis of the prognostic diagnosis of 39 main clinical, morphological and ultrastructural traits in 109 patients with rectum carcinoma is performed on the basis of computer EC-1045/230 program and algorithmic complex. The optimal complex of the traits is established possessing the maximum information value for prognosis of the 2-, 3- and 5-year survival of patients with this tumour. Three rules are formed for the individual prognosis of a favourable and unfavourable issue of the disease after the radical surgery. The value (in %) of these rules for the prognosis was determined: 79,86 and 92% for the 2-, 3- and 5-year survival, respectively. This is the precision with which one or another prognosis can be predicted.

Adenocarcinoma↗
PubMed1990

[Melanomas of the anorectal region].

Melanoma of the anorectal region is a rare disease which makes up 1.8% of all rectal malignancies and 1.4% of all cases of melanoma. Surgery is the only radical procedure for the treatment of anorectal melanoma. Abdomino-perineal extirpation of the rectum proved most radical. Overall five-year survival rate was 17.0 +/- 5.3%.

Adult↗
PubMed1990

[Malignant nonepithelial tumors of the rectum].

Nonepithelial malignancies of the rectum are extremely rare making up 0.34% of all rectal neoplasms only. Clinical course, diagnosis and treatment of 8 patients with rectal sarcoma are described. Electron microscopy is helpful in differentiating between various types of sarcoma.

Adult↗
PubMed1990

[Carcinoid of the rectum].

Rectal carcinoid is an extremely rare neoplasm which makes as few as 0.4% of all rectal malignancies. Morphological criteria of malignity of these tumors are unclear. Surgery proved the only radical method of treatment.

Adult↗
PubMed1989

[Focal fibrous mesothelioma of the pleura (a morphological study of 7 cases].

Seven focal pleural tumours are studied histochemically, immunohistochemically and electron microscopically (EM). A great variety of histological and EM structures was found: areas resembling fibromas, fibrous histiocytomas, hemangiopericytomas, etc. The EM signs of the abortive mesothelial differentiation were found in the tumour cells. The use of the term "localised fibrous mesothelioma" seems to be justified. It is necessary to distinguish morphologically diffuse mesothelioma and localised fibrous mesothelioma that possess different clinical course and prognosis.

Adult↗
PubMed1989

[The character of expression of keratins 8 and 19 in normal and neoplastic enterocytes of the large intestine].

Synthesis of individual keratins (Nos. 8 and 19) was shown to continue in the simple epithelium of tumor cells by application of monoclonal antibodies in 20 cases of different patterns of human colonic malignancies. No correlation between the synthesis and degree of cataplasia of said cells was found. The increase in manifestations of cellular and structural anaplasia in tumor was matched by the enhanced intensity of cells' staining with antibodies. Application of said procedure in oncomorphological practice helps reliably evaluate the real extent of tumor spreading and detects invasion which other microscopic methods fail to do.

Adenocarcinoma↗
PubMed1989

[The prognostic significance of the ultrastructural characteristics of human rectal cancer].

A retrospective study of the ultrastructure of rectal tumors in patients with favorable and unfavorable prognosis was undertaken. It established favorable postoperative course and prognosis in tumors containing more than half undifferentiated cells. Conversely, tumors in which malignant cells with electron microscopy-identifiable signs of differentiation (retaining features of normal cells) prevailed and those containing equal fractions of well- and poorly differentiated cells involve early development of metastasis and sometimes recurrences.

Adenocarcinoma↗