LYVE-1 immunohistochemical assessment of lymphangiogenesis in endometrial and lung cancer.

AIMS/METHODS: Normal and malignant pulmonary and endometrial tissues were analysed for lymphatic vessels to assess the process of lymphangiogenesis and its role at these sites, using specific immunostaining for LYVE-1 and the panendothelial marker CD31. RESULTS: Lymphatics were clearly demonstrated in some normal tissues (myometrium, bronchial submucosa, and intestinal submucosa), but not in others (endometrium and alveolar tissue). LYVE-1 positive lymphatic vessels were detected at the tumour periphery of endometrial and lung carcinomas, but not within the main tumour mass. Double staining for LYVE-1 and the MIB1 proliferation marker revealed a higher proliferation index in lymphatic endothelial cells at the invading front of endometrial carcinomas, compared with myometrial areas distal to the tumour. Lung and endometrial carcinomas did not have an intratumorous lymphatic network. CONCLUSIONS: Although lymphangiogenesis may occur at the invading tumour front, incorporated lymphatics do not survive. Therefore, the dissemination of cancer cells through the lymphatics may occur by invasion of peripheral cancer cells into the adjacent normal lymphatics, or through shunts eventually produced at the invading tumour front as a consequence of active angiogenesis and lymphangiogenesis.

Assessment of vascular maturation in lung and breast carcinomas using a novel basement membrane component, LH39.

LH39, is a monoclonal antibody recognizing an epitope located at the lamina lucida of mature small veins and capillaries but not in newly- formed vessels of several pathological conditions including cancer. We examined the ratio of mature/immature vessels in 50 breast and 81 lung carcinomas and correlated the vascular maturation index (VMI) to different clinicopathological variables including angiogenesis. Mature vessels were defined by staining with antibodies to both LH39 and CD31, using double immunohistochemistry, whereas immature vessels stained only for CD31. VMI was defined as the percentage fraction of mature vessels (LH39 positive)/total number of vessels (CD31 positive). VMI in breast carcinomas ranged from 0-47% (median 8.75%), which was significantly lower than that observed in the normal breast cases (range 54%-70%; median 68%). The median VMI in the non-small cell lung carcinomas was 46% (range 15%-90%). There was a significant inverse correlation between high tumor VMI and absence of nodal involvement in both breast and lung tumors examined (p=0.01). Thymidine phosphorylase (TP) expression, but not vascular endothelial growth factor (VEGF) expression, was related to a low VMI showing an intense vascular remodeling in TP expressing cases. Thus, assessment of vessel maturation might be complementary to microvessel number to aid the identification of patients who might benefit from specific antiangiogenic therapies or vascular targeting treatment.

Assessment of vascular maturation in non-small cell lung cancer using a novel basement membrane component, LH39: correlation with p53 and angiogenic factor expression.

Angiogenesis, the formation of new vessels, has been demonstrated to be a potent and independent indicator of prognosis in non-small cell lung cancer patients. The extent of differentiation of the tumor vessels may affect access of peripheral white cells and egress or invasion of tumor cells. This has not been assessed in relation to tumor microvessel density or other variables and may be a marker of vascular remodeling. LH39 is a monoclonal antibody recognizing an epitope located at the lamina lucida of mature small veins and capillaries but not in newly formed vessels. We examined the ratio of mature:immature vessels in 81 non-small cell lung carcinomas and correlated the vascular maturation index (VMI) to different clinicopathological variables including angiogenesis. Mature vessels were defined by staining with antibodies to both LH39 and to CD31, using double immunohistochemistry, whereas immature vessels stained only for CD31. VMI was defined as the percentage fraction of mature vessels (LH39 positive)/total number of vessels (CD31 positive). The median VMI in lung carcinomas was 46% (range, 15-90%). There was a significant inverse correlation between high VMI and low thymidine phosphorylase expression (P = 0.0001), high VMI and nuclear p53 negativity (P = 0.01), high VMI and low angiogenesis (P = 0.0001), as well as between high VMI and absence of nodal involvement (P = 0.01). Low angiogenesis and high VMI were associated with a significantly better outcome (P = 0.0001 and P = 0.02, respectively). These findings show that there is a wide variation in the differentiation of tumor vasculature in lung carcinomas, and VMI gives new information on the degree of active tumor vascular remodeling independently from microvessel quantitation.

Comparative evaluation of angiogenesis assessment with anti-factor-VIII and anti-CD31 immunostaining in non-small cell lung cancer.

Anti-Factor VIII vessel immunostaining has been widely used in the detection of angiogenesis in non-small cell lung cancer and other tumors. Several new antibodies have shown a higher sensitivity, and anti-CD31 has recently been proposed to be the standard for microvessel study. In the present study, we comparatively evaluated the two antibodies in 134 cases of early operable non-small cell lung cancer. The F8/86 (anti-Factor VIII-associated antigen) and JC70 (anti-CD31) MoAbs were used in paraffin-embedded material. Eye appraisal of vascular grade (VG) and microvessel score (MS) was performed by three experienced pathologists. Different cutoff points were used for the analysis of VG and MS correlation with nodal involvement, overall survival, and thymidine phosphorylase expression. Intra- and interobserver variability was minimal for both antibodies. MS and VG were significantly correlated with each other. However, 54 and 22% of cases with high anti-CD31 VG or high MS, respectively, had low vascularization on anti-Factor VIII assessment. Anti-CD31 scoring was significantly associated with nodal involvement and overall survival for all cutoff points considered, which was not verified for anti-Factor VIII staining. VG was the most significant indicator of nodal involvement and survival for both antibodies. Tumors with high VG by anti-CD31 but low or medium VG by anti-Factor VIII behaved as tumors of high neoangiogenesis, defining a poor prognosis (P = 0.005) despite the failure of anti-factor VIII antibody to highlight intense neoangiogenesis. Anti-CD31 MS significantly associated with thymidine phosphorylase overexpression (P = 0.01), whereas no correlation was found for anti-Factor VIII counting. It was concluded that anti-CD31 microvessel immunostaining has several advantages over anti-Factor VIII, being a more sensitive method for highlighting small, immature microvessels or single endothelial cells. This could be of importance in revealing possible correlation of tumor angiogenesis with metastatic behavior, prognosis, or angiogenic factor overexpression. Vascular grading was the best method for neovascularization assessment, efficiently defining groups of tumors with aggressive clinical course.

Carcinoma of the cervix uteri: an assessment of the relationship of tumour proliferation to prognosis.

The aim of this study was to ascertain whether assessing the growth fraction of cervical carcinoma of 28 patients, using antibody Ki-67, would be of value in clinical practice. The results showed no relationship between growth fraction and age, clinical stage, lymph node involvement or short term (3-5 years) survival.

The utility of Ki67 immunostaining, nuclear organizer region counting, and morphology in the assessment of follicular lymphomas.

Three methods, the enumeration of large non-cleaved cells (LNCC), the enumeration of nucleolar organizer regions (AgNORs), and the estimation of the percentage of Ki67-positive cells, have been compared on a series of 36 follicular lymphomas for their utility in subclassification. All three methods produced similar subdivisions to those obtained using the histological classification of the Working Formulation for clinical usage. Twenty cases have been followed clinically to assess any relationship between these parameters and short-term (less than 4 years) survival. Each technique showed a trend towards identifying patients with a poor short-term prognosis with no one method being superior to any other. Unless larger series with longer follow-up suggest otherwise, there is no indication to use either the AgNOR or Ki67 methods which offer no advantage over the simple and inexpensive Working Formulation or Berard's LNCC counting.

Carcinoma of the cervix uteri: an assessment of tumour proliferation using the monoclonal antibody Ki67.

Thirty-one cervical biopsies of invasive carcinoma have been studied by immunohistochemical means using the monoclonal antibody Ki67 to determine tumour cell proliferation rates. A wide range (10-50%) in the extent of Ki67 staining (expressed as the percentage of labelled tumour cells) was observed indicating considerable variation on tumour growth rates. There was no significant relationship between the percentage of positive cells and conventional histological parameters such as cell type or tumour differentiation. Immunostaining with monoclonal antibody Ki67 therefore provides a new approach to the assessment of cervical tumour biopsies which will require long term clinical follow-up to establish its prognostic significance.