Microvessel Density and Area in Pituitary Microadenomas

Jasek, Ewa; Furgał-Borzych, Alicja; Lis, Grzegorz; Litwin, Jan A.; Rzepecka-Woźniak, Ewa; Trela, Franciszek

doi:10.1007/s12022-009-9091-1

Cited by 12 publications

(6 citation statements)

References 25 publications

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“…Low vascularization is a peculiar situation for tumors despite their benign nature, as even premalignant lesions like precarcinomas of the cervix and breast have increased MVD [ 60 , 61 ]. However, some benign tumors that hardly ever progress to malignancy were reported with lower vascular density when compared to normal tissue [ 62 – 64 ]. Nevertheless, even though vascular area was lower in pituitary tumors compared to the normal gland, vessel size proportion was markedly different in the normal and tumoral pituitary.…”

Section: Angiogenic Factors In Human Pituitary Adenomasmentioning

confidence: 99%

Angiogenesis in Pituitary Adenomas: Human Studies and New Mutant Mouse Models

Cristina

Luque

Demarchi

et al. 2014

International Journal of Endocrinology

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The role of angiogenesis in pituitary tumor development has been questioned, as pituitary tumors have been usually found to be less vascularized than the normal pituitary tissue. Nevertheless, a significantly higher degree of vasculature has been shown in invasive or macropituitary prolactinomas when compared to noninvasive and microprolactinomas. Many growth factors and their receptors are involved in pituitary tumor development. For example, VEGF, FGF-2, FGFR1, and PTTG, which give a particular vascular phenotype, are modified in human and experimental pituitary adenomas of different histotypes. In particular, vascular endothelial growth factor, VEGF, the central mediator of angiogenesis in endocrine glands, was encountered in experimental and human pituitary tumors at different levels of expression and, in particular, was higher in dopamine agonist resistant prolactinomas. Furthermore, several anti-VEGF techniques lowered tumor burden in human and experimental pituitary adenomas. Therefore, even though the role of angiogenesis in pituitary adenomas is contentious, VEGF, making permeable pituitary endothelia, might contribute to adequate temporal vascular supply and mechanisms other than endothelial cell proliferation. The study of angiogenic factor expression in aggressive prolactinomas with resistance to dopamine agonists will yield important data in the search of therapeutical alternatives.

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Section: Angiogenic Factors In Human Pituitary Adenomasmentioning

confidence: 99%

Angiogenesis in Pituitary Adenomas: Human Studies and New Mutant Mouse Models

Cristina

Luque

Demarchi

et al. 2014

International Journal of Endocrinology

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“…MVD is one of the most widely used estimators of tumor microvascularity in two-dimensional histological sections [5, 25]. However, MVD has several substantial limitations mainly owing to the complex biology of tumor microvasculature [26] and the irregular geometry that microvascular systems assume in real space [27].…”

Section: Discussionmentioning

confidence: 99%

Correlations of Vascular Architecture and Angiogenesis with Pituitary Adenoma Histotype

Takano

Akutsu

Hara

et al. 2014

International Journal of Endocrinology

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Vascular endothelial growth factor (VEGF) is a potent angiogenic factor in solid tumors. However, its role in angiogenesis in pituitary adenoma is controversial. Angiogenesis in solid tumors including pituitary adenoma is commonly evaluated by microvascular density (MVD). Here, we evaluated MVD and the role of VEGF in vascular architecture in 51 pituitary adenomas (24 nonfunctioning, 13 prolactin-secreting, 10 growth hormone-secreting, 3 adrenocorticotropic hormone-secreting, and 1 thyroid-stimulating hormone-secreting). Paraffin sections were stained with CD34 and VEGF. MVD and vascular architecture parameters (vessel area, diameter, perimeter, and roundness) were evaluated in CD34-stained sections. Immunohistochemistry showed 27/51 tumors (53%) were VEGF-positive. There were no significant differences in MVD, any vascular parameter, or adenoma volume between VEGF-positive and VEGF-negative tumors. VEGF mRNA expression was significantly higher in VEGF-positive tumors. There were no significant correlations between VEGF mRNA expression and MVD or vascular parameters. However, vessel diameter and perimeter were significantly larger in prolactin-secreting than nonfunctioning and growth hormone-secreting macroadenomas. The difference in vessel diameter was observed among both VEGF-positive and all adenomas (micro- and macroadenoma). Thus, VEGF may have limited roles in the development of vascular architecture and tumor angiogenesis in pituitary adenomas, but the differences in vessel architecture by histotype (i.e., larger vessel diameter and perimeter in prolactin-secreting adenomas) suggest the hormonal regulation of vessel architecture rather than angiogenesis

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“…Nevertheless, the difference between the two values was not statistically significant given the small size of the study sample. ACTH tumors exhibited the highest MVD values and lowest capillary volume, whereas PRL tumors had the highest capillary value (28). These two tumor subtypes have different VEGF levels.…”

Section: Discussionmentioning

confidence: 99%

Pharmacokinetic analysis for the differentiation of pituitary microadenoma subtypes through dynamic contrast‑enhanced magnetic resonance imaging

et al. 2019

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The value of pharmacokinetic parameters derived from dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) in distinguishing pituitary microadenoma subtypes was investigated in the present study. Pathology and follow-up outcomes were applied as the gold standard for differentiating between 76 patients with pituitary microadenomas (38 prolactin-producing tumors, 17 adrenocorticotropic hormone adenomas and 21 growth hormone-producing tumors) and 20 patients with normal pituitary glands. DCE-MRI was conducted to obtain the following quantitative permeability parameters: Volume transfer constant (K trans ), rate constant (K ep ) and extracellular extravascular volume fraction (V e ). Among the 76 cases included, 61 were visually diagnosed using conventional MRI. The K trans , K ep and V e of the microadenoma cases were 0.472±0.292/min, 0.765±0.359/min and 0.792±0.345, respectively. The K trans , K ep and V e of the normal control group were 0.902±0.238/min, 1.208±0.599/min and 0.928±0.378, respectively. The K trans and K ep of patients with microadenomas were significantly lower compared with those of the normal controls (P<0.05). However, the V e of the two groups did not significantly differ. Subtype differentiation analysis revealed that patients with growth hormone-producing tumors exhibited the highest K trans value (P<0.05). K ep significantly differed between growth hormone-producing tumors and the other two subtypes (P<0.05), but did not significantly differ among three subtypes. Receiver-operator characteristic analysis indicated that the area under the curve values of K trans and K ep were 0.884 and 0.728, respectively. Sensitivity and specificity were 95.0 and 82.6%, respectively, when K trans was set to 0.614/min as the cut-off value, and when the K ep cut-off value was set to 0.985/min, sensitivity and specificity were 60.0 and 81.3%, respectively. In conclusion, K trans and K ep derived from DCE-MRI could be applied to detect and identify microadenoma subtypes. K trans better reflects the blood perfusion alterations exhibited by patients with different microadenoma subtypes.

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Microvessel Density and Area in Pituitary Microadenomas

Cited by 12 publications

References 25 publications

Angiogenesis in Pituitary Adenomas: Human Studies and New Mutant Mouse Models

Angiogenesis in Pituitary Adenomas: Human Studies and New Mutant Mouse Models

Correlations of Vascular Architecture and Angiogenesis with Pituitary Adenoma Histotype

Pharmacokinetic analysis for the differentiation of pituitary microadenoma subtypes through dynamic contrast‑enhanced magnetic resonance imaging

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