Confocal laser scanning microscopic observation of angioarchitectures in human thyroid neoplasms

Confocal laser scanning microscopy (CLSM) was employed to study the blood v ascular system of human thyroid tumors. CLSM observation combined with immu nohistochemistry for type IV collagen clearly visualized 3-dimensional imag es of the microvascular structures. CLSM observation showed that normal thy roid follicles were tightly covered by branching microvessels, whereas micr ovessels in follicular adenomas were more prominent and more irregular in s hape. Microfollicular adenomas showed that neoplastic small follicles were attached to the capillaries and had a "grape-like" appearance. Strikingly w ell-developed vascular networks were seen in neoplastic follicles of papill ary carcinomas. Interestingly, papillae of papillary carcinoma occasionally contained contained aggregated vascular complexes (glomeruloid structure) composed of tortuous, densely packed, and irregularly arranged small vessel s. Such aggregated vascular complexes ic ere seen in 5 of 7 papillary carci noma tissues but not in other histological thyroid turners. Our findings in dicate that the fundamental vascular pattern correlates well with the growt h pattern, suggesting an interdependence between parenchyma and stroma char acteristic for thyroid tumors. CLSM observation combined with immunohistoch emistry may contribute to a better understanding of morphological character istics of angioarchitecture in human surgical materials. Copyright (C) 1999 by W.B. Saunders Company.