Three-Dimensional Reconstruction of the Superficial Multicentric Basal Cell Carcinoma Using Serial Sections and a Computer

Transition from cylindroma to spiradenoma in CYLD‐defective tumours is associated with reduced DKK2 expression

“…Here, in keeping with these data, we have shown that cylindromas and spiradenomas represent extremes of a spectrum of tumour organization. We have shown that islands of cylindroma cells grow as contiguous structures, a finding consistent with the growth pattern found in sporadic hair follicle tumours such as basal cell carcinoma 25, 26. An extension of this concept is the finding that cylindromas and spiradenomas grow in direct connection with each other, which accounts for the recurrent finding that features of both tumours are found in the same specimen, termed spiradenocylindroma.…”

Thickness of superficial basal cell carcinoma (sBCC) predicts imiquimod efficacy: a proposal for a thickness-based definition of sBCC

“…24,25 This presumption was subsequently disproved using computer-assisted three-dimensional reconstructions. 26 According to the current World Health Organization (WHO) classification, 'The histopathology consists of superficial lobules of basaloid cells which project from the epidermis or from the sides of follicles or eccrine ducts into the dermis and are surrounded by loose myxoid stroma. The lobules are usually confined to the papillary dermis.'…”

Evidence that superficial basal cell carcinoma is monoclonal from analysis of the Ptch1 gene locus

“…Thus, one could not logically determine whether an excised superficial BCC with a tumour nest < 1 mm from a resection margin was any more prone to recur than one where the nest was > 1 mm away. However, if the nests all connect in three dimensions 2 and are monoclonal, then there is a rational basis for understanding the pattern of growth of this tumour. The most simplistic interpretation is that cells proliferate and extend away from a founding cell within the epidermis in a radial fashion, punctuated by the occasional downgrowth of nests.…”

“…Reconciling the multifocal pattern of growth with a monoclonal origin is difficult. No studies addressing whether this BCC subtype is monoclonal have been performed, but computer‐assisted reconstruction of these tumours from serial histological sections helps to resolve this issue by indicating that the nests are all interconnected in three dimensions, 2 supporting the concept of a monoclonal proliferation. The proposal that such widely spaced tumour nests could be monoclonal is also supported by the fact that normal epidermis can contain genotypically identical patches of keratinocytes that are of the order of thousands of cells across 3,4 .…”