Most, if not all cancers are preceded by a precancerous lesion, which has a number of biologic and morphologic features that are different from the fully developed cancer. Precancers are much easier to treat than cancers. By treating precancers, we can prevent cancers from developing.
In prior blog posts, I have discussed the biological properties of the precancers. One of these properties is an observed co-occurrence with cancers. Basically, if a particular type of cancer arises from a precancer, you would expect to see some instances wherein the cancer co-occurs with the precancer (i.e., where the cancer can be seen adjacent to its precancer). Co-occurrence of precancer and cancer is rare because cancers overgrow and replace their precancers.
Papillary thyroid carcinoma accounts for about 80% of thyroid cancers diagnosed in the U.S. Until recently, little attention has been directed to the putative precursor lesion of this cancer. A recent paper by Cameselle-Teijeiro and associates described a case of papillary thyroid carcinoma adjacent to a focus of solid cell next hyperplasia (1). The authors microdissected both lesions and found the same BRAF mutation in the solid cell nests and in the adjacent cancer.
Their findings suggest that solid cell nest hyperplasia is the precancer lesion for the adjacent cancer.
In their case report, the particular type of papillary carcinoma was the follicular variant of papillary microcarcinoma. More research is necessary to answer the following questions:
1. Is their observation generalizable (i.e., can it be shown that solid cell nest hyperplasia is found in additional cases of thyroid carcinoma)?
2. Does solid cell nest hyperplasia have all of the defining properties of a precancer?
3. If so, for which thyroid cancers is solid cell nest hyperplasia the precancer (i.e., is it the exclusive precancer for the follicular variant of papillary microcarcinoma, or is it the precancer of other types of cancers that arise from thyroid follicle cells)?
 Cameselle-Teijeiro J, Abdulkader I, P‚rez-Becerra R, V zquez-Boquete A, Alberte-Lista L, Ruiz-Ponte C, Forteza J, Sobrinho-Simoes M. BRAF mutation in solid cell nest hyperplasia associated with papillary thyroid carcinoma. A precursor lesion? Hum Pathol 40:1029-1035, 2009.
In June, 2014, my book, entitled Rare Diseases and Orphan Drugs: Keys to Understanding and Treating the Common Diseases was published by Elsevier. The book builds the argument that our best chance of curing the common diseases will come from studying and curing the rare diseases.
I urge you to read more about my book. There's a generous preview of the book at the Google Books site.
© 2010 Jules Berman
tags: papillary carcinoma of the thyroid, papillary carcinoma of thyroid, thyroid cancer, precancer, thyroid precancer, precancerous, premalignant, early cancer, early lesions, pathology, pathogenesis, carcinogenesis, informatics, jules j berman, orphan drugs, rare diseases, genetic diseases, orphan diseases