Solid variant of papillary thyroid carcinoma - Incidence, clinical-pathologic characteristics, molecular analysis, and biologic behavior
ABSTRACT Solid variant is a rare and poorly characterized variant of papillary thyroid carcinoma. In this study we analyzed 20 primary cases of the solid variant of papillary carcinoma found in a series of 756 papillary carcinomas operated at the Mayo Clinic between 1962 and 1989. The criteria for classification included predominantly (>70%) solid growth pattern of primary tumor, retention of cytologic features typical of papillary carcinoma, and absence of tumor necrosis. For each case of the solid variant, a control case of classical papillary carcinoma matched by age, sex, tumor size, and length of follow-up was selected. The follow-up ranged from 6 to 32 years. Two patients with the solid variant of papillary carcinoma (10%) died from disease 7 and 10 years after initial surgery, while another two patients (10%) are alive with lung metastases. In contrast, the control group had no cases with distant metastases or death from disease. Molecular analyses showed a similar prevalence of RET /PTC rearrangements in both groups. In conclusion, the solid variant of papillary carcinoma is associated with a slightly higher frequency of distant metastases and less favorable prognosis than classical papillary carcinoma. However, it should be distinguished from poorly differentiated thyroid carcinoma, which has a reported lower survival rate compared with the solid variant of papillary carcinoma.
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- "It has a slightly worse prognosis than the classical papillary type but much better than poorly differentiated carcinoma. It has the same nuclear morphology and immunohistochemical profile as the classical papillary type. Since it usually presents with a diagnostic dilemma and worse prognosis than classical variant, but much better than the other differentials mentioned above, histopathology should be given importance and this case report represents the same. "
ABSTRACT: Solid variant is a rare and poorly characterized variant of papillary thyroid carcinoma (PTC) and comprises approximately 3% of PTCs. It is more common in children and has high propensity for extrathyroidal metastasis. It is seen in higher proportion in post-radiation PTCs and has been seen in more than one-third of post Chernobyl radiation induced PTCs in some studies. It usually presents with differential diagnosis of poorly differentiated carcinoma versus anaplastic versus medullary thyroid carcinoma versus metastasis from extrathyroidal malignancy on fine needle aspiration cytology. This report describes a case of solid variant of PTC in a child who had no history of radiation exposure and shows the importance to be given to histopathology when the pre-operative diagnosis is not clear.10/2011; 26(4):196-8. DOI:10.4103/0972-3919.106707
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- "The solid variant of papillary thyroid carcinoma (PTC) is dominated by solid sheets of tumour cells showing typical nuclear features . Since this sub-type of PTC is a rare and poorly characterized, there is disagreement on its behaviour . An aggressive course may be suggested by its association to vascular invasion and extra-thyroidal extension in about one-third of cases . "
ABSTRACT: Papillary thyroid carcinoma (PTC) composed by predominant solid areas is diagnosed as a distinct variant on histological samples. Here we present a case of PTC recognized preoperatively by fine needle cytology as a solid variant. This diagnosis was made by combining cytology with the detection of the BRAFVK600-1E mutation, the molecular hallmark of the solid variant of PTC. Histological and molecular evaluation of the surgical specimen confirmed this pre-operative diagnosis. Thus combining cytology to BRAF molecular analysis is useful to refine the cytological diagnosis of this variant also on FNC specimens.CytoJournal 02/2008; 5:2. DOI:10.1186/1742-6413-5-2
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ABSTRACT: Some of the numerous examples that can be quoted are those on dysplasia in Barrett's esophagus, 6 grading of prostatic carcinoma, 7 grading of breast carcinoma, 8 diagnosis of hydatidiform mole, 9 and classification of thymic tumors. 10 On first sight, these results make surgical pathology look like a subjective, arbitrary, unscientific discipline, and therefore many surgical pathologists don't like them. I still get occasional snotty remarks about a study of the kind I did many years ago on proliferative ductal lesions of the breast. 11 Yet, I doubt whether burying our head in the sand is the solution. Perhaps it is the nature of the beast, and nothing can be done about it. 12 As Vickery 13 stated, some of the criteria on which we base those distinctions "may be indefinite and vulnerable to subjective morphologic interpretation." Or perhaps some of these studies will identify a specific problem that can be addressed. The various thyroid studies above quoted mainly deal with the diagnostic significance of certain morphologic nuclear features (herein referred to as PTC-type nuclei) in the diagnosis of papillary thyroid carcinoma (PTC). It is obvious from the results obtained that some experts have a much lower threshold for the identification and/or diagnostic significance of PTC-type nuclei than others. It may be of some interest to briefly recount the evolution that PTC-type nuclei have had in thyroid pathology until reaching their presently exalted status. Originally, and for the many decades that followed its description, PTC was diagnosed primarily on the basis of the presence of papillae, hence its name. Then people began noticing that these tumors had peculiar nuclei, which looked empty or optically clear. Ronald DeLellis 14 gave credit to Nancy Warner for drawing the amusing analogy between these nuclei and the eyes of Harold Gray's comic strip character, "Little Orphan Annie". Thus, the expression "Orphan Annie's eyes nuclei" became popular when referring to PTC, although the presence of papillae and other cytoarchitectural features (carefully listed and discussed in Vickery's authoritative review on the subject 13 ) were still regarded as important criteria for the diagnosis of PTC. However, with the passing of the years, PTC-type nuclei rose through the ranks, so to speak, to become the paramount criterion for the diagnosis of PTC. At present, a thyroid tumor can have a papillary, follicular, solid, trabecular or cribriform pattern of growth; it can be composed of large, small, oncocytic, clear, round, spindle or columnar cells; it can be encapsulated, minimally invasive or widely invasive; in sum, it can have any of those features and more, but as long as it has PTC-type nuclei it is thought to be a PTC or one of its innumerable variants.