Clinical Behavior of Papillary Thyroid Carcinoma Smaller than 1.5 cm / 대한이비인후과학회지

ABSTRACT

BACKGROUND AND OBJECTIVES: With the increasing use of high resolution sonography and fine needle aspiration biopsy, the proportion of newly diagnosed thyroid papillary carcinomas have increased. However, it is not entirely clear whether microcarcinomas detectable by the above technology the should be considered a threshold for risk evaluation. The purpose of this study is to evaluate the clinical behavior of papillary carcinomas smaller than 1.5 cm. SUBJECTS AND METHOD: A retrospective chart review was conducted for 181 patients who underwent surgery for thyroid cancer and was proven to have papillary carcinoma smaller than 1.5 cm in size from 1997 to 2006. The patients were divided into 3 groups according to cancer size. The patient's gender, age, surgical method, pathology, initial neck node and neck recurrence was analyzed by chi-square test, analysis of variance (ANOVA) test and multinomial logistic regression analysis. RESULTS: Progressively increasing frequency of signs of tumor aggressiveness (multifocal, bilateral, extracapsular spread) was observed with increasing size. The rate of lymph node metastasis increased also, but it did not reach a significant value. Despite the increasing rate of aggressiveness and lymph node metastasis, there was no significant difference in recurrence between these groups. CONCLUSION: Although the long term outcome does not seem to directly depend on tumor size in these small thyroid cancers, a progressing frequency of aggressiveness with increasing cancer size at presentation is evident.