title: Soft tissue invasion of papillary thyroid carcinoma.
abstract: Extrathyroidal extension (ETE) of papillary thyroid carcinoma (PTC) is common and clinical presentation can vary from minimal to extensive locoregional involvement. Although PTC is generally considered the most benign among all thyroid carcinomas, it may present with local invasion with poor prognosis. Our retrospective study involved 3267 PTC patients undergoing regular follow-up at Chang Gung Medical Center in Linkou, Taiwan. Among them, 269 were PTC cases with ETE, having tumors greater than 1 cm in size and treated with total or complete thyroidectomy with or without lymph node dissection for which the follow-up period was over 10 years. The mean age of 269 cases was 46.8 ± 15.1 (range 11-83 years) years. The number of females was 204 (75.8 %). Patients were categorized into minimal ETE (175 cases) and extensive ETE (94 cases) groups according to surgical findings and pathological reports. Mean follow-up period was 13.3 ± 5.5 (range 0.2-29.3) years, during which 28 (10.4 %) patients died of thyroid cancer; and 63 (23.4 %) of all-cause mortality. Multivariate analysis showed that age, gender, extensive ETE, and lymph node metastasis had a statistically significant effect on thyroid cancer mortality. Survival rates were significantly different between minimal ETE and extensive ETE groups (p < 0.0001). In conclusion, perithyroidal soft tissue involvement by PTC is an important factor that determines patient prognosis and a closer follow-up and more aggressive treatment is necessary for patients who are old, male, extensive ETE, and with lymph node involvement.
authors.affiliation: Division of Endocrinology and Metabolism, Department of Internal Medicine, Chang Gung Memorial Hospital, Chang Gung University, 5, Fu-Shin St., Kweishan County, Taoyuan Hsien, Taiwan, ROC. einjd@adm.cgmh.org.tw.
authors.forename: Jen-Der
authors.initials: JD
authors.lastname: Lin
authors.affiliation: Department of Pathology, Chang Gung Memorial Hospital, Chang Gung University, Kweishan County, Taiwan, ROC.
authors.forename: Chuen
authors.initials: C
authors.lastname: Hsueh
authors.affiliation: Department of General Surgery, Chang Gung Memorial Hospital, Chang Gung University, Kweishan County, Taiwan, ROC.
authors.forename: Tzu-Chieh
authors.initials: TC
authors.lastname: Chao
mesh_terms: D018263:Adenocarcinoma, Follicular / Q000556:secondary* / Q000601:surgery; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002291:Carcinoma, Papillary / Q000556:secondary* / Q000601:surgery; D002648:Child; D005260:Female; D006801:Humans; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009364:Neoplasm Recurrence, Local / Q000473:pathology* / Q000601:surgery; D009367:Neoplasm Staging; D011379:Prognosis; D011446:Prospective Studies; D012189:Retrospective Studies; D012983:Soft Tissue Neoplasms / Q000556:secondary* / Q000601:surgery; D015996:Survival Rate; D013964:Thyroid Neoplasms / Q000473:pathology* / Q000601:surgery; D013965:Thyroidectomy; D055815:Young Adult
keywords: Cancer-specific mortality; Radioactive iodide; Thyroglobulin; Total thyroidectomy