title: Patterns of structural recurrence in papillary thyroid cancer.
abstract: BACKGROUND
  Papillary thyroid carcinoma (PTC) is uncommonly associated with tumor-related mortality, although local recurrence can be a frequent and difficult problem. This study was conducted to clarify the pattern of structural locoregional recurrence in PTC.
  
  
  METHODS
  A retrospective cohort study of patients undergoing surgical intervention for PTC was undertaken. Data were collected from a comprehensive thyroid cancer database maintained within a single tertiary referral center. The primary outcome measure was cancer recurrence requiring surgical intervention. Secondary outcome measures were site of recurrence, time to recurrence, and risk factors for recurrence.
  
  
  RESULTS
  In the period 1980-2013, 1,183 patients with PTC were included in the study. The overall rate of structural recurrence requiring reoperative surgery was 7.9 %. The median time to reoperation was 31 months. Younger age, male gender, large primary tumor diameter, and number of positive lymph nodes at initial presentation were all significantly associated with disease recurrence. The lateral compartments (levels I, II, III, IV, V) were involved almost twice as frequently as the central compartment (level VI) (67 vs 32 %, P < 0.01). The distribution of recurrences was level I (1 %), level II (12 %), level III (18 %), level IV (18 %), level V (17 %), level VI (32 %), level VII (2 %).
  
  
  CONCLUSIONS
  In a center with a liberal approach to central compartment lymph node dissection for PTC, the lateral neck compartment is the most common site of structural recurrence requiring reoperative surgery.
authors.affiliation: University of Sydney Endocrine Surgery Unit, Royal North Shore Hospital, Suite 202, 69 Christie St., St. Leonards, Sydney, NSW, 2065, Australia, kruijffs@gmail.com.
authors.forename: Schelto
authors.initials: S
authors.lastname: Kruijff
authors.forename: Japke F
authors.initials: JF
authors.lastname: Petersen
authors.forename: Paul
authors.initials: P
authors.lastname: Chen
authors.forename: Ahmed M
authors.initials: AM
authors.lastname: Aniss
authors.forename: Roderick J
authors.initials: RJ
authors.lastname: Clifton-Bligh
authors.forename: Stan B
authors.initials: SB
authors.lastname: Sidhu
authors.forename: Leigh W
authors.initials: LW
authors.lastname: Delbridge
authors.forename: Anthony J
authors.initials: AJ
authors.lastname: Gill
authors.forename: Diana
authors.initials: D
authors.lastname: Learoyd
authors.forename: Mark S
authors.initials: MS
authors.lastname: Sywak
mesh_terms: D000328:Adult; D002277:Carcinoma / Q000401:mortality / Q000473:pathology* / Q000601:surgery; D002291:Carcinoma, Papillary; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D037981:Neck Dissection; D009364:Neoplasm Recurrence, Local / Q000209:etiology / Q000401:mortality / Q000473:pathology* / Q000601:surgery; D012189:Retrospective Studies; D012307:Risk Factors; D016019:Survival Analysis; D000077273:Thyroid Cancer, Papillary; D013964:Thyroid Neoplasms / Q000401:mortality / Q000473:pathology* / Q000601:surgery; D013965:Thyroidectomy; D013997:Time Factors; D016896:Treatment Outcome