title: Regional recurrence after lymphadenectomy for clinically evident lymph node metastases from papillary thyroid cancer: a cohort study.
abstract: BACKGROUND
  The presence of lymph node (LN) metastases in papillary thyroid cancer (PTC) has limited prognostic utility for predicting disease-specific survival. Pathologic features of the LNs beyond their presence and location do not factor into the AJCC staging system. Most LN metastases are microscopic. The natural history of patients with PTC and clinically evident LN metastases (CELNM) has not been well characterized.
  
  
  METHODS
  Patients with CELNM from PTC undergoing lymph node dissection (LND) by a single surgeon were identified (1999-2009). Patients with and without recurrence were compared by clinical and pathological factors using Student's t test, Fisher's exact test, and Chi-squared test. Logistic regression was used to determine the association between recurrence and CELNM after adjustment for confounders.
  
  
  RESULTS
  Ninety-two patients were identified who underwent surgery for CELNM. With a median follow-up of 27.5 months, 27 patients (29%) developed regional nodal recurrence with no disease-related deaths. Patients with and without recurrence were similar with respect to all clinical and pathologic variables analyzed except for the number of metastatic LNs. With a similar number of LNs sampled in both groups, the mean number of metastatic LNs was significantly higher in the group of patients with recurrence versus those without recurrence (12 vs. 6, p = 0.03) and remained significantly associated with the likelihood of recurrence (p = 0.009) in the logistic regression model.
  
  
  CONCLUSIONS
  Patients with CELNM have an appreciable incidence of early regional cervical recurrence but not distant metastases. Among clinical and pathological factors evaluated, the number of metastatic LNs is associated with recurrence.
authors.affiliation: Department of Surgery, Hospital of the University of Pennsylvania, Philadelphia, PA, USA.
authors.forename: Parth K
authors.initials: PK
authors.lastname: Shah
authors.forename: Kinjal K
authors.initials: KK
authors.lastname: Shah
authors.forename: Giorgos C
authors.initials: GC
authors.lastname: Karakousis
authors.forename: Caroline E
authors.initials: CE
authors.lastname: Reinke
authors.forename: Rachel R
authors.initials: RR
authors.lastname: Kelz
authors.forename: Douglas L
authors.initials: DL
authors.lastname: Fraker
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002277:Carcinoma; D002291:Carcinoma, Papillary; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D016015:Logistic Models; D008197:Lymph Node Excision / Q000009:adverse effects / Q000706:statistics & numerical data*; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000453:epidemiology* / Q000209:etiology / Q000473:pathology; D009367:Neoplasm Staging; D015996:Survival Rate; D000077273:Thyroid Cancer, Papillary; D013964:Thyroid Neoplasms / Q000401:mortality* / Q000473:pathology / Q000556:secondary*; D055815:Young Adult