title: Estimation of thyroglobulin in lymph node aspirates: Pilot experience from a tertiary referral cancer center.
abstract: BACKGROUND
  Assessment of cervical lymph node involvement in patients with thyroid cancer either during preoperative surgical mapping or detection of recurrences during follow-up is a crucial step in the management of differentiated thyroid cancers (DTCs). In most patients, fine needle aspiration cytology (FNAC) confirms the presence of metastasis in lymph node. However, in cases of paucicellular lymph node aspirate or discordant sonogram and cytology results, thyroglobulin (Tg) measurement in the lymph node aspirate (FNA-Tg) is useful and a value >1 ng/ml is considered consistent with metastatic disease.
  
  
  BACKGROUND
  The addition of FNAC to the US improves the specificity, but 5-10% are nondiagnostic and 6-8% rate of false-negative results. Several studies have reported that the detection of Tg in FNA-needle washes improves the evaluation of suspicious lymph nodes in patients with DTC.Data from Indian centers on FNA-Tg are limited.
  
  
  OBJECTIVE
  We piloted the utility of FNA-Tg in patients with sonographically suspicious cervical lymph node enlargement in the setting of suspicious thyroid nodule or in the follow-up of thyroid cancer.
  
  
  METHODS
  Prospective data collection.
  
  
  RESULTS
  We measured Tg in 13 lymph node aspirates (12 patients, 10 females) among whom 4 patients had a total thyroidectomy and 1 had a hemithyroidectomy. Eight of the 13 lymph node aspirates had FNA-Tg values >150 ng/ml, all of them had unequivocal malignant cytology and four among them had proven metastatic DTC on surgical pathology. The median FNA-Tg of the patients with malignant cytology was 7550 ng/ml with a range of 162-30,000 ng/ml. Among the remaining 5 lymph node aspirate, 2 lymph nodes showed cytological features suggestive of reactive lymphadenitis (FNA-Tg <0.2 ng/ml) and were not operated, 1 had a high-grade malignancy consistent with anaplastic thyroid cancer (FNA-Tg <0.2 ng/ml), and 2 had nondiagnostic cytology (one had non-caseating granuloma on surgical pathology [FNA-Tg 1.3 ng/ml] and in the other patient [FNA-Tg <0.2 ng/ml] surgical intervention was deferred).
  
  
  CONCLUSIONS
  FNA-Tg was concordant with positive cytology in all patients with DTC and may serve as a useful tool in patients with negative and nondiagnostic cytology to guide surgical management.
authors.affiliation: Department of Endocrinology, Diabetes and Bariatric Medicine, Narayana Health City, Bangaluru, Karnataka, India.
authors.forename: Subramanian
authors.initials: S
authors.lastname: Kannan
authors.affiliation: Head and Neck Surgical Oncology and Reconstructive Surgery, Narayana Health City, Bangaluru, Karnataka, India.
authors.forename: Subhra
authors.initials: S
authors.lastname: Chauhan
authors.affiliation: Head and Neck Surgical Oncology and Reconstructive Surgery, Narayana Health City, Bangaluru, Karnataka, India.
authors.lastname: Naveen
authors.affiliation: Department of Laboratory Medicine, Narayana Health City, Bangaluru, Karnataka, India.
authors.forename: B S
authors.initials: BS
authors.lastname: Latha
authors.affiliation: Department of Pathology, Narayana Health City, Bangaluru, Karnataka, India.
authors.forename: Nalini
authors.initials: N
authors.lastname: Raju
authors.affiliation: Head and Neck Surgical Oncology and Reconstructive Surgery, Narayana Health City, Bangaluru, Karnataka, India.
authors.forename: Naveen Hedne
authors.initials: NH
authors.lastname: Chandrasekhar
authors.affiliation: Head and Neck Surgical Oncology and Reconstructive Surgery, Narayana Health City, Bangaluru, Karnataka, India.
authors.forename: Vikram
authors.initials: V
authors.lastname: Kekatpure
authors.affiliation: Head and Neck Surgical Oncology and Reconstructive Surgery, Narayana Health City, Bangaluru, Karnataka, India.
authors.forename: Moni Abraham
authors.initials: MA
authors.lastname: Kuriakose
authors.affiliation: Department of Radiology, Narayana Health City, Bangaluru, Karnataka, India.
authors.forename: P
authors.initials: P
authors.lastname: Manjunath
keywords: Cytology; differentiated thyroid cancer; lymph node aspirate; thyroglobulin