Thyroid cancer is the most common cancer of the endocrine system accounting for approximately 1% of all cancers and 30–35% of head and neck cancers. Papillary thyroid carcinoma constitutes 80–85% of thyroid carcinomas and its ten-year survival rate is more than 90% [
While in the past TMPC was mostly found in the surgical specimens of thyroidectomies due to a benign disease and in the autopsy series, today the detection rate of TMPC has considerably increased due to the widespread use of high-resolution ultrasonography (USG) and fine-needle aspiration biopsy for nodules smaller than three millimeters [
One hundred nine patients operated with the diagnosis of papillary thyroid carcinoma between December 2009 and January 2014 were included in this study. The inclusion criteria were as follows: (1) tumor size less than or equal to one centimeter, measured via USG, (2) no clinical or radiological evidence of cervical lymphadenopathy (cN0), (3) younger than 80 years of age, (4) presence of more than six lymph nodes in the CLND specimen (if CLND was performed), and (5) no prior history of head and neck radiation or surgery. For multicentric tumors, one-centimeter criteria were applied to the single biggest tumor. Preoperative diagnosis was made in all patients via cytological evaluation of fine-needle aspiration biopsy (FNAB). Although FNAB is not generally required for tumors less than one centimeter in size, all our patients showed suspicious findings on USG such as irregular nodule surface or increased vascularity. The patients were evaluated both clinically and with USG and staged as cN0. We divided the patients into two groups according to the surgical procedure performed. The first group was the patients who underwent only total thyroidectomy (
The two groups were compared in terms of age, gender, tumor multicentricity, tumor size, and presence of lymphocytic thyroiditis. The CLND group was also further evaluated for lymph node metastasis.
We did not observe any morbidity related to hypocalcemia or recurrent nerve damage in the patients who has undergone CLND. All specimens were carefully evaluated for any presence of parathyroid tissue at the operating table before being sent to pathology.
SPSS 17.0 software was used for statistical evaluation. Intergroup evaluation was done using
Descriptive statistics of the patients included in this study are given in Table
Descriptive statistics of the patients (
Number (percentage) | |
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Gender | |
Female | 79 (72.5%) |
Male | 30 (27.5%) |
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Multicentricity | |
No | 88 (80.7%) |
Yes | 21 (19.3%) |
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Surgery | |
Total thyroidectomy + CLND | 56 (51.4%) |
Total thyroidectomy | 53 (48.6%) |
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Lymphocytic thyroiditis | |
Absent | 64 (58.7%) |
Present | 45 (41.3%) |
No statistically significant difference was found between the two study groups (total thyroidectomy versus total thyroidectomy + CLND) in terms of age, gender, tumor multicentricity, lymphocytic thyroiditis, tumor size, and number of nodules (Table
Comparison of age, gender, and multicentricity; presence of lymphocytic thyroiditis; tumor size; and number of nodules in the two patient groups.
Patient group | |||
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Total thyroidectomy ( |
Total thyroidectomy + CLND ( |
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Age (median, range) | 41.5 y (25–69 y) | 44.0 y (19–79 y) |
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Gender | |||
Female ( |
39 (49.4%) | 40 (50.6%) |
|
Male ( |
14 (46.7%) | 16 (53.3%) | |
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Multicentricity | |||
No ( |
45 (51.1%) | 43 (48.9%) |
|
Yes ( |
8 (38.1%) | 13 (61.9%) | |
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Lymphocytic thyroiditis | |||
Absent ( |
34 (53.1%) | 30 (46.9%) |
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Present ( |
19 (42.2%) | 26 (57.8%) | |
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Tumor size (median, range) | 8.0 (2–10) mm | 8.0 (2–10) mm |
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Number of nodules (median, range) | 1.0 (1–5) | 1.0 (1‐2) |
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The patients who received CLND as a part of their treatment are further analyzed by dividing this group into two subgroups according to metastatic status (absent/present). No statistically significant differences were found upon the comparisons of the two subgroups in terms of age, gender, tumor multicentricity, tumor size, number of nodules, and number of lymph nodes removed (Table
Further analyses of the patient group who underwent total thyroidectomy + CLND (
Metastases | |||
---|---|---|---|
Absent ( |
Present ( |
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Age (median, range) | 42.0 y (25–60 y) | 37.0 y (27–69 y) |
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Gender | |||
Female ( |
31 (77.5%) | 9 (22.5%) |
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Male ( |
12 (75.0%) | 4 (25.0%) | |
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Multicentricity | |||
No ( |
34 (79.1%) | 9 (20.9%) |
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Yes ( |
9 (69.2%) | 4 (30.8%) | |
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Lymphocytic thyroiditis | |||
Absent ( |
19 (63.3%) | 11 (36.7%) |
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Present ( |
24 (92.3%) | 2 (7.7%) | |
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Tumor size (median, range) | 8 (2–10) mm | 9 (5–10) mm |
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Number of nodules (median, range) | 1.0 (1–5) | 1 (1‐2) |
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Number of lymph nodes removed (median, range) | 6 (1–6) | 7 (6–17) |
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Papillary thyroid cancers with a diameter of less than ten millimeters are called thyroid micropapillary carcinoma (TMPC). In the recent years, the incidence of thyroid micropapillary carcinoma has increased [
Neck lymph node metastasis in TMPC was reported to be approximately 24% to central lymph nodes and 3.7% to lateral group lymph nodes [
Some authors argue that in case of intraoperative observation or palpation of lymph nodes in cN0 patients, the patients should be restaged as N+ and central neck dissection should be performed. However, it is emphasized that CLND should be performed by experienced hands [
In countries with endemic thyroiditis, enlarged lymph nodes are often observed in the central neck region and preoperative differentiation of metastatic or reactive lymph nodes is challenging. In this study, we observed that more than half of the patients who underwent CLND (26 out of 56) had lymphocytic thyroiditis, which would be expected to present with enlarged lymph nodes. However, by means of CNLD, we were able to detect the patients who had concurrent lymph node metastasis (two out of 26).
It has been claimed that both low thyroglobulin levels and low recurrence rates would be obtained by performing CLND at the primary operation and thus complications due to a secondary surgical intervention would decrease [
In the postoperative follow-up, the thyroglobulin and antithyroglobulin values are important markers for lymph node metastasis and are useful in planning radioactive iodine (RAI) treatment. Complete removal of tumor would ensure the lowest levels of these markers and optimize their use in the follow-up.
Various parameters are utilized while evaluating the prognosis of papillary thyroid carcinoma and the most commonly used parameters are age, gender, family history, tumor size, presence of extracapsular extension, and presence of metastasis. Although these parameters provide insight to the prognosis of disease, the most accurate evaluation is done through histopathological evaluation. Moreover, the prognostics factors do not include central lymph node metastasis. As recurrence is most commonly seen in the central neck, it might indicate inadequate surgery [
We advocate central group lymph node dissection when macroscopic lymph nodes are observed during the intraoperative evaluation of the patients with thyroid micropapillary carcinoma. If the tumor is unifocal, ipsilateral lymph nodes are dissected while if the tumor is multifocal, bilateral central lymph nodes are dissected. Since our team is experienced in this field, central lymph node dissections were performed with morbidity rates equivalent to total thyroidectomy. The actual disease stage was then determined by the evaluation of the lymph nodes in the surgical specimen. Although one might argue that this would not affect the prognosis, the additional information on the lymph node status of the patient would be useful in the follow-up and further planning of the treatment. In addition, performing dissection during the primary surgical treatment would prevent disease recurrence. Secondary benefits would be minimizing patients’ anxiety due to the possibility of a secondary operation and preventing morbidity due to secondary interventions.
In patients with lymph node metastases, the common feature of the metastases is being in the form of micrometastases. Tumor multicentricity, lymph node metastases, and distant metastases have been reported to be 20%–40%, 17%–43%, and 0.3%, respectively [
The authors declare that they have no competing interests.