Comparative study of single-center patients with thyroid metastases from colorectal cancer and previously reported cases in the literature

Abstract

BackgroundThyroid metastases from colorectal cancer (CRC) are rare, both in clinical practice and in the literature; hence, their diagnosis, appropriate treatment, and prognostic factors require further investigations.MethodsA retrospective analysis was performed for four cases of thyroid metastases from CRC, treated in our center between January 2005 and December 2015, and the relevant literature was searched using PubMed, resulting in the identification of 17 patients with detailed information available. The clinical data and follow-up information of our patients and the previously reported cases were collected and compared.ResultsThe median age of the 21 patients was 59 years (44.5 and 66 years for our patients and the previously reported cases, respectively). Fifteen (71.4%) primary tumors were distributed throughout the distal colon or rectum (75% [3/4] in our center and 70.5% [12/17] in the previously reported cases). According to our analysis, we found that 81.0% of patients (17/21) showed concomitant lung metastasis. Among them, all four patients in our center showed lung metastasis, and 75% (3/4) developed thyroid metastases after the lung metastasis. In the previously reported cases, the corresponding proportions were 76.5 and 76.5% (13/17) of patients, respectively. The median time after primary tumor diagnosis to thyroid metastasis development was 28 months (26 months in our center and 35 months in the previously reported cases). One patient with advanced CRC in our center died 5 months after the thyroid metastasis was identified, while the remaining three patients are currently alive (longest follow-up time, 27 months). The median survival time after thyroid metastasis during 3 years of follow-up of the previously reported 17 patients was 12 months. There was no difference in the overall survival between patients treated non-surgically (8/21) and patients undergoing thyroidectomy alone or thyroidectomy with adjuvant therapy (13/21) (p = 0.388). In addition, we found that the overall survival of the patients whose other metastases were treated with radical treatment was superior to that in those treated with palliative treatment (p = 0.022).ConclusionsThyroid metastases from CRC are rare in clinical practice and are a manifestation of advanced CRC. The prognosis of patients with thyroid metastases from CRC is related to various factors, including the grade of malignancy of the primary lesion, the presence of other metastases, and whether the metastases are timely diagnosed and a radical treatment strategy is employed.

Colon Cancer Metastatic to the Thyroid Gland in the Setting of Pathologically Diagnosed Papillary Thyroid Cancer: A Review and Report of a Case

“…A retrospective analysis of 21 detailed cases of thyroid metastasis from CRC conducted by Keranmu et al provides insight into certain patterns and associations of this neoplastic process. The median age of the patients at the time of diagnosis of thyroid metastasis was 59 years [7]. In this study, 71.4% of patients had a primary tumor distributed throughout the distal colon or rectum.…”

“…with the link between pulmonary and thyroid metastases of CRC described by Keranmu et al, provides a novel insight into the route of spread for this neoplastic process [2,7]. The most common distal metastatic location of CRC, excluding lymph nodes, is the liver followed by the lungs.…”

“…Given that clinical data suggest that thyroid metastasis is discovered after a known pulmonary metastasis, it is conceivable that the portal circulation allows the primary lesion to seed to the liver, from where it can disseminate systemically to the lungs and finally the thyroid. However, there have been reported cases of thyroid metastasis of CRC without any other clinically detectable metastases, including examples of thyroid metastasis of CRC occurring before clinically detectable lung metastasis [7]. Given these findings, the vertebral venous system has been proposed as a medium for metastatic spread -a route fully independent of entrance to the thoracic or abdominal cavities that completely bypasses the portal vein, pulmonary vein, and vena cava [9].…”

Curious Residents of the Thyroid Gland: Two Case Reports of Colorectal Carcinoma Metastasis by Fine-Needle Aspiration Diagnosis

“…The most fre- quent metastases to the thyroid originate in the kidney, lung or breast [2,3]. Metastases of colorectal adenocarcinoma are rare, accounting for less than 4% of thyroid metastases, with only 52 cases published so far [4,[6][7][8]. Solitary metastases of colorectal cancer with no other manifestation of disseminated cancer disease are exceedingly rare [7,8].…”

“…In some clinical series, metastasis to the thyroid appears to occur in abnormal glands, affected either by thyroiditis, adenomatous nodules or primary neoplasms [6,7]. According to the Campbell criteria, tumour-to-tumour metastasis requires more than one primary malignant tumour, the recipient tumour must be a true neoplasm and the donor malignancy must be a true metastasis [5,10,13].…”