Metastatic site discriminates survival benefit of primary tumor surgery for differentiated thyroid cancer with distant metastases

Abstract

The role of primary tumor surgery in the management of differentiated thyroid cancer (DTC) with distant metastases (DM) remains controversial. We aimed to explore the survival benefit of primary tumor surgery in patients with different metastatic sites. A retrospective cohort study based on the SEER database was conducted to identify DTC patients with DM diagnosed between 2010 and 2016. Patients were divided into following 2 groups: surgery and non-surgery group. Propensity score weighting was employed to balance clinicopathologic factors between the 2 groups. Of 3537 DTC patients with DM, 956 (66.0%) patients underwent primary tumor surgery while 493 (34.0%) patients did not. There were 798 all-cause deaths and 704 DTC-specific deaths over a median follow-up of 22 months. The weighted 3-year overall survival (OS) for the surgery group was 55.2%, compared to 27.8% ( P < .001) for the non-surgery group. The magnitude of the survival difference of surgery was significantly correlated with metastatic sites ( P interaction <.001). Significant survival improvements in surgery group compared with non-surgery group were observed in patients with lung-only metastasis (adjusted HR = 0.45, P < .001), bone-only metastasis (adjusted HR = 0.40, P < .001), and liver-only metastasis (adjusted HR = 0.27, P < .001), whereas no survival improvement of surgery was found for patients with brain-only metastasis (adjusted HR = 0.57, P = .059) or multiply organ distant metastases (adjusted HR = 0.81, P = .099). The survival benefit from primary tumor surgery for DTC patients with DM varies by metastatic sites. Decisions for primary tumor surgery of DTC patients with DM should be tailored according to metastatic sites.

Site-Specific Metastasis and Survival in Papillary Thyroid Cancer: The Importance of Brain and Multi-Organ Disease

“…However, liver (19.5%) and brain (7.9%) metastases were double the prevalence found in the current data of the SEER 9 registry and exhibited less frequency of multiple organ metastases (19%), as was reported in [ 27 ]. Ding et al used the SEER 18 registry (2010–2016) which covered both papillary and follicular TC patients from 18 geographical regions in the United States [ 27 ]. In contrast to our findings, the study of Chen et al [ 19 ] showed higher frequency of brain metastasis than liver.…”

“…Borschitz and his colleagues [ 26 ] revealed lung and bone to be the preferential sites for thyroid cancer metastasis. Similarly, the article published by Ding et al [ 27 ] reported the lungs as the most common site of distant metastasis in differentiated thyroid cancer, representing 47.7% of the population, followed by bone metastasis (24.9%). However, liver (19.5%) and brain (7.9%) metastases were double the prevalence found in the current data of the SEER 9 registry and exhibited less frequency of multiple organ metastases (19%), as was reported in [ 27 ].…”

“…Similarly, the article published by Ding et al [ 27 ] reported the lungs as the most common site of distant metastasis in differentiated thyroid cancer, representing 47.7% of the population, followed by bone metastasis (24.9%). However, liver (19.5%) and brain (7.9%) metastases were double the prevalence found in the current data of the SEER 9 registry and exhibited less frequency of multiple organ metastases (19%), as was reported in [ 27 ]. Ding et al used the SEER 18 registry (2010–2016) which covered both papillary and follicular TC patients from 18 geographical regions in the United States [ 27 ].…”

“…Consistent with our results, Wang et al [ 13 ] reported that the 5-year survival rate in patients with metastasis limited to one organ was 77.6%, while that in patients who develop second organ involvement was as low as 15.3%. Ding et al [ 27 ] demonstrated that the 3-year thyroid cancer-specific survival rate of bone metastasis from DTC was 50.4%, lung metastasis was 45.9%, liver metastasis was 40.9%, and brain metastasis was 28.7%. However, Sampson et al [ 25 ] reported the 3-year survival of single organ metastatic patients to be 77% in the presence of lung metastasis, significantly higher than bone metastasis (56%).…”

“…Surveillance imaging of the head during perioperative management or follow-up for PTC patients is not routinely considered unless there is clinical suspicion following neurological symptoms [ 34 , 39 ]. A significant survival advantage for definitive local primary tumor surgery was observed in DTC patients with single- or multi-organ metastasis, except for patients with only brain metastasis where surgery produced no survival benefit over non-operative management [ 27 ]. In addition to surgery, radiotherapy or radioactive iodine (RAI) therapy have been widely adopted to treat DTC patients with distant metastases.…”