Calcitonin-negative neuroendocrine tumor of the thyroid with metastasis to liver-rare presentation of an unusual tumor: A case report and review of literature

Table 1 Characteristics of calcitonin-negative neuroendocrine tumors of the thyroid

Patient	Ref.	Sex/age	Tumor size in cm	Immunohistochemistry					Metastasis
				CGA	SYN	TTF-1	CEA	TG
1	Redding et al[8], 2000	F/31	4.5	NA	+	NA	NA	-	NA
2	Giovanella et al[9], 2008	F/43	NA	-	NA	NA	+	NA	NO
3	Wang et al[10], 2008	M/68	6.5	NA	+	+	-	NA	Lymph nodes
4	Dora et al[11], 2008	M/43	1.7	+	NA	NA	+	-	Lymph nodes
5	Alapat et al[12], 2011	F/16	3.0	+	NA	NA	+	NA	NO
6	Chernyavsky et al[13], 2011	F/40	1.5	+	+	NA	NA	+	NO
7	Nakazawa et al[14], 2014	M/76	6.0	+	-	-	-	NA	NO
8	Mussazhanova et al[15], 2014	M/64	5.4	+	+	-	-	+	NO
9	Kim et al[16], 2014	M/34	0.6	+	+	+	-	+	NO
10	Ismi et al[17], 2014	M/57	15.0	+	+	-	-	NA	Lung, peritoneum
11	Brutsaert et al[18], 2015	F/39	2.6	+	NA	+	-	NA	NO
12	Kasajima et al[19], 2016	M/48	2.8	+	+	+	+	NA	NO
13	Samà et al[20], 2016	M/60	3.8	+	NA	NA	+	NA	NO
14	Samà et al[20], 2016	M/53	1.2	-	NA	NA	-	NA	NO
15	Samà et al[20], 2016	M/62	4.5	+	NA	NA	-	NA	NO
16	Parmer et al[21], 2017	F/74	1.6	+	+	+	+	NA	NA
17	Sukpanich et al[22], 2019	F/60	3.8	+	+	+	NA	+	NO

CGA: Chromogranin; SYN: Synuclein; TTF-1: Thyroid transcription factor 1; CEA: Carcinoembryonic antigen; TG: Thyroglobulin; M: Male; F: Female; -: Negative; +: Positive; NA: Not available.