Correction to: PD-1 axis expression in musculoskeletal tumors and antitumor effect of nivolumab in osteosarcoma model of humanized mouse.

The original article [1] contained an error in Table 1 whereby the 'Positive' column in the 'PD-L1' Tumor type group of columns was mistakenly included at the beginning of the 'PD-L2' Tumor type group of columns.

Erratum

The original article [1] contained an error in Table 1 whereby the ‘Positive’ column in the ‘PD-L1’ Tumor type group of columns was mistakenly included at the beginning of the ‘PD-L2’ Tumor type group of columns.

Table 1

Expression of PD-L1, PD-L2, and PD-1 in musculoskeletal tumors

Tumor	N	PD-L1N (%)					PD-L2N (%)					PD-1N (%)
		0	1+	2+	3+	Positive	0	1+	2+	3+	Positive	0	1+	2+	3+	Positive
Musculoskeletal tumor	234	179	35	10	10	55 (23.5%)	168	49	8	9	66 (28.2%)	185	37	5	7	49 (20.9%)
Giant cell tumor	14	4	1	2	7	10 (71.4%)	7	1	1	5	7 (50.0%)	6	1	2	5	8 (57.1%)
Osteosarcoma	62	40	17	3	2	22 (35.5%)	36	21	3	2	26 (41.9%)	45	15	1	1	17 (27.4%)
Synovial sarcoma	127	107	16	3	1	20 (15.7%)	101	22	2	2	26 (20.5%)	103	21	2	1	24 (18.9%)
Chondrosarcoma	31	28	1	2	0	3 (9.7%)	24	5	2	0	7 (22.6%)	31	0	0	0	0
Conventional chondrosarcoma	27	27	0	0	0	0	21	4	2	0	6 (22.2%)	27	0	0	0	0
Dedifferentiated chondrosarcoma	4	1	1	2	0	3 (75.0%)	3	1	0	0	1 (25.0%)	4	0	0	0	0

This error has now been corrected. Furthermore, this error was not the fault of the authors, and was instead mistakenly carried forward by the production team that handled this article.