The significance of surveillance imaging in children with Ewing sarcoma and osteosarcoma

Figures & data

Figure 1. CONSORT diagram. A total of 69 patients with histologically proven Ewing sarcoma (n = 34) or osteosarcoma (n = 35) were included. The final data set for analysis included 52 patients, 25 Ewing sarcomas and 27 osteosarcomas.

Table 1. Disease characteristics, treatment and follow up of the 25 patients with Ewing sarcoma (EWS) and the 27 patients with osteosarcoma (OS).

	EWS [%]	OS [%]
Tumor location
Face or skull	2 [8]	1 [4]
Chest region	4 [16]	0
Spine	3 [12]	0
Upper extremities	3 [12]	1 |4]
Pelvic region	5 [20]	1 [4]
Lower extremities	8 [32]	24 [89]
Metastases present at the time of diagnosis.	6 [24]	3 [11]
Type of surgery (primary site)
Local excision	14 [56]	0
Amputation	4 [16]	7 [26]
Rotational plastic	0	5 [18.5]
Biological reconstruction	3 [12]	4 [15]
Internal prosthesis	1 [4]	10 [37]
None	3 [12]	1 [4]
Radiation dose (Gy)
Number of patients	10	1
Median [range]	55 [45-72]	72
FU without relapse [months]
<12	3 [12]	4 [15]
12–24	4 [16]	4 [15]
>24	18 [72]	19 [70]
Median FU time without relapse [months]	15	13
Recurrence pattern
Local relapse	3	1
Lung	1	4
No relapse	21	22

Table 2. Number of scans suspect and not suspect for malignancy (column), and if the malignancy were confirmed or refuted (row).

	EWS			OS
	Malignancy confirmed	Malignancy refuted	Total	Malignancy confirmed	Malignancy refuted	Total
FU-images suspect for malignancy	4 = TP	5 = FP	9	5 = TP	4 = FP	9
FU-images not suspect for malignancy	0 = FN	599 = TN	599	0 = FN	663 = TN	663
Total	4	604	608	5	667	671
Sensitivity (TP/total number of confirmed) = 1 Specificity (TN/total number of refuted) = 0.99 PPV (TP/total number of suspect for malignancy) = 0.44				Sensitivity (TP/total number of confirmed) = 1 Specificity (TN/total number of refuted) = 0.99 PPV (TP/total number of suspect for malignancy) = 0.5

True positive (TP), True negative (TN), False positive (FP) and False negative (FN).

Table 3. Abnormalities identified through imaging and the subsequent clinical decisions.

	EWS	OS
Malignancy suspected	9	9
Further investigation:	9	9
Biopsy	5	1
Change of follow up protocol	3	8
Change of imaging modality	4	6
Observation only	0	0
Benign condition suspected	32	11
Further investigation:	9	2
Biopsy	0	0
Change of follow up protocol	6	2
Change of imaging modality	3	1
Observation only	23	9
Unclear	32	21
Further investigation:	27	20
Biopsy	1	5
Change of follow up protocol	25	15
Change of picture modality	16	7
Observation only	5	1

Overall counts.

Table 4. Location, and type of abnormalities found in other locations.

Patient number	Primary location of tumor (side)	Location of abnormality	What abnormality
14 (EWS)	Calcaneus (left)	Proximal tibia (left)	Fissure
14 (EWS)	Calcaneus (left)	Distal femur (left)	Fracture due to trauma
17 (EWS)	Proximal tibia (left)	Distal tibia (left)	Aseptic osteomyelitis
20 (EWS)	3rd metatarsal (right)	Trochlea tali (left)	Edema
21 (EWS)	Distal tibia (left)	Proximal tibia (left)	Edema
42 (EWS)	Distal radius (right)	Distal tibia (right)	Inflammation
42 (EWS)	Distal radius (right)	Distal tibia (right)	Reactive changes
69 (EWS)	Os pubis	Acetabulum (left)	Change of bone-structure
69 (EWS)	Os pubis	Collum femoris (left)	Epifysiolysis
31 (OS)	Proximal tibia (left)	Ilium (right)	Stool overlap.
50 (OS)	Calcaneus (right)	Elbow (right)	Reactive lymph node
55 (OS)	Distal femur (left)	Calcaneus (left).	Osteoporosis