Table 2. Clinical characteristics of patients with secondary metastases (n=46) and without SDD (n=224).

	Patients with SDD		Patients without SDD
Characteristics	n	%	n	%
Gender
Male	27	58.7	115	51.3
Female	19	41.3	109	48.7
Median age at primary diagnosis	10.2 years (0.1–19.1 years)		9.2 years (0.1–21 years)
Primary tumour site
Cerebral hemispheres	14	30.4	53	23.7
Pons/brainstem	14	30.4	106	47.3
Thalamus/basal ganglia	6	13.0	24	10.7
Cerebellum	5	10.9	5	2.2
Ventricles	2	4.3	6	2.7
Medulla	1	2.2	1	0.4
Pineal region	1	2.2	1	0.4
Hypothalamus	0	0	2	0.9
Spinal cord	1	2.2	4	1.8
Gliomatosis cerebri	2	4.3	11	4.9
Brain NOS	0	0	11	4.9
Diagnosis
Glioblastoma multiforme grade IV	20	43.5	76	33.9
Giant cell glioblastoma grade IV	1	2.2	2	0.9
Anaplastic astrocytoma grade III	17	37.0	63	28.1
Oligoastrocytoma/-dendroglioma grade III	0	0	5	22.3
Gliosarcoma grade IV	0	0	2	0.9
Astroblastoma/xantoastrocytoma grade III	0	0	3	1.3
Astrocytoma WHO grade I/II (DIPG)	2	4.3	16	7.1
DIPG, only radiologic diagnosis	6	13.0	57	25.4
Spinal MRI at primary diagnosis	10/39*	25.6	nd
CSF positive at primary diagnosis	2/11*	18.2	3/33	9.1
Resection of the primary tumour (n=222)
Complete resection	7	15.2	33	14.9
Subtotal resection (⩾95% of the tumor removed)	9	19.6	24	10.8
Partial resection (< 95% of the tumor removed)	9	19.6	39	17.7
Biopsy	15	32.6	75	33.8
No surgery	6	13.0	51	22.9
Irradiation of the primary tumour (n=221)
Yes	45	97.8	201	90.9
No	1	2.2	20	9.1
Simultaneous radiochemotherapy of the primary tumor (n=220)
Yes	21	45.7	95	43.2
No	25	54.3	125	56.8
Chemotherapy of the primary tumour (n=221)
Yes	42	91.3	204	92.3
No	4	8.7	17	7.7

MRI=magnet resonance imaging; CSF=cerebrospinal fluid; DIPG=diffuse intrinsic pontine glioma; NOS=no other specification.

^*Data were available for only 39 or 11 patients.