Table 2 Statistical analysis of differences in treatment policies stratified by type of institution or position

From: Management of multiple brain metastases: a patterns of care survey within the German Society for Radiation Oncology

Question and answers All answers Academic centers (University Hospitals) (A) Non-academic centers (B) Head/deputy head of department (A) Others (B) High-volume centers < 50 pts/year (A) Low-volume centers > 50 pts/year (B)
Max total no. = 171 n (%) n (%) n (%) n (%) n (%) n (%) n (%)
p-value* p-value* p-value*
Do you use a prognostic score before treatment of brain metastases?
 Yes 64 (37.4) 20 (54.1) 44 (32.8) 15 (44.1) 49 (35.8) 34 (44.2) 30 (31.9)
 No 107 (62.6) 17 (45.9) 90 (67.2) 19 (55.9) 88 (64.2) 43 (55.8) 64 (68.1)
   0.018 0.368 0.100
Does the prognostic score influence your decision regarding therapeutic options?
 Yes 62 (36.8) 20 (54.1) 43 (32.1) 14 (41.2) 49 (35.8) 32 (41.6) 31 (33.0)
 No 108 (63.2) 17 (45.9) 91 (67.9) 20 (58.8) 88 (64.2) 45 (58.4) 63 (667.0)
   0.014 0.558 0.247
Is the treatment recommendation for cerebral irradiation made in an interdisciplinary tumor board?
 Yes, always 53 (31.0) 21 (56.8) 32 (23.9) 12 (35.3) 41 (29.9) 32 (41.6) 21 (22.3)
 Yes, in most cases (> 50%) 105 (61.4) 16 (43.2) 89 (66.4) 19 (55.9) 86 (62.8) 41 (53.2) 64 (68.1)
 No, not regularly 13 (7.6) 0 (0) 13 (9.7) 3 (8.8) 10 (7.3) 4 (5.2) 9 (9.6)
    < 0.001 0.761 0.022
Regarding RPA-Score: At which score would you perform a stereotactic irradiation?
 No use of RPA 106 (62.0) 17 (45.9) 89 (66.4) 19 (55.9) 87 (63.5) 44 (57.1) 62 (66.0)
 Only RPA 1 12 (7.0) 5 (13.5) 7 (5.2) 4 (11.8) 8 (5.8) 5 (6.5) 7 (7.4)
 RPA 1 and 2 41 (24.0) 13 (35.1) 28 (20.9) 6 (17.6) 35 (25.5) 26 (33.8) 15 (16.0)
 RPA 1–3 12 (7.0) 2 (5.4) 10 (7.5) 5 (14.7) 7 (5.1) 2 (2.6) 10 (10.6)
   0.059 0.116 0.018
Regarding GPA-Score: At which score would you perform a stereotactic irradiation?
 No use of GPA 109 (63.7) 17 (45.9( 92 (68.7) 20 (58.8) 89 (65.0) 46 (59.7) 63 (67.0)
 GPA > 2.5 39 (22.8) 14 (37.8) 25 (18.7) 8 (23.5) 31 (22.6) 22 (28.6) 17 (18.1)
 GPA < 2.5 and > 2.5 23 (13.5) 6 (16.2) 17 (12.7) 6 (17.6) 17 (12.4) 9 (11.7) 14 (14.9)
   0.026 0.695 0.257
What is the main treatment choice in ≥ 75% of cases in patients presenting with 4–10 brain metastases and a GPA < 2.5?
 SRS or fSRT 32 (18.7) 16 (43.2) 16 (11.9) 9 (26.5) 23 (16.8) 22 (28.6) 10 (1.6)
 WBRT ± boost or HCS 139 (81.3) 21 (56.8) 118 (88.1) 25 (73.5) 114 (83.2) 55 (71.4) 84 (89.4)
    < 0.001 0.195 0.003
What is the main treatment choice in ≥ 75% of cases in patients presenting with 4–10 brain metastases and a GPA > 2.5?
 SRS or fSRT 53 (31.0) 21 (56.8) 32 (23.9) 13 (38.2) 40 (29.2) 32 (41.6) 21 (22.3)
 WBRT ± boost or HCS 118 (69.0) 16 (43.2) 102 (76.1) 21 (61.8) 97 (70.8) 45 (58.4) 73 (77.7)
    < 0.001 0.308 0.007
If you perform Whole-Brain-Irradiation for 4 to 10 brain metastases. do you choose a hippocampal avoidance technique?
 All cases 21 (12.6) 6 (16.2) 15 (11.5) 1 (3.1) 20 (14.8) 12 (15.6) 9 (10.0)
 Not regularly, only individual cases 72 (43.1) 19 (51.4) 53 (40.8) 15 (46.9) 57 (42.2) 36 (50.6) 33 (36.7)
 None 74 (44.3) 12 (32.4) 62 (47.7) 16 (50.0) 58 (43.0) 26 (33.8) 48 (53.3)
   0.251 0.199 0.039
When do you schedule first clinical evaluation after radiotherapy?
 Within 1 month after RT 33 (26.0) 11 (33.3) 22 (23.4) 8 (34.8) 25 (24.0) 11 (17.5) 22 (34.4)
 Within second months after RT 75 (59.1) 17 (51.5) 58 (61.7) 12 (52.2) 63 (60.6) 40 (63.5) 35 (54.7)
 Within third month after RT 18 (14.2) 5 (15.2) 13 (13.8) 3 (13.0) 15 (14.4) 11 (17.5) 7 (10.9)
 Within fourth month after RT 1 (0.8) 0 (0.0) 1 (1.1) 0 (0.0) 1 (1.0) 1 (1.6) 0 (0.0)
   0.629 0.727 0.118
When do you schedule first diagnostic evaluation after radiotherapy?
 Within one month after RT 5 (3.9) 2 (6.1) 3 (3.1) 1 (4.3) 4 (3.8) 3 (4.7) 2 (3.1)
 Within second months after RT 48 (37.2) 13 (36.5) 35 (36.5) 9 (39.1) 39 (36.8) 22 (34.4) 26 (40.0)
 Within third month after RT 75 (58.1) 18 (54.5) 57 (59.4) 13 (53.5) 62 (58.5) 38 (59.4) 37 (56.9)
 Within fourth month after RT 1 (0.8) 0 (0.0) 1 (1.0) 0 (0.0) 1 (0.9) 1 (1.6) 0 (0.0)
   0.790 0.965 0.673
When do you switch to longer follow-up intervals after radiotherapy (with stable findings)?
 Already within 1 year 5 (4.3) 0 (0.0) 5 (6.1) 0 (0.0) 5 (5.2) 4 (6.6) 1 (1.8)
 After at least 1 year 44 (37.6) 3 (8.6) 41 (50.0) 10 (47.6) 34 (35.4) 16 (26.2) 28 (50.0)
 After at least 2 years 61 (52.1) 27 (77.1) 34 (41.5) 8 (38.1) 53 (55.2) 37 (60.7) 24 (42.9)
 After at least 3 years 7 (6.0) 5 (14.3) 2 (2.4) 3 (14.3) 4 (4.2) 4 (6.6) 3 (5.4)
    < 0.001 0.128 0.051
What imaging do you use when radiation necrosis is suspected? (multiple answers)
 T1 ± Gad, FLAIR 84 (71.8) 25 (69.4) 59 (72.8) 19 (79.2) 65 (69.9) 42 (77.8) 42 (66.7)
 Diffusion-weighted MR 62 (53.0) 20 (55.6) 42 (51.9) 15 (62.5) 47 (50.5) 24 (44.4) 38 (60.3)
 Dynamic MR sequences 24 (20.5) 10 (27.8) 14 (17.3) 7 (29.2) 17 (18.3) 10 (18.5) 14 (22.2)
 MR spectroscopy 30 (25.6) 12 (33.3) 18 (22.2) 5 (20.8) 25 (26.9) 12 (22.2) 18 (28.6)
 Amino-acid based PET examination 56 (47.9) 29 (80.6) 27 (33.3)   9 (37.5)   20 (37.0)
    < 0.001 0.421 0.068
Hypothetical patient scenario: 55 years old, 8 BM, primary tumor NSCLC, estimated survival > 6 months, therapeutic approach?
 SRS or fSRT 55 (33.1) 21 (56.8) 34 (26.4) 11 (34.4) 44 (32.8) 33 (44.0) 22 (24.2)
 WBRT approach 111 (66.9) 16 (43.2) 95 (73.6) 21 (65.6) 90 (67.2) 42 (56.0) 69 (75.8)
   0.001 0.868 0.007
Hypothetical patient scenario: 55 years old, 8 BM, primary tumor NSCLC, estimated survival < 6 months, therapeutic approach?
 SRS or fSRT 27 (16.4) 9 (24.3) 18 (14.2) 4 (12.5) 23 (17.4) 18 (24.0) 9 (10.1)
 WBRT approach 137 (83.6) 28 (75.7) 109 (85.8) 28 (87.5) 109 (82.6) 57 (76.0) 80 (89.9)
   0.143 0.500 0.017
Would your decision regarding the therapy sequence change if the tumor would show EGFR/ALK mutation?
 Proceed with upfront RT 98 (71.0) 25 (73.5) 73 (70.2) 20 (71.4) 78 (70.8) 48 (75.0) 50 (67.6)
 Delay RT for sole upfront TKI therapy 40 (29.0) 9 (26.5) 31 (29.8) 8 (28.6) 32 (29.1) 16 (25.0) 24 (32.4)
   0.139 0.957 0.921
Hypothetical patient scenario: 45 yo, 15 BM, primary tumor NSCLC, estimated survival > 6 months, therapeutic approach?
 SRS or fSRT 18 (10.9) 6 (16.7) 12 (9.3) 4 (12.9) 14 (10.4) 13 (17.3) 5 (5.6)
 WBRT approach 147 (89.1) 30 (83.3) 117 (90.7) 27 (87.1) 120 (89.6) 62 (82.7) 85 (94.4)
   0.210 0.693 0.016
Hypothetical patient scenario: 45 yo, 15 BM, primary tumor NSCLC, estimated survival < 6 months, therapeutic approach?
 SRS or fSRT 6 (3.7) 2 (5.6) 4 (3.2) 1 (3.2) 5 (3.8) 5 (6.8) 1 (1.1)
 WBRT approach 155 (96.3) 34 (94.4) 121 (96.8) 30 (96.8) 125 (96.2) 69 (93.2) 86 (98.9)
   0.511 0.870 0.061
Would your decision regarding the therapy sequence change if the tumor would show EGFR/ALK mutation?
 Proceed with upfront RT 98 (71.5) 26 (76.5) 72 (69.9) 19 (70.4) 79 (71.8) 51 (69.9) 47 (73.4)
 Delay RT for sole upfront TKI therapy 39 (28.5) 8 (23.5) 31 (30.1) 8 (29.6) 31 (28.2) 22 (30.1) 17 (26.6)
   0.462 0.881 0.644
  1. RT radiotherapy, RPA recursive partitioning analysis, GPA graded prognostic assesment, yo years old, NSCLC non-small-cell lung cancer, EGFR epidermal-growth-factor receptor, ALK anaplastic lymphoma kinase
  2. *p-value according to Chi-Square-Test