Hippocampal dosimetry correlates with the change in neurocognitive function after hippocampal sparing during whole brain radiotherapy: a prospective study

Table 3 Correlation of hippocampal dosimetry with the status of NCF change in verbal memory after HS-WBRT

Dosimetric parameters	Dosimetric cut-off points	NCF Preservation N (%)	No preservation	p value
Bilateral hippocampi as a composite structure
Maximum	≤12.6 Gy	10(83.3 %)	2(16.7 %)	0.004*
Maximum	>12.6 Gy	3(25.0 %)	9(75.0 %)	0.004*
D_10%	≤8.81 Gy	9(75.0 %)	3(25.0 %)	0.041*
D_10%	>8.81 Gy	4(33.3 %)	8(66.7 %)	0.041*
D_20%	≤8.26 Gy	8(66.7 %)	4(33.3 %)	0.219
D_20%	>8.26 Gy	5(41.7 %)	7(58.3 %)	0.219
D_30%	≤7.95 Gy	8(66.7 %)	4(33.3 %)	0.219
D_30%	>7.95 Gy	5(41.7 %)	7(58.3 %)	0.219
D_40%	≤7.68 Gy	8(66.7 %)	4(33.3 %)	0.219
D_40%	>7.68 Gy	5(41.7 %)	7(58.3 %)	0.219
D_50%	≤7.45 Gy	9(75.0 %)	3(25.0 %)	0.041*
D_50%	>7.45 Gy	4(33.3 %)	8(66.7 %)	0.041*
D_80%	≤6.80 Gy	9(75.0 %)	3(25.0 %)	0.041*
D_80%	>6.80 Gy	4(33.3 %)	8(66.7 %)	0.041*
D_100%	≤5.83 Gy	9(75.0 %)	3(25.0 %)	0.041*
D_100%	>5.83 Gy	4(33.3 %)	8(66.7 %)	0.041*
Left hippocampus
Maximum	≤12.41 Gy	10(83.3 %)	2(16.7 %)	0.004*
Maximum	>12.41 Gy	3(25.0 %)	9(75.0 %)	0.004*
D_10%	≤8.75 Gy	9(75.0 %)	3(25.0 %)	0.041*
D_10%	>8.75 Gy	4(33.3 %)	8(66.7 %)	0.041*
D_20%	≤8.22 Gy	8(66.7 %)	4(33.3 %)	0.219
D_20%	>8.22 Gy	5(41.7 %)	7(58.3 %)	0.219
D_30%	≤7.94 Gy	8(66.7 %)	4(33.3 %)	0.219
D_30%	>7.94 Gy	5(41.7 %)	7(58.3 %)	0.219
D_40%	≤7.70 Gy	9(75.0 %)	3(25.0 %)	0.041*
D_40%	>7.70 Gy	4(33.3 %)	8(66.7 %)	0.041*
D_50%	≤7.48 Gy	9(75.0 %)	3(25.0 %)	0.041*
D_50%	>7.48 Gy	4(33.3 %)	8(66.7 %)	0.041*
D_80%	≤6.73 Gy	9(75.0 %)	3(25.0 %)	0.041*
D_80%	>6.73 Gy	4(33.3 %)	8(66.7 %)	0.041*
D_100%	≤5.73 Gy	8(66.7 %)	4(33.3 %)	0.219
D_100%	>5.73 Gy	5(41.7 %)	7(58.3 %)

The status of neurocognitive change shown here is according to patients’ performance on the immediate recall of Wechsler Memory Scale-III Word Lists. The association between hippocampal dosimetry and the status of NCF change (preservation or not) in verbal memory 4 months after the HS-WBRT course was evaluated by using chi-square test for the 24 patients in whom post-treatment NCF assessment was available
The N (%) is listed to stand for the number of patients and its corresponding percentage
* indicates that statistical significance is noted

ISSN: 1748-717X