Table 2.
LOH at key genetic loci in PAs according to location and outcome
| Genetic locus | Location | Any LOH (%) | No. of adverse outcomes/total (%) | P |
|---|---|---|---|---|
| 1p | Cerebellum | Yes (56.9) | 4/33 (12.1) | 0.7152 |
| No (43.1) | 4/25 (16.0) | |||
| Cerebrum | Yes (60.0) | 5/12 (41.7) | 0.3246 | |
| No (40.0) | 1/8 (12.5) | |||
| MB/BS/SC | Yes (80.0) | 9/16 (56.3) | 1.0000 | |
| No (20.0) | 2/4 (50.0) | |||
| 19q | Cerebellum | Yes (35.1) | 3/20 (15.0) | 1.0000 |
| No (64.9) | 5/37 (13.5) | |||
| Cerebrum | Yes (27.8) | 2/5 (40.0) | 0.5827 | |
| No (72.2) | 3/13 (23.1) | |||
| MB/BS/SC | Yes (63.2) | 6/12 (50.0) | 0.6332 | |
| No (36.8) | 5/7 (71.4) | |||
| 9p21 (CDKN2A/p16) | Cerebellum | Yes (33.9) | 4/19 (21.1) | 0.1652 |
| No (66.1) | 2/37 (5.4) | |||
| Cerebrum | Yes (38.9) | 2/7 (28.6) | 1.0000 | |
| No (61.1) | 4/11 (36.4) | |||
| MB/BS/SC | Yes (31.6) | 2/6 (33.3) | 0.3189 | |
| No (68.4) | 9/13 (69.2) | |||
| 10q23 (PTEN) | Cerebellum | Yes (50.0) | 2/23 (50.0) | 1.0000 |
| No (50.0) | 2/23 (50.0) | |||
| Cerebrum | Yes (57.1) | 3/8 (37.5) | 0.2088 | |
| No (42.9) | 0/6 (0.0) | |||
| MB/BS/SC | Yes (50.0) | 5/7 (71.4) | 1.0000 | |
| No (50.0) | 4/7 (57.1) | |||
| 17p13 (TP53) | Cerebellum | Yes (33.3) | 5/18 (27.8) | 0.0344* |
| No (66.7) | 2/36 (5.6) | |||
| Cerebrum | Yes (31.3) | 1/5 (20.0) | 1.0000 | |
| No (68.8) | 3/11 (27.3) | |||
| MB/BS/SC | Yes (41.2) | 5/7 (71.4) | 0.6221 | |
| No (58.8) | 5/10 (50.0) |
PAs with outcome data were assessed for loss of heterozygosity (LOH) via PCR (see “Methods”) at genetic loci known to be of biological and/or prognostic significance in higher-grade pediatric and adult gliomas. LOH at 17p13, containing the TP53 gene, showed significant correlation with adverse outcome via Fisher’s exact test, but only in cerebellar tumors (this table includes only the 118 PAs with outcome data; in some cases, DNA was inadequate for assessment in one or more loci)
MB/BS/SC midbrain, brainstem, and spinal cord
*
P < 0.05 via Kruskal–Wallis