Table 1.
Levels of evidence of all included studies and demographic data
| References | Type | Level of evidence | No. of patients | Sex | Age | Primary tumour | Comorbidities | |
|---|---|---|---|---|---|---|---|---|
| 1 | Gerszten et al. [32] | Prospective cohort study | II | 393 pt/500 lesions, 103 sacral lesions | 251F, 142M | 56 (18–85) | RCC 93, breast 83, lung 80, melanoma 38, colon 32, sarcoma 26, prostate 24, MM 18, unknown 14, squamous cell 12, thyroid 11, other 69 | N/A |
| 2 | Takayuki Akasu et al. [33] | Prospective case series | III | 44 | 35M, 9F | 55 (32–73) | Recurrent rectal ca | N/A |
| 3 | Nader et al. [28] | Literature review/case series | III | 19 | N/A | N/A | RCC 13, breast ca 2, melanoma 1, M. myeloma 1, colon ca 1, liposarcoma 1 | N/A |
| 4 | Kollender et al. [2] | Retrospective case series | IV | 14 pt/5 pt sacral metastases | 7M, 7F | 42 (14–74) | 2 RCC, 2 MC, 1 colon ca | N/A |
| 5 | Ozdemir et al. [10] | Retrospective case series | IV | 65 pt, (34 pt sacral mets) | 25F, 21M | 49 (12–83) | 9 breast, 7 MM, 4 prostate, 3 lung, 3 colon, 2 leiomyosarcoma, 2 lymphoma, 1 ovary, 1RCC, 1 thyroid, 1 larynx | N/A |
| 6 | Dozois et al. [34] | Retrospective case series | IV | 9 | 7M, 2F | 63 (38–78) | Recurrent rectal ca | All had previous resection surgery |
| 7 | Fujibayashi et al. [35] | Retrospective case series | IV | 5 | 4M, 1F | 47, 8 (29–77) | 2 lung, 2 renal, 1 paraganglioma | N/A |
| 8 | Zhang et al. [36] | Case report | IV | 2 | 1M, 1F | 62M, 38F | 62M lymphoma, 38F lung ca | 62M skeletal mets, 38F None |
| 9 | Lee et al. [37] | Case report | IV | 1 | F | 51 | Meningioma | Tumour excision from R frontal lobe |
| 10 | Toro et al. [38] | Case report | IV | 1 | M | 65 | HCC | Hep C(+) segmentectomy child-pugh st A |
| 11 | Uemura et al. [39] | Case report | IV | 1 | M | 76 | HCC | N/A |
| 12 | Kakutani et al. [40] | Case report | IV | 1 | M | 52 | Melanoma | Lung mets |
| 13 | Nebreda et al. [41] | Case report | IV | 1 | F | 48 | Small cell lung ca | N/A |
| 14 | Menegaz et al. [42] | Case report | IV | 1 | F | 45 | Choriocarcinoma | Previous uterine curettage for hydatidiform mole |
| 15 | Turgut et al. [43] | Case report | IV | 1 | M | 63 | Mercel cell ca (skin) | NO |
| 16 | Albareda et al. [44] | Case report | IV | 1 | F | 62 | Endometrial adeno ca | Surgery for endometrial ca |
HCC hepatocellular ca, RCC renal cell ca, MM multiple myeloma, PNET primitive neuroectodermal tumour, MC metastatic carcinoma