Table 1 Demographic, clinical, and treatment characteristics of synchronous and metachronous patients with colorectal cancer liver metastases who underwent surgical resection, SEER-Medicare, 1991–2003

From: Predictors of survival after hepatic resection among patients with colorectal liver metastasis

Characteristic Metachronous CLM Synchronous CLM All CLM
Total 514 409 923
Demographic characteristics
 Age (years)    
65–69 178 (35%) 122 (30%) 300 (32%)
70–74 193 (38%) 134 (33%) 327 (35%)
75–79 106 (21%) 81 (20%) 187 (20%)
80+ 37 (7%) 72 (18%) 109 (12%)
 Race
White 441 (86%) 361 (88%) 802 (87%)
Black 25 (5%) 26 (6%) 51 (6%)
Other 48 (9%) 22 (5%) 70 (8%)
 Sex    
Female 291 (56%) 209 (51%) 500 (54%)
Male 223 (44%) 200 (49%) 423 (46%)
 Socioeconomic status    
1st quintile 99 (19%) 71 (17%) 170 (18%)
2nd quintile 96 (18%) 74 (18%) 170 (18%)
3rd quintile 108 (21%) 83 (20%) 191 (21%)
4th quintile 107 (21%) 96 (23%) 203 (22%)
5th quintile 104 (19%) 85 (21%) 189 (21%)
 Marital status    
Unmarried 136 (26%) 139 (34%) 275 (30%)
Married 362 (70%) 262 (64%) 624 (68%)
Unknown 16 (3%) 8 (2%) 24 (3%)
 Area of residence    
Metropolitan 467 (91%) 376 (92%) 843 (91%)
Rural 47 (9%) 33 (8%) 80 (9%)
 Year of diagnosis of CLM    
1991–1993 40 (8%) 64 (16%) 104 (11%)
1994–1996 96 (19%) 84 (21%) 180 (20%)
1997–1999 111 (21%) 89 (22%) 200 (22%)
2000–2003 267 (51%) 172 (42%) 439 (47%)
Clinical characteristics
 Site of primary tumour    
Rectal 146 (28%) 103 (25%) 249 (27%)
Colon 368 (72%) 306 (75%) 674 (73%)
 Stage of primary colorectal cancer    
I 71 (14%)   71 (7%)
II 162 (32%)   162 (18%)
III 281 (55%)   281 30%)
IV   409 (100%) 409 (44%)
 Number of positive lymph nodes    
0 210 (41%) 117 (27%) 327 (35%)
1–3 175 (34%) 153 (37%) 328 (36%)
4 95 (19%) 96 (23%) 191 (21%)
Unknown 34 (7%) 43 (11%) 77 (8%)
 Tumour grade of primary colorectal cancer    
Well/moderately differentiated 406 (79%) 311 (76%) 717 (78%)
Poorly/undifferentiated 90 (18%) 85 (21%) 175 (19%)
Unknown 18 (3%) 13 (3%) 31 (3%)
 Comorbidity score    
0 315 (61%) 272 (67%) 587 (64%)
1 143 (28%) 97 (24%) 240 (26%)
>1 56 (11%) 40 (9%) 96 (10%)
Treatment characteristics
 Care in a teaching hospital    
No 34 (7%) 37 (9%) 71 (8%)
Yes 476 (93%) 365 (89%) 841 (91%)
Unknown <5 (1%) <10 (2%) 11 (1%)
 Care in NCI-designated cancer centre    
No 329 (64%) 283 (76%) 612 (66%)
Yes 185 (36%) 126 (31%) 311 (34%)
 Hospital procedure volume    
Low (1–8) 125 (24%) 164 (40%) 289 (31%)
Medium (9–29) 147 (29%) 120 (29%) 267 (30%)
High (>29) 242 (47%) 125 (31%) 367 (40%)
 Adjuvant chemotherapy for primary cancer    
Yes 182 (35%) NA NA
No 332 (65%)   
 Adjuvant chemotherapy after resection    
Combined FUdR and 5FU therapy 40 (8%) 34 (8%) 74 (8%)
5FU-based therapy only 187 (36%) 256 (62%) 443 (48%)
No chemotherapy 287 (56%) 122 (30%) 409 (44%)
  1. CLM=colorectal cancer liver metastasis; 5FU=5-fluorouracil; FUdR=floxuridine; NA=not applicable.