Table 1.
Clinical and laboratory characteristics of 580 patients with SM seen at the Mayo Clinic between 1968 and 2015
| Variables | All patients (N = 580) | ISM/SSM (n = 291) | Advanced SM (n = 289) | P | ASM (n = 85) | SM-AHN (n = 199) | MCL (n = 5) | P |
|---|---|---|---|---|---|---|---|---|
| Median age (range), y | 55 (18-88) | 48 (19-87) | 64 (18-88) | <.001 | 61 (32-86) | 65 (18-88) | 57 (45-74) | .08 |
| Age >60 y, n (%) | 235 (41) | 65 (22) | 170 (59) | <.001 | 44 (52) | 124 (62) | 2 (40) | .2 |
| Males, n (%) | 301 (52) | 127 (44) | 174 (60) | <.001 | 38 (45) | 132 (66) | 4 (80) | .002 |
| Hemoglobin, median (range), g/dL | 13.1 (5.1-17.4) | 13.9 (8.1-17.2) | 11.1 (5.1-17.4) | <.001 | 12.3 (5.1-17) | 10.8 (5.2-17.4) | 10.9 (9.5-11.5) | .03 |
| Anemia sex adjusted, n (%) | 236 (41) | 41 (14) | 195 (67) | <.001 | 44 (52) | 146 (73) | 5 (100) | <.001 |
| n eval = 574 | n eval = 285 | |||||||
| Leukocyte count, median (range), ×109/L | 7.1 (0.7-87.2) | 6.5 (1.6-22.2) | 8.3 (0.7-87.2) | <.001 | 7.3 (1.7-37.1) | 9 (0.7-87.2) | 4.5 (3.8-7) | .004 |
| n eval = 573 | n eval = 284 | |||||||
| Platelet count, median (range), ×109/L | 229 (2-1625) | 257.5 (39-563) | 157 (2-1625) | <.001 | 218.5 (19-570) | 134.5 (2-1625) | 145 (54-241) | <.001 |
| n eval = 567 | n eval = 280 | n eval = 287 | n eval = 84 | n eval = 198 | ||||
| Platelet count <150 × 109/L, n (%) | 149 (26) | 13 (5) | 136 (47) | <.001 | 23 (27) | 110 (56) | 3 (60) | <.001 |
| n eval = 567 | n eval = 280 | n eval = 287 | n eval = 84 | n eval = 198 | ||||
| Urticaria pigmentosa, n (%) | 234 (41) | 162 (56) | 72 (25) | <.001 | 32 (38) | 40 (20) | 0 (0) | .003 |
| n eval= 577 | n eval = 288 | |||||||
| Mast cell mediator symptoms, n (%) | 162 (46) | 106 (69) | 56 (29) | <.001 | 14 (27) | 40 (29) | 2 (50) | .6 |
| n eval = 349 | n eval = 153 | n eval = 196 | n eval = 52 | n eval = 140 | n eval = 4 | |||
| Serum tryptase <20; n (%) | 87 (22) | 62 (27) | 25 (14) | 5 (8) | 19 (17) | 1 (33) | ||
| Serum tryptase 20-200; n (%) | 266 (66) | 156 (68) | 110 (64) | 40 (68) | 69 (62) | 1 (33) | ||
| Serum tryptase >200; n (%) | 49 (12) | 11 (5) | 38 (22) | 14 (24) | 23 (21) | 1 (33) | ||
| n eval = 402 | n eval = 229 | n eval = 173 | n eval = 59 | n eval = 111 | n eval = 3 | |||
| BM mast cell <5%, n (%) | 31 (7) | 26 (12) | 5 (2) | 2 (3) | 3 (2) | 0 (0) | ||
| BM mast cell 5%-10%, n (%) | 211 (49) | 124 (56) | 87 (41) | 26 (38) | 61 (44) | 0 (0) | ||
| BM mast cell 11%-50%, n (%) | 144 (33) | 58 (26) | 86 (40) | 23 (34) | 63 (45) | 0 (0) | ||
| BM mast cell >50%, n (%) | 46 (11) | 12 (5) | 34 (16) | 17 (25) | 13 (9) | 4 (100) | ||
| n evaluable = 432 | n eval = 220 | n eval = 212 | n eval = 68 | n eval = 140 | n eval = 4 | |||
| Palpable hepatomegaly, n (%) | 119 (21) | 25 (9) | 94 (33) | <.001 | 28 (33) | 65 (33) | 1 (20) | .8 |
| n eval = 579 | n eval = 288 | n eval = 198 | ||||||
| Palpable splenomegaly, n (%) | 179 (31) | 33 (11) | 146 (51) | <.001 | 36 (42) | 107 (54) | 3 (60) | .2 |
| n eval = 578 | n eval = 290 | n eval = 288 | n eval = 198 | |||||
| Serum albumin, median (range), g/dL | 3.9 (2-5.1) | 4 (2.9-5.1) | 3.8 (2-4.9) | <.001 | 3.8 (2-4.9) | 3.8 (2-4.8) | 3.85 (3.1-4.4) | .6 |
| n eval = 389 | n eval = 157 | n eval = 232 | n eval = 71 | n eval = 157 | n eval = 4 | |||
| Serum albumin <3.5 g/dL, n (%) | 87 (22) | 18 (11) | 69 (30) | <.0001 | 18 (25) | 50 (32) | 1 (25) | .6 |
| n eval = 389 | n eval = 157 | n eval = 232 | n eval = 71 | n eval = 157 | n eval = 4 | |||
| Serum ALP, median (range), U/L | 124 (19-3680) | 92 (30-1957) | 178.5 (19-3680) | <.001 | 195 (33-2004) | 170 (19-3680) | 240 (139-1423) | .4 |
| n eval = 547 | n eval = 269 | n eval = 278 | n eval = 82 | n eval = 191 | ||||
| Serum ALP > UNL, n (%) | 296 (54) | 101 (38) | 195 (70) | <.001 | 58 (71) | 132 (68) | 5 (100) | .3 |
| n eval = 547 | n eval = 269 | n eval = 278 | n eval = 82 | n eval = 191 | ||||
| KITD816V, n (%) | 279 (78) | 141 (82) | 138 (75) | .09 | 41 (87) | 97 (71) | 0 (0) | .01 |
| n eval = 357 | n eval = 172 | n eval = 185 | n eval = 47 | n eval = 137 | n eval = 1 | |||
| ASXL1 mutated, n (%) | 25 (17) | 0 (0) | 25 (23) | <.001 | 4 (15) | 21 (26) | 0 (0) | .4 |
| n eval = 150 | n eval = 43 | n eval = 107 | n eval = 26 | n eval = 80 | n eval = 1 | |||
| RUNX1 mutated, n (%) | 5 (3) | 0 (0) | 5 (5) | .15 | 0 (0) | 5 (6) | 0 (0) | .4 |
| n eval = 150 | n eval = 43 | n eval = 107 | n eval = 26 | n eval = 80 | n eval = 1 | |||
| NRAS mutated, n (%) | 4 (3) | 0 (0) | 4 (4) | .19 | 0 (0) | 3 (4) | 1 (100) | <.001 |
| n eval = 150 | n eval = 43 | n eval = 107 | n eval = 26 | n eval = 80 | n eval = 1 | |||
| Adverse mutations, n (%) | 31 (21) | 0 (0) | 31 (29) | <.001 | 4 (15) | 26 (33) | 1 (100) | .07 |
| n eval = 150 | n eval = 43 | n eval = 107 | n eval = 26 | n eval = 80 | n eval = 1 | |||
| Abnormal karyotype, n (%) | 53 (15) | 8 (7) | 45 (22) | <.001 | 4 (8) | 40 (26) | 1 (50) | .02 |
| n eval = 348 | n eval = 142 | n eval = 206 | n eval = 2 | |||||
| Median follow-up (range), mo | 34 (0-496) | 51 (0-357) | 23 (0-496) | <.001 | 35 (0-496) | 20 (0-291) | 2 (1-30) | .06 |
| Deaths, n (%) | 239 (41) | 44 (15) | 195 (67) | <.001 | 42 (49) | 150 (75) | 3 (60) | <.001 |
| Leukemic transformations, n (%) | 9 (2) | 0 (0) | 9 (3) | <.001 | 1 (1) | 8 (4) | 0 (0) | .4 |
Bold indicates statistical significance (P < .05).
BM, bone marrow; n eval, number evaluable; UNL, upper normal limit.