Table 2: Summary of tumor characteristics by method of detection.
| Variable | Detection method | p value* | |||
|---|---|---|---|---|---|
| Patient | Non-dermatologist Physician | Dermatologist | All Physicians | ||
| Anatomic site | 0.02 | ||||
| Extremity | 139/231 (60.2%) | 139/231 (60.2%) | 30/231 (13.0%) | 92/231 (29.8%) | |
| Head/Neck | 44/80 (55.0%) | 26/80 (32.5%) | 10/80 (12.5%) | 36/80 (45.0%) | |
| Trunk | 62/172 (36.0%) | 78/172 (45.3%) | 32/172 (18.7%) | 110/172 (74%) | |
| Location | 0.02 | ||||
| Anterior | 102/193 (52.9%) | 58/193 (30%) | 33/193 (17.1%) | 91/193 (47.1%) | |
| Posterior | 68/168 (40.5%) | 71/168 (42.2%) | 29/168 (17.3%) | 100/168 (59.5%) | |
| Lesion diameter, mm, mean (median) | 13.0 ± 10.3 (10) | 12.7 ± 8.5 (10) | 11.9 ± 7.0 (10) | 12.5 ± 8.1 (10) | 0.55 |
| Amelanotic | 22/28 (78.6%) | 3/28 (10.7%) | 3/28 (10.7%) | 6/28 (21.4%) | 0.002 |
| T Stage | < 0.0001 | ||||
| Tis | 52/135 (38.5%) | 47/135 (34.8%) | 36/135 (26.7%) | 83/135 (61.5%) | |
| 1 | 96/201 (47.8%) | 75/201 (37.3%) | 30/201 (14.9%) | 105/201 (52.2%) | |
| 2 | 36/63 (57.2%) | 22/63 (34.9%) | 5/63 (7.9%) | 27/62 (42.8%) | |
| 3 | 32/48 (66.7%) | 15/48 (31.2%) | 1/48 (2.1%) | 16/48 (33.3%) | |
| 4 | 29/34 (85.3%) | 5/34 (14.7%) | 0/34 (0%) | 5/34 (14.7%) | |
| Histologic subtype | 0.03 | ||||
| ALM | 8/12 (66.7%) | 4/12 (33.3%) | 0/12 (0%) | 4/12 (33.3%) | |
| LMM | 42/123 (34.2%) | 48/123 (39%) | 33/123 (26.8%) | 81/123 (75.8%) | |
| Nodular | 40/56 (71.4%) | 15/56 (28.8%) | 1/56 (1.8%) | 16/56 (28.6%) | |
| SSM | 142/274 (51.8%) | 94/274 (34.3%) | 38/274 (13.9%) | 132/274 (48.2%) | |
| Other | 15/21 (71.4%) | 5/21 (23.8%) | 1/21 (4.8%) | 6/21 (38.6%) | |
| Thickness, mm, mean (median, IQR) |
2.11 ± 2.92 (1.07, 0.53-2.40) |
1.26 ± 1.42 (0.76, 0.25-1.51) |
0.60 ± 0.45 (0.50, 0.28-0.80) |
1.11 ± 1.29 (0.61, 0.35-1.25) |
< 0.0001 |
| Mitoses per mm2, mean (median, IQR) |
2.8 ± 0.35 (1, 0-2) |
1.8 ± 0.43 (0, 0-1) |
0.4 ± 0.65 (0, 0-1) |
1.4 ± 0.36 (0, 0-1) |
0.005 |
| Ulceration, present | 40/60 (66.7%) | 20/60 (33.3%) | 0/60 (0%) | 20/60 (33.3%) | 0.009 |
| Node-positive | 21/25 (84.0%) | 3/25 (12.0%) | 1/25 (4.0%) | 4/25 (16.0%) | 0.005 |
*p value based on comparison between patient-detected and all physician-detected melanomas; **Thickness calculated for invasive melanomas only. Abbreviations: ALM: Acral Lentiginous Melanoma; LMM: Lentigo Maligna Melanoma; SSM: Superficial Spreading Melanoma; IQR: Interquartile Range.