Table 1.
Characteristics of 198 melanocytic specimens analyzed for TERT promoter mutations and classified for diagnosis (melanoma, nevus or diagnostically uncertain melanocytic proliferation) after interobserver review
| Characteristic | Primary Melanomas (n=86) | Nevi (n=72) | Uncertain* (n=40) |
|---|---|---|---|
| Number (%) | Number (%) | Number (%) | |
| Laboratory processing of unstained FFPE tissue sections | |||
| University of North Carolina Pathology Laboratories | 81 (94.2) | 66 (91.7) | 40 (100) |
| University of Rochester Pathology Laboratories | 5 (5.8) | 6 (8.3) | – |
| Sex | |||
| Male | 55 (64.0) | 35 (48.6) | 16 (40.0) |
| Female | 31 (36.1) | 37 (51.4) | 24 (60.0) |
| Age at diagnosis of mole or primary melanoma, yrs | |||
| < 65 | 44 (51.2) | 66 (91.7) | 35 (87.5) |
| ≥ 65 | 42 (48.8) | 6 (8.3) | 5 (12.5) |
| Race | |||
| Whites of European origin | 77 (89.5) | 50 (69.4) | 24 (60.0) |
| Other/unknown | 9 (10.5) | 22 (30.6) | 16 (40.0) |
| Histologic subtype of primary melanoma | |||
| Superficial spreading | 43 (50.0) | – | – |
| Nodular | 12 (14.0) | – | – |
| Lentigo maligna | 16 (18.6) | – | – |
| Acral lentiginous | 6 (7.0) | – | – |
| Other/unclassified† | 9 (10.5) | – | – |
| Anatomic site of mole or primary melanoma | |||
| Head/neck | 28 (32.6) | 19 (26.4) | 4 (10.0) |
| Trunk | 27 (31.4) | 37 (51.4) | 23 (57.5) |
| Upper extremities | 16 (18.6) | 8 (11.1) | 2 (5.0) |
| Lower extremities | 15 (17.4) | 8 (11.1) | 11 (27.5) |
| Solar Elastosis adjacent to the melanocytic lesion | |||
| Absent | 21 (24.4) | 43 (59.7) | 34 (85.0) |
| Present | 59 (68.6) | 9 (12.5) | 5 (12.5) |
| Indeterminate | 6 (7.0) | 20 (27.8) | 1 (2.5) |
| Contiguous nevus | |||
| Absent | 75 (87.2) | – | – |
| Present | 11 (12.8) | – | – |
| Melanocytic nevus type | |||
| Intradermal | – | 17 (23.6) | – |
| Common acquired | – | 9 (12.5) | – |
| Congenital pattern | – | 14 (19.4) | – |
| Dysplastic | – | 14 (19.4) | – |
| Spitz | – | 9 (12.5) | – |
| Other‡ | – | 9 (12.5) | – |
| Breslow thickness of primary melanoma, mm | |||
| Median (range) | 1.74 (0.37–17.00) | – | – |
| 0.01 to 2.00 | 45 (52.3) | – | – |
| > 2.00 | 41 (47.7) | – | – |
| Ulceration of primary melanoma | |||
| Absent | 52 (60.5) | – | – |
| Present | 33 (38.4) | – | – |
| Indeterminate | 1 (1.2) | – | – |
| Mitoses of primary melanoma | |||
| Absent | 17 (19.8) | – | – |
| Present | 69 (80.2) | – | – |
| AJCC tumor stage at diagnosis (8th edition) | |||
| 1a/1b/2a | 38 (44.2) | – | – |
| 2b/3a/3b/4a/4b | 48 (55.8) | – | – |
| AJCC overall stage at diagnosis (8th edition) | |||
| IA/IB | 34 (39.5) | – | – |
| IIA/IIB/IIC | 19 (22.1) | – | – |
| IIIA/IIIB/IIIC | 25 (29.1) | – | – |
| IV | 3 (3.5) | – | – |
| Unknown | 5 (5.8) | – | – |
| Tumor infiltrating lymphocyte (TIL) grade | |||
| Absent | 20 (23.3) | – | – |
| Present | 65 (75.6) | – | – |
| Indeterminate | 1 (1.2) | – | – |
| Pigment of the melanocytic lesion | |||
| Absent | 16 (18.6) | 12 (16.7) | 7 (17.5) |
| Present | 70 (81.4) | 60 (83.3) | 33 (82.5) |
| Regression | |||
| Absent | 70 (81.4) | – | – |
| Present | 16 (18.6) | – | – |
Melanocytic proliferations were considered diagnostically uncertain if there was interobserver disagreement between any of 3 dermatopathology readers or the pathology report diagnosis of nevus vs. melanoma or one of the dermatopathogists or pathology report described the specimen as having uncertain diagnosis.
Other types of melanoma include nevoid (n=2), desmoplastic (n=1), spindle cell (n=1), spitzoid (n=1) and unclassified (n=4). All of these were TERT-positive except two of the unclassified melanomas.
Other includes cellular blue nevus (n=2), combined intradermal or sclerotic blue nevus, not cellular (n=1), combined nevus with compound congenital pattern and deep penetrating nevus (n=2), pigmented spindle cell nevus (n=2) and proliferative nodule in congenital pattern nevus (n=2).