Incidence of New and Changed Nevi and Melanomas Detected Using Baseline Images and Dermoscopy in Patients at High Risk for Melanoma

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STUDY Incidence of New and Changed Nevi and Melanomas Detected Using Baseline Images and Dermoscopy in Patients at High Risk for Melanoma

Jeremy P. Banky, MBBS; John W. Kelly, MDBS; Dallas R. English, PhD; Josephine M. Yeatman, MBBS, FACD; John P. Dowling, MBBS, FRCPA

Objective: To determine the incidence of new, changed, Results: The incidence of new, changed, and regressed and regressed nevi and melanomas in a cohort of pa- nevi decreased with increasing age (PϽ.001), whereas tients at high risk for melanoma using baseline total body the incidence of melanomas increased (P=.05). The num- photography and dermatoscopy. ber of dysplastic nevi at baseline was positively associated with the incidence of changed nevi (PϽ.001) and Design: Cohort study of patients at high risk for mela- melanomas (P=.03). The use of baseline photography and noma who underwent baseline cutaneous photography dermatoscopy was associated with low biopsy rates and between January 1, 1992, and December 31, 1997, and early detection of melanomas. The development of mela- had at least 1 follow-up visit by December 31, 1998. noma in association with a preexisting nevus was not di- rectly correlated with a change in a preexisting lesion Setting: Private practice rooms of 1 dermatologist in con- monitored by baseline photography. junction with a public hospital-based, multidisciplinary melanoma clinic in Victoria, Australia. Conclusions: Nevi are dynamic, and only a small per- centage of all new and changed melanocytic lesions are Patients: A total of 309 patients who had at least 1 of the following risk factors for melanoma: personal his- melanomas. Patients younger than 50 years had a lower tory, family history, 100 or more nevi, or 4 or more dys- incidence of melanomas and a higher rate of new, changed, plastic nevi. and regressed nevi when compared with patients older than 50 years. A new or changed pigmented lesion is more Main Outcome Measures: Number of new, changed, likely to be a melanoma in patients older than 50 years. and regressed nevi and melanomas detected and excised during the study interval. Arch Dermatol. 2005;141:998-1006

UTANEOUS SURVEILLANCE Not all of these lesions are suggestive of has been well described as melanoma, and along with dermatos- an effective method for copy, many can be managed with reimag- early detection of mela- ing and further follow-up. This study aims noma.1-5 An important aid to identify the proportion of new and toC this screening process is baseline cutaneous photography. This has been re- For editorial comment ported to be an efficient method of detecting changes that are suggestive of melanoma see page 1032 and as a means to minimize unnecessary changed lesions that are melanomas, as surgery.1,3,5,6 well as the incidence of melanomas and new, changed, and regressed nevi. Author Affiliations: CME course available at Dermatology Unit (Drs Banky, www.archdermatol.com METHODS Kelly, and Yeatman) and Victorian Melanoma Service With photographic cutaneous surveil- (Drs Banky, Kelly, and PATIENTS Dowling), The Alfred, and The lance, a high incidence of melanoma and Cancer Council Victoria early detection of melanoma in high-risk We recruited patients at the private consult- 1,3,5,7 (Dr English), Victoria, patients has been reported. In following rooms of 1 dermatologist (J.W.K.) in con- Australia. ing up such patients, many new and junction with the Victorian Melanoma Ser- Financial Disclosure: None. changed pigmented lesions are detected. vice, a state-based multidisciplinary consultative

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©2005 American Medical Association. All rights reserved. Downloaded From: https://jamanetwork.com/ on 09/27/2021 treatment service for cutaneous melanoma (J.W.K., J.P.B., and Biopsy specimens were not obtained of all changed and new J.P.D.). Between January 1, 1992, and December 31, 1997, pa- pigmented lesions. If melanoma could not be confidently ex- tients 16 years or older who presented to the consulting rooms cluded by clinical examination and dermatoscopy, an exci- for full-body cutaneous examination were assessed for eligi- sional biopsy was performed. All new and changed pigmented bility. Baseline skin surface photography was offered if a pa- lesions not excised were recorded. Pigmented lesions re- tient had at least 1 of the following risk factors for melanoma: moved for cosmetic reasons that were not clinically suggestive 4 or more clinically dysplastic nevi,8,9 100 or more melano- of melanoma were not counted. cytic nevi,8,9 a personal history of melanoma,10,11 or a family his- All melanomas diagnosed on follow-up were recorded as new tory of melanoma.12,13 or changed lesions when compared with baseline photo- All 309 (168 female and 141 male) patients who had base- graphs. All melanomas were examined by a single dermatopa- line photographs and had at least 1 follow-up visit by Decem- thologist (J.P.D.). Tumor type was classified according to ber 31, 1998, were included in the study. Patients were di- McGovern et al16 as superficial spreading melanoma, nodular vided according to their age at the time of photography: younger melanoma, or lentigo maligna melanoma, and the levels of in- than 30 years, 30 to 39 years, 40 to 49 years, and 50 years or vasion were recorded as I through V according to Clark et al.17 older. At entry into the study, patients were advised about their Histologic evidence of an associated nevus and the thickness high risk of melanoma, 3-month self-examination was recom- of the melanomas were also recorded. mended, clinical features of early melanoma were discussed, and appropriate sun protection measures were described. STATISTICAL ANALYSIS

IMAGING AND EQUIPMENT Incidence rates were calculated for melanomas, new nevi, nevi that changed, and regressed nevi. Duration of follow-up was Patients had a set of 14 baseline cutaneous photographs, each calculated from the date of photography to the date of the last view defined by easily located anatomical reference points follow-up visit. All relevant lesions were included in the cal- (Figure 1). The scalp, dorsum of hands, palms, soles, and culations, regardless of how many each patient had during fol- genitalia were not routinely photographed. A 35-mm single- low-up. We calculated overall rates and rates separately by the Ͻ Ն lens reflex camera (Nikon FM2; Nikon Corporation, Tokyo, baseline age ( 30, 30-39, 40-49, and 50 years), sex, num- Ͻ Ն Japan) equipped with a 105-mm macromodel lens capable of ber of dysplastic nevi at baseline ( 4, 4-10, 11-20, and 21), Ͻ Ն focusing at a magnification of 1:2 or greater was used. The and total number of nevi ( 100 and 100). Negative bino- patient was positioned in front of a gray background, and 2 mial regression was used to estimate rate ratios, confidence in- electronic studio flashes (1200 W-seconds), each diffused tervals, and P values for each of these variables. using large soft boxes, were positioned at 45° to the patient. The melanoma rate among patients was compared with the This softened any coarse shadows. Color slides were devel- rate in all residents of Victoria by calculating the standardized oped from Fujichrome 100 film (Fujifilm, Tokyo, Japan) and incidence ratio with adjustment for calendar year, sex, and age projected using a Kodak Ektagraphic Projector (Kodak, Roch- in 5-year groups. All in situ and invasive melanomas in the popu- ester, NY). lation of Victoria from 1992 to 1998 and in the patients were included in this analysis (data provided by the Victorian Can- cer Registry on July 26, 2002).18 A jackknife confidence inter- DATA COLLECTION val was constructed to allow for the multiple melanomas per patient. All analyses were performed with Stata statistical soft- The baseline was the date of the patient’s initial cutaneous pho- ware, version 7 (Stata Corporation, College Station, Tex). tography. At a patient’s first examination, the number of dysplastic nevi was recorded in ranges of 0 to 10, 11 to 20, and 21 or more. In addition, the total number of melanocytic nevi was RESULTS estimated and recorded in ranges of 100 or less and more than 100. PATIENT CHARACTERISTICS A nevus was considered dysplastic if it had both clinical14 and dermatoscopic15 features consistent with the diagnosis. Clini- Table 1 gives the number of patients who met each of cally, a dysplastic nevus had a macular component and showed the eligibility criteria. The median age at baseline was 38 at least 3 of the following 5 clinical features: ill-defined bor- years (age range, 16-74 years). The median number of der, irregularly distributed pigmentation, background ery- follow-up visits following photography was 3 (range, thema, maximum diameter greater than 5 mm, and irregular border.14 1-18). The median length of follow-up was 34 months Follow-up of the patients was scheduled at 3-, 6-, or 12- (range, 2-79 months). month intervals. At each visit, total body cutaneous examination was performed by the study dermatologist (J.W.K.), and CHANGED NEVI all melanocytic nevi were compared with baseline photographs. Using these images, the number of new, changed, and A total of 311 changed nevi were detected. Seventy-one completely regressed nevi was recorded at each visit. No dis- nevi had no data for the type of change detected. Of those tinction was made between common nevi and dysplastic nevi nevi with the change documented, the most frequent and between nevi detected at different anatomical sites when changes were in size (67%), color (15%), and both size recording the incidence of new, changed, and regressed nevi. and color (14%). Changes in shape (2%) and all 3 changes The specific changes were classified according to gross mac- together (2%) were not common. Fifty-three (17%) of the roscopic clinical changes in color, size (diameter), and shape that were evident by comparison with the baseline photo- changed nevi were excised (Table 2). Of these, almost graphs of large body regions (Figure 2). Minor changes of clini- half were dysplastic nevi and 14 (26%) were melanomas. cally insignificant magnitude were not recorded. A new nevus The incidence of changed nevi was 329 per 1000 per- was one that appeared after baseline (Figure 3). A nevus was son-years (Table 3). The rate decreased with increas- recorded as regressed if it had completely disappeared. ing age and was more than 2-fold greater for patients

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C D

E F

Figure 1. Baseline cutaneous photographs used with each view defined by easily located anatomical reference points. A, Head and neck; B, anterolateral thighs; C, anterolateral lower legs; D, lateral torso and upper limb; E, buttocks and posterior thighs; F, posterior lower legs; G, chest; H, abdomen; I, upper back; and J, lower back.

younger than 30 years. The incidence was also higher in NEW NEVI patients with higher numbers of dysplastic nevi at baseline but showed no association with the patient’s sex or Two hundred sixty-two new pigmented lesions were de- the number of common nevi at baseline (Table 3). tected (Table 4). Of these, biopsies were performed on

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Figure 2. Photographs of the posterior part of the legs. A, Baseline photograph of the posterior part of the legs at the initial visit. B, View of a changed pigmented lesion on the left posterior part of the calf compared with the baseline image. Arrows indicate the lesion.

18 (7%), yielding 4 melanomas (Table 2). The inci- mas in changed lesions (Table 6). Only 1 of the 6 in situ dence of new pigmented lesions was 277 per 1000 person- melanomas among the changed lesions had histologic evi- years (Table 4). The rate of appearance of new nevi was dence of an associated nevus (Table 6). highest in patients younger than 30 years at baseline. The Assuming that none of the lesions that did not un- rate was not associated with the patient’s sex or number dergo biopsy was a melanoma, then 1 (0.4%) of 252 new of dysplastic nevi at baseline but was highest, albeit not lesions identified in patients younger than 50 years at pho- significantly, in those with the largest number of com- tography was a melanoma compared with 3 (30%) of 10 mon nevi at baseline. new lesions identified in older patients. Similarly, 9 (3%) of 288 changed lesions in patients younger than 50 years COMPLETELY REGRESSED NEVI were melanomas compared with 5 (22%) of 23 changed lesions in older patients. The overall ratio of benign to Eighty-six nevi regressed completely (Table 5). The in- malignant biopsy results was 2.8. It was 4.5 in patients cidence of disappearing pigmented nevi was 91 per 1000 younger than 50 years and 0.75 in older patients. person-years (Table 5). The rate decreased with increas- Most (77%) of the melanomas detected were Clark level ing age and was higher in men but showed no consis- I or II. For the invasive melanomas, 80% were no more tent relationship with the number of dysplastic nevi at than 0.75 mm thick; the median thickness was 0.39 mm. baseline and no association with the number of com- One melanoma detected was a nodular melanoma, Clark mon nevi at baseline (Table 5). level IV, and 2.45 mm thick, with an associated nevus. This melanoma was detected by the patient as a changing le- MELANOMAS sion on self-examination between visits. On comparison with the photographs, this melanoma had increased in size Eighteen melanomas were detected in 16 patients during the 6 months between follow-up visits. (Table 6). Seventeen melanomas were detected at fol- The overall incidence of melanoma was 19 per 1000 low-up visits; 4 were new lesions and 14 were changed person-years (Table 7), which was 34 (95% confi- lesions. One melanoma was found by the patient be- dence interval, 21-54) times higher than that in the Vic- tween visits (Table 6). Two melanomas were detected torian population of the same age and sex. The rate was within 6 months of the baseline photography as changes highest in patients 50 years or older. Patients with greater in both size and color. Fifteen superficial spreading mela- numbers of dysplastic nevi had a higher melanoma in- nomas, 2 lentigo maligna melanomas, and 1 nodular mela- cidence, but there was no positive association with the noma were diagnosed during the study period. The me- number of common nevi at baseline. dian time to diagnosis of each patient’s melanoma after photography was 26 months (range, 5-72 months). The presence of an associated nevus histopathologi- COMMENT cally showed little relationship with the clinical history of the pigmented lesion. Of the 4 melanomas that pre- Our study confirms that nevi are dynamic lesions.19-23 In sented as new lesions, 2 showed histologic evidence of these high-risk patients, increased rates of melanoma were an associated nevus compared with 8 of the 14 melano- found in all age groups. Patients younger than 50 years,

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Risk Factors No. of Patients No. of nevi at first visit Յ100 54 Ͼ100 255 No. of dysplastic nevi at first visit Յ10 144 11-20 113 Ն21 52 Family history of melanoma No 222 Yes 87 Personal history of melanoma No 219 Yes 90

Table 2. Histopathologic Diagnosis of All Changed and New Pigmented Lesions That Were Considered Suggestive of Melanoma and Excised

Histopathologic No. of Changed No. of New Diagnosis Pigmented Lesions Pigmented Lesions B Melanoma 14 4 Dysplastic nevus 25 5 Spitz nevus 1 2 Common benign nevus 9 2 Pseudomelanoma 1 0 Other 3 5 Total 53 18

creased with increasing age. Histologically, Lund and Stobbe22 demonstrated that with increasing age, nevi become less active and more mature so that fewer changes and less regression occur. In our patients, approximately one third had a chang- Figure 3. Photographs of the abdomen. A, View of the abdomen of the ing nevus each year. This rate of change is far less than patient at the initial visit (baseline photograph). B, Close-up view of a new 20 pigmented lesion (arrow) appearing on the midabdomen. that found by Halpern et al, with 51% of all evaluated nevi in the mean 89-month follow-up showing clinical signs of change. This difference is likely to be explained and especially those younger than 30 years, had more new, by the different thresholds for detecting change in each changed, and regressed nevi and fewer melanomas de- study. We recorded only the gross clinical changes in nevi tected. In contrast, patients older than 50 years had more as determined using baseline photographs of large body melanomas detected and had fewer new nevi appear or regions. Halpern et al,20 on the other hand, examined nevi existing nevi change or regress. Therefore, a new or with macrophotography and recorded minor changes. changed nevus in an older patient is much more likely Many cross-sectional studies21,24-27 have reported that to be a melanoma than in a younger patient. In patients total nevus counts decrease with increasing age. This has younger than 50 years, less than 1% of all new lesions generally been attributed to regression of nevi with age.19-21 were melanomas, whereas in patients older than 50 years, However, in our study the rate at which nevi regressed 30% were melanomas. Similarly, for all changed lesions was less than the rate of appearance of new nevi in all detected in patients younger than 50 years, 3% were mela- age groups, suggesting that declining numbers of nevi nomas, whereas in patients older than 50 years, 22% were with age may be a cohort effect, perhaps reflecting dif- melanomas. ferent sun exposure patterns in childhood years. There Two previous studies support the observation that nevi has been no recent study of nevus numbers by age through become more stable in patients with increasing age. Hal- adult life, and it is possible that current data would not pern et al20 reported that 33% of patients had new dys- show the (cross-sectional) decline with age. It is also pos- plastic nevi appear on their backs during a mean fol- sible that our short study time frame may have been in- low-up of 89 months, with the highest rate occurring in sufficient to demonstrate the expected decline in num- patients younger than 30 years (76%), which then de- bers of nevi with age. Furthermore, the patients in our

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No. of Rate of Changed Lesions Rate Ratio Changed Lesions per 1000 Person-Years Adjusted for Age Variable (n = 311) (n = 329) (95% CI) P Value Age at the time of photography, y Ͻ.001 Ͻ30 126 692 1.0 30-39 102 258 0.4 (0.3-0.7) 40-49 60 223 0.4 (0.2-0.6) Ն50 23 236 0.4 (0.2-0.8) Sex .29 Female 162 314 1.0 Male 149 347 1.2 (0.8-1.8) No. of dysplastic nevi at first visit Ͻ.001 Յ10 93 220 1.0 11-20 115 337 1.4 (0.9-2.2) Ͼ21 103 570 2.9 (1.8-4.7) No. of common nevi at first visit .81 Յ100 57 326 1.0 Ͼ100 254 330 1.1 (0.7-1.7)

Abbreviation: CI, confidence interval.

Table 4. Incidence of New Pigmented Lesions

No. of Rate of New Lesions Rate Ratio New Lesions per 1000 Person-Years Adjusted for Age Variable (n = 262) (n = 277) (95% CI) P Value Age at the time of photography, y Ͻ.001 Ͻ30 155 852 1.0 30-39 59 149 0.1 (0.1-0.2) 40-49 38 141 0.1 (0.1-0.2) Ն50 10 102 0.1 (0.0-0.2) Sex .74 Female 145 281 1.0 Male 117 272 0.9 (0.6-1.5) No. of dysplastic nevi at first visit .12 Յ10 129 306 1.0 11-20 75 220 0.9 (0.5-1.6) Ն21 58 321 1.2 (0.6-2.3) No. of common nevi at first visit .12 Յ100 27 154 1.0 Ͼ100 235 305 1.7 (0.9-3.2)

Abbreviation: CI, confidence interval.

study had large numbers of nevi and dysplastic nevi, and A consensus exists that only new and changed nevi in such patients, the natural history of nevi may be dif- that are clinically suggestive of melanoma require exci- ferent from that in the general population. sion. Using dermatoscopy, Kittler et al29 detected 516 The incidence of melanoma was 34-fold higher than changes in nevi, of which only 75 were removed. Hal- in the general population. Surveillance bias may have con- pern et al20 excised only 48 of 593 changed nevi. Only 17% tributed to this, and similar rates have been demon- of all changed and 7% of all new nevi detected in our pa- strated in other studies of high-risk populations.1,5 tients were removed. Of these biopsy specimens, 26% of The number of dysplastic nevi was positively associ- changed and 22% of new lesions were melanomas. ated with the incidence of melanoma, confirming the In our study, the benign-malignant ratio of lesion widely described1,8,9,28 role of dysplastic nevi as a major biopsy specimens was almost 3:1. This ratio compares risk factor for melanoma and the dose-response relation- with a previous study1 conducted in the same private ship previously observed between numbers of dysplas- practice, in which the benign-malignant ratio was 9:1. tic nevi and melanoma incidence.1 Somewhat surpris- Our lower ratio in this more recent study can be ingly, we found no association between the total numbers explained by the fact that we used dermatoscopy in of common nevi and melanoma rates. However, the broad addition to photography. The combination of photogra- ranges used to record nevus numbers may have masked phy to demonstrate the stability of many nevi that might this expected relationship. otherwise be excised and dermatoscopy to help rule out

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No. of Rate of Regressed Lesions Rate Ratio Regressed Lesions per 1000 Person-Years Adjusted for Age Variable (n = 86) (n = 91) (95% CI) P Value Age at the time of photography, y Ͻ.001 Ͻ30 66 231 1.0 30-39 124 63 0.2 (0.0-0.5) 40-49 84 63 0.1 (0.0-0.5) Ն50 35 20 0.0 (0.0-0.4) Sex .04 Female 32 62 1.0 Male 54 125 2.8 (1.1-7.4) No. of dysplastic nevi at first visit .08 Յ10 144 109 1.0 11-20 113 64 0.7 (0.2-2.5) Ն21 52 100 1.0 (0.2-4.0) No. of common nevi at first visit .89 Յ100 54 74 1.0 Ͼ100 255 95 1.1 (0.3-4.2)

Abbreviation: CI, confidence interval.

Table 6. Melanomas Detected

Clark Thickness, New or Changed Associated Nevus Time to Detection, No. Type Level mm According to Photographs Histologically Detection Method mo 1 NM IV 2.45 Changed Yes Patient 25 2 SSM II 0.8 Changed Yes Photographs 5 3 SSM I . . . New Yes Photographs 46 4 SSM II 0.45 Changed Yes Photographs 24 5 SSM II 0.3 Changed Yes Photographs 37 6 SSM III 0.55 Changed Yes Photographs 21 7 SSM I . . . Changed No Photographs 27 8 LM II 0.35 New Yes Photographs 56 9 SSM III 0.4 New No Photographs 56 10 SSM I . . . New No Photographs 37 11 SSM I . . . Changed No Photographs 46 12 SSM II 0.2 Changed No Photographs 5 13 SSM II 0.35 Changed Yes Photographs 35 14 SSM III 0.37 Changed Yes Photographs 72 15 SSM I . . . Changed No Photographs 22 16 LM I . . . Changed Yes Photographs 53 17 SSM I . . . Changed No Photographs 15 18 SSM I . . . Changed No Photographs 23

Abbreviations: LM, lentigo maligna melanoma; NM, nodular melanoma; SSM, superficial spreading melanoma.

melanoma in many new and changed nevi greatly opsy rates alone from the use of the combination of base- reduced the number of excisions required in our line photography and dermatoscopy. patients. Overall, benign-malignant ratios of 12:1 for In our study, 44% of melanomas were in situ and 80% dermatologists and 30:1 for general physicians have also of the invasive melanomas were less than 0.75 mm thick. been reported.30 Thirty-five percent of melanomas in Victoria for 1995 were When consultations and biopsies are priced at the cur- in situ. The median thickness of invasive melanomas de- rent Australian government’s Medicare schedule rates (No- tected in this study was 0.39 mm, compared with 0.60 vember 2003) and AUD $125 is allowed per set of pho- mm for all invasive melanomas in Victoria diagnosed be- tographs, the cost of diagnosing each melanoma in this tween 1992 and 1998 in persons younger than 72 years. study was AUD $4840. However, if we had a benign- Surveillance played a major role in detection in this study, malignant ratio of 12:1, as has been previously reported with 17 of the 18 melanomas detected by comparison with for dermatologists,30 then the total number of biopsies baseline photographs. would have increased to 234 and the cost of diagnosing The literature disagrees about the proportion of mela- each melanoma would have risen to AUD $6323. Thus, nomas that arise from preexisting benign nevi. At least significant savings are likely to be made in reduced bi- two thirds of patients state that their melanomas arose

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No. of Melanomas Rate of Melanoma per 1000 Rate Ratio Adjusted Variable (n = 18) Person-Years (n = 19) for Age (95% CI) P Value Age at the time of photography, y .05 Ͻ30 3 16 1.0 30-39 6 15 0.9 (0.2-3.7) 40-49 1 4 0.2 (0.0-2.2) Ն50 8 82 4.9 (1.3-19.0) Sex .58 Female 7 14 1.0 Male 11 26 1.3 (0.5-3.6) No. of dysplastic nevi at first visit .03 Յ10 4 9 1.0 11-20 7 20 2.3 (0.6-8.1) Ն21 7 39 4.2 (1.1-15.9) No. of common nevi at first visit .76 Յ100 4 23 1.0 Ͼ100 14 18 0.8 (0.3-2.7)

Abbreviation: CI, confidence interval.

from abnormal growth of an existing mole.31 Friedman baseline total body photography and dermatoscopy to et al32 reported that 70% of patients with histologic evi- monitor pigmented lesions greatly reduces the normally dence of a nevus-associated melanoma had a history of high biopsy rates required to evaluate high-risk patients a preexisting lesion. Early histologic studies reported an and provides large savings in the cost of biopsies and the associated benign nevus in 53% of melanomas,33 whereas morbidity associated with them. In addition, melanomas later studies have shown this association to be lower, on are detected earlier than would otherwise be expected, thus the order of 20% to 30%.32,34-36 In our study, 44% of the reducing the potential for mortality from melanoma. melanomas had no histologic evidence of an associated It is clear that only a small proportion of new and nevus, whereas in our previous study1 this figure was 65%. changed lesions are likely to be melanomas. This is rel- Thus, most melanomas appear to arise de novo accord- evant to physicians in setting their thresholds for per- ing to histologic studies, yet the clinical histories sug- forming biopsies. New and changed lesions are much more gest that melanomas arise from preexisting nevi. likely to be melanoma in patients older than 50 years. In our study, the clinical impression of de novo melanoma vs melanoma that originated from a preexisting nevus based on comparison with baseline photographs was Accepted for Publication: December 7, 2004. not always supported by the histologic findings. We ex- Correspondence: John W. Kelly, MDBS, Victorian Mela- pected that melanomas that presented with change in a noma Service, The Alfred, Commercial Road, Prahran, preexisting pigmented lesion would show histologic evi- Victoria 3181, Australia ([email protected]). dence of an associated nevus, whereas melanomas that Disclaimer: The authors had full access to all the data in appeared as new lesions on normal skin would not. Al- the study and take responsibility for the integrity of the though for invasive melanoma it is possible that evi- data and the accuracy of the data analysis. dence of a preexisting nevus has been destroyed by the Previous Presentations: This study was presented in part melanoma, it is unlikely that a level I melanoma would at the Clinical Oncological Society of Australia 29th An- replace a preexisting nevus. nual Scientific Meeting; November 26, 2002; Sydney, Aus- Five of the 6 in situ melanomas that presented as change tralia; and the British Association of Dermatologists’ 83rd in a preexisting lesion were not associated with a nevus. Annual Meeting; July 3, 2003; Brighton, England. These melanocytic lesions were present at the first con- Additional Information: This study received the Schering- sultation and initially appeared benign on clinical and der- Plough Research Award (Dr Banky) for trainees of the matoscopic examination. During follow-up, these le- Australasian College of Dermatologists. sions underwent suspicious change and excisional biopsies Acknowledgment: We thank Amanda P. Henham, BApp- were performed. It is likely that these pigmented lesions Sci(Photog), for designing the skin surface views and pho- were in situ melanomas from the outset and were clini- tographing all patients in this study. cally stable or slow growing. In addition, 2 of the 4 melanomas that were absent on baseline photographs and REFERENCES evolved as new lesions during follow-up showed histologic evidence of an associated nevus. For these lesions, 1. Kelly JW, Yeatman JM, Regalia C, Mason G, Henham AP. A high incidence of the melanoma and nevus may have evolved simulta- melanoma found in patients with multiple dysplastic naevi by photographic surveillance. Med J Aust. 1997;167:191-194. neously during the interval between follow-up visits. 2. Masri GD, Clark WH Jr, Guerry D IV, Halpern A, Thompson J, Elder DE. Screen- This study shows that nevi continue to change and ap- ing and surveillance of patients at high risk for malignant melanoma result in pear throughout life, at least in high-risk patients. Using detection of earlier disease. J Am Acad Dermatol. 1990;22:1042-1048.

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