10.5826/dpc.1202a94
Introduction: Nevus-associated melanoma (NAM) accounts for almost one third of all cutaneous melanomas; it is often associated with younger age, trunk location and lower Breslow’s thickness compared to de novo melanoma (DNM).
Objectives: To define the prevalence of NAM in a tertiary referral Center in Italy and to analyze its distribution according to demographics, clinical and histopathological variables
Methods: Data were retrospectively retrieved from the archive of the Pathology Unit from June 2011 to August 2020. NAMs were compared with DNMs according to demographic, clinical and histopathological variables.
Results: A total of 2806 consecutive cases of melanoma were excised in 2537 patients. Of these, 431 (15.4%) were NAM. NAM patients were significantly younger than DNM patients (55.1±14.1 vs. 62.0±15.0 years, p&lt;0.001); they were predominantly located on the trunk (64.0% vs. 47.9% of DNMs). Melanoma located on the head and neck, trunk and upper limbs respectively had 2.3 (95%CI:1.2-4.5, p:0.014), 3.2 (95%CI:2.1-5.1, p&lt;0.001) and 3.5 (95%CI:2.0-6.1, p&lt;0.001) more odds to be NAM than those on the lower limbs.
Conclusions: Our results confirm the association of NAM with younger age and trunk location. We also demonstrated that body site differences of NAM distribution are enhanced before the sixth decade of life.
text/xml
2160-9381
2084
en
Riccardo Pampena
https://creativecommons.org/licenses/by-nc/4.0
Dermatology Practical & Conceptual
de novo melanoma
Prevalence and clinical-pathological features of nevus-associated versus de novo melanoma: a retrospective cross-sectional study of 2806 cases
Text.Serial.Journal
https://dpcj.org/index.php/dpc
Original Article
2022-05-02
2021-09-30
2022-05-02
2022-05-24
e2022094
Dermatol Pract Concept
Introduction: Nevus-associated melanoma (NAM) accounts for almost one third of all cutaneous melanomas; it is often associated with younger age, trunk location and lower Breslow’s thickness compared to de novo melanoma (DNM).
Objectives: To define the prevalence of NAM in a tertiary referral Center in Italy and to analyze its distribution according to demographics, clinical and histopathological variables
Methods: Data were retrospectively retrieved from the archive of the Pathology Unit from June 2011 to August 2020. NAMs were compared with DNMs according to demographic, clinical and histopathological variables.
Results: A total of 2806 consecutive cases of melanoma were excised in 2537 patients. Of these, 431 (15.4%) were NAM. NAM patients were significantly younger than DNM patients (55.1±14.1 vs. 62.0±15.0 years, p&lt;0.001); they were predominantly located on the trunk (64.0% vs. 47.9% of DNMs). Melanoma located on the head and neck, trunk and upper limbs respectively had 2.3 (95%CI:1.2-4.5, p:0.014), 3.2 (95%CI:2.1-5.1, p&lt;0.001) and 3.5 (95%CI:2.0-6.1, p&lt;0.001) more odds to be NAM than those on the lower limbs.
Conclusions: Our results confirm the association of NAM with younger age and trunk location. We also demonstrated that body site differences of NAM distribution are enhanced before the sixth decade of life.
Riccardo Pampena
2022/05/02
10.5826/dpc.1202a94
e2022094
Centro Oncologico ad Alta Tecnologia Diagnostica, Azienda Unità Sanitaria Locale - IRCCS di Reggio Emilia, Reggio Emilia, Italy; Department of Dermatology, University of Modena and Reggio Emilia, Modena, Italy
2160-9381
de novo melanoma
en
e2022094
Prevalence and clinical-pathological features of nevus-associated versus de novo melanoma: a retrospective cross-sectional study of 2806 cases
https://dpcj.org/index.php/dpc/article/download/2084/1585
    Prevalence and clinical-pathological features
   of nevus-associated versus de novo melanoma:
 a retrospective cross-sectional study of 2806 cases
               Michela Lai1,2, Simonetta Piana3, Giovanni Pellacani4, Caterina Longo1,2,
                                         Riccardo Pampena1,2


1 Centro Oncologico ad Alta Tecnologia Diagnostica, Azienda Unità Sanitaria Locale - IRCCS di Reggio Emilia, Reggio Emilia, Italy
2 Department of Dermatology, University of Modena and Reggio Emilia, Modena, Italy
3 Pathology Unit, Azienda Unità Sanitaria Locale - IRCCS di Reggio Emilia, Reggio Emilia, Italy
4 Dermatology Clinic, Department of Clinical Internal, Anesthesiological and Cardiovascular Sciences, La Sapienza University of Rome,
  Rome, Italy



Key words: melanoma, nevus-associated melanoma, de novo melanoma
Citation: Lai M, Piana S, Pellacani G, Longo C, Pampena R. Prevalence and clinical-pathological features of nevus-associated versus
de novo melanoma: a retrospective cross-sectional study of 2806 cases. Dermatol Pract Concept. 2022;12(02):e2022094.
DOI: https://doi.org/10.5826/dpc.1202a94
Accepted: October 19, 2021; Published: April 2022
Copyright: ©2022 El-Azhary et al. This is an open-access article distributed under the terms of the Creative Commons
Attribution-NonCommercial License (BY-NC-4.0), https://creativecommons.org/licenses/by-nc/4.0/, which permits unrestricted
noncommercial use, distribution, and reproduction in any medium, provided the original authors and source are credited.
Funding: None.
Competing interests: None.
Authorship: All authors have contributed significantly to this publication.
Corresponding author: Caterina Longo, MD, PhD, Department of Dermatology, University of Modena and Reggio Emilia, Italy, Azienda
Unità Sanitaria Locale – IRCCS di Reggio Emilia, Centro Oncologico ad Alta Tecnologia Diagnostica-Dermatologia, Viale Risorgimento,
80, 42123, Reggio Emilia, Italy. E-mail: longo.caterina@gmail.com




  ABSTRACT             Introduction: Nevus-associated melanoma (NAM) accounts for almost one third of all cutaneous
                       melanomas; it is often associated with younger age, trunk location and lower Breslow’s thickness
                       compared to de novo melanoma (DNM).
                       Objectives: To define the prevalence of NAM in a tertiary referral Center in Italy and to analyze its
                       distribution according to demographics, clinical and histopathological variables
                       Methods: Data were retrospectively retrieved from the archive of the Pathology Unit from June 2011
                       to August 2020. NAMs were compared with DNMs according to demographic, clinical and histo-
                       pathological variables.
                       Results: A total of 2806 consecutive cases of melanoma were excised in 2537 patients. Of these,
                       431 (15.4%) were NAM. NAM patients were significantly younger than DNM patients (55.1±14.1
                       vs. 62.0±15.0 years, p<0.001); they were predominantly located on the trunk (64.0% vs. 47.9%
                       of DNMs). Melanoma located on the head and neck, trunk and upper limbs respectively had 2.3
                       (95%CI:1.2-4.5, p:0.014), 3.2 (95%CI:2.1-5.1, p<0.001) and 3.5 (95%CI:2.0-6.1, p<0.001) more
                       odds to be NAM than those on the lower limbs.




Original Article | Dermatol Pract Concept. 2022;12(02):e2022094                                                                         1
                      Conclusions: Our results confirm the association of NAM with younger age and trunk location.
                      We also demonstrated that body site differences of NAM distribution are enhanced before the sixth
                      ­decade of life.




Introduction
Nevus-associated melanoma (NAM) accounts for almost
one third of all cutaneous melanomas [1]. A growing body
of literature demonstrated that NAM is associated with
younger age, trunk location and lower Breslow’s thickness
compared to de novo melanoma (DNM) [2-9].


Objectives
In this retrospective cross-sectional study, we reviewed our
10-year real-life experience at a tertial referral center for skin
cancers with the aim to analyze the prevalence of NAM and
its distribution according to demographics, clinical and his-
topathological variables.


Methods
From the archive of the Pathology Unit, we retrieved 2806
consecutive cases of skin melanoma excised in 2537 patients
from June 2011 to August 2020: 431 (15.4%) melanomas
were NAM. NAMs were compared with DNMs according
to demographic, clinical and histopathological variables us-
ing the Student’s T and chi square tests; statistical signifi-
cance was set at p<0.05 and age was categorized according
to quartiles. Statistical analysis was performed using the
IBM SPSS 27.0 package (Statistical Package for Social Sci-
ences, IBM SPSS Inc., Chicago, Ill.). The study was approved
by Local Ethical Committee (protocol number: 1249/CE).


Results
    Our study revealed that NAM patients were significantly
younger than DNM patients (55.1 ± 14.1[standard deviation,
SD] versus 62.0 ± 15.0 SD years, P < 0.001), with 67.7%
NAMs having ≤61 years and 52.5% of DNMs being older than
61 years. Moreover, the NAM ratio decreased with increas-
ing age. Interestingly, when considering body site distribution,
a significant higher proportion of NAMs were on the trunk
(64.0% vs. 47.9% of DNMs, NAM ratio: 19.5%) whereas
DNMs were predominantly located on the lower limbs (23.9%
vs. 14.7% of NAM, NAM ratio: 8.1%) (Figure 1).
    No significant differences were found according to sex           Figure 1. Ratio of nevus-associated versus de-novo melanoma ac-
and Breslow’s thickness, while ulceration was significantly          cording to body site and age-groups. DNM = de novo melanoma;
more observed among DNMs (Table 1).                                  NAM = nevus-associated melanoma.



2                                                                       Original Article | Dermatol Pract Concept. 2022;12(02):e2022094
       Table 1. Demographic, clinical and histopathological features of nevus-associated vs. de-novo
                                       melanoma (NAM vs. DNM).
                                                         Nevus-association
                   Variables                           NAM            DNM             NAM ratio             Total          p value
 Age at                ≤50                         176 (40.8%)     576 (24.3%)          23.4%           752 (26.8%)
 excision (y)        51 - 61                       116 (26.9%)     551 (23.2%)          17.4%           667 (23.8%)
                                                                                                                           <0.001
                     62 - 73                        88 (20.4%)     651 (27.4%)          11.9%           739 (26.3%)
                       ≥74                          51 (11.8%)     597 (25.1%)            7.9%          648 (23.1%)
 Sex                    M                          237 (55.0%)    1269 (53.4%)          15.7%          1506 (53.7%)
                                                                                                                            0.551
                         F                         194 (45.0%)    1106 (46.6%)          14.9%          1300 (46.3%)
 Location              HN                           39 (9.0%)      350 (14.7%)          10.0%           389 (13.9%)
                      trunk                        276 (64.0%)    1138 (47.9%)          19.5%          1414 (50.4%)
                                                                                                                           <0.001
                   upper limbs                      66 (15.3%)     320 (13.5%)          17.1%           386 (13.8%)
                   lower limbs                      50 (11.6%)     567 (23.9%)            8.1%          617 (22.0%)
 Stage                in situ                      203 (47.1%)    1183 (49.8%)          14.6%          1386 (49.4%)
                                                                                                                             0.3
                     invasive                      228 (52.9%)    1192 (50.2%)          16.1%          1420 (50.6%)
                  Breslow (mm)          ≤1         181 (79.4%)     881 (73.9%)          17.0%          1062 (74.8%)
                                     >1 & ≤2        27 (11.8%)     134 (11.2%)          16.8%           161 (11.3%)
                                                                                                                            0.107
                                     >2 & ≤4        11 (4.8%)       87 (7.3%)           11.2%            98 (6.9%)
                                         >4          9 (3.9%)       90 (7.6%)             9.1%           99 (7.0%)
                     Ulceration superficial         11 (4.8%)      106 (8.9%)             9.4%           117 (8.2%)         0.041
 Total                                                  431           2375              15.4%               2806

NAM, nevus-associated melanoma; DNM, de-novo melanoma; y, years; M, male; F, female, HN, head and neck; mm, millimeters.


    To identify major independent factors associated with          [1]. We also demonstrated that body site differences of NAM
NAM status we constructed a multivariable logistic regres-         distribution are enhanced before the sixth decade of life.
sion model with backward variables selection including sex,           Together with previous studies, our findings further sup-
location, ulceration, Breslow and age categories. We demon-        port the existence of 2 divergent pathways of melanoma
strated that melanoma located on the head and neck, trunk          ­development [8,10].
and upper limbs, respectively had 2.3 (95% confidence inter-
val [CI]1.2 -4.5, P = 0.014), 3.2 (95% CI 2.1-5.1, P <0.001)
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