Long-term Follow-up of Longitudinal Melanonychia in Children and Adolescents Using an Objective Discrimination Index

Clinical features and natural course of pediatric longitudinal melanonychia: A retrospective cohort study in Korea

BACKGROUND

Large studies on the clinical features and natural course of pediatric longitudinal melanonychia (LM) are lacking.

OBJECTIVE

To investigate the clinical features and natural course of pediatric LM METHODS: Retrospective cohort analysis of pediatric patients (age ≤18 years) with LM RESULTS: We examined 703 LM lesions in 381 children. Single, narrow, and homogeneously pigmented fingernail lesions were most frequently seen. Our results suggested that within 3, 4.5, and 9.5 years after onset, approximately 3%, 5%, and 10% of LM lesions, respectively, will completely regress and that single, left-sided, and homogeneously pigmented lesions are more likely to completely disappear. Age of onset, sex, finger/toe position, Hutchinson's sign, and nail dystrophy were not associated with complete regression. During follow up, most cases showed no change in color or width between the first and last visit, and early darkening/wider before stabilization or lightening/narrowing was common. Pigmentation becoming lighter was associated with complete regression; change in width was not.

LIMITATIONS

Retrospective study at a tertiary center CONCLUSION: Our results suggest that clinicians ought to follow up pediatric LM without intervention for several years, even if lesions grow darker or wider. Single, left-sided, and homogeneously colored lesions are more likely to regress.

Should we biopsy melanonychia striata in Asian children? A retrospective observational study

BACKGROUND AND OBJECTIVES

Melanonychia striata is common in children of darker-skinned Asian races, while subungual melanoma is extremely rare and it is difficult to make a diagnosis clinically. However, performing nail unit biopsies in children is particularly challenging and can result in permanent nail dystrophy. The aim of this study was to review the clinical and histologic characteristics of melanonychia striata in pediatric patients of Asian descent to aid in the clinical decision regarding nail biopsy.

METHODS

Sixty-two pediatric patients presenting with melanonychia striata involving single or multiple nails at two tertiary pediatric dermatology clinics in Singapore between 2005 and 2015 were reviewed. Clinical and histopathological data were analyzed, including age at onset, age at presentation, location, color, width, presence of Hutchinson's sign, pseudo-Hutchinson's sign, nail dystrophy, length of follow-up, and clinical evolution. Histopathological assessment was performed by three senior dermatopathologists independently for cases that underwent a nail biopsy.

RESULTS

No cases of subungual melanoma were detected in our series. Solitary melanonychia of the thumbnail with a single uniform color was the most common presentation. Pseudo-Hutchinson's sign was commonly observed. Consensus in histological diagnosis emerged amongst all three dermatopathologists in only half of the cases biopsied.

CONCLUSION

The occurrence of melanoma in Asian children presenting with melanonychia is extremely rare. We recommend clinical follow-up and anticipatory guidance for these patients and nail unit biopsy only in the presence of high-risk clinical features.

The Importance of Dermatoscopy for the Diagnosis of Melanonychia

Melanonychia is the brown or black color of the finger or toe nail due to melanin deposition or melanocytes in the nail plate. The evidence of melanocytic disease is made by the dermatoscope, which allows to highlight the anomalies of the plate. The purpose of our study was to evaluate dermatoscopically the melanonychia, both in the form of stain and longitudinal on finger and/or toe nails in order to establish the type of nail hyperpigmentation.

MATERIALS AND METHOD

33 patients with longitudinal and stain melanonychia were examined with 30x Molemax HD computerized dermatoscope between May 2017-septembre 2018 in this prospective study conducted in the Department of Dermatology of Medical Center Dr. Ianosi (Craiova, Romania). Clinical data included: type of melanonychia, number and name of involved fingers, the presence or absence of fungal infections, nail apparatus tumors or hemorrhage.

RESULTS

The most frequent nail diagnosis was fungal infection (onychomycosis) observed in 18 patients (54.54%), malignant melanoma was diagnosed in 1 patient (3.03%) and the junctional nevus in 4 patients (12.12%). In 18 patients which has longitudinal melanonychia, the most frequent involved finger was the big toe, and in 15 patients which has stain melanonychia, all of them (100%) had affected the big toe, 7 (46.66%) patients had affected the thumb and the same percent the forth finger.

CONCLUSION

Nail dermatoscopy is an important method in establishing the diagnosis of melanonychia and allowed to avoid unnecessary biopsy for melanonychia.

Spontaneous Regression of a Nail Matrix Melanocytic Nevus in a Child

A 14-year-old Hispanic boy presented with a 0.25-mm wide, sharply demarcated, dark brown band of longitudinal melanonychia of the left thumbnail. A clinical diagnosis of nail matrix nevus was made and the boy was scheduled for follow-up. The band showed proximal fading after 6 months and had completely faded after 11 months, with the proximal nail fold showing small dark brown dots on dermoscopy. We documented the spontaneous regression of melanonychia over 11 months.

Assessment of Patient Knowledge of Longitudinal Melanonychia: A Survey Study of Patients in Outpatient Clinics

IMPORTANCE

Subungual melanoma (SM) is a rare subtype of cutaneous melanoma but carries a worse prognosis than similarly staged cutaneous melanomas. Assessing patient knowledge of melanonychia is integral to early diagnosis of SM.

OBJECTIVES

The aim of this paper is to determine patient knowledge of longitudinal melanonychia (LM) and warning signs for SM, frequency of nail self-examinations, and satisfaction of patients with their physician's nail examinations.

DESIGN SETTING AND PARTICIPANTS

We conducted a survey-based study of 363 random patients at Weill Cornell Medicine in New York, USA, performed at 3 different clinics: a general dermatology clinic (n = 167), a nail specialty clinic (n = 44), and a primary care clinic (n = 152).

MAIN OUTCOMES AND MEASURES

Knowledge of the ABCDEF mnemonic for SM was compared to the ABCD mnemonic for cutaneous melanoma. Analyses were performed for patient behavior regarding suspicious nail changes as well as satisfaction with nail counseling and examination.

RESULTS

Only 5% (18/363) of the patients in our study had heard of the ABCDEF mnemonic. In contrast, 9.9% (36/363) of the patients had heard of the ABCD mnemonic for cutaneous melanoma. In total, 37/363 (10.2%) patients reported having LM, 32.4% (12/37) of the patients noted changes in color or width of the band, and 10.8% (4/37) presented with pain or bleeding of the nail, with only 45.9% (17/37) seeking medical attention. Only 11.8% (43/363) of the patients stated that their physician asked them about nail changes, and 1.4% (5/363) of the patients stated that they were counseled about the ABCDEF mnemonic. In comparison, 13.8% (50/363) of the patients were advised on the ABCD mnemonic for the cutaneous melanoma mnemonic. While 70.2% (255/363) of the patients stated that they used sunscreen or wore sun-protective clothing, only 31.4% (114/363) assessed their nails for color changes, with 54.9% (128/233) of the patients categorizing themselves as "very unsatisfied" with the evaluation of their nails by their dermatologist.

CONCLUSIONS AND RELEVANCE

Our data shows that there is a lack of patient knowledge of LM and warning signs for SM. Further testing is needed to determine whether educating patients about LM, warning signs for SM, and nail self-examinations would improve patient outcomes.

Longitudinal melanonychia in an Iranian population: a study of 96 patients

Background

Longitudinal melanonychia (LM) can be a challenging sign since it may be caused by a wide variety of benign and malignant conditions. Cutaneous melanoma is the most important cause of LM. Objective: We performed this study to examine different aspects of LM in Iran, where cutaneous melanoma is rare.

Methods

In this cross-sectional study, we reviewed medical records and pathology reports of a total of 96 patients presenting with LM. These patients had been visited and undergone nail biopsy in Razi Hospital, Tehran University of Medical Sciences, Tehran, Iran. Demographic, clinical, and pathological data were recorded.

Results

The most common diagnosis was junctional nevi in 28 patients (29.2%) followed by melanoma in 19 patients (19.8%). Patients had a mean age of 42.4 years (± 19.4). The mean ages in the groups with junctional nevi and melanoma were 33.3 (± 19.5) and 51.9 (± 17.8), respectively; their difference was statistically significant (P value = 0.001). Hutchinson’s sign was present in 10 patients, 9 of which had melanoma. Also, melanoma was only observed in patients presenting with a solitary nail lesion. Nails mostly affected by melanoma were middle fingers of the hands (7 patients) and thumbs (6 patients). Out of 18 patients with nail dystrophy, 13 (72.2%) were diagnosed with melanoma.

Limitations

Only patients who have undergone biopsy were studied.

Conclusion

Melanoma is an important cause of LM in Iranian patients and should especially be suspected in older patients who present with a solitary nail lesion on their middle finger or thumb. Other findings that direct us toward melanoma are presence of Hutchinson’s sign and nail dystrophy.