Prevalence of subungual melanoma in patients with cutaneous malignant melanoma: A systematic review and meta-analysis

BACKGROUND

Subungual melanoma (SUM) is a rare type of cutaneous malignant melanoma (CMM) associated with poor prognosis, while data regarding its prevalence are scarce.

OBJECTIVES

We sought to provide a comprehensive systematic review and meta-analysis of the prevalence rates of SUM among all types of CMM, considering certain demographic and clinical characteristics.

METHODS

The MEDLINE electronic database was searched systematically to identify eligible studies providing prevalence rate estimates of SUM in patients with CMM. Included studies were further analysed to estimate the relative prevalences of SUM according to study design, study years, geographical region and sex distribution.

RESULTS

Twenty-eight studies met the inclusion criteria. The overall SUM prevalence was 1.9% (95% CI [1.5%-2.3%]). The prevalence of SUM did not differ significantly between population- and hospital-based studies and remained stable over time. However, it was found to be significantly higher in Asians compared to patients of other geographical regions as well as in studies with more men than women compared to those with female preponderance (p < 0.001).

CONCLUSIONS

In all, the overall SUM prevalence among all subtypes of CMM was estimated at 1.9%, without significant changes over time, and was found to exhibit significant variability between subgroups of different geographical regions.

Nail discoloration in pediatric skin of color patients

Nail pigmentation in children can cause significant anxiety in parents and clinicians. Different pigments of the nails, such as yellow, orange, and green, can all occur; however, this paper will focus on the dark pigments: brown, gray, and black pigmentation of the nails. Many causes of dark coloration of the nails exist; almost all causes in pediatric patients are benign and require no treatment. Melanoma is the one diagnosis that physicians do not want to miss. Fortunately, this is extremely rare in children.

Subungual Melanocytic Lesions: Key Clinical and Pathologic Concepts and Biopsy Techniques

Both dermatologists and pathologists sometimes find daunting the evaluation of melanonychia (especially subungual melanocytic lesions) because of the fear of performing nail surgery due to the risk of dystrophy, difficulties processing and interpreting nail biopsy specimens, and a general lack of experience in the field. Nevertheless, mastery of nail biopsy techniques, correct processing and orientation of specimens, and familiarity with the histologic particularities of the nail apparatus can attenuate the undoubted complexity and facilitate the tasks involved. Longitudinal excision is the biopsy technique that ensures the simplest histologic interpretation, and it is associated with a low risk of nail dystrophy when performed correctly. Clinical and epidemiological data are crucial. Subungual melanoma in childhood, for instance, is very rare and even lesions with atypical clinical and/or histologic features are probably benign. The presence of suprabasal melanocytes and other findings that would suggest malignancy at other sites are considered normal in the nail apparatus. Subungual melanoma shows a lentiginous pattern in the early stages of disease, and detection of an inflammatory infiltrate accompanying atypical lentiginous subungual lesions would appear to be one of the first diagnostic findings.

Clinicopathological significance of tumor-infiltrating lymphocytes and programmed death-1 expression in cutaneous melanoma: a comparative study on clinical subtypes

Interactions between immune cells and tumor cells play an important role in tumor progression. We evaluated patterns of tumor-infiltrating lymphocytes (TILs) and programmed death-1 (PD-1) expression in acral and nonacral cutaneous melanoma, and determined their effects on clinicopathological characteristics and biologic responses. We identified 122 cases of cutaneous melanoma, of which 39 were cases of non-nail unit acral melanoma (NNUAM), 35 were cases of nail unit melanoma (NUM), and 48 were cases of nonacral melanoma. Clinicopathological features and survival outcomes were analyzed according to the scores for TILs and PD-1 expression in intratumoral and peritumoral compartments. The effects of the presence of TILs and PD-1 expression on various clinicopathological factors differed according to the clinical subtypes of cutaneous melanoma. The frequency of intratumoral TILs and PD-1 expression were lower in NUM than in the other two subtypes. The density of peritumoral PD-1 was significantly higher in NNUAM. In NUM and nonacral melanoma, a low density of intratumoral TILs and PD-1 was associated with a deeper Breslow thickness and the presence of a vertical growth phase. In NNUAM, a high density of peritumoral TILs and PD-1 was associated with a shallower Breslow thickness and less frequent extracutaneous dissemination. In NNUAM, a high density of peritumoral PD-1 was associated with a better prognosis. This study suggests that the effects of PD-1+ TILs on biological activity differ according to the clinical subtypes of cutaneous melanoma.

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.

Acral lentiginous melanoma: a clinicoprognostic study of 126 cases

BACKGROUND

Although the histopathological subtype of melanoma has not been clearly proven to carry independent prognostic significance, acral lentiginous melanoma (ALM) seems to confer a poorer prognosis mainly because disease is often more advanced at the time of diagnosis.

OBJECTIVES

To investigate the distinctive epidemiological and clinical characteristics of ALM, a peculiar histological entity, and to identify prognostic factors.

METHODS

We performed a register-based review of cases from a single large referral centre, the University Hospital Department of Dermatology, Lyons, France. We reviewed patient demographics, the initial presentation of the lesion, and clinical outcome. ALM-specific and disease-free survival were estimated using the KaplanMeier method and compared using the log-rank test. A Cox model was used to identify prognostic factors.

RESULTS

One hundred and twenty-six patients were identified as having histopathology-proven ALM in our melanoma patient register from 1996 to 2004. There were 46 (37%) subungual ALM and 80 (63%) ALM on soles, palms and nonvolar sites. The mean age at diagnosis was 63 years. There were 44 (35%) men and 82 (65%) women, sex ratio M/F 1 : 1.86. The mean Breslow thickness was 2.51 mm (range: in situ to 20 mm). There was no evidence of overexposure to ultraviolet radiation, nor was there found a predisposing genetic trait. Only 16 (13%) patients recalled a history of trauma. Thirty-four ALM (28%) were unpigmented. The median ALM-specific and disease-free survival were 13.5 and 10.1 years, respectively. The 5-year survival rate was 76%. Multivariate analysis identified tumour thickness, male gender and amelanosis as independent clinical prognostic factors for both ALM-specific and disease-free survival.

CONCLUSIONS

Our study provides specific information on the clinical characteristics and outcome of this uncommon histological subtype of melanoma. However, the pathogenesis remains unknown. Breslow thickness, male gender and amelanosis were significantly associated with a poorer prognosis.

Regressed subungual melanoma simulating cellular blue nevus: managed with sentinel lymph node biopsy

BACKGROUND

Subungual melanoma, a not uncommon presentation of cutaneous melanoma in Asian populations, is easily overlooked as benign and thus is improperly treated.

OBJECTIVE

To present two cases with clinical suspicion of subungual melanoma. Skin biopsies failed to demonstrate the diagnostic features of malignancy.

METHODS

Lymphoscintigraphy and sentinel lymph node (SLN) biopsies were performed to determine regional lymph node status.

RESULTS

Both hematoxylin-eosin and HMB45 staining revealed melanoma cells in the SLN of the patient. The second patient's SLN was negative for malignant cells, but her excised primary lesion showed extensive regressed melanoma.

CONCLUSION

Regression phenomena are not uncommon for subungual melanoma. An extention biopsy techniques are useful for determining nodal basin status in regressed subungual melanoma.

Concomitant traumas influence prognosis in melanomas of the nail apparatus*

BACKGROUND

In nail apparatus melanomas (NAM), the role of standard melanoma prognostic factors is under discussion. The prognostic influence of traumas to the clinically apparent tumour has not been sufficiently examined.

OBJECTIVES

To estimate the influence of traumas against the background of standard prognostic factors on the course of NAM.

METHODS

In 33 patients (20 women, 13 men, median age 65.0 years) with NAM (median tumour thickness 3.5 mm), we retrospectively examined a detailed history of trauma to the affected extremity at first presentation. Histological or other standard prognostic factors and follow-up were studied prospectively using a standardized protocol.

RESULTS

Of 33 patients, 21 had suffered injury to the clinically apparent melanoma primary between 4 and 72 months prior to definitive surgical treatment (diagnostic biopsy up to 3 months ahead of excision of the melanoma was not considered). Eight of these patients had undergone inadequate therapy procedures. In Kaplan-Meier analysis, trauma to the clinically apparent tumour and tumour thickness were found to be significant prognostic factors for recurrence-free survival, and trauma to the clinically apparent tumour, Clark level and tumour thickness were significant prognosis predictors for overall survival. In Cox's proportional hazards model, trauma to the clinically apparent tumour was found to be a significant and independent risk factor with regard to overall survival (hazard ratio 5.39; P = 0.029). An influence of trauma on the primary pathogenesis of NAM could not be confirmed. Only three patients reported trauma prior to the onset of tumour.

CONCLUSIONS

From our data, trauma to the clinically apparent tumour might be a considerable risk factor in NAM. The diagnosis of NAM should be considered in lesions of the nail apparatus and further deterioration of the prognosis due to inadequate therapeutic attempts or injury to the NAM should be avoided.

"Functional" surgery in subungual melanoma

BACKGROUND

Subungual melanomas represent approximately 2% to 3% of cutaneous melanomas in White populations. Complete or partial amputation proximal to the distal interphalangeal joint of the digits has been suggested. Recently, we introduced for acral melanomas, similar to lentigo maligna melanoma, limited excision and complete histology of excisional margins (three-dimensional histology).

OBJECTIVE

To evaluate the prognostic relevance of clinical parameters and different surgical management in patients with subungual melanoma.

STUDY DESIGN

From 1980 to 1999, subungual melanoma was diagnosed in 62 of 3,960 stage I and II melanoma patients (1.6%) of the melanoma registry of the Department of Dermatology (University of Tuebingen). A retrospective comparative analysis of two treatment groups was performed: Thirty-one patients had an amputation in or proximal to the distal interphalangeal joint (median follow-up of 55 months), and 31 patients had "functional" surgery with local excision of the tumor and only partial resection of the distal phalanx (median follow-up of 54 months).

RESULTS

In the univariate analysis, the level of invasion (P=0.0059), ulceration (P=0.0024), and tumor thickness (P=0.0004) were significant prognostic factors for recurrence-free survival but not for survival. In a multivariate analysis, only lower tumor thickness and a reduced level of amputation were independent significant prognostic parameters for recurrence-free survival (P=0.035 and P=0.0069). Patients with an amputation in or proximal to the distal interphalangeal joint did not fare better than patients with less radical "functional" surgery.

CONCLUSION

Limited excision with partial resection of the distal phalanx only and three-dimensional histology to assure tumor-free resection margins give better cosmetic and functional results and do not negatively affect the prognosis of patients with subungual melanoma.

Nail apparatus melanoma

Nail apparatus melanoma is a relatively rare variant of melanoma with a disproportionately high mortality when compared with melanoma elsewhere. The aetiology and natural history remain poorly understood. There is no clear epidemiological association with race, skin type or sun exposure. Universally accepted clinical and histological criteria for the diagnosis of early nail apparatus melanoma have not been defined. The two cardinal clinical signs are melanonychia striata and Hutchinson's sign. These are useful but not pathognomonic of melanoma. Diagnostic delay is frequent and patients commonly have advanced disease at the time of diagnosis. Surgical excision is advocated for treatment of stage I disease; however, the most appropriate re-excision margins, including the level of amputation where required, have not been determined. Early diagnosis and excision of the tumour is the only treatment known to increase survival. Adjuvant systemic chemotherapy, isolated limb perfusion, and routine elective lymph node dissection have been used, but no survival benefit has been demonstrated.

Nail melanoma: a review of the literature with recommendations to improve patient management

In this review, the current state of knowledge concerning nail melanoma is summarized. The pathogenesis, histological findings, clinical presentation, treatment and prognosis of this rare form of cutaneous melanoma are discussed. Important clinical clues to the early diagnosis of nail melanoma are highlighted and recommendations to improve the management of patients are suggested.

The incidence and prognosis of nail apparatus melanoma. A retrospective study of 105 patients in four English regions

Our population-based study establishes epidemiological data on age-specific incidence rates, clinical presentation, Breslow microstaging, treatment and survival of nail apparatus melanoma (NAM) patients in England. Four cancer registries, covering a population of 10.6 million, recorded 105 cases of NAM during the period 1984-93. During the same decade there was a total of 7585 patients with cutaneous melanoma and NAM represents 1.4% of all cutaneous melanoma. The incidence rate of NAM in English patients is 0.1 per 100,000 of the population per annum. Amelanotic melanoma was the clinical presentation in 24 of our NAM cases. The overall prognosis is poor with an observed 5 year survival of only 51%. Patients with NAM less than 2.5 mm Breslow depth have a 5 year survival of 88% and are twice as likely to survive compared with those with tumours greater or equal to 2.5 mm in thickness (P < 0. 05). NAM patients are best managed by a multidisciplinary team approach in a few key skin cancer centres.