Surgical Management of Subungual Melanoma: Mayo Clinic Experience of 124 Cases

Evaluation and diagnosis of longitudinal melanonychia: A clinical review by a nail expert group

Longitudinal melanonychia (LM), a brown-black band on 1 or multiple nails, is commonly encountered in clinical practice. Benign LM may be due to exogenous (external, blood, bacterial, mycotic) or endogenous (melanin) pigment. Histopathologically, melanin-derived LM may result from overproduction of melanin by a normal number of melanocytes (melanocytic activation) due to physiologic, local, systemic, iatrogenic, syndromic, and drug-induced causes, or from benign (nail matrix nevus and lentigo) or malignant (nail unit melanoma [NUM]) melanocyte hyperplasia. A high index of suspicion is necessary to differentiate benign LM and NUM secondary to similarities in clinical presentation, especially in pediatric patients. Benign pediatric LM may exhibit clinical and onychoscopic features resembling adult NUM; thus, a conservative approach with close follow-up is recommended. Onychoscopy and histopathologic examination of nail clippings are useful initial diagnostic tools for LM, avoiding a biopsy or aiding in biopsy planning and patient triage. Nail matrix excisional biopsy is the gold standard for diagnosing/ruling out NUM. For suspicious LM, a nail matrix tangential excisional biopsy is recommended. A longitudinal excision is recommended for cases with a high-likelihood of invasive NUM, which provides information on tumor extension. Herein, we review the current literature to describe the evaluation and diagnosis of LM.

A Review of the Histopathology of Nail Unit Tumors Including Selection of the Optimal Surgical Sampling

Background

A wide variety of tumors can affect the nail unit, with some commonly mistaken as inflammatory or infectious diseases. Obtaining an optimal sample for histopathologic evaluation requires understanding of nail unit anatomy as well as the histopathology of the suspected nail tumor.

Summary

This review discusses clinical and histopathologic features of a subset of benign and malignant nail tumors, including subungual melanoma, nail unit squamous cell carcinoma in situ, nail unit squamous cell carcinoma, onychomatricoma, onychopapilloma, onychocytic matricoma, and onychocytic carcinoma. Optimal surgical sampling techniques for each lesion are presented.

Key Messages

In summary, the clinical and histopathologic features of several common and rare nail unit tumors and the optimal sampling techniques for each lesion are presented in this manuscript. Knowledge of the clinical and histopathologic features of these tumors informs the surgical approach to them and will produce the best patient outcomes.

Ultrasonographic evaluation of nail matrix topography for preservative nail surgery of nail unit melanoma

Recently, functional or preservative surgery has been preferred for nail unit melanoma; however, complete resection of the nail unit, particularly the matrix, is challenging because of its complex structure. This study aims to measure the distance of important nail structures through ultrasonography. Herein, 14 patients without nail deformity were included. The length from the nail cuticle to the distal interphalangeal joint (distance X), to the attachment part of the extensor muscle (distance A), to the median proximal end of the nail matrix (distance B), and to the lateral proximal end of the nail matrix (distance C) were measured. In the axial plane, the length from the highest point of the nail plate to the bottom of the distal phalanx (distance Y) and to the lateral tip of the nail plate (distance D) were measured. On the first fingernail, third fingernail, first toenail, and third toenail, the mean ratio A:X, ratio B:X, ratio C:X, and ratio D:Y were 78.6%, 44.3%, 57.2%, 40.1%, and 84.6%; 55.9%, 64.9%, 40.2%, and 66.4%; 35.6%, 50.8%, 34.3%, and 81.9%; and 57.2%, 59.6%, and 31.7%, respectively. Nail units are often invisible to the naked eye; thus, this study will help identify the approximate scope of excision.

Long-term outcomes after amputation and sentinel node biopsy for subungual melanoma: A single-institution series

BACKGROUND

Subungual melanoma (SUM) is a rare tumor with historically poor outcomes. Thus, the benefit of proximal versus distal amputation in SUM remains unclear.

METHODS

We performed a retrospective review of our prospectively-maintained institutional melanoma database, including SUM and non-subungual acral melanoma (AM) patients who underwent sentinel lymph node biopsy (SLNB) between 1999 and 2022. All SUMs had distal joint or proximal amputations. Primary endpoints were overall survival (OS) and recurrence free survival (RFS). Kaplan-Meier estimates, and Cox univariate and multivariate analyses were performed. Tests were repeated on propensity score matched (PSM) populations in a 2:1 ratio.

RESULTS

123 patients underwent resection with SLNB for SUM (n ​= ​27) and AM (n ​= ​96). Median follow-up was 9.2 years. Unadjusted median OS was 149.1 months for AM and 198.1 months for SUM. In the PSM comparison, median OS and RFS remained comparable between SUM and AM (149.5 months versus 198.1 months; p ​= ​0.612). Sentinel node positivity was associated with significantly worse overall survival outcome (Hazard Ratio 5.49; CI (1.59-18.97), p ​= ​0.007). In the PSM population, male sex was also associated with a significant hazard of death (HR 3.00, CI (1.03-8.71), p ​= ​0.043). Proximal amputations were associated with significantly worse OS (p ​< ​0.002) and RFS (p ​< ​0.01) compared to distal amputations in SUM.

CONCLUSION

SUM was well-treated with distal amputations, and had better OS and RFS compared to SUM treated with proximal amputations. Sentinel lymph node status is an important prognostic factor for SUMs and AMs. SUMs can be treated similarly to AMs with comparably good long-term outcomes.

Esculetin unveiled: Decoding its anti-tumor potential through molecular mechanisms-A comprehensive review

BACKGROUND

The growing complexity of cancer has made it a significant concern in the medical community. Although cancer research has advanced, it is still challenging to create new effective medications due to the limitations and side effects of existing treatment strategies. These are enforcing the development of some alternative drugs from natural compounds with fewer drawbacks and side effects.

AIM

Therefore, this review aims to provide up-to-date, crucial, and all-encompassing data on esculetin's anticancer activity, including all relevant molecular and cellular processes based on in vivo and in vitro investigations.

RESULTS

According to the literature review, esculetin is available in nature and is effective against 16 different types of cancer. The general mechanism shown by esculetin is modulating signaling cascades and its related pathways, like cell proliferation, cell growth, autophagy, apoptosis, necrosis, inflammation, angiogenesis, metastasis, invasion, and DNA damage. Nanoformulation of esculetin improves this natural product's efficacy by improving water solubility. Esculetin's synergistic effects with both natural substances and conventional treatments have been shown, and this method aids in reversing resistance mechanisms by modulating resistance-related proteins. In addition, it has fewer side effects on humans than other phytochemicals and standard drugs with some good pharmacokinetic features.

CONCLUSION

Therefore, until standard chemotherapeutics are available in pharmaceutical markets, esculetin should be used as a therapeutic drug against various cancer types.

Differences in the Clinical and Molecular Profiles of Subungual Melanoma and Acral Melanoma in Asian Patients

Subungual melanoma (SUM) is a rare type of malignant melanoma that arises beneath the nails. SUM is categorized as a type of acral melanoma (AM), which occurs on the hands and feet. SUM is an aggressive type of cutaneous melanoma that is most common among Asian patients. Recent studies reveal that SUM and AM might have different molecular characteristics. Treatment of melanoma relies on analysis of both clinical and molecular data. Therefore, the clinical and molecular characteristics of SUM need to be established, especially during metastasis. To define the mutation profiles of SUM and compare them with those of AM, we performed next-generation sequencing of primary and metastatic tumors of SUM and AM patients. Subungual location was a better independent prognostic factor than acral location for better overall survival (p = 0.001). Patients with SUM most commonly had the triple wild-type (75%) driven by GNAQ (58%) and KIT (25%) mutations, whereas patients with AM had BRAF (28.6%) and RAF (14.3%) molecular types of mutations. Single-nucleotide variations (SNVs) were more common in SUM than in AM, whereas copy number alterations (CNAs) were more common metastatic lesions of AM. Metastatic tumors in patients with SUM and AM showed increases in CNAs (43% and 80%, respectively), but not in SNVs. The number of CNAs increased during metastasis. When compared with AM, SUM has distinct clinical and molecular characteristics.

Evaluation of the Knowledge of Primary Care Physicians About Important Nail Diseases Before and After a Short Online Training

INTRODUCTION

Nail diseases are often diagnosed late with a potential prognostic and functional impact. This could be partly due to knowledge gaps among primary care physicians (PCPs).

OBJECTIVES

To evaluate the knowledge about diagnosis and management of ten common/important nail conditions in a population of French PCPs and its improvement after a 31-minute online training session.

METHODS

We submitted 10 pre-test and post-test clinical cases and an educative online course on the diagnosis and the management of nail diseases to 138 volunteer PCPs; 73 completed the whole training path.

RESULTS

Compared to pre-test, more PCPs in the post-test required an urgent second opinion to dermatologist for pigmented melanoma (100% versus 80.3%; P <0.05) and use of inappropriate/dangerous systemic treatment for trauma-induced nail changes was reduced after the training program (0% versus 6.8%; P <0.05). A lack of knowledge remained after training for amelanotic melanoma with an increase of mycological/bacteriological tests (9.6% versus 0%; P <0.05).

CONCLUSIONS

Management of nail diseases by our panel of PCPs was suboptimal and was improved after a short online training.

Adult and Pediatric Nail Unit Melanoma: Epidemiology, Diagnosis, and Treatment

Nail unit melanoma (NUM) is an uncommon form of melanoma and is often diagnosed at later stages. Approximately two-thirds of NUMs are present clinically as longitudinal melanonychia, but longitudinal melanonychia has a broad differential diagnosis. Clinical examination and dermoscopy are valuable for identifying nail findings concerning malignancy, but a biopsy with histopathology is necessary to confirm a diagnosis of NUM. Surgical treatment options for NUM include en bloc excision, digit amputation, and Mohs micrographic surgery. Newer treatments for advanced NUM include targeted and immune systemic therapies. NUM in pediatric patients is extremely rare and diagnosis is challenging since both qualitative and quantitative parameters have only been studied in adults. There is currently no consensus on management in children; for less concerning melanonychia, some physicians recommend close follow-up. However, some dermatologists argue that the "wait and see" approach can cause delayed diagnosis. This article serves to enhance the familiarity of NUM by highlighting its etiology, clinical presentations, diagnosis, and treatment options in both adults and children.

Risk of recurrence of nail unit melanoma after functional surgery versus amputation

BACKGROUND

Minimally invasive nail unit melanoma (NUM) can be treated with functional surgery (FS) instead of amputation.

OBJECTIVE

To determine risk factors associated with recurrence in NUM.

METHODS

We retrospectively reviewed patients with NUM between 2008 and 2022 at a tertiary referral center. Multivariable Cox regression models adjusted for male sex and Breslow thickness (BT) were generated. Receiver operating characteristic analysis was performed to determine optimal cut-off points of the BT for stratifying recurrence risk.

RESULTS

We evaluated 140 NUM cases (33 amputation and 107 FS). The mean BT values were 3.14 ± 2.62 mm (amputation) and 0.70 ± 1.36 mm (FS). Recurrence occurred in 10 (30.30%) patients with amputation and 23 (21.5%) with FS. Distant disease occurred in 10 (30.30%) patients with amputation and 8 (7.48%) with FS. Male sex, greater BT, amelanotic color, ulcers, and nodules were associated with greater risk for recurrence or distant disease. A BT of 0.8 mm was deemed the optimal cut-off for stratifying recurrence risk after surgery (odds ratio, 5.32; 95% CI, 2.04-13.85).

LIMITATIONS

Small sample.

CONCLUSION

FS can be considered for NUM with a BT < 0.8 mm, providing an amputation-sparing benefit. However, NUM with risk factors for recurrence requires patient counselling and close follow-ups.

A Call for Evidence-Based Conservative Management of Nail Unit Malignancies

SUMMARY

Nail unit squamous cell carcinoma and melanoma are the most common malignancies of the nail apparatus. Compared to their cutaneous counterparts, they are diagnosed later and perceived as more aggressive. This may result in overzealous management, including radiographic imaging with poor sensitivity and specificity, interventional nodal staging by sentinel lymph node biopsy, amputation over digit-sparing tumor resections, and elaborate reconstructions after tumor extirpation. In this review article, the authors evaluate the evidence behind several misconceptions in nail malignancy management and provide evidence-based guidance for more conservative care.

Functional Surgery for Subungual Melanoma: Surgical Tips Based on Histological Analysis of 21 Cadavers

BACKGROUND

Amputation has been the standard treatment for subungual melanoma. Although there is growing attention toward a more conservative functional surgery, specific operative techniques are not yet available.

OBJECTIVE

We aimed to provide objective measurements for use in functional surgery by analyzing the anatomy of the nail apparatus obtained from 21 cadavers.

MATERIALS AND METHODS

Nailbed thickness was histologically measured in each subunit, and skin surface anatomy was evaluated to determine the proximal resection margin. Immunohistochemical staining was performed to analyze microvessel distribution according to the nail subunit.

RESULTS

The nailbed thickness was the thinnest at the most proximal point of the nail matrix (thumbs, 1.10 ± 0.42 mm; big toes, 1.15 ± 0.37 mm) and the thickest at the hyponychium (thumbs, 2.86 ± 0.82 mm; big toes, 2.72 ± 0.84 mm). The distance from the eponychium to the skin surface closest to the bony cortex of extensor tendon insertion was 6.92 ± 5.13 mm in thumbs and 5.14 ± 1.59 mm in big toes. The median microvessel density was the highest at the hyponychium (25.74 vessels/mm2) and lowest at the germinal matrix (16.26 vessels/mm2) (p < .05).

CONCLUSION

This histological study offers practical tips, including those to help decide the proximal and deep resection margins, in functional surgery.

Subungual Melanoma: A Single Institution Experience

Despite the changing paradigms of melanoma treatment in recent years, there remains a relative paucity of data regarding subungual melanoma in the literature. From 2002–2018, 25 patients with subungual melanoma were surgically treated at our facility. A retrospective chart review was conducted to collect relevant demographic, clinical, pathologic, and outcomes data. The median age at diagnosis was 69 years. Most patients (60%) were male, and the melanoma lesion was most often located on the foot (68%). Acral-lentiginous was the most common histologic subtype (59%), and the median Breslow thickness was 3.4 mm. Fifteen patients (63%) underwent a sentinel lymph node biopsy as part of their surgical resection, and four of these patients (27%) had metastatic disease in the lymph nodes. In total, 10 patients underwent lymph node dissection of the involved basin. The median follow up was 21 months in this patient population. Age, gender, tumor location, ulceration, and lesion histology were not significantly associated with recurrence free survival (RFS). Increasing Breslow thickness was found to be significantly associated with shorter RFS (HR: 1.07, CI: 1.03–1.55). In total, 13 patients developed a disease recurrence, and RFS rates were 66% at 1 year and 40% at 3 years. Additionally, 91 and 37% of patients were alive at one year and three years, respectively. Subungual melanomas are rare lesions that often have a more advanced stage at diagnosis, which contributes to the poor prognosis of these cutaneous malignancies.

Melanoma of the Hands and Feet (With Reconstruction)

Melanomas only account for 4% of all dermatologic cancers yet are responsible for 80% of deaths. Notably, melanomas of the hand and foot have a worse prognosis when compared with melanomas of other anatomic regions. Likely this is due to intrinsic biologic characteristics, delayed diagnosis, difficult surgical excision due to delicate anatomy, and lack of definitive diagnostic and therapeutic guidelines. The most common locations of melanoma of the hand, in order of decreasing frequency, are subungual area, dorsal surface, and palmar surface. The most common locations of melanoma of the foot are the plantar surface, dorsal surface, and subungual area, in decreasing frequency. Diagnosis of melanoma of the hand and foot can be difficult because the traditional "ABCDE" (asymmetric shape, border, color, diameter, evolution) rules do not apply. Newer acronyms have been proposed in literature including "CUBED" (colored, uncertain, bleeding, enlarged, delayed) and "ABC rule for Subungual Melanoma." Once diagnosed, treatment is primarily surgical excision and reconstruction. The goal for the surgeon is to maintain the function and anatomy of the hand or foot.

Tumor invasion in the hyponychium is associated with distant metastasis and poor prognosis in subungual melanoma: A histologic landscape of 44 cases

BACKGROUND

Subungual melanoma (SUM) has a poor prognosis because of delayed diagnosis. Its progression, consensus on surgical treatment, and correlation with clinical outcomes remain unclear.

OBJECTIVE

We aimed to identify the pattern of dermal invasion in different locations of the nail apparatus and its relationship with prognosis.

METHODS

In this retrospective review of surgically treated SUM patients between January 2011 and April 2019, the nail apparatus was divided into 5 anatomic subunits: the dorsal roof of proximal nail fold, ventral floor of proximal nail fold, germinal matrix, nail bed, and hyponychium. Invasions in the subunits were categorized using 3 criteria: no tumor, in situ tumor, or invasion.

RESULTS

Among 44 cases of SUM, dermal invasion occurred mostly in the distal areas, with 11, 30, 18, 7, and 4 in the hyponychium, nail bed, germinal matrix, ventral floor of proximal nail fold, and dorsal roof of proximal nail fold, respectively. The patients with hyponychial invasion showed a significantly greater Breslow depth (P = .009), a higher rate of lymph node metastasis (P = .019), distant metastasis (P = .036), and shorter disease-free survival (P = .001).

CONCLUSION

Hyponychial invasion is an important prognostic predictor of SUM, given its strong association with invasion depth, metastatic progression, and disease-free survival. Patients with invasion in the hyponychium should undergo more strict workup, treatment, and surveillance.

Melanoma of the Nail Apparatus: An Analysis of Patients' Survival and Associated Factors

BACKGROUND

There are no proper management guidelines for nail apparatus melanoma (NAM).

OBJECTIVE

This study aimed to describe the clinical features, the presence of locoregional and distant metastases and disease-free and overall survival of NAM treated at our institution.

METHODS

A retrospective cohort review of patients with single, primary localized histopathologically confirmed NAM was performed. Collected data consisted of patients' characteristics and tumor features. In addition, local recurrence, locoregional metastases, distant metastases, disease-free survival (DFS) and overall survival (OS) were used as the main outcomes in our analysis.

RESULTS

Thirty patients with NAM were included. The overall survival (OS) in our patients at 5 and 10 years was 85.6 and 73.4%, respectively. DFS was significantly higher in patients with primary tumor location in the hand and without tumor-infiltrating lymphocytes (p value = 0.01 and 0.04, respectively). The patients with in situ melanoma or Breslow thickness <1 mm had a significantly higher chance of DFS and OS (90.0 and 94.1% at 5 years, respectively) than those with thicker NAM (58.3 and 55.6% at 5 years, respectively). A total of 53.3% of 30 patients underwent primary excision and covering with a full-thickness skin graft, while 13.3% of our 30 patients underwent digit amputation. The patients who underwent excision and covering with a full-thickness skin graft showed a complete overall survival (100% at 5 years).

CONCLUSION

Primary tumor location in the hand and lower tumor thickness might be correlated with better patients' survival. The study results suggest that total amputation might not be necessary in all NAM cases.

Management of Nail Unit Melanoma

Nail unit melanoma is an uncommon form of melanoma with worse prognosis compared with nonacral cutaneous melanoma. Nail unit melanoma is often diagnosed at a late stage. Clinical and dermoscopic features may suggest a diagnosis of nail unit melanoma, but confirmation requires histologic analysis. Like the clinical diagnosis, histopathologic diagnosis of nail unit melanoma is also difficult. The surgical management of nail unit melanoma has evolved from aggressive amputations to digit-sparing approaches. This article reviews the clinical presentation, diagnosis, and surgical treatment of nail unit melanoma to promote early diagnosis and rational surgery.

Developing a predictive model for distinguishing invasive nail unit melanoma from nail unit melanoma in situ

BACKGROUND

Clinical information that distinguishes invasive nail unit melanoma from nail unit melanoma in situ before surgery would aid physicians in the decision-making process and estimating prognosis. However, limited information is available on the detailed demographic and dermoscopic features of invasive nail unit melanoma and nail unit melanoma in situ for differential diagnosis.

OBJECTIVE

This study aimed to investigate the demographic data and dermoscopic features of invasive nail unit melanoma and nail unit melanoma in situ and establish a predictive model for differentiating these two forms of nail unit melanoma.

METHODS

A retrospective observational study of ninety-seven patients diagnosed with nail unit melanoma (59 in situ and 38 invasive cases) in four healthcare centres in South Korea (three tertiary referral hospitals and one second referral hospital) from March 2014 to December 2019.

RESULTS

A multivariable analysis revealed that ulcer (odds ratio = 21.6, confidence interval = 2.1-219.8, P = 0.009), total melanonychia (odds ratio = 17.6, confidence interval = 3.0-104.0, P = 0.002), nail plate destruction (odds ratio = 10.9, confidence interval = 2.0-59.4, P = 0.006) and polychromia (odds ratio = 5.3, confidence interval = 1.36-20.57, P = 0.016) were distinctive dermoscopic features of invasive nail unit melanoma. A predictive model with scores ranging from 0 to 6 points demonstrated a reliable diagnostic value (C-statistic = 0.902) in differentiating invasive nail unit melanoma from nail unit melanoma in situ.

CONCLUSIONS

Invasive nail unit melanoma and nail unit melanoma in situ have different dermoscopic features. A predictive model based on morphologic dermoscopic features could aid in differentiating invasive nail unit melanoma from nail unit melanoma in situ.

Melanoma of the nail apparatus: a systematic review and meta-analysis of current challenges and prognosis

Nail apparatus melanoma (NAM) is a rare dermatologic malignancy. Its prognosis is poor because it is often diagnosed late. However, progression and survival of NAM patients have only been studied among small populations. Early biopsy could help to identify suspicious lesions at a less invasive stage. While surgery is generally seen as the treatment of choice, the extent of excision margins and the use of sentinel biopsy remain debated. This systematic review aims to summarize the treatment procedures and observed prognosis in the literature during the last two decades and present pooled survival and progression rates of NAM by using meta-analysis. A systematic review on studies assessing pathology, treatment and prognosis of NAM was carried out up to end of 2018. After evaluation of eligible studies, the main emerging topics were outlined and pooled survival outcomes estimated. A total of 30 articles out of 624 identified records were included for systematic review. Finally, meta-analysis of pooled mortality rates including 18 studies was 4.6 × 100 patient-years (95% CI: 2.7, 6.8) equivalent to 5-year cumulative survival of 77.0%. Additionally, the pooled progression rate based on 17 studies was 6.3 × 100 patient-years (95% CI: 4.1, 8.9) with estimated 5-year cumulative progression-free survival of 68.5%. While the optimal extent of surgical treatment remains debated, prompt biopsy could help to identify early lesions. This is the first study to present pooled survival and progression rates by meta-analysis.

Japanese Dermatological Association Guidelines: Outlines of guidelines for cutaneous melanoma 2019

With consideration of the ongoing developments in treatment options for cutaneous melanoma, the Japanese Skin Cancer Society published the first guidelines for cutaneous melanoma in 2007 and later revised them in 2015. Here, we report on an English version of the 2019 Japanese Melanoma Guidelines. In this latest edition, all processes were carried out according to the Grading of Recommendations, Assessment, Development and Evaluation system. A comprehensive published work search, systematic review and determination of recommendations in each clinical question were performed by a multidisciplinary expert panel consisting of dermatologists, a plastic and reconstructive surgeon, and a radiation oncologist. The advent of novel agents, such as immune checkpoint inhibitors and molecular-targeted agents, has drastically changed the nature of treatment for adjuvant and advanced-stage diseases among melanoma patients worldwide. Additionally, recent reports of clinical trials regarding surgical procedures and a better understanding of molecular biology and tumor immunology in clinical types of melanoma have had an impact on clinical practise. Based on these viewpoints, eight relevant clinical questions were raised in this report that aim to help clinicians select the appropriate therapeutic approach.

Subungual Melanoma

Subungual melanoma is a rare form of melanoma that presents a unique set of challenges largely based on the complex anatomy of the nail unit. Subungual melanoma often first appears with longitudinal melanonychia. Thus, practitioners must have a high clinical suspicion in any patient with longitudinal melanonychia and a low threshold for a biopsy. The "ABCDEF" guide can be a useful tool to aid in screening any lesion of the nail bed. The authors recommend that biopsies of the nail unit be performed by a surgeon with an in-depth understanding of the pathoanatomy of subungual melanoma.

Surgical Management of Plantar Melanoma: A Retrospective Study in One Center

Cutaneous melanoma is a highly malignant skin tumor, and in China, the planta pedis is a commonly involved site. The sites of plantar melanomas are a challenge to reconstruct after wide excision. Our experience with surgical management of melanomas was based on the 4 different anatomic subunits of the planta pedis. From January 1, 2002 to December 31, 2016, 35 patients who had had plantar melanoma had undergone surgical treatment in our clinic. The tumor locations were as follows: the toe in 6, the ball of the foot in 5, the arch in 15, and the heel in 9. Surgical management involved extended resection of the tumor, repair of defects with skin grafts or flaps, and inguinal lymphadenectomy. The skin flaps included a residual toe flap, an anterograde or retrograde medial plantar flap, and a retrograde sural neurocutaneous vascular flap. Of the 35 cases of flaps and skin grafts, 33 (94.29%) survived, and the wounds had healed by first intention. After a follow-up period of 6 months to 7 years, 24 patients (68.57%) were free of local and systemic disease and 30 patients (85.71%) were ambulatory using shoes, and all the flaps and skin grafts showed a good appearance. The personalized surgical treatments we used for melanoma in the planta pedis resulted in overall satisfactory outcomes and adequate disease clearance, and allowed the patients to resume normal lives. The function of the foot was maintained or restored to the greatest possible degree, and the patients' quality of life improved postoperatively.

The Diagnosis and Treatment of Nail Disorders

BACKGROUND

Nail disorders can arise at any age. About half of all nail disorders are of infectious origin, 15% are due to inflammatory or metabolic conditions, and 5% are due to malignancies and pigment disturbances. The differential diagnosis of nail disorders is often an area of uncertainty.

METHODS

This review is based on publications and guidelines retrieved by a selective search in PubMed, including Cochrane reviews, meta-analyses, and AWMF guidelines.

RESULTS

Nail disorders are a common reason for derma - tologic consultation. They are assessed by clinical inspection, dermatoscopy, diagnostic imaging, microbiological (including mycological) testing, and histopathological examination. Some 10% of the overall population suffers from onychomycosis, with a point prevalence of around 15%. Bacterial infections of the nails are rarer than fungal colonization. High-risk groups for nail disorders include diabetics, dialysis patients, transplant recipients, and cancer patients. Malignant tumors of the nails are often not correctly diagnosed at first. For subungual melanoma, the mean time from the initial symptom to the correct diagnosis is approximately 2 years; this delay is partly responsible for the low 10-year survival rate of only 43%.

CONCLUSION

Evaluation of the nail organ is an important diagnostic instrument. Aside from onychomycosis, which is a common nail disorder, important differential diagnoses such as malignant diseases, drug side effects, and bacterial infections must be considered.

Subungual Melanoma is Not so Rare: Report of Four Cases from India

Subungual melanoma (SUM) is an uncommon form of acral melanoma that arises within the nail matrix. The incidence for acral melanomas is similar worldwide, however, the proportion is higher in dark-skinned individuals. The subungual form represents approximately 2% of cutaneous non-sun-induced melanomas in the western world and up to 75% in Africans, 10% in Japanese, and 25% in the Chinese. No specific figures are available from the Indian subcontinent; however, the authors could trace three anecdotal case reports published over the last two decades. A general reluctance to biopsy a nail lesion to confirm the diagnosis may be contributing to the missed diagnosis. We report four cases of SUM of the big toenails seen over a period of 2.5 years. They were three women and one man with an age ranging from the 4^th to 7^th decade and disease duration of 6–18 months. The lesion involved the big toe in all and two patients had liver and lymph node metastasis at the time of presentation. Awareness among dermatologists regarding clinical manifestations, high index of suspicion for acral pigmented lesions, and nail bed biopsy may help in the early diagnosis and management and can prevent mortality.

Delayed Reconstruction for the Non-Amputative Treatment of Subungual Melanoma

BACKGROUND

In cases of early stage subungual melanoma (SUM), conservative treatment with non-amputative wide excision of the nail unit and subsequent skin graft is preferred over amputation to preserve the involved digit.

OBJECTIVE

We report a series of patients with SUM treated with conservative surgery and suggest an effective supplementary treatment process.

METHODS

We retrospectively reviewed 10 patients (2 males, 8 females) who were diagnosed with in situ or minimally invasive SUM on the first biopsy and underwent non-amputative wide excision of the nail unit. All patients underwent secondary intention healing during the histopathological re-evaluation of the entire excised lesion, and additional treatment was administered according to the final report.

RESULTS

In two of 10 patients, amputation was performed because of the detection of deep invasion (Breslow thickness: 4.0, 2.3 mm) from the final pathologic results, which differed from the initial biopsy. In six patients who received delayed skin graft, the mean total time required for complete healing after secondary intention healing and the skin graft was 66.83±15.09 days. As a result of this delayed skin graft, the final scarring was similar to the original shape of the nail unit, scored between 5 and 10 on a visual analogue scale. Most patients were satisfied with this conservative surgery except one patient, who had volar portion involvement and received an interpolated flap instead of a skin graft.

CONCLUSION

Our treatment process can reduce the risk of incomplete resection and improve cosmetic outcomes in patients with SUM.

Skin cancer of the hand: current concepts

Skin cancer accounts for most hand cancers. Prompt recognition of lesions with malignant potential can lead to early treatment and decreased disease burden. Understanding the appropriate diagnostic algorithm for a given lesion facilitates accurate staging, which guides therapy. A multidisciplinary approach that includes hand surgeons, dermatologists, oncologists, and radiation oncologists is often necessary to manage advanced disease. For most invasive tumors, the primary treatment modality remains surgical excision; however, several effective nonsurgical treatments exist for management of unresectable or low-grade cancers.

Immediate Great Toe Transfer for Thumb Reconstruction After Tumor Resection: Report of 3 Cases

BACKGROUND

Modern oncologic surgery aims not only to obtain tumor-free margins but also to spare or reconstruct limb function and preserve quality of life. A negative tumor margin in the digit generally requires amputation; therefore, function is preserved with reconstruction. We report results of simultaneous ablative tumor resection and reconstruction with a great toe transfer in patients requiring surgery for aggressive benign and malignant thumb tumors.

METHODS

Between 2000 and 2009, three patients with extensive soft tissue tumors of the distal thumb underwent amputation to obtain wide negative surgical margins. In each case, an immediate trimmed toe-to-thumb transfer was performed. Results, evaluated retrospectively, included a review of perioperative complications, donor-site morbidity, oncologic status, objective functional outcomes, and subjective patient satisfaction.

RESULTS

Three patients were found with either locally aggressive benign (n = 1) or malignant (n = 2) tumors of the thumb. All patients underwent immediate reconstruction after amputation through the base of the proximal phalanx for tumor eradication. No perioperative complications were encountered, and all toes survived. Full thumb opposition and protective sensation were achieved in all patients. All patients returned to their previous occupation without functional limitations. There is no local or distant tumor recurrence. Delayed wound healing at the ipsilateral foot donor site occurred in all 3 patients. Wet-to-dry dressing changes were successful in 2 patients, whereas the third patient required full-thickness skin grafting. All patients were satisfied with their reconstruction.

CONCLUSIONS

An immediate great toe-to-thumb transfer should be considered when thumb amputation is required to satisfy adequate oncologic margins. Such a transfer provides simultaneous restoration of digit length, position, sensation, and acceptable esthetics. This procedure is technically demanding and requires an experienced microsurgical team as well as appropriate patient counseling and consent before surgery.