Improvement in survival rate of patients with acral melanoma observed in the past 22 years in Sendai, Japan

More than just acral melanoma: the controversies of defining the disease

Acral melanoma (AM) is a malignant cutaneous melanocytic tumour specifically located on the palms, soles, and nail apparatus, which are areas of glabrous (hairless) skin. Acral lentiginous melanoma, a subtype of AM, represents a histopathological subtype diagnosis of cutaneous melanoma with unique morphological and structural features. Despite clear definitions, the misuse of these terms and the inconsistency in reporting the histopathological features of AM cases have become a major obstacle to the study of the disease. In this review, we discuss the epidemiology, histopathological features, prognosis, and genetic profile of AM, highlighting the differences observed when histopathological subtypes are considered. The increasing global effort to characterise AM cases from ethnically diverse populations would benefit greatly from a more consistent classification of the disease.

Local recurrence and metastasis in patients with malignant melanomas after surgery: A single-center analysis of 202 patients in South Korea

Malignant melanoma (MM) is a lethal skin cancer in Western countries. Although the incidence is low in Asians compared to that in Caucasians, it is increasing. However, literature regarding risk factors for prognosis of MM patients who have undergone surgical excision in Asian is limited. This study aimed to investigate the predictive factors for local recurrence and metastasis in MM patients who underwent surgical treatment at a single tertiary-level hospital in Korea. Patients who underwent surgery for MM at our institution between January 1998 and December 2014 were analyzed. We retrospectively investigated risk factors for local recurrence and metastasis after surgery. In cases with distant metastasis, tumor thickness (adjusted Hazard Ratio (HR), 6.139; 95% confidence interval (CI), 2.152 to 17.509; P = 0.001) and increased mitotic number [(0-1/mm² vs 2-6/mm²: adjusted HR, 4.483; 95% CI, 1.233 to 16.303; P = 0.023); (0-1/mm² vs > 6/mm²: adjusted HR, 10.316; 95% CI, 2.871 to 37.063; P < 0.001)] were associated with risk in multivariate analysis. Regarding local recurrence, tumor thickness (T4 [≥4mm] vs T1) was found to be a significant risk factor (adjusted HR, 8.461; 95% CI, 2.514 to 28.474; P = 0.001). Our data revealed tumor thickness and increased mitotic count were significant risk factors for local recurrence and distant metastasis in Korean patients with MM after surgery.

Acral melanoma detection using a convolutional neural network for dermoscopy images

Background/Purpose

Acral melanoma is the most common type of melanoma in Asians, and usually results in a poor prognosis due to late diagnosis. We applied a convolutional neural network to dermoscopy images of acral melanoma and benign nevi on the hands and feet and evaluated its usefulness for the early diagnosis of these conditions.

Methods

A total of 724 dermoscopy images comprising acral melanoma (350 images from 81 patients) and benign nevi (374 images from 194 patients), and confirmed by histopathological examination, were analyzed in this study. To perform the 2-fold cross validation, we split them into two mutually exclusive subsets: half of the total image dataset was selected for training and the rest for testing, and we calculated the accuracy of diagnosis comparing it with the dermatologist’s and non-expert’s evaluation.

Results

The accuracy (percentage of true positive and true negative from all images) of the convolutional neural network was 83.51% and 80.23%, which was higher than the non-expert’s evaluation (67.84%, 62.71%) and close to that of the expert (81.08%, 81.64%). Moreover, the convolutional neural network showed area-under-the-curve values like 0.8, 0.84 and Youden’s index like 0.6795, 0.6073, which were similar score with the expert.

Conclusion

Although further data analysis is necessary to improve their accuracy, convolutional neural networks would be helpful to detect acral melanoma from dermoscopy images of the hands and feet.

Reconstruction of large wounds using a combination of negative pressure wound therapy and punch grafting after excision of acral lentiginous melanoma on the foot

Melanoma in darker-pigmented individuals often develops in an acral lentiginous fashion on the foot. After surgical removal of a tumor at this site, repair of the wound can be challenging. This is because there is an insufficient local skin pool and lack of mobility of the skin in this area. Moreover, functional aspects such as walking and weight bearing should be considered. We performed a combination treatment of negative pressure wound therapy (NPWT) and punch grafting on 15 patients, after wide excision of acral lentiginous melanomas on the foot, and compared these to 26 patients who underwent either secondary intention healing (SIH, n = 13) or NPWT (n = 13) alone. The punch grafting with NPWT group showed significantly shorter healing times than those of the other two groups. Evaluation of completely healed wounds using the Vancouver Burn Scar Assessment Scale revealed that the punch grafting group had mean values better, or comparable, to the SIH or NPWT group in four of the five scales (except pigmentation). As for complications, only one patient developed a wound infection after punch grafting. Further, by utilizing NPWT for fixation of punch grafts, it was possible to treat all subjects as outpatients after punch grafting. These results show that a combination treatment of NPWT and punch grafting is an excellent therapeutic option for post-wide excision wounds on the feet, with significantly shortened healing times and favorable cosmetic outcomes.

Comparison of negative pressure wound therapy and secondary intention healing after excision of acral lentiginous melanoma on the foot

BACKGROUND

Melanoma in dark-skinned individuals often develops in an acral lentiginous fashion on the foot and wide excision usually results in a substantial defect. Various repair methods, including free flap, full-thickness skin graft and secondary intention healing (SIH), are used to repair these defects. Recently, use of negative pressure wound treatment (NPWT) has been shown to accelerate wound healing in different types of wound.

OBJECTIVES

To compare the functional and cosmetic results of NPWT and SIH in patients who underwent wide excision of melanomas on the foot.

METHODS

The wound defects of 22 patients after wide excision of melanoma on the foot were treated using SIH (n = 13) or NPWT (n = 9).

RESULTS

There was no significant difference in time to complete wound healing between the two groups. However, evaluation using the Vancouver Burn Scar Assessment Scale at the time of complete healing showed that the mean score of the NPWT group was significantly lower than that of the SIH group. The NPWT group also had significantly better results than the SIH group in terms of total score, vascularity and height of the scars. As for complications, no wound infection was encountered in the NPWT group, whereas eight of the 13 patients in SIH group had wound infections during the course of treatment despite frequent and meticulous aseptic dressing changes.

CONCLUSIONS

These results show that, despite the drawback of rather prolonged healing time, NPWT is an excellent therapeutic option for wounds after wide excision of melanoma on the foot, with acceptable functional and cosmetic outcomes.

Treatment and outcomes of melanoma in acral location in Korean patients

PURPOSE

A retrospective study was conducted to review the treatment and outcomes of mainly melanomas in acral location in a single institution in Korea, and to evaluate the prognostic significance of anatomic locations of the tumor.

MATERIALS AND METHODS

A retrospective review was completed on 40 patients between 2001 and 2006 to obtain pertinent demographic data, tumor data, treatment characteristics, and follow-up data.

RESULTS

Forty melanoma patients were identified and analyzed. Of these, 18 were male and 22 were female patients and the mean age at the time of diagnosis was 55.9 years. Of the tumors, 65% were located on the hands and feet with acral lentiginous melanoma being the most common histological subtype. Univariate analysis for the overall melanoma survival revealed that the thickness of the tumor and the clinical stage have prognostic significances. The most significant factor as analyzed by a multivariate analysis was shown to be the advanced clinical stage. Acral melanomas did not show statistically significant differences in the age at diagnosis, thickness of the tumor, stage, ulceration, and survival rates compared to non-acral melanomas. There was also no significant difference in the survival rate between the patients treated by amputation versus wide local excision in acral melanomas.

CONCLUSION

In Korean melanoma patients, thickness and advanced stages are significant factors for poorer prognosis. However, the location of melanoma did not have a significant prognostic value. In treating the melanomas in acral location, local wide excisions resulted in a similar prognosis compared to amputations.

Cutaneous melanoma in Asian-Americans

BACKGROUND

There is little information available on melanoma in non-white populations. Our objective was to characterize melanoma in Asian-Americans (AsA) and compare patient demographics and tumor characteristics with the non-Hispanic White (NHW) population.

METHODS

483,050 cutaneous melanoma patients diagnosed between 1986 and 2005 were identified using the National Cancer Data Base (NCDB); 1,237 were AsA, and 409,564 were NHW. Age, gender, site, histologic type, tumor thickness, AJCC stage, and survival were compared.

RESULTS

AsA were more likely to be diagnosed with acral lentiginous tumors (6.7%) than NHW (0.8%, P < 0.001). A greater proportion of AsA were diagnosed with T4 tumors (15.6%) than NHW (8.5%, P < 0.001). AsA presented with fewer early stage I-II tumors and more late stage III-IV tumors than NHW (P < 0.001). Survival was similar for AsA and NHW.

CONCLUSIONS

This is the largest study to date on melanoma in AsA. Compared to NHW, AsA are more likely to have acral lentinginous tumors, thick tumors, and higher stage. Despite this, their survival is similar to the NHW population.

Malignant melanoma in Taiwan: a prognostic study of 181 cases

This study was performed to determine the characteristics and clinical outcome of patients with cutaneous malignant melanoma in Taiwan. The medical records of patients with primary cutaneous melanoma between 1992 and 2001 at Chang Gung Memorial Hospital (CGMH) were retrieved from the cancer registry. Survival was analysed by the Kaplan-Meier method. Univariate and multivariate analyses of factors associated with survival were performed using the Cox proportional hazard model. One hundred and eighty-one cases were retrieved from the cancer registry of CGMH. The male to female ratio was 1 : 1.13. The most common age of onset was the sixth decade. The median age of onset was 61 years (2-95 years). There were 105 cases (58%) of acral lentiginous melanoma (ALM), 55 cases (30.4%) of nodular melanoma (NM), 19 cases (10.5%) of superficial spreading melanoma (SSM) and two cases (1.1%) of lentigo maligna melanoma. The median survival of the 181 patients was 3.71 years, and the 5-year survival rate was 45.63%. Five-year survival rates of patients with stages I, II, III and IV disease were 84.39%, 56.03%, 34.7% and 0%, respectively. Sex, Breslow thickness, Clark's level, pathological type and age were significant prognostic factors. There were no survival differences between ALM and NM. Both ALM and NM were associated with a poor prognosis when compared with SSM. In conclusion, ALM is the most common type of cutaneous malignant melanoma in Taiwan. The prognostic factors in Taiwan are similar to those in melanoma-prevalent countries.

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.

Plantar malignant melanoma -- a challenge for early recognition

The incidence of malignant melanoma has been continuously increasing over the last few decades. Non-plantar melanomas are nowadays usually diagnosed and treated surgically at an early stage. In contrast, melanoma in a plantar location is usually diagnosed at an advanced tumour stage, conferring a poor prognosis. To discover the reasons for this remarkable difference in recognition and prognosis, we analysed our cases of plantar malignant melanoma in a retrospective study. From 1990 to 1997, we treated 925 melanoma patients. Of these, 68 cases (7%) were classified as plantar melanoma. For non-plantar melanoma patients the mean age was 52.6 years, the mean Clark level was 2.8 and the mean tumour depth was 1.22 mm. In contrast, the mean age of patients with plantar melanoma was 63.3 years, the mean Clark level was 3.61 and the mean tumour depth was 2.55 mm. The mean time between the first observation of the plantar skin lesion and the first consultation with a physician (patients' delay) was 4.8 years and, on average, it took an additional 7 months before adequate surgical treatment was performed (physicians' delay). The prognosis of our patients was poor. In 98.5% (n = 67) further metastases were observed on follow-up. Since there is still no cure for advanced plantar malignant melanoma, the early detection and subsequent surgical treatment of plantar melanoma is decisive for the prognosis. Based on our results, the poor survival can be improved by a significant reduction in the time period between the first observation of a plantar skin lesion and surgical treatment. Therefore there is an urgent need for special preventive health care campaigns to reduce significantly both the patients' and the physicians' delay.

Epidemiology and prognosis of plantar melanoma in 62 Japanese patients over a 28-year period

BACKGROUND

The plantar surface is one of the commonest sites of malignant melanoma in the Japanese; however, the biological behavior is not sufficiently clarified, because of the paucity of long-term studies. We attempted an epidemiologic survey of the cases of plantar melanoma treated in our institute to study the survival rate in the recent period.

METHODS

Of the 207 cases of malignant melanoma observed over the past 28 years, 62 patients were diagnosed as having plantar melanoma. The proportion of plantar melanoma to all melanomas, the sex and age of the patients, and the histologic type, stage, and prognosis were evaluated by comparing those registered in the first half (1969-1982) and the second half (1983-1996) of the period.

RESULTS

The proportions of plantar melanoma in the first and second half periods were 31% (28 out of 90) and 29% (34 out of 117), respectively. No sex difference in the patients was observed. The mean age of the patients was 67 years. Fifty-one lesions were histologically proven to be acral lentiginous melanoma (ALM), two were superficial spreading melanoma (SSM), and nine were nodular melanoma (NM). Of the nine NMs, eight were registered in the second half period. The heel was affected in 33 (53%), the metatarsal regions in nine (14%), the toes in six (10%), and the arch areas in 14 (23%). The proportion of the weight-bearing areas, including the heel, metatarsal areas, and toes, decreased in the second half period. A comparison of the stages of plantar melanoma showed that, in the first half period, there were 18% of patients with stage IV disease in contrast to none in the second half period. Conversely, the proportion of stage I and II disease was 50% in the second half period, whereas it was only 39% in the first half period. The 5-year survival rates in the first and second half periods were 56% and 71%, respectively.

CONCLUSIONS

The prognosis of plantar melanoma has improved recently at our institute. The possible explanation for a trend to better survival in the second half period may be related to a decrease in stage IV disease as well as to an increase in the frequency of diagnosis of early stage disease.

Superficial spreading melanoma arising in a longstanding melanocytic nevus on the sole

In Asians, the plantar surface is the commonest site for cutaneous melanoma, and most melanomas arising in this region are the acral lentiginous type. Herein we describe a rare case of superficial spreading melanoma arising in a longstanding melanocytic nevus on the sole of a Korean.

Melanoma of the hand

Melanomas of the hand are relatively rare, and much confusion exists concerning their pathology and treatment. We reviewed our experience with 39 patients diagnosed with melanoma of the hand. The data were categorized by site, histology, and type of treatment. Most primaries were on the digits, with a few tumors arising on the palm. The most common histology was superficial spreading melanoma, even in the subungual location. Acral lentiginous melanoma accounted for only 8 of 39 cases. Most patients could be treated without radical amputations, even for melanomas on the digits. Review of our patients emphasized the need for early diagnosis. Biopsy of all unexplained pigmented lesions on the hands can lead to early diagnosis, relatively nondeforming treatment, and good survival.

Nodular melanoma in 62 Japanese patients: influence of initial surgical treatment on local recurrence and prognosis

The incidence of malignant melanoma is much lower in Japanese than in Caucasians, and the commonest type of melanoma in Japanese is acral lentiginous melanoma (ALM). In contrast to the improved prognosis noted in ALM, it is now of increasing concern that there is a rise in both the frequency and mortality of nodular melanoma. During the 25 years from 1970 to 1994, we observed 190 patients with melanoma, including 62 nodular melanomas and 96 ALM, at the Department of Dermatology, Tohoku University Hospital, Sendai, Japan. We retrospectively reviewed the recurrence and survival rates of nodular melanoma observed. The proportion of nodular melanoma, once comprising only 24% of all melanomas, showed a sharp increase to 40% after 1982. The anatomical sites of the primary tumor were the hands and feet (29%), extremities excluding hands and feet (27%), head and neck (23%), and trunk (21%). Comparison of the stages of nodular melanoma when diagnosed showed that the proportion of stage III remained highest throughout the whole period, but that of stage II melanomas increased after 1982. After treatment, local recurrence occurred far more frequently in nodular melanoma (19%) than in ALM (1%). The prognosis of nodular melanoma was also less favorable than that of ALM, although it slightly improved after 1982; the 5-year survival rates before and after 1982 were 34 and 50%, respectively. Twenty-eight patients with nodular melanoma had underwent simple excision or incisional biopsy of the primary tumor at another institution and were later referred to us for further intensive care or for the treatment of local recurrence and/or metastases.(ABSTRACT TRUNCATED AT 250 WORDS)