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1.
Vestn Oftalmol ; 136(1): 56-64, 2020.
Artigo em Russo | MEDLINE | ID: mdl-32241970

RESUMO

PURPOSE: To determine signs of small choroidal melanoma with different pigmentation using enhanced depth imaging optical coherence tomography (EDI-OCT). MATERIAL AND METHODS: The study included 344 patients with small choroidal melanoma with different pigmentation examined using EDI-OCT: 1st group - pigmented melanoma (228 eyes), 2nd group - low pigmented (65 eyes), and 3rd group - amelanotic (51 eyes). RESULTS: In pigmented small choroidal melanomas - elevation of choroidal profile towards vitreous, compression of choriocapillaries with a narrow even 'belt' and a 'shadow' effect; thinning, defects in Bruch's membrane; thickening of the retina above the tumor, lobulated photoreceptors; intra- and subretinal exudate (diffuse, cystic edema, neuroepithelial detachment); defects and detachment of pigment epithelium with hyperreflective foci, disorganization of the pigment with the formation of hyperreflective foci at different retinal levels. In low-pigmented small choroidal melanomas - elevation of choroidal profile towards vitreous, visualized inner surface of the sclera, 'excavation' of the choroid, enlarged choriocapillaries, contour of tumor; thickening of the retina, accumulation of intra- and subretinal exudate (local neuroepithelial detachments); disorganization of the pigment in pigment epithelium with hyperreflective foci in the outer retinal layers. In amelanotic small choroidal melanomas - elevation of choroidal profile towards vitreous, visualized inner surface of the sclera, 'excavation' of the choroid; contouring of choriocapillaries, longitudinal hyperreflective bands in the tumoral stroma, smoothness of the Bruch`s membrane, structural losses of photoreceptors; thickening of the retina (neuroepithelial detachment, diffuse edema); uneven thickening of pigment epithelium. CONCLUSION: EDI-OCT can help identify microstructural changes in the choroid and adjacent retina in small choroidal melanomas with different degrees of pigmentation, suggesting at the early stages a more aggressive course of the tumoral process affecting the prognosis of the disease. In addition, identification of the microstructure and degree of pigmentation of initial choroidal melanomas is necessary for planning an organ-preserving treatment.


Assuntos
Neoplasias da Coroide , Melanoma , Corioide , Neoplasias da Coroide/diagnóstico por imagem , Humanos , Melanoma/diagnóstico por imagem , Retina , Estudos Retrospectivos , Tomografia de Coerência Óptica
2.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 51(2): 264-266, 2020 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-32220199

RESUMO

A 53-year-old woman was found "an occupant in the left ciliary body" two years ago and underwent the surgery of "left eye ball removal". Pathological results confirmed the diagnosis of malignant melanoma. The patient was admitted to our hospital again due to newly found heart murmur. With the combination of cardiac magnetic resonance (CMR) imaging characteristics, including high signals on T1-weighted and fat-suppressed T1-weighted images, the high signal on T2-weighted images, uneven first-pass perfusion and late gadolinium enhancement (LGE), as well as PET signal characteristics, the diagnosis of malignant melanoma cardiac metastasis was made. This case suggests that multimodality CMR, including T1-weighted, T2-weighted, first-pass perfusion, late gadolinium enhancement, and cine imaging, can be used to monitor and detect cardiac metastasis of melanoma in a relatively early stage. Therefore, we recommend a routine echocardiography screening for patients diagnosed with melanoma. In addition, CMR examinations and PET/CT may help early detection and timely intervention of melanoma cardiac metastasis, as for their good specificity in detecting, this disease in clinical practice.


Assuntos
Neoplasias Oculares , Neoplasias Cardíacas , Melanoma , Meios de Contraste , Neoplasias Oculares/diagnóstico por imagem , Neoplasias Oculares/patologia , Neoplasias Oculares/cirurgia , Feminino , Gadolínio , Neoplasias Cardíacas/diagnóstico por imagem , Neoplasias Cardíacas/secundário , Humanos , Melanoma/diagnóstico por imagem , Melanoma/secundário , Pessoa de Meia-Idade , Miocárdio , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons , Valor Preditivo dos Testes
4.
Medicine (Baltimore) ; 99(5): e19028, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32000450

RESUMO

INTRODUCTION: Anorectal malignant melanoma (AMM) is a rare and aggressive malignance with poor prognosis, yet no consensus of treatment exists to date. Abdominoperineal resection surgery (APR) is the standard treatment of anorectal malignant melanoma, capable of controlling lymphatic spread and obtaining a large negative margin for local control but it can lead to complications. Wide local excision (WLE) allows for quicker recovery and has minimal impact on bowel function (i.e., bypassing the need for a stoma). PATIENT CONCERNS: A 66-year-old male patient presented with a 2-months history of painless rectal bleeding. DIAGNOSIS: The characteristic finding from colonoscopy and magnetic resonance imaging led to a diagnosis of colorectal cancer. Immunohistochemistry analyses confirmed malignant melanoma. The tumor was classified as: HMB-45(+), S-100(+), CD117(±), PCK(-), ki-67(+, 10%). INTERVENTIONS: The patient underwent abdominoperineal resection with no other adjuvant therapy. OUTCOMES: The patient is doing well at 24 month after the operation, with no signs of recurrence. CONCLUSION: AMM is a rare malignance, and is easy to misdiagnose. The therapy approach remains controversial. Every effort should be made to ensure prompt diagnosis and to define the optimally effective standard therapy approach.


Assuntos
Melanoma/diagnóstico por imagem , Melanoma/cirurgia , Neoplasias Retais/diagnóstico por imagem , Neoplasias Retais/cirurgia , Neoplasias Cutâneas/diagnóstico por imagem , Neoplasias Cutâneas/cirurgia , Idoso , Colonoscopia , Diagnóstico Diferencial , Humanos , Imagem por Ressonância Magnética , Masculino
5.
Medicine (Baltimore) ; 99(8): e19178, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32080099

RESUMO

RATIONALE: Primary melanocytic tumors of central nerve system (CNS) are rare, primary diffuse leptomeningeal melanomatosis (PDLM), a subtype of malignant melanomas of CNS, is extremely rare,especially in pediatrics. As the clinical manifestation of PDLM is not characteristic, It is often misdiagnosed as tubercular meningitis and hemorrhage. PATIENT CONCERNS: A 13-year-old boy was admitted to our department with symptoms of recurrent headache and vomiting twice. As the brain imaging revealed a lesion located in the left temporal lobe mimicked hemorrhage, so there was a misdiagnosis of hemorrhage in first hospitalization. He was admitted again for the recurrence of the headache and vomiting. Detailed physical examination showed multiple melanin changes in the skin of the whole body which were ignored in last hospitalization. Brain imaging showed the significantly enlarged lesion in the left temporal lobe and several smaller lesions in the left parietal lobe and cerebellum which indicated metastasis. DIAGNOSIS: According to the history,physical examination and the radiological finding, the patient was diagnosed with malignant melanoma of central never system possibly. INTERVENTIONS: The patient underwent left temporal and parietal lesions total resection with a craniotomy. OUTCOMES: The diagnosis of PDLM was established according to pathological characteristics and the negative finding of positron emission tomography (PET)-computed tomography (CT) outside CNS. The patient got no further treatment for economic reasons and experienced the progression and died 5 months after operation. LESSONS: PDLM is extremely rare in CNS, as the clinical manifestation, radiological changes are not special, early diagnosis is difficult. The confirmed diagnosis is established by leptomeningeal biospy or surgical tissue. PET-CT can help differential diagnosis with metastastic leptomeningeal melanomas. The prognosis is dismal due to the inefficiency of chemotherapy or radiotherapy.


Assuntos
Melanoma/diagnóstico , Melanoma/patologia , Neoplasias Meníngeas/diagnóstico , Neoplasias Meníngeas/patologia , Adolescente , Craniotomia , Humanos , Masculino , Melanoma/diagnóstico por imagem , Melanoma/cirurgia , Neoplasias Meníngeas/diagnóstico por imagem , Neoplasias Meníngeas/cirurgia , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons
7.
Surg Clin North Am ; 100(1): 91-107, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31753118

RESUMO

In this article we provide a critical review of the evidence available for surgical management of the nodal basin in melanoma, with an aim to ensure an understanding of risks and benefits for all lymph node surgery offered to patients, and alternatives to surgical management where appropriate.


Assuntos
Linfonodos/efeitos dos fármacos , Melanoma/patologia , Neoplasias Cutâneas/patologia , Humanos , Linfonodos/diagnóstico por imagem , Metástase Linfática , Melanoma/diagnóstico por imagem , Melanoma/tratamento farmacológico , Melanoma/terapia , Ensaios Clínicos Controlados Aleatórios como Assunto , Biópsia de Linfonodo Sentinela , Neoplasias Cutâneas/diagnóstico por imagem , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/terapia
8.
PET Clin ; 15(1): 11-22, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31735298

RESUMO

The complexity of the immune response and diversity of targets challenges conventional conceptual frameworks used in selecting and monitoring treatment with immune check-point inhibitors. The limitations of anatomic imaging in assessing response have been recognized. Varying patterns of response have been recognized. These patterns have different implications for the continuation and duration of therapy. Evidence supporting the role of 18F-fluorodeoxyglucose Positron Emission Tomography/Computed Tomography as a prognostic biomarker and in characterizing response is presented. An added benefit of this approach is the ability to detect immune-related inflammatory reactions, often in advance of severe or life-threatening clinical manifestations.


Assuntos
Fluordesoxiglucose F18 , Imunoterapia/métodos , Melanoma/diagnóstico por imagem , Compostos Radiofarmacêuticos , Neoplasias Cutâneas/diagnóstico por imagem , Antineoplásicos Imunológicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Humanos , Melanoma/terapia , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons/métodos , Neoplasias Cutâneas/terapia , Resultado do Tratamento
9.
Clin Nucl Med ; 45(3): 217-219, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31876808

RESUMO

A 54-year-old woman with known chest wall melanoma (post-wide local excision) presented for imaging after a yearlong therapy with nivolumab. F-FDG PET/CT was performed 1 day after she completed the immunotherapy. Maximum intensity projection images showed bilateral relatively symmetrical uptake in the facial region. On fused PET/CT images, the uptake was seen corresponding to subcutaneous malar prominence underneath the orbits (like eye-black stripe used in sports) with subcutaneous malar calcification. Repeat PET/CT performed after 3 months revealed significant decrease in the malar uptake. Interval resolution of the uptake likely suggested this being inflammatory and secondary to immunotherapy.


Assuntos
Imunoterapia/efeitos adversos , Melanoma/diagnóstico por imagem , Melanoma/tratamento farmacológico , Nivolumabe/uso terapêutico , Feminino , Fluordesoxiglucose F18 , Humanos , Melanoma/imunologia , Pessoa de Meia-Idade , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons
10.
Medicine (Baltimore) ; 98(44): e17839, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31689874

RESUMO

INTRODUCTION: The incidence of malignant melanoma has been rising steadily over the past decades and Merkel cell carcinoma is a highly aggressive neuroendocrine skin tumor with a high mortality rate. Sentinel lymph node (SLN) biopsy is a recommended prognostic tool in primary cutaneous malignant melanomas of intermediate thickness and in all clinically node-negative Merkel cell carcinomas. The gold standard method for identification of SLNs is lymphoscintigraphy, which involves radioactive tracers. Indocyanine green-based near-infrared fluorescence imaging (NIRFI) has been also used for intraoperative SLN identification. We aim to evaluate the diagnostic sensitivity of the VisionSense VS3 NIRFI device for SNL identification. This device uses stereoscopic 3D high definition for both fluorescence and visible light imaging. Our hypothesis is that SLNs may be identified transcutaneously using fluorescent dye injections and NIRFI; therefore, obviating the need for lymphoscintigraphy in the future. METHODS AND ANALYSIS:: lymph node identification in skin malignancy using indocyanine green transcutaneously is a prospective diagnostic sensitivity study conducted at the Department of Plastic and Hand Surgery at the University Hospital Berne, Inselspital, Switzerland. The study aims at recruiting 93 patients (start date September 2017) to compare the accuracy of VisionSense VS3 camera at identifying SLNs transcutaneously with the current gold standard, lymphoscintigraphy. Moreover, a secondary objective is to determine if anatomical location of the SLN and patient factors (eg, body mass index, age) have an impact on the ability of VisionSense to detect SLNs when compared with the same gold standard. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov NCT03545334.


Assuntos
Corantes Fluorescentes , Verde de Indocianina , Imagem Óptica/instrumentação , Imagem Óptica/métodos , Linfonodo Sentinela/diagnóstico por imagem , Neoplasias Cutâneas/diagnóstico por imagem , Administração Cutânea , Adulto , Carcinoma de Célula de Merkel/diagnóstico por imagem , Carcinoma de Célula de Merkel/patologia , Humanos , Melanoma/diagnóstico por imagem , Melanoma/patologia , Estudos Prospectivos , Método Simples-Cego , Neoplasias Cutâneas/patologia
11.
J Radiol Case Rep ; 13(4): 28-37, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31565179

RESUMO

Anorectal melanoma is a rare and aggressive malignancy with a poor prognosis. Anorectal melanoma makes up approximately 1 to 3% of all anorectal malignancies. There are no known risk factors for anorectal melanoma. Patients frequently experience a delay in diagnosis due to multiple factors including nonspecific symptoms and misdiagnosis for other benign entities. Anorectal melanoma has a high potential for distant metastases and radiographic imaging plays a key role in evaluating for metastatic disease. Common sites for metastasis include pelvic lymph nodes, lungs, liver, skin, and brain. We present a case report of a 75 year old female with a history of transanal excision of primary anorectal melanoma who presented with increasing abdominal pain and distention. Computed tomography scan of the abdomen and pelvis showed metastatic disease to the peritoneum with findings of extensive peritoneal carcinomatosis, demonstrating the aggressive nature of anorectal melanoma.


Assuntos
Neoplasias do Ânus/patologia , Melanoma/secundário , Neoplasias Peritoneais/secundário , Dor Abdominal/etiologia , Idoso , Diagnóstico Diferencial , Feminino , Humanos , Imagem por Ressonância Magnética , Melanoma/diagnóstico por imagem , Melanoma/patologia , Neoplasias Peritoneais/diagnóstico por imagem , Neoplasias Peritoneais/patologia , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons , Radiografia , Tomografia Computadorizada por Raios X , Ultrassonografia
12.
Curr Top Med Chem ; 19(27): 2494-2506, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31642783

RESUMO

Melanoma is a malignant skin tumor that results in poor disease prognosis due to unsuccessful treatment options. During the early stages of tumor progression, surgery is the primary approach that assures a good outcome. However, in the presence of metastasis, melanoma hasbecome almost immedicable, since the tumors can not be removed and the disease recurs easily in a short period of time. However, in recent years, the combination of nanomedicine and chemotherapeutic drugs has offered promising solutions to the treatment of late-stage melanoma. Extensive studies have demonstrated that nanomaterials and their advanced applications can improve the efficacy of traditional chemotherapeutic drugs in order to overcome the disadvantages, such as drug resistance, low drug delivery rate and reduced targeting to the tumor tissue. In the present review, we summarized the latest progress in imaging diagnosis and treatment of melanoma using functional nanomaterials, including polymers, liposomes, metal nanoparticles, magnetic nanoparticles and carbon-based nanoparticles. These nanoparticles are reported widely in melanoma chemotherapy, gene therapy, immunotherapy, photodynamic therapy, and hyperthermia.


Assuntos
Melanoma/diagnóstico por imagem , Melanoma/terapia , Nanomedicina , Nanoestruturas/química , Antineoplásicos/uso terapêutico , Sistemas de Liberação de Medicamentos , Febre , Terapia Genética , Humanos , Imunoterapia , Fotoquimioterapia
13.
F1000Res ; 82019.
Artigo em Inglês | MEDLINE | ID: mdl-31602297

RESUMO

Innovations in ophthalmic imaging have made a profound impact on the diagnosis and treatment of ophthalmic disease. In ocular oncology, the development of optical coherence tomography with enhanced depth imaging and swept source technologies has made it possible to visualize the anatomical characteristics of retinoblastoma and uveal melanoma with a level of detail previously unobtainable on clinical exam alone. As a result, our understanding of the pathophysiology of vision loss in choroidal melanoma in particular has improved. These modalities have also helped identify fundoscopically "invisible" tumors and risk stratify pre-malignant choroidal lesions, making a strong case for their inclusion in all screening evaluations. Optical coherence tomography angiography, on the other hand, has allowed non-invasive imaging of the retinal and uveal vasculatures, providing insight into vascular changes associated with malignant transformation and vision loss following exposure to radiation. While the impact of new imaging technologies on clinical outcomes and overall survival in ocular oncology has yet to be determined, several reports cited herein offer promising results.


Assuntos
Neoplasias da Coroide/diagnóstico , Melanoma/diagnóstico por imagem , Neoplasias Uveais/diagnóstico por imagem , Corioide/diagnóstico por imagem , Corioide/patologia , Humanos , Tomografia de Coerência Óptica
14.
BMJ Case Rep ; 12(9)2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31511264

RESUMO

We report on a clinical case with haemorrhagic small bowel metastases in a malignant melanoma patient with anaemia, diagnosed using small bowel video capsule endoscopy (VCE). A 67-year-old male patient with a previous diagnosis of malignant melanoma presented with anaemia and vertigo on admission. The standard diagnostic protocol for gastrointestinal (GI) bleeding investigation including a gastroscopy, colonoscopy and small bowel capsule endoscopy, as well as abdominal sonography and a restaging protocol including chest-abdomen-pelvis CT (CAP-CT), echocardiography and ECG was applied. Gastroscopy and colonoscopy were not conclusive in determining the bleeding source. VCE provided evidence for numerous haemorrhagic small bowel metastases. The CAP-CT was unremarkable for small bowel findings. Due to a diffuse metastatic disease diagnosed in heart, brain, liver, spleen and bone metastasis, the patient was treated in a conservative/palliative manner. VCE can provide precious information about GI bleeding of unknown origin when classical diagnostic methods are non-conclusive.


Assuntos
Hemorragia Gastrointestinal/etiologia , Neoplasias do Íleo/complicações , Neoplasias do Íleo/diagnóstico por imagem , Neoplasias do Jejuno/diagnóstico por imagem , Melanoma/complicações , Melanoma/diagnóstico por imagem , Neoplasias Cutâneas/patologia , Idoso , Anemia/etiologia , Endoscopia por Cápsula , Evolução Fatal , Humanos , Neoplasias do Íleo/secundário , Neoplasias do Jejuno/secundário , Masculino , Melanoma/secundário
15.
Molecules ; 24(17)2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31470637

RESUMO

Metastatic melanoma (MM) has a poor prognosis and is attributed to late diagnoses only when metastases has already occurred. Thus, early diagnosis is crucial to improve its overall treatment efficacy. The standard diagnostic tools for MM are incisional biopsies and/or fine needle aspiration biopsies, while standard treatments involve surgery, chemotherapy, or irradiation therapy. The combination of photodynamic diagnosis (PDD) and therapy (PDT) utilizes a photosensitizer (PS) that, when excited by light of a low wavelength, can be used for fluorescent non-destructive diagnosis. However, when the same PS is activated at a higher wavelength of light, it can be cytotoxic and induce tumor destruction. This paper focuses on PS drugs that have been used for PDD as well as PDT treatment of MM. Furthermore, it emphasizes the need for continued investigation into enhanced PS delivery via active biomarkers and passive nanoparticle systems. This should improve PS drug absorption in MM cells and increase effectiveness of combinative photodynamic methods for the enhanced diagnosis and treatment of MM can become a reality.


Assuntos
Melanoma/diagnóstico por imagem , Melanoma/tratamento farmacológico , Fármacos Fotossensibilizantes/uso terapêutico , Neoplasias Cutâneas/diagnóstico por imagem , Neoplasias Cutâneas/tratamento farmacológico , Ácido Aminolevulínico/química , Ácido Aminolevulínico/farmacocinética , Ácido Aminolevulínico/uso terapêutico , Biópsia por Agulha Fina , Portadores de Fármacos/síntese química , Diagnóstico Precoce , Humanos , Indóis/química , Indóis/farmacocinética , Indóis/uso terapêutico , Luz , Metástase Linfática , Melanoma/patologia , Imagem Molecular/métodos , Nanopartículas/administração & dosagem , Nanopartículas/química , Perileno/análogos & derivados , Perileno/química , Perileno/farmacocinética , Perileno/uso terapêutico , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacocinética , Neoplasias Cutâneas/patologia
16.
Chem Biodivers ; 16(11): e1900322, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31544357

RESUMO

The synthesis of poly[N,N-bis(3-aminopropyl)glycine] (PAPGly) dendrons Gd-based contrast agents (GdCAs) via an orthogonal protection of the different functional groups and an activation/coupling strategy wherein a specific number of synthetic steps add a generation to the existing dendron has been described. The aim of this protocol is to build up two different generations of dendrons (G-0 or dendron's core, and G-1) with peripheral NH2 groups to conjugate a 1,4,7,10-tetraazacyclododecane-1,4,7-triacetic acid (DO3A) derivative and afterwards to chelate with Gd3+ paramagnetic ions. These complexes, which have a well-defined molecular weight, are of relevance to MRI as an attempt to gain higher 1 H relaxivity by slowing down the rotation of molecule compared to monomeric Gd(III) complexes used as contrast agents and to increase the number of paramagnetic centers present in one molecular structure. From the study of their water 1 H longitudinal relaxation rate at different magnetic fields (NMRD, Nuclear Magnetic Relaxation Dispersion) and by evaluating the variable temperature 17 O-NMR data we determined the parameters characterizing the water exchange rate and the rotational correlation time of each complex, both affecting 1 H relaxivity. Furthermore, these two novel PAPGly GdCAs were objects of i) an in vivo study to determine their biodistributions in healthy C57 mice at several time points, and ii) the Dynamic Contrast-Enhanced MRI (DCE-MRI) approach to assess their contrast efficiency measured in the tumor region of C57BL/6 mice transplanted subcutaneously with B16-F10 melanoma cells. The aim of the comparison of these two dendrons GdCAs, having different molecular weights (MW), is to understand how MW and relaxivity may influence the contrast enhancement capabilities in vivo at low magnetic field (1 T). Significant contrast enhancement was observed in several organs (vessel, spleen and liver), already at 5 min post-injection, for the investigated CAs. Moreover, these CAs induced a marked contrast enhancement in the tumor region, thanks to the enhanced permeability retention effect of those macromolecular structures.


Assuntos
Meios de Contraste/química , Gadolínio/química , Melanoma/química , Compostos Organometálicos/química , Animais , Meios de Contraste/síntese química , Meios de Contraste/farmacocinética , Gadolínio/farmacocinética , Humanos , Imagem por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Masculino , Melanoma/diagnóstico por imagem , Camundongos , Camundongos Endogâmicos C57BL , Estrutura Molecular , Neoplasias Experimentais/química , Neoplasias Experimentais/diagnóstico por imagem , Compostos Organometálicos/síntese química , Compostos Organometálicos/farmacocinética , Distribuição Tecidual
17.
Comput Methods Programs Biomed ; 178: 201-218, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31416550

RESUMO

BACKGROUND AND OBJECTIVE: Skin cancer is the commonest form of cancer in the worldwide population. Non-invasive and non-contact imaging modalities are being used for the screening of melanoma and other cutaneous malignancies to endorse early detection and prevention of the disease. Traditionally it has been a problem for medical personnel to differentiate melanoma, dysplastic nevi and basal cell carcinoma (BCC) diseases from one another due to the confusing appearance and similarity in the characteristics of the pigmented lesions. The paper reports an integrated method developed for identifying these skin diseases from the dermoscopic images. METHODS: The proposed integrated computer-aided method has been employed for the identification of each of these diseases using recursive feature elimination (RFE) based layered structured multiclass image classification technique. Prior to the classification, different quantitative features have been extracted by analyzing the shape, the border irregularity, the texture and the color of the skin lesions, using different image processing tools. Primarily, a combination of gray level co-occurrence matrix (GLCM) and a proposed fractal-based regional texture analysis (FRTA) algorithm has been used for the quantification of textural information. The performance of the framework has been evaluated using a layered structure classification model using support vector machine (SVM) classifier with radial basis function (RBF). RESULTS: The performance of the morphological skin lesion segmentation algorithm has been evaluated by estimating the pixel level sensitivity (Sen) of 0.9172, 0.9788 specificity (Spec), 0.9521 accuracy (ACU), along with the image similarity measuring indices as Jaccard similarity index (JSI) of 0.8562 and Dice similarity coefficient (DSC) of 0.9142 with respect to the corresponding ground truth (GT) images. The quantitative features extracted from the proposed feature extraction algorithms have been employed for the proposed multi-class skin disease identification. The proposed layered structure identifies all the three classes of skin diseases with a highly acceptable classification accuracy of 98.99%, 97.54% and 99.65% for melanoma, dysplastic nevi and BCC respectively. CONCLUSION: To overcome the difficulties of proper diagnosis of diseases based on visual evaluation, the proposed integrated system plays an important role by quantifying the effective features and identifying the diseases with higher degree of accuracy. This combined approach of quantitative and qualitative analysis not only increases the diagnostic accuracy, but also provides some important information not obtainable from qualitative assessment alone.


Assuntos
Carcinoma Basocelular/diagnóstico por imagem , Fractais , Processamento de Imagem Assistida por Computador/métodos , Melanoma/diagnóstico por imagem , Nevo/diagnóstico por imagem , Adulto , Algoritmos , Dermoscopia , Diagnóstico por Computador , Detecção Precoce de Câncer , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reconhecimento Automatizado de Padrão , Pigmentação , Reprodutibilidade dos Testes , Máquina de Vetores de Suporte
18.
Comput Methods Programs Biomed ; 178: 289-301, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31416556

RESUMO

BACKGROUND AND OBJECTIVE: Efficient segmentation of skin lesion in dermoscopy images can improve the classification accuracy of skin diseases, which provides a powerful approach for the dermatologists in examining pigmented skin lesions. However, the segmentation is challenging due to the low contrast of skin lesions from a captured image, fuzzy and indistinct lesion boundaries, huge variety of interclass variation of melanomas, the existence of artifacts, etc. In this work, an efficient and accurate melanoma region segmentation method is proposed for computer-aided diagnostic systems. METHOD: A skin lesion segmentation (SLS) method based on the separable-Unet with stochastic weight averaging is proposed in this work. Specifically, the proposed Separable-Unet framework takes advantage of the separable convolutional block and U-Net architectures, which can extremely capture the context feature channel correlation and higher semantic feature information to enhance the pixel-level discriminative representation capability of fully convolutional networks (FCN). Further, considering that the over-fitting is a local optimum (or sub-optimum) problem, a scheme based on stochastic weight averaging is introduced, which can obtain much broader optimum and better generalization. RESULTS: The proposed method is evaluated in three publicly available datasets. The experimental results showed that the proposed approach segmented the skin lesions with an average Dice coefficient of 93.03% and Jaccard index of 89.25% for the International Skin Imaging Collaboration (ISIC) 2016 Skin Lesion Challenge (SLC) dataset, 86.93% and 79.26% for the ISIC 2017 SLC, and 94.13% and 89.40% for the PH2 dataset, respectively. The proposed approach is compared with other state-of-the-art methods, and the results demonstrate that the proposed approach outperforms them for SLS on both melanoma and non-melanoma cases. Segmentation of a potential lesion with the proposed approach in a dermoscopy image requires less than 0.05 s of processing time, which is roughly 30 times faster than the second best method (regarding the value of Jaccard index) for the ISIC 2017 dataset with the same hardware configuration. CONCLUSIONS: We concluded that using the separable convolutional block and U-Net architectures with stochastic weight averaging strategy could enable to obtain better pixel-level discriminative representation capability. Moreover, the considerably decreased computation time suggests that the proposed approach has potential for practical computer-aided diagnose systems, besides provides a segmentation for the specific analysis with improved segmentation performance.


Assuntos
Diagnóstico por Computador/métodos , Reconhecimento Automatizado de Padrão , Dermatopatias/diagnóstico por imagem , Pele/diagnóstico por imagem , Algoritmos , Artefatos , Bases de Dados Factuais , Dermoscopia/métodos , Reações Falso-Positivas , Humanos , Processamento de Imagem Assistida por Computador/métodos , Melanoma/diagnóstico por imagem , Reprodutibilidade dos Testes , Neoplasias Cutâneas/diagnóstico por imagem , Processos Estocásticos
19.
S Afr J Surg ; 57(3): 44-49, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31392864

RESUMO

BACKGROUND: Accurate pre-operative staging and correct surgical selection of patients with malignant melanoma reduces unnecessary morbidity and mortality, improves distant control and may improve survival. 18F-fluorodeoxyglucose Positron Emission Tomography Computed Tomography (18F-FDG PET-CT) has been shown to be useful in exclusion of metastatic sites and aids in surgical planning in stage III and potentially resectable stage IV disease. The primary objective of the study was to determine whether the use of PET-CT alters the initial staging and management of patients with advanced and recurrent melanoma. METHOD: Retrospective analysis of clinical records of patients with malignant melanoma referred for staging PET-CT over a three-year period at our institution was performed. Pre- and post-PET-CT stage was recorded and a descriptive analysis was done to determine whether PET-CT resulted in a change in stage grouping and whether this change effected a change in clinical management. RESULTS: A change in stage grouping occurred in 21/39 (53.8%) of patients, 76.2% of which were up-staged and 23.8% down staged. On analysis of stage III/IV and recurrent melanoma, a change in stage occurred in 90% of stage III, 50% of stage IV and 50% of recurrent melanoma patients. This effected a change in management in 86.7% of patients with stage III, IV and recurrent melanoma collectively. CONCLUSION: PET-CT is a useful tool in the staging and subsequent management of melanoma. Its utility is pronounced in advanced and recurrent melanoma.


Assuntos
Melanoma/diagnóstico por imagem , Melanoma/secundário , Recidiva Local de Neoplasia/diagnóstico por imagem , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons , Neoplasias Cutâneas/diagnóstico por imagem , Neoplasias Cutâneas/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Fluordesoxiglucose F18 , Humanos , Masculino , Melanoma/terapia , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Compostos Radiofarmacêuticos , Estudos Retrospectivos , Neoplasias Cutâneas/terapia , Adulto Jovem
20.
J Surg Oncol ; 120(6): 1031-1037, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31468535

RESUMO

BACKGROUND AND OBJECTIVES: This current study assessed the value of S-100B measurement to guide fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) scanning for detecting recurrent disease in stage III melanoma patients. METHODS: This study included 100 stage III melanoma patients in follow-up after curative lymph node dissection. Follow-up visits included physical examination and S-100B monitoring. FDG PET/CT scanning was indicated by clinical symptoms and/or elevated S-100B. RESULTS: Of 100 patients, 13 (13%) had elevated S-100B without clinical symptoms, of whom 7 (54%) showed disease evidence upon FDG PET/CT scanning. Twenty-six patients (26%) had clinical symptoms with normal S-100B and FDG PET/CT revealed metastasis in 20 (77%). Three patients had clinical symptoms and elevated S-100B, and FDG PET/CT revealed metastasis in all three (100%). Overall, FDG PET/CT scanning revealed metastasis in 30 of the 42 patients (71.4%). For seven recurrences, elevated S-100B prompted early detection of asymptomatic disease; 10% of all asymptomatic patients in follow-up, 23% of all patients with recurrent disease. CONCLUSION: S-100B cannot exclude recurrent disease during follow-up of stage III melanoma. However, adding S-100B measurement to standard clinical assessment can guide FDG PET/CT scanning for detecting recurrent melanoma.


Assuntos
Biomarcadores Tumorais/metabolismo , Fluordesoxiglucose F18 , Melanoma/patologia , Recidiva Local de Neoplasia/diagnóstico , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons/métodos , Subunidade beta da Proteína Ligante de Cálcio S100/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Masculino , Melanoma/diagnóstico por imagem , Melanoma/metabolismo , Melanoma/cirurgia , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/diagnóstico por imagem , Recidiva Local de Neoplasia/metabolismo , Estadiamento de Neoplasias , Compostos Radiofarmacêuticos
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