Lesión dermatológica en zona de tatuaje / Dermatological lesion in tattoo area

Los tatuajes representan una situación in vivo única en la que una gran cantidad de sales metálicas y tintes orgánicos permanecen en la piel durante toda la vida. Como resultado de un mayor número de tatuajes realizados, la incidencia de complicaciones cutáneas asociadas a los tatuajes ha aumentado también. En los últimos 30 años se ha evidenciado un aumento de reportes de tumores cutáneos en los tatuajes; sin embargo, muchos autores siguen considerándolo un evento fortuito. Los posibles efectos cancerígenos locales de los tatuajes siguen sin estar claros. Se cree que este efecto podría ser multifactorial y que combina traumatismo de la aguja, inflamación local crónica, factores externos como la exposición a los rayos ultravioleta (UV) y un posible efecto pro-cancerígeno de las tintas. Se necesitan estudios epidemiológicos y clínicos a gran escala para demostrar esta asociación. Se presenta un caso de un hombre de 40 años, conocido sano, quien 2 meses después de tatuarse el hombro derecho, desarrolla una lesión con características clínicas de un queratoacantoma y a quien se le realiza el diagnostico histológico de un carcinoma espinocelular bien diferenciado e invasor.

Tattoos represent a unique in vivo situation where many metallic salts and organic dyes remain on the skin for a lifetime. As a result of a greater number of tattoos performed, the incidence of skin complications associated with tattoos has increased. In addition, in the last 30 years, there has been an increment in reports of skin tumors within tattoos; however, many authors continue to consider it is a coincidental event. The possible local carcinogenic effects of tattoos remain unclear. It is believed that this effect could be multifactorial, combining needle trauma, chronic local inflammation, external factors such as an ultraviolet rays (UV) exposure and a possible pro-cancer effect of the inks. Large-scale epidemiological and clinical studies are needed to demonstrate this association. A case of a known healthy 40-year-old male is presented, in whom 2 months after a tattoo was performed on his right shoulder, he developed a lesion with clinical characteristics of a keratoacanthoma in which the histological diagnosis of a well differentiated and invasive squamous cell carcinoma was made.

Radiographic features of subungual keratoacanthomas in dogs.

Subungual keratoacanthoma (SK) is a digital neoplasm that has rarely been reported in dogs and carries an excellent prognosis following surgical removal. Radiographic features of canine SK have only been briefly discussed in two prior case reports. Both articles described extensive distal phalangeal osteolysis, a feature more commonly associated with malignant digital neoplasms (e.g., subungual squamous cell carcinoma (SCC) or melanoma). This retrospective case series aimed to further characterize radiographic findings of histologically confirmed canine SK. Seven dogs met the inclusion criteria, with a total of seven affected digits. All seven digits (100%) had osteolysis of the distal phalanx's ungual process and crest, as well as regional soft tissue swelling. Osteolysis of the ungual process was severe in all cases, with complete destruction in six of seven digits (86%). Partial ungual crest geographic and expansile osteolysis was noted in four of seven digits (57%), while two digits (28%) had complete ungual crest destruction. Seven of seven digits (100%) had a radiographically thickened claw, and two of seven digits (28%) had associated lysis of the distal aspect of the middle phalanx. Based on these findings, an osteolytic subungual mass should not be considered pathognomonic for malignant neoplasia. Observing the imaging features previously described should prompt veterinarians to consider SK as a differential diagnosis.

Radiographic characteristics of canine subungual keratoacanthoma.

Subungual keratoacanthoma (SKA) is a rare benign nail bed tumor in dogs, and its radiographic characteristics have not been reported based on the authors' review of the literature. The purpose of this multicenter, retrospective, observational, descriptive study was to describe the radiographic features of SKA in dogs. Twelve dogs for a total of 12 digits with histologically confirmed SKA met the inclusion criteria. The radiographs of the manus or pes were reviewed by two veterinary radiologists and one veterinarian. The radiology reports were interpreted based on a consensus. In six dogs, there was lysis of both the middle phalanx (P2) and the distal phalanx (P3), whereas in the other six dogs, there was only lysis of P3. In all dogs with osteolysis of P2, the lysis involved the distal articular surface. Osteolysis of P3 was more severe in the ungual process than in the ungual crest in all dogs. The margins of the lytic regions of P2 and P3 were well defined and smoothly marginated in most dogs. Expansile changes in the P3 crest were observed in 83.3% (10/12 dogs), and the nail of the affected digit was enlarged and deformed in 91.6% (11/12 dogs). In summary, the radiographic features of canine SKA include severe pressure resorption of the P3 ungual process, expansile change of the P3 ungual crest, and nail enlargement and deformation. With these radiographic features, SKA should be considered as a differential diagnosis.

The diagnostic value of imaging techniques for keratoacanthoma: A review.

Keratoacanthoma (KA) is a fast-growing skin tumor with solitary KA being the most common type. KAs rarely metastasize and subside spontaneously. Although histopathology is the gold standard for the diagnosis of KA, its histopathological features are sometimes difficult to distinguish from those of other skin tumors. Imaging studies have certain advantages in the preoperative diagnosis of KA; they not only show the exact shape of the lesion but can also accurately determine the extent of the lesion. Combined with histopathological examination, these findings help establish a diagnosis. By summarizing the imaging features of KA, this article aimed to improve radiologists' understanding of the disease and help in the clinical and differential diagnosis of KA.

Dermatoscopic findings and dermatopathological correlates in clinical variants of actinic keratosis, Bowen's disease, keratoacanthoma, and squamous cell carcinoma.

Non-melanoma skin cancer (NMSC), predominantly squamous cell carcinoma (SCC) and basal cell carcinoma, is increasing worldwide. Dermatoscopy, which is one of the non-invasive diagnostic techniques, is important for early diagnosis of NMSC. In this study we aimed to determine dermatoscopic features of keratinocyte derived tumors including actinic keratosis (AK), Bowen's disease (BD), keratoacanthoma (KA), and SCC and correlate the dermatoscopic findings with pathology. A total of 242 lesions from 169 patients were included in the study and dermatoscopic and dermatopathological findings of the lesions were retrospectively studied. Revised pattern analysis was used for the dermatoscopic evaluation. Among 242 lesions, 145 were clinically flat (86 AK, 30 BD, and 29 SCC). Presence of vessels, ulceration, fiber sign, keratin mass, and blood spots decreased the probability of a lesion being AK. When the differential diagnosis was considered between KA and SCC vs AK and BD; vessel presence, ulceration, fiber sign, blood spots, white structureless, keratin, and centred vessels favored the diagnosis of KA and SCC. Our results may contribute to the determination of the lesions to be biopsied in patients with multiple AK on chronically sun damaged skin. In non-pigmented lesions when a final diagnosis cannot be established, knowledge of dermatopathologic and dermatoscopic correlation may significantly assist interpretation of dermatoscopic patterns and clues.

The first report of diagnosing of keratoacanthoma in Chinese Han patients using dermoscopy and reflectance confocal microscopy.

BACKGROUND: Keratoacanthoma (KA) is a special kind of tumor, which is regarded as a variant of squamous cell carcinoma (SCC) in some academic disciplines. But differentiating KA from SCC remains a diagnostic challenge. The noninvasive techniques dermoscopy and reflectance confocal microscopy (RCM) can provide new insights for diagnosis. OBJECTIVE: To observe the characteristics of KA under dermoscopy and reflectance confocal microscopy (RCM), in order to gain experience and reference for clinicians to facilitate earlier diagnosis. METHODS: We collected two cases of KA, which were confirmed by clinical and histopathological examination. The two cases were examined by dermoscopy and RCM, respectively. Then, we collected the microscopic characteristics of KA lesions. RESULTS: The dermoscopy features of KA are concentric circles of central crater, keratin mass, keratin scale, and polymorphic vascular pattern. The RCM features are described as refractile crust, atypical honeycomb pattern, dark center cells, large round nucleated cells, dendritic cells, and linear or round vessels traversing dermal papillae in the dermis. CONCLUSION: KA has some specific dermoscopy and RCM features, which can provide a basis for doctors to diagnose and intervene earlier.

A prospective diagnostic study on povidone-iodine retention in lesions suspected to be squamous cell carcinoma or keratoacanthoma.

BACKGROUND AND OBJECTIVES: While dermatoscopy improves diagnostic accuracy for raised nonpigmented lesions, those with white surface keratin can be problematical. We investigated whether retention of povidone-iodine by surface keratin provides a clue to benignity. METHODS: We performed a retrospective pilot study (n = 57) followed by a prospective study (n = 117) on raised nonpigmented lesions with white surface keratin. An initial dermatoscopic image was taken of each lesion, povidone-iodine was applied and another image taken. Following lavage with 70% ethanol, a third image was acquired. The percentage surface area of residual povidone-iodine staining after lavage was recorded, and the results analysed. RESULTS: The optimal cut-off point of residual staining was 80%, where values of ≤80% pointed to malignancy. At this cut-off, the OR for lesions with values ≤80% to be truly malignant in the retrospective set was 4.03 (95% CI: 2.1-7.6) and the AUC was 0.7 (95% CI: 0.62-0.78). For the prospective set, the corresponding OR was 2.3 (95% CI: 1.4-3.7) and the AUC was 0.62 (95% CI: 0.55-0.68). CONCLUSIONS: This study presents evidence that povidone-iodine retention may have a degree of efficacy in distinguishing benign from malignant keratotic lesions. Further study is warranted.

Dermoscopy improves diagnostic accuracy for clinically amelanotic nodules.

BACKGROUND/OBJECTIVES: Amelanotic nodular melanomas are notoriously difficult to diagnose and are responsible for a disproportionate burden of melanoma mortality. It is important to distinguish them from other amelanotic nodules. This study aimed to describe the dermoscopic features of a series of nodular melanomas and other amelanotic nodules and to determine whether dermoscopy improves diagnostic accuracy. METHOD: Retrospective analysis of 150 clinically amelanotic nodules with macroscopic and dermoscopic images. RESULTS: In terms of classifying the nodules as malignant, dermoscopy was superior to unaided eye (specificity 89%; 95% CI 71-98% vs 67%; 95% CI 46-83%, P = 0.03). Dermoscopy enhanced sensitivity for the diagnosis of both amelanotic melanoma and SCC. In 19% of cases, using dermoscopy, the most likely diagnosis was changed from incorrect to correct. This included 26% of amelanotic melanomas which had a macroscopic misdiagnosis overturned to the correct diagnosis. Polymorphous vascular structures were more common in malignant nodules. 76% of amelanotic melanomas/Merkel cell carcinomas had polymorphous vessels compared with 38% of SCCs/KAs/BCCs and 22% of benign nodules (P < 0.001). CONCLUSION: Dermoscopy improves diagnostic accuracy for amelanotic melanomas and other amelanotic nodules. Although dermoscopy improves diagnostic accuracy for amelanotic melanomas, these aggressive melanomas remain diagnostically difficult.

Enhancing Skin Cancer Diagnosis with Dermoscopy.

Dermoscopy increases the sensitivity for skin cancer detection, decreases the number of benign lesions biopsied for each malignant diagnosis, and enables the diagnosis of thinner melanomas compared with naked eye examination. Multiple meta-analyses have identified that dermoscopy improves the diagnostic accuracy for melanoma when compared with naked eye examination. In addition, studies have established that dermoscopy can aid in the detection of keratinocyte carcinomas. Dermoscopy triage algorithms have been developed to help novices decide when a biopsy or a referral is most appropriate. In this article, the authors illustrate the dermoscopic features that assist in identifying melanoma and keratinocyte carcinomas.

The current role of in vivo reflectance confocal microscopy within the continuum of actinic keratosis and squamous cell carcinoma: a systematic review.

BACKGROUND: Clinical differentiation between actinic keratosis (AK), squamous cell carcinoma (SCC) in situ, and invasive SCC and its variants may be difficult. Reflectance confocal microscopy (RCM) is a non-invasive technique for in vivo skin imaging. OBJECTIVES: To explicate the diagnostic and monitoring use of RCM within the spectrum of AK and SCC, and evaluate the accuracy of RCM for these diagnoses relative to histopathology. MATERIALS & METHODS: A systematic literature search was performed in PubMed, EMBASE, the Cochrane Library, and Web of Science databases. The quality was assessed using the STrengthening the Reporting of OBservational studies in Epidemiology (STROBE) checklist. RESULTS: Twenty-five eligible studies were included. Different diagnostic RCM features have been described for AK, actinic cheilitis (AC), erythroplasia of Queyrat, Bowen disease, invasive SCC, and keratoacanthoma (KA). The overall range of sensitivity and specificity of RCM for the diagnosis of SCC, AK, SCC in situ, and KA was 79-100% and 78-100%, respectively. CONCLUSION: The current literature describes the use of RCM for diagnosing AK, AC, erythroplasia of Queyrat, Bowen disease, invasive SCC, and KA, as well as for monitoring treatments of AK, with good accuracy. Unfortunately, studies with high methodological quality are lacking. Pre-treatment of hyperkeratotic lesions and uniform definitions of RCM features are required to simplify the differentiation between AKs, SCC in situ, and SCC and its variants in clinical practice.

Subungual tumors: clinicopathologic correlation with US and MR imaging findings.

Various types of tumors can affect the subungual space, including benign solid tumors (glomus tumor, subungual exostosis, soft-tissue chondroma, keratoacanthoma, hemangioma, lobular capillary hemangioma), benign cystic lesions (epidermal and mucoid cysts), and malignant tumors (squamous cell carcinoma, malignant melanoma). Imaging plays an important role in the detection and differentiation of subungual tumors because of their small size, nonspecific clinical manifestations, and functional significance. Ultrasonography (US)-in particular, high-resolution US with color Doppler studies-provides useful information regarding tumor size, location, shape, and internal characteristics (cystic, solid, or mixed), but it is limited in the further characterization of tissue. Magnetic resonance (MR) imaging has an important role in categorizing tumors according to their anatomic location, pathologic origin, and signal characteristics. There is some overlap between the US and MR imaging features of subungual tumors; however, certain features can allow accurate diagnosis and expedite management when correlated with clinical and pathologic findings.

Spontaneous regression of subungual keratoacanthoma with reossification of underlying distal lytic phalynx.

A 45-year-old man presented with a rapidly enlarging keratotic lesion of the distal subungual right middle finger. An X-ray of the digit revealed a well-defined cup-shaped lytic lesion of the phalynx underlying the subungual nodule. The lesion resolved spontaneously with reossification of the underlying bony defect. The clinical history and X-ray is consistent with a diagnosis of spontaneously resolving subungual keratoacanthoma.

Malignant changes in a giant orbital keratoacanthoma developing over 25 years.

PURPOSE: To report a patient with a history over 25 years of a slowly growing, large, invasive crateriform tumour filling the anterior part of the orbit. METHODS: A 61-year-old male presented with a large tumour of the left orbit. Exenteration was performed with subsequent histological analysis of the excised mass. RESULTS: The main tumour showed the characteristic features of a keratoacanthoma. However, the posterior aspect of the tumour disclosed the morphology of a squamous cell carcinoma. Six months later, the patient presented with metastases to lymph nodes, lung and mediastinal tissue. A leukemoid reaction was diagnosed by fine needle biopsy. CONCLUSION: The giant variety of keratoacanthoma may fail to regress and can transform into a squamous cell carcinoma. In our patient, the development of a chronic lymphoid leukemia raises the possibility that it may be the underlying cause for the transformation of the posterior part of the keratoacanthoma into a frank squamous cell carcinoma.

Subungual keratoacanthoma--a report of four cases and review of the literature.

Subungual keratoacanthoma is a rare benign neoplasm which most commonly occurs in middle-aged Caucasians. It usually presents as a painful, rapidly growing lesion of the terminal phalanx. Radiography consistently demonstrates a well-defined cup-shaped erosion of the underlying bone. Clinically, subungual keratoacanthoma must be distinguished from subungual squamous carcinoma. We report four further cases and discuss the literature.