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Automated region of interest detection in histopathological image analysis is a challenging and important topic with tremendous potential impact on clinical practice. The deep learning methods used in computational pathology may help us to reduce costs and increase the speed and accuracy of cancer diagnosis. We started with the UNC Melanocytic Tumor Dataset cohort which contains 160 hematoxylin and eosin whole slide images of primary melanoma (86) and nevi (74). We randomly assigned 80% (134) as a training set and built an in-house deep learning method to allow for classification, at the slide level, of nevi and melanoma. The proposed method performed well on the other 20% (26) test dataset; the accuracy of the slide classification task was 92.3% and our model also performed well in terms of predicting the region of interest annotated by the pathologists, showing excellent performance of our model on melanocytic skin tumors. Even though we tested the experiments on a skin tumor dataset, our work could also be extended to other medical image detection problems to benefit the clinical evaluation and diagnosis of different tumors.
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Key Clinical Message: Pilomatricoma, a rare benign skin tumor arising from hair follicle matrix cells, warrants consideration in the evaluation of subcutaneous nodules or masses, especially when presenting as painless and firm lesions. Accurate diagnosis hinges on histopathological examination, underscoring the significance of clinician vigilance and prompt intervention. Abstract: Pilomatricoma, also referred to as Pilomatrixomas or Calcifying epithelioma of Malherbe, is a rare benign skin tumor derived from hair follicle matrix cells, presents a diagnostic challenge due to its diverse clinical manifestations. Females are more commonly affected by Pilomatricoma. This condition typically manifests as a painless, firm, and slowly progressive lesion. Histopathological analysis shows characteristic findings, such as basaloid cells at the periphery and shadow cells centrally. Immunohistochemical studies assess the expression of cytokeratin's associated with hair matrix differentiation. Complete surgical excision remains the cornerstone of treatment, ensuring favorable outcomes and minimizing the risk of recurrence. Awareness of this entity among clinicians is essential for timely recognition and appropriate intervention. In this specific case-study, we present a case of Pilomatricoma situated in the lower left orbital region of a 32-year-old male individual who had been noticing swelling in that vicinity over the preceding 7 months.
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Primary cutaneous adenoid cystic carcinoma (PCACC) is a rare, slow-growing adnexal skin tumor with about 250 documented cases. We present a case involving a 66-year-old woman who was treated with ovulation inductors 30 years ago and underwent surgeries for meningioma 20 years ago and invasive galactophoric adenocarcinoma of the left breast 12 years ago. She presented with a gradually enlarging, solid, skin-colored tumor on her scalp, located along an old surgical scar initially diagnosed as a keloid by her surgeon. Clinical and dermoscopic evaluations suggested basal cell carcinoma or a metastatic tumor. Confocal microscopy showed deep infiltration without specific diagnostic clues. However, histopathological examination, immunohistochemistry, and comprehensive investigations confirmed the diagnosis of PCACC. A wide local excision was performed, with no recurrence noted during the two-year follow-up. This case highlights the challenges of diagnosing PCACC through clinical, dermoscopic, and confocal methods. Histological analysis remains essential, particularly to distinguish it from metastatic lesions, emphasizing the need for a thorough diagnostic approach in such cases.
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Pilomatrixoma, also known as calcifying epithelioma of Malherbe, is a rare benign skin tumor originating from hair follicle matrix cells. It typically presents as a firm, painless subcutaneous nodule, most commonly found in the head, neck, and upper extremities. Pilomatrixoma can occasionally appear in atypical locations, posing a diagnostic challenge due to its nonspecific clinical presentation. A 43-year-old female presented with a painless, slowly enlarging mass on the lateral side of her left ankle, which had been present for approximately one year. Physical examination revealed a firm, well-circumscribed subcutaneous nodule measuring about 2 cm in diameter with normal overlying skin. An MRI of the left ankle demonstrated a well-circumscribed, subcutaneous mass with heterogeneous signal intensity, consistent with calcifications, suggesting pilomatrixoma. A fine-needle aspiration biopsy confirmed the presence of basaloid cells, shadow cells, and areas of calcification. The lesion was surgically excised, and histopathological examination validated the diagnosis of pilomatrixoma. The patient had an uneventful postoperative course, with no recurrence at the six-month follow-up. This case underscores the importance of considering pilomatrixoma in the differential diagnosis of subcutaneous nodules, even in unusual locations. A comprehensive diagnostic approach, including clinical evaluation, imaging, and histopathological examination, is essential for an accurate diagnosis. Surgical excision with clear margins is the treatment of choice, ensuring low recurrence rates and excellent patient outcomes. This report enhances the understanding of pilomatrixoma and highlights the necessity for a multimodal diagnostic strategy in managing this rare condition effectively.
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BACKGROUND: Skin neoplasms, particularly basal cell carcinoma (BCC) and squamous cell carcinoma (SCC), are prevalent forms of skin malignancies. To enhance accurate diagnosis, non-invasive techniques including high-frequency ultrasound (HFUS) are crucial. HFUS offers deeper penetration compared to reflectance confocal microscopy (RCM), and optical coherence tomography (OCT), making it valuable for examining skin structures. The aim of this study was to investigate and diagnose localized manifestation of BCC and SCC with HFUS and compare it with pathology results in patients referred to Razi Hospital, Tehran, Iran. METHOD AND MATERIALS: This study included patients diagnosed with BCC and SCC, with clinical and pathological confirmation, attending the oncology clinic of Razi Hospital, Tehran, Iran, from 2022 to 2023. Exclusion criteria comprised metastatic and recurrent cases, patients who underwent treatment or surgery, and tumors located in anatomically challenging areas. HFUS with a 20 MHz probe and Doppler ultrasound were employed to examine the skin. Tumors were subsequently excised, fixed in formalin, and sent for pathological assessment. Ultrasound findings were compared with pathology results. RESULTS: The study assessed 40 patients, with half diagnosed with SCC and the other half with BCC. The majority of SCC patients were male (80%), while BCC patients were relatively evenly divided between males (65%) and females (35%). The mean age was 59.15 ± 11.9 years for SCC and 63.4 ± 8.9 years for BCC. Cheeks (20%) and lips (35%) were the most common sampling sites for BCC and SCC, respectively. The correlation coefficients for tumor size and depth between ultrasound and pathology were 0.981 and 0.912, respectively, indicating a high level of agreement between the two methods. CONCLUSION: In BCC patients, there was complete agreement between sonographic loco-regional extension and pathology findings. However, some discordance (30%) was observed in SCC cases. The study demonstrated a strong correlation between ultrasound and pathology in accurately detecting the depth and extent of the tumor. However, due to the inclusion of only patients with positive pathology, it is not appropriate to evaluate the diagnostic test values and compare them with pathology results. Therefore, it is highly recommended to carry out additional studies with larger sample sizes to further validate these findings.
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Carcinoma Basocelular , Carcinoma de Células Escamosas , Neoplasias Cutâneas , Humanos , Carcinoma Basocelular/diagnóstico por imagem , Carcinoma Basocelular/patologia , Neoplasias Cutâneas/diagnóstico por imagem , Neoplasias Cutâneas/patologia , Carcinoma de Células Escamosas/diagnóstico por imagem , Carcinoma de Células Escamosas/patologia , Feminino , Masculino , Pessoa de Meia-Idade , Idoso , Ultrassonografia/métodos , Adulto , Idoso de 80 Anos ou mais , Irã (Geográfico)RESUMO
Correlative imaging of cutaneous tumors provides additional information to the standard histopathologic examination. However, the joint progress in the establishment of analytical techniques, such as Laser-Induced Breakdown Spectroscopy (LIBS) and Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) in clinical practice is still limited. Their combination provides complementary information as it is also shown in our study in terms of major biotic (Ca, Mg, and P) and trace (Cu and Zn) elements. To elucidate changes in the elemental composition in tumors, we have compiled a set of malignant tumors (Squamous Cell Carcinoma, Basal Cell Carcinoma, Malignant Melanoma, and Epithelioid Angiosarcoma), one benign tumor (Pigmented Nevus) and one healthy-skin sample. The data processing was based on a methodological pipeline involving binary image registration and affine transformation. Thus, our paper brings a feasibility study of a practical methodological concept that enables us to compare LIBS and LA-ICP-MS results despite the mutual spatial distortion of original elemental images. Moreover, we also show that LIBS could be a sufficient pre-screening method even for a larger number of samples according to the speed and reproducibility of the analyses. Whereas LA-ICP-MS could serve as a ground truth and reference technique for preselected samples.
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INTRODUCTION AND IMPORTANCE: Seborrheic keratosis (SK) is a common benign epidermal tumor usually presenting as small, non-pigmented lesions on the skin. However, giant SK presenting as a pigmented variant is a rare occurrences, with limited documented cases in medical literature. CASE PRESENTATION: Here, we present a case report of a 70 year old female patient with an unusual giant warty cutaneous lesion prompting excisional biopsy. Histopathological examination revealed pigmented proliferative basaloid cell and pseudohorn cysts, characteristic of SK. Notably, the lesion exhibited pigmentation, adding to the rarity of the giant forms of SK case. CLINICAL DISCUSSION: Giant pigmented seborrheic keratosis (GPSK) is an uncommon form that shares clinical and dermatoscopic features, frequently causing misdiagnosis as malignant melanoma. CONCLUSION: Thus this report underscores the importance recognizing such atypical presentations of SK and highlights the need for histological evaluation to diagnose such variants.
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Hidradenoma papilliferum (HP) is a benign adnexal tumor, commonly affecting the anogenital region of middle-aged women. Clinically, HP typically presents as a slow-growing, unilateral, well-circumscribed, smooth skin-colored cystic dermal nodule, usually growing less than 1 cm in size. Reports of ectopic HP are exceedingly rare but have been identified in areas containing modified apocrine gland structures, most commonly on the head and neck, and have included ceruminous glands of the external ear canal, the Moll glands of the eyelid, mammary glands of the breast, maxillofacial region and areas on the scalp. To the best of our knowledge, there is only one case of ectopic HP located on the external ear canal reported in English literature. We present a second case of draining ectopic HP located on the conchal bowl of the external ear canal.
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Automated region of interest detection in histopathological image analysis is a challenging and important topic with tremendous potential impact on clinical practice. The deep-learning methods used in computational pathology may help us to reduce costs and increase the speed and accuracy of cancer diagnosis. We started with the UNC Melanocytic Tumor Dataset cohort that contains 160 hematoxylin and eosin whole-slide images of primary melanomas (86) and nevi (74). We randomly assigned 80% (134) as a training set and built an in-house deep-learning method to allow for classification, at the slide level, of nevi and melanomas. The proposed method performed well on the other 20% (26) test dataset; the accuracy of the slide classification task was 92.3% and our model also performed well in terms of predicting the region of interest annotated by the pathologists, showing excellent performance of our model on melanocytic skin tumors. Even though we tested the experiments on the skin tumor dataset, our work could also be extended to other medical image detection problems to benefit the clinical evaluation and diagnosis of different tumors.
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The diagnosis of malignant melanoma, often an inconspicuous but highly aggressive tumor, is most commonly done by histological examination, while additional diagnostic methods on the level of elements and molecules are constantly being developed. Several studies confirmed differences in the chemical composition of healthy and tumor tissue. Our study presents the potential of the LIBS (Laser-Induced-Breakdown Spectroscopy) technique as a diagnostic tool in malignant melanoma (MM) based on the quantitative changes in elemental composition in cancerous tissue. Our patient group included 17 samples of various types of malignant melanoma and one sample of healthy skin tissue as a control. To achieve a clear perception of results, we have selected two biogenic elements (calcium and magnesium), which showed a dissimilar distribution in cancerous tissue from its healthy surroundings. Moreover, we observed indications of different concentrations of these elements in different subtypes of malignant melanoma, a hypothesis that requires confirmation in a more extensive sample set. The information provided by the LIBS Imaging method could potentially be helpful not only in the diagnostics of tumor tissue but also be beneficial in broadening the knowledge about the tumor itself.
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Lasers , Magnésio , Melanoma , Neoplasias Cutâneas , Análise Espectral , Humanos , Melanoma/patologia , Melanoma/diagnóstico por imagem , Melanoma/diagnóstico , Melanoma/química , Análise Espectral/métodos , Magnésio/análise , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/diagnóstico por imagem , Cálcio/análiseRESUMO
We report an near-infrared (NIR)-trackable and therapeutic liposome with skin tumor specificity. Liposomes with a hydrodynamic diameter of â¼20 nm are tracked under the vein visualization imaging system in the presence of loaded paclitaxel and NIR-active agents. The ability to track liposome nanocarriers is recorded on the tissue-mimicking phantom model and in vivo mouse veins after intravenous administration. The trackable liposome delivery provides in vitro and in vivo photothermal heat (â¼40 °C) for NIR-light-triggered area-specific chemotherapeutic release. This approach can be linked with a real-time vein-imaging system to track and apply area-specific local heat, which hitchhikes liposomes from the vein and finally releases them at the tumor site. We conducted studies on mice skin tumors that indicated the disappearance of tumors visibly and histologically (H&E stains). The ability of nanocarriers to monitor after administration is crucial for improving the effectiveness and specificity of cancer therapy, which could be achieved in the trackable delivery system.
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Raios Infravermelhos , Lipossomos , Paclitaxel , Medicina de Precisão , Neoplasias Cutâneas , Lipossomos/química , Animais , Camundongos , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/terapia , Paclitaxel/química , Paclitaxel/administração & dosagem , Paclitaxel/farmacologia , Teste de Materiais , Materiais Biocompatíveis/química , Tamanho da Partícula , Humanos , Sistemas de Liberação de Medicamentos , Ensaios de Seleção de Medicamentos AntitumoraisRESUMO
Distinct solitary dermal nodules, either covered by an alopecic, or sometimes ulcerated, epidermis, were noticed on the head of a stillborn Holstein calf. The head was submitted for autopsy, and the nodules were found to consist of homogeneous, diffuse pale-yellow, soft-tissue masses with distinct margins that elevated the epidermis above the adjacent skin. Histologically, the dermal nodules were well-delineated on the deep margin approaching the cutaneous muscle and consisted of perivascular neoplastic infiltrates of round cells that in some places coalesced into sheets that extended into the dermis and subcutis. Neoplastic cells separated adnexa and collagen. Immunohistochemistry revealed intense tumor cell expression of vimentin, Iba1, E-cadherin, and CD204; expression of CD18 was faint. The masses were diagnosed as Langerhans cell histiocytosis. Congenital cutaneous Langerhans cell histiocytosis has not been reported previously in cattle, to our knowledge, and should be included in the differential diagnosis of congenital nodular skin lesions.
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Doenças dos Bovinos , Histiocitose de Células de Langerhans , Bovinos , Animais , Doenças dos Bovinos/patologia , Doenças dos Bovinos/congênito , Doenças dos Bovinos/diagnóstico , Histiocitose de Células de Langerhans/veterinária , Histiocitose de Células de Langerhans/patologia , Histiocitose de Células de Langerhans/diagnóstico , Histiocitose de Células de Langerhans/congênito , Feminino , Dermatopatias/veterinária , Dermatopatias/patologia , Dermatopatias/diagnósticoRESUMO
Pilomatrixoma or pilomatricoma is a benign adnexal neoplasm originating from the hair matrix, the inner sheath of the hair follicle, and the hair cortex. Although it is considered rare in adults, numerous cases have been documented in the literature. We present a case of an elderly male who sought consultation due to a newly appearing nodular lesion on his left forearm. Several benign and malignant entities were included in the original differential diagnosis. High-frequency ultrasonographic features suggested a cystic neoplasm with calcification and mild intralesional vascularity. Ultimately, histopathological examination confirmed the diagnosis of pilomatricoma. In this study, our aim is to review the importance of the available diagnostic tools, such as dermoscopy, and the emerging utility of cutaneous high-frequency ultrasonography. Some rarer pathological variants are also discussed, including perforating, anetodermic, bullous and pigmented pilomatricoma. We hope that exposure to these clinical, dermoscopic, ultrasonographic, and histopathological images will encourage clinicians to consider pilomatricoma in their differential diagnosis when approaching nodular lesions, regardless of location and patient's age.
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Malignant sweat gland tumors are very rare. Hidradenocarcinoma is an uncommon malignancy arising from the intradermal ductal epithelium of eccrine sweat glands, usually in the sun-exposed parts of the body. It usually arises de novo but may develop from a benign hidradenoma. The diagnosis of hidradenocarcinoma is clinically challenging as it presents with varied consistency and clinically mimics other skin lesions such as chronic sebaceous cysts or epidermoid cysts. Hidradenocarcinoma is a highly aggressive tumor with a tendency for regional and distant spread. It is difficult to treat hidradenocarcinoma as it has high rates of morbidity and mortality and a very high incidence of recurrence. Here, we report a rare case of a 45-year-old woman who presented with a recurrent lump over the left arm diagnosed as primary hidradenocarcinoma.
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Cutaneous mast cell tumors are rarely reported in cattle. Although mutations in the c-KIT gene have been shown to play a central role in the oncogenesis of canine mast cell tumors, few data are available in cattle. This report describes the clinical, histologic, immunohistochemical, and genetic features of a multicentric cutaneous mast cell tumor in an adult cow. An 11-year-old Prim'Holstein cow was presented for a 5-month history of multiple skin nodules. Cytologic and histologic analyses of the nodules led to a diagnosis of mast cell tumors. Immunohistochemical analysis for KIT expression showed a moderate to strong signal in neoplastic mast cells with a cytoplasmic and membranous pattern. Sequencing of the c-KIT gene coding sequence revealed no mutation. Despite partial response after corticosteroid treatment, euthanasia was elected. No metastases to the lymph nodes, spleen, and liver were identified at post-mortem and histologic examinations.
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Doenças dos Bovinos , Doenças do Cão , Mastocitoma Cutâneo , Neoplasias Cutâneas , Feminino , Bovinos , Animais , Cães , Mastócitos/patologia , Doenças do Cão/diagnóstico , Neoplasias Cutâneas/veterinária , Mastocitoma Cutâneo/patologia , Mastocitoma Cutâneo/veterinária , Mutação , Proteínas Proto-Oncogênicas c-kit/genética , Proteínas Proto-Oncogênicas c-kit/metabolismo , Doenças dos Bovinos/patologiaRESUMO
INTRODUCTION: Malignant non-melanoma skin cancers (NMSC) are of two main types: basal cell carcinoma (BCC) and squamous cell carcinoma (SCC). In rare occasions, some of the malignant skin lesions show histopathological characteristics of both BCC and SCC and are known as basosquamous carcinomas (BSC). In some cases of large tumors, extensive reconstructive surgery might be needed to correct the skin defect after the primary excision. PRESENTATION OF CASE: We report a case of a 76-year-old Bulgarian male patient who presented with a neglected giant cutaneous tumor with more than a 15-year history of a growing mass in the right deltoid area. On physical exam an enormous exophytic ulcerated and crusted skin lesion measuring around 11×11cm was found. Wide local excision of the lesion with 10-mm resection margins and partial resection of the underlying deltoid muscle were performed due to signs of infiltration. A full-thickness total skin graft from the left inguinal area was harvested to cover the skin defect. Final histopathological examination showed metatypical carcinoma with mixed characteristics of SCC and BCC - BSC, with infiltration of the fatty tissue, deltoid muscle and clear margins of resection, staged as T4R0. Two and a half years after surgery there are no signs of upper arm motor dysfunction and no evidence of local recurrence and distant metastasis on a follow-up PET/CT. DISCUSSION: Following current National Comprehensive Cancer Network's guidelines for primary treatment of BCC, surgical candidates should undergo standard excision with wider surgical margins, postoperative margin assessment and second intention healing, linear repair, or skin graft. Therapeutic strategy for non-operable cases includes administration of radiotherapy or system therapy in the face of Hedgehog pathway inhibitors and programmed cell death protein 1 inhibitor. They can provide an alternative solution to unresectable or difficult-to-treat locally advanced cases of BSC. CONCLUSION: Similarly to BCC and SCC, the first-line treatment option for BCS is surgical excision, but surgical margins should be wider than those for low-risk BCC due to the infiltrative growth pattern of this tumor. Favorable esthetic outcome requires precise planning of the reconstructive technique.
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Carcinoma Basocelular , Carcinoma de Células Escamosas , Melanoma , Neoplasias Cutâneas , Masculino , Humanos , Idoso , Margens de Excisão , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Proteínas Hedgehog , Neoplasias Cutâneas/cirurgia , Neoplasias Cutâneas/patologia , Carcinoma Basocelular/cirurgia , Carcinoma Basocelular/patologia , Carcinoma de Células Escamosas/cirurgiaRESUMO
OBJECTIVES: To investigate whether the integration of high-frequency ultrasound (HFUS) to routine clinical examinations could improve diagnostic performance and management decision for pigmented skin tumors. METHODS: Three general practitioners trained previously and a dermatologist independently assessed pigmented skin tumors and rendered management decision based on clinical examinations alone or clinical examinations integrating HFUS. RESULTS: After integrating HFUS, the diagnostic area under the curve (AUC) (0.658-0.693 versus 0.848, all P < .05) and specificity (46.6-58.6% versus 89.7%, all P < .05) for pigmented skin malignancies were improved for general practitioners, meanwhile unnecessary biopsy rate reduced (42.9-53.6% versus 10.7%, P < .001). To the dermatologist, the diagnostic AUC (0.822 versus 0.949, P < .001), sensitivity (81.7% versus 96.7%, P = .012) and specificity (0.828 versus 0.931, P = .031) improved significantly, meanwhile both missed biopsy rate (14.5% versus 4.8%, P = .031) and unnecessary biopsy rate (19.6% versus 7.1%, P = .016) decreased. Additionally, the diagnostic performance of the general practitioner with integrating HFUS could be comparable with the dermatologist based on clinical examinations alone (all P > .05). CONCLUSIONS: As a complementary tool of clinical examinations, HFUS could help physicians differentiate pigmented skin malignancies and manage decision.
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Melanoma , Neoplasias Cutâneas , Humanos , Sensibilidade e Especificidade , Neoplasias Cutâneas/diagnóstico por imagem , Neoplasias Cutâneas/patologia , Biópsia , UltrassonografiaRESUMO
BACKGROUND: Direct wound closure (side-to-side closure) for closing nasal defects, is controversially discussed. Yet, data supporting one or the other are lacking. MATERIAL AND METHOD: An explorative, partly retrospective, partly prospective observational study including 81 patients was carried out for assessment of the operative results of after direct wound closure stretching rhinoplasty. The occurrence of complications, the esthetic result and influencing factors were examined. To assess the esthetic result the patient and observer scar assessment scale (POSAS) scores of patients and observers were determined. In both scores seven values were determined (1 point normal skin, 10 points worst imaginable scar). The individual values were added to give a total value (minimum 7-maximum 70). RESULTS: After direct wound closure stretching rhinoplasty, 12 out of 81 patients (15â¯%) developed complications, in 5 cases suture dehiscence, in 5 cases cyst formation, in 4 cases a wound infection and 2 patients developed cyst formation and a wound infection. All suture dehiscences occurred on the lower third of the nose. Most of the patients were satisfied and assessed the scar with an average total value of 13.4⯱ 7.07 (minimum 7, maximum 70, nâ¯= 42). In the individual assessments pain (1.14⯱ 0.57; minimum 1, maximum 10) was rated best and scar color (2.50⯱ 1.76; minimum 1, maximum 10) was rated worst. The total assessment in the observer-POSAS was also good with 12.9⯱ 4.8 (minimum 7, maximum 70; nâ¯= 32). Elasticity was rated best (1.47⯱ 0.88; minimum 1, maximum 7) and scar pigmentation (2.34⯱ 1.54; minimum 1, maximum 7) worst. No correlations with a complication were found. CONCLUSION: Direct wound closure stretching rhinoplasty is a safe method, especially for defect coverage in the upper two thirds of the soft tissue covering the nose, which in most cases achieved a good cosmetic result.
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Cistos , Infecção dos Ferimentos , Humanos , Cicatriz/etiologia , Estudos Retrospectivos , Técnicas de Sutura/efeitos adversos , Infecção dos Ferimentos/etiologia , Cistos/etiologiaRESUMO
Primary cutaneous SMARCA4-deficient undifferentiated malignant neoplasm (SD-UMN) is a rare and recently described entity characterized by the loss of expression of the SMARCA4 (BRG1) protein, which is involved in chromatin remodeling. SD-UMN presents a diagnostic challenge due to its rarity and unique histopathological and immunohistochemical features. In this report, we present a case of primary cutaneous SD-UMN in a 67-year-old man who presented with a rapidly growing, ulcerated, and bleeding nodule on his right cheek. Histopathological examination revealed a highly cellular dermal tumor consisting of pleomorphic epithelioid cells with prominent mitotic figures and necrosis, lacking any morphological evidence of differentiation. Immunohistochemical analysis showed a complete loss of SMARCA4 and SMARCA2 expression, while INI-1 expression remained intact. p53 was diffusely expressed, and p16 was completely absent. In addition, a range of markers, including high-molecular-weight cytokeratin, p63, SOX10, INSM1, MCPyV, NKX2.2, CD99, CDX2, CD56, ERG, NUT, desmin, androgen receptor, chromogranin, CD34, and CD43 were all negative. To date, only two cases of primary cutaneous SMARCA4-deficient undifferentiated tumors have been reported in the literature. Therefore, this case report adds to the limited body of knowledge on the clinical and histopathological features of this novel entity. The report highlights the importance of considering SD-UMN in the differential diagnosis of undifferentiated cutaneous tumors.