Tumours of the foot: A 10 years retrospective analysis.

INTRODUCTION: The foot is a complex structure composed of several tissues, each of which can be the origin of the proliferation and development of the tumour. Most lesions about the foot are reactive or inflammatory, but some are true neoplasms. METHOD: This is a retrospective analysis of 4997 patient records treated in the Orthopaedic Oncology Unit of University Malaya Medical Centre, Malaysia, between 1 January 2010 to 31 December 2020. Demographic data of 195 patients with foot tumours were analysed out of 4997 neoplasm patients. RESULTS: There were 195 cases of foot tumours: 148 were benign, and 47 were malignant. 47 were bone tumours, 4 were metastases, and 144 were soft tissue tumours. Six patients succumbed to the disease, two cases of giant cell tumour (GCT) and one patient with synovial sarcoma had a recurrence. Treatment of foot tumours was wide resection in general. However, in metastasis cases, amputation was done. The majority of tumours were in the toes and dorsum of the foot. Soft tissue tumours of the foot occur in the elderly population in contrast to bone tumours, mainly in the second decade of life. The gender distribution was almost equal for foot tumours. Ganglion and Giant Cell Tumour of the bone are the commonest benign soft tissue and bone tumours. The most common malignant soft tissue and bone tumours are malignant melanoma and chondrosarcoma. The amputation rate is 5.64% the recurrence rate is 1.54%. Mortality rate is 3.08%. The MSTS score is 79%, and the TESS score is 76.23%. CONCLUSION: Foot tumours are relatively rare, mostly originating from soft tissue and exhibiting a benign nature. Nonetheless, a noteworthy proportion-approximately a quarter of these tumours-demonstrate malignancy. The surgical interventions undertaken in managing these tumours and associated functional outcomes generally yield acceptable results.

A scoring system for grading corkscrew claws in dairy cattle.

Corkscrew claw (CC) in dairy cattle is increasingly reported in dairy herds. CC is a progressive deformity of the claw capsule with uncertain aetiology and pathogenesis. Genetics and specific environmental factors are suspected of contributing to the development of this irreversible condition. CC has been found in lame cows; however, the cause and effect has not been established. To perform analysis of risk factors, treatment and pathogenesis, a definition of severity scores is called for. The aim of this study was to measure and analyse CC characteristics from photos of cows' feet to describe and evaluate a scoring system for CC. Width of the visible part of the axial wall, degree of contact between the toe and the floor and angle of the distal part of the abaxial wall as a proxy for the deviation of the abaxial wall was measured from 393 pictures of CC. Based on the measurements on the claws, the parameter "width of the axial wall" was chosen to define the scores. The parameter was divided into three intervals to define either mild CC 0.3-2.0 cm, moderate CC 2.1-3.5 cm or severe CC>3.5 cm and correlation between the parameters; level of contact between the toe and the floor and the angle of the distal abaxial wall was evaluated. There was a significant positive linear correlation between width of the axial wall and angle of the distal part of the abaxial wall (r=0.91), the wider the axial wall, the more the abaxial wall deviated in the distal part. As the width of the axial wall increased the toe increasingly lost contact with the floor, this association was significant for mild CC and moderate CC but not for severe CC. The Interobserver agreement of the CC Scoring system was tested by 30 claw trimmers each scoring 32 cadaver feet and by 2 trained observers on 28 photos of feet using Cohen´s weighted kappa and showed substantial to almost perfect agreement between untrained and trained observers, respectively.

Radiological features of arterial channels in the equine third phalanx measured using a novel customized software represent changes of laminitis.

OBJECTIVE: To identify and measure radiolucencies at the solear margin of the distal phalanx in radiographs of healthy and laminitic hooves. SAMPLE: Clinical records and dorsoproximal-palmarodistal radiographs of equine forelimbs with radiological diagnoses of either laminitis (n = 40, L) or navicular syndrome (n = 40, NS). METHODS: Outlines of the radiolucent structures at the solar margin were drawn in ImageJ, and a customized novel plugin "Arteries Analyzer/ImageJ" was used for measurements. The diverging radiolucencies outside the terminal arc of the distal phalanx were differentiated as arterial channels (open at the solear margin) and ellipses (closed at the solear margin). Comparisons between L and NS, between distal phalanges with and without ellipses, and of arterial channels and ellipses in areas were compared using Wilcoxon and the Mann-Whitney U tests, respectively. The reliability and repeatability of the method were tested using Friedman's test. RESULTS: Fewer arterial channels but more ellipses were identified in L than in NS. In phalanges with ellipses (n = 47), the number of ellipses and the number of arterial channels were negatively correlated (PCC -0.181, P = .224). The number of ellipses correlated positively with the severity of laminitis (PCC 0.495, P < .001; n = 80) and with the degree of rotation of the distal phalanx (PCC 0.392, P < .001; n = 80). CLINICAL RELEVANCE: The software tool successfully measured arterial channels and ellipses outlined by the evaluators. Results indicate that healthy arteries develop into pathological ellipses in laminitic feet. This may be used to complement the interpretation of radiographs and support clinical decision-making.

Histological comparison of the lamellar tissue of Iberian origin breed horses created in semi-feral conditions or in an intensive system.

Although the external conformation of wild horse hooves has been proposed as an ideal model for domesticated modern horses, histological signs of laminitis have been reported among them. With the hypothesis that the lamellar tissue of horses of Iberian origin raised in semi-feral is healthier than those raised in an intensive management system (stall confinement and high-calorie diet intake), the objective was to compare their lamellar tissues. Lamellar tissue samples were taken from the forelimb hoof of eight domesticated Mangalarga Marchador (MM) horses and from six semi-feral Marajoara (MJ) and Puruca (MP) horses. Primary epidermal lamella (PEL) and secondary epidermal lamella (SEL) were measured (length and width) in several regions, and their shapes were morphologically classified into different types. Breed groups were compared using analysis of variance, followed by Tukey or Dunn tests (P<0.05). Early signs of laminitis such as abnormal keratinization of the abaxial primary dermal lamella, tapered tips of the axial PELs, pointed tips of the SEL, nuclei condensation, and abnormal spatial orientation of the secondary epidermal basal cells (SELBC), were seen only in MM horses. MP horses had a greater interface of epidermis/dermis contact than MJ horses and more rounded nuclei in the round SELBC than MM horses. In agreement with the study hypothesis, semi-feral MJ and MP horses' lamellae were classified as healthier than MM horses, which showed early signs of endocrinopathic laminitis.

Osteonecrosis of the Tarsal Navicular: Not Always Spontaneous!

BACKGROUND: Mueller-Weiss disease, a rare and complex foot condition, is defined as spontaneous and progressive navicular fragmentation leading to midfoot pain and deformity. However, its exact etiopathogenesis remains unclear. We report a case series of tarsal navicular osteonecrosis to describe the clinical and imaging characteristics and etiologic profile of the disease. METHODS: This retrospective study included five women diagnosed as having tarsal navicular osteonecrosis. The following data were extracted from medical records: age, comorbidities, alcohol and tobacco consumption, history of trauma, clinical presentation, imaging modalities performed, treatment protocol, and outcomes. RESULTS: Five women with a mean age of 51.4 years (range, 39-68 years) were enrolled in the study. Mechanical pain and deformity over the dorsum of the midfoot was the main clinical presentation. Rheumatoid arthritis, granulomatosis with polyangiitis, and spondyloarthritis were reported by three patients. Radiographs revealed bilateral distribution in one patient. Three patients underwent computed tomography. It showed a fragmentation of the navicular bone in two cases.Magnetic resonance imaging was performed in one patient showing flattening of the lateral aspect of the navicular bone with signal abnormalities. Talonaviculocuneiform arthrodesis was performed in all of the patients. CONCLUSIONS: Mueller-Weiss disease-like changes may occur in patients with an underlying inflammatory disease such as rheumatoid arthritis and spondyloarthritis.

A review of cellular and molecular mechanisms in endocrinopathic, sepsis-related and supporting limb equine laminitis.

Equine laminitis has both fascinated and frustrated veterinary researchers and clinicians for many years. The recognition that many ponies suffering from pasture-associated laminitis have an insulin-dysregulated phenotype (endocrinopathic laminitis, EL) and that prolonged insulin and glucose infusions can experimentally induce laminar pathology and functional failure are seminal discoveries in this field. Researchers have studied the molecular basis for disease pathogenesis in models of EL, sepsis-related laminitis and supporting limb laminitis and generated much data over the last 15 years. This review attempts to synthesise those data, drawing comparisons between models and naturally occurring laminitis. A hypothesis is proposed that the basal epithelial cell stress is a central event in each category of laminitis. Furthermore, in naturally occurring pasture-associated laminitis, pathways that predominate in each type of laminitis contribute to laminar lamellar pathology to varying extents. Based on the molecular mechanisms determined in experimental models, interactions between these pathways are identified.

Broad-spectrum infrared thermography for detection of M2 digital dermatitis lesions on hind feet of standing dairy cattle.

Low-effort, reliable diagnostics of digital dermatitis (DD) are needed, especially for lesions warranting treatment, regardless of milking system or hygienic condition of the feet. The primary aim of this study was to test the association of infrared thermography (IRT) from unwashed hind feet with painful M2 lesions under farm conditions, with lesion detection as ultimate goal. Secondary objectives were to determine the association between IRT from washed feet and M2 lesions, and between IRT from unwashed and washed feet and the presence of any DD lesion. A total of 641 hind feet were given an M-score and IRT images of the plantar pastern were captured. Multivariable logistic regression analyses were done with DD status as dependent variable and maximum infrared temperature (IRTmax), lower leg cleanliness score and locomotion score as independent variables, and farm as fixed effect. To further our understanding of IRTmax within DD status, we divided IRTmax into two groups over the median value of IRTmax in the datasets of unwashed and washed feet, respectively, and repeated the multivariable logistic regression analyses. Higher IRTmax from unwashed hind feet were associated with M2 lesions or DD lesions, in comparison with feet without an M2 lesion or without DD, adjusted odds ratio 1.6 (95% CI 1.2-2.2) and 1.1 (95% CI 1.1-1.2), respectively. Washing of the feet resulted in similar associations. Dichotomization of IRTmax substantially enlarged the 95% CI for the association with feet with M2 lesions indicating that the association becomes less reliable. This makes it unlikely that IRTmax alone can be used for automated detection of feet with an M2 lesion. However, IRTmax can have a role in identifying feet at-risk for compromised foot health that need further examination, and could therefore function as a tool aiding in the automated monitoring of foot health on dairy herds.

The influence of equine hoof conformation on the initiation and progression of laminitis.

BACKGROUND: The health and performance of horses are significantly affected by diseases associated with the hoof. Laminitis is a critical hoof disease that causes pain and, potentially, severe hoof and bone pathology. OBJECTIVE: To generate an equine hoof finite element (FE) model to investigate the impact of normal and toe-in hoof conformations on the degeneration (decrease in elastic modulus) of the laminar junction (LJ), as occurs in chronic laminitis. STUDY DESIGN: Computer software modelling. METHODS: A hoof FE model was generated to investigate the biomechanics of hoof laminitis. A 3D model, consisting of nine components, was constructed from computed tomography scans of an equine left forelimb hoof. The model was loaded with 100 cycles of trotting. Two different centres of pressure (COP) paths representing normal and toe-in conformations were assigned to the model. LJ injury was modelled by degenerating the tissue's elastic modulus in the presence of excessive maximum principal stresses. RESULTS: FE models successfully showed findings similar to clinical observations, confirming third phalanx (P3) dorsal rotation, a symmetric distal displacement of the P3 (2 mm at the lateral and medial sides) in the normal model, and an asymmetric distal displacement of the P3 (4 mm at the lateral and 1.5 mm at the medial side) in the toe-in model. The proximal distance between P3 and the ground after LJ degeneration in the current model was significantly different from experimental measurements from healthy hooves (P < 0.01). MAIN LIMITATIONS: The inability to account for variations in population geometry and approximation of boundary conditions and system relations were the limitations of the current study. CONCLUSIONS: The distribution of LJ tissue degeneration was symmetric at the quarters in the normal hoof and in comparison, there was a lateral concentration of degeneration in the toe-in model.

HISTORIAL: La salud y el desempeño atlético de los caballos son afectados por patologías asociadas al casco. La laminitis es una enfermedad critica del casco que causa dolor y, potencialmente, patología severa del casco y ósea. OBJETIVO: Generar un modelo finito del casco equino para investigar el impacto de la conformación normal y del dedo-hacia-adentro sobre la degeneración (reducción del módulo elástico) de la unión laminar (UL), como ocurre en la laminitis crónica. DISEÑO DEL ESTUDIO: Modelado por computadora. MÉTODOS: Un modelo de elemento finito (EF) de casco fue generado para investigar la biomecánica de la laminitis en el casco. Un modelo 3D, que consistía de nueve componentes, fue construido a partir de imágenes de tomografía computarizada de un casco equino izquierdo. El modelo fue cargado con 100 ciclos de trote. Dos vías con centros de presión (VCP) distintos representando la conformación normal y dedo-hacia-adentro fueron asignadas al modelo. La lesión de la UL fue modelada degenerando el modelo elástico del tejido en la presencia de estrés principales excesivos máximos. RESULTADOS: Los modelos EF mostraron exitosamente hallazgos similares a las observaciones clínicas, confirmando que la rotación dorsal de la tercera falange (F3), con un desplazamiento distal simétrico de F3 (2 mm por medial y lateral) en el modelo normal, y un desplazamiento distal asimétrico de F3 (4 mm por lateral y 1.5 mm por medial) en el modelo dedo-hacia-adentro. La distancia proximal entre F3 y el suelo después de la degeneración de la UL en el modelo actual fue significativamente diferente de las mediciones experimentales de casco saludables (P < 0.01). LIMITACIONES DEL ESTUDIO: La inhabilidad de tomar en cuenta las variaciones en la geometría de la población y la aproximación de condiciones marginales, y relaciones de sistemas fueron las limitantes de este estudio. CONCLUSIONES: La distribución de la degeneración del tejido de la UL fue simétrico en los cuartos en el casco normal, hubo una concentración lateral de la degeneración en el modelo dedo-hacia-adentro. PALABRAS CLAVE: laminitis, conformación del casco del caballo, centro de presión, método de elemento finito, modelo hiperelástico.

Navicular bone fracture and severe deep digital flexor tendinopathy after palmar digital neurectomy in two horses.

Background: Navicular syndrome is a common cause of forelimb lameness in horses. Beyond changes to the navicular bone itself, horses with a clinical diagnosis of navicular syndrome often have pathology associated with other components of the navicular apparatus, including the navicular bursa, deep digital flexor (DDF) tendon, collateral sesamoidean ligaments, and impar ligament. Palmar digital neurectomy (PDN) is often used as a salvage procedure for horses diagnosed with navicular syndrome that become unresponsive to medical management. There are many potential complications associated with PDN, some of which are debilitating. Case Description: This report describes two cases of navicular bone fracture with severe DDF tendinopathy and distal interphalangeal joint subluxation/hyperextension that occurred 12 and 19 weeks after bilateral forelimb PDN. Conclusion: These two cases highlight the importance of proper patient selection before PDN due to the high incidence of undiagnosed soft tissue pathology in conjunction with radiographic evidence of navicular syndrome. Advanced imaging of the digit is recommended to identify and characterize any soft tissue pathology associated with the navicular apparatus before pursuing PDN to avoid disease progression and catastrophic injury.

Radiotherapy for Plantar Fibromas (Ledderhose Disease).

Ledderhose disease (plantar fibromas) is histologically related to Dupuytren disease, which has been successfully treated for years with radiotherapy. Many conservative treatments have been advanced for plantar fibromas, including accommodative orthotic devices, which help but do not cure the disease. Surgery is considered the mainstay of treatment for this malady, but the failure rate has been as high as 100%, depending on the type of fasciectomy. Radiotherapy is a new, exciting modality that has shown promising results for treating plantar fibromas.

Measurement accuracy of foot conformation parameters on low-field magnetic resonance images in horses.

Foot imbalance and malalignment of the digits are common in horses. Angle and distance measurements performed on bones, joints and hoof wall on radiographs provide essential guidance for precise corrective trimming and shoeing. This study aimed to investigate, if selected standing low-field magnetic resonance (MR) images can be used to accurately measure dorsopalmar and lateromedial foot conformation parameters in comparison to the radiographic gold standard. Images of 100 horses referred for standing low-field MR examination were selected. Foot conformation angles and distances were measured and compared between radiographs and MR images. Measurements from most imaging sources were significantly different from each other. Moderate to high correlation of foot conformation angles between radiographs and MR images in the lateromedial and dorsopalmar planes was found, with exception of the proximal interphalangeal joint angle, where there was only moderate agreement between radiographs and the 5-plane MR pilot (0.47, P < .001) and between radiographs and the 3-plane MR pilot (0.4, P < .001), respectively. Measurement of foot conformation parameters from low-field MR images should be used with caution in clinical practice and acquisition of current foot radiographs immediately before or after MR examination should be considered to facilitate precise trimming and shoeing.

From Mendel laws to whole genetic association study to decipher the swine mulefoot phenotype.

The swine mulefoot (SM) is a rare condition characterized by a non-cloven hoof due to the partial or total fusion of the phalanges. No comprehensive study has been conducted to identify associated markers with this phenotype until now. We aimed to characterize the association between SNP and the mulefoot phenotype using a Genome-Wide Association Study (GWAS). An experimental population was produced using a half-sib mating where the male had the mulefoot phenotype and the females (n = 6) had cloven hoofs. The cross resulted in 27 (47%) animals with the mulefoot characteristic and 30 (53%) normal animals, indicating the possible dominant gene action. Animals were further genotyped using the Illumina PorcineSNP50k BeadChip, and SNPs were tested for associations. Twenty-nine SNPs located on the SSC15, SSC4, and SSCX were associated with the mulefoot phenotype (p-value <5 × 10-5). Six markers were found in the intronic regions of VWC2L, CATIP, PDK3, PCYT1B, and POLA1 genes. The marker rs81277626, on SSC15:116,886,110 bp, is located in the Von Willebrand Factor C Domain (VWC2L), a possible functional candidate gene. The VWC2L is part of a biological process involved with the bone morphogenetic protein (BMP) signaling pathway, previously associated with syndactyly in other species. In conclusion, the identified markers suggest the involvement of the VWC2L gene in the SM phenotype in this population.

Objective scoring of footpad dermatitis in broiler chickens using image segmentation and a deep learning approach: camera-based scoring system.

1. Footpad dermatitis (FPD) can be used as an important indicator of animal welfare and for economic evaluation; however, human scoring is subjective, biased and labour intensive. This paper proposes a novel deep learning approach that can automatically determine the severity of FPD based on images of chicken's feet.2. This approach first determined the areas of the FPD lesion, normal parts of each foot and the background, using a deep segmentation model. The proportion of the FPD for the chicken's two feet was calculated by dividing the number of FPD pixels by the number of feet pixels. The proportion was then categorised using a five-point score for FPD. The approach was evaluated from 244 images of the left and right footpads using five-fold cross-validation. These images were collected at a commercial slaughter plant and scored by trained observers.3. The result showed that this approach achieved an overall accuracy and a macro F1-score of 0.82. The per-class F1-scores from all FPD scores (scores 0 to 4) were similar (0.85, 0.80, 0,80, 0,80, and 0.87, respectively), which demonstrated that this approach performed equally well for all classes of scores.4. The results suggested that image segmentation and a deep learning approach can be used to automate the process of scoring FPD based on chicken foot images, which can help to minimise the subjective bias inherent in manual scoring.

Surgical treatment of verrucous carcinoma: a review.

BACKGROUND: Verrucous carcinoma is a rare mucocutaneous malignancy characterized by slow, relentless growth and a low metastasis rate. OBJECTIVE: Herein we summarize surgical success rates and review newer approaches to the treatment of verrucous carcinomas. METHODS AND MATERIALS: PubMed electronic searches were performed by B.F. and C.V. using combinations of the following terms: "verrucous carcinoma," "Ackerman tumor," "Buschke Lowenstein," "epithelioma cuniculatum," "carcinoma cuniculatum," "papillomatosis cutis," "treatment," "therapeutics," "management," "mohs surgery," and "excision." A systematic review was conducted on 49 articles in accordance with PRISMA guidelines. RESULTS: Surgical management remains first-line therapy. Wide local excision is most commonly utilized, with highly variable margins (0.5-3.0 cm) and recurrence rates (4.6-75.0%). Mohs Micrographic Surgery has also been used, especially for recurrent tumors, with an overall recurrence rate of 12.9%. CONCLUSION: Surgery is the treatment of choice, either by Mohs Micrographic Surgery or wide local excision. However, surgical recurrence rates are high, and tissue-sparing therapies are desirable given the sensitive locations involved. Ultimately, randomized control trials are needed to develop evidence-based guidelines for the management of VCs.

Clinical characteristics and differences of 802 acral tumours, categorized by anatomical sites.

BACKGROUND: Acral skin tumours are common, but information in the literature regarding their incidence is scarce. AIM: To investigate the clinical characteristics and differences in incidence of benign and malignant acral tumours by anatomical site. METHODS: A retrospective review was conducted of 802 patients with acral skin tumours confirmed by skin biopsy between January 2010 and December 2019. Age, sex, duration, symptoms and sites were obtained from medical records and photographs. RESULTS: The mean age of onset was 43.8 years, the male/female ratio was 1 : 1.41, and the mean duration was 68.8 months. Most tumours were asymptomatic (66.7%). In total, 802 acral tumours were identified: 512 (63.8%) were benign and 290 (36.2%) were malignant. The most common benign tumours were benign melanocytic lesions (n = 239), and the most common malignant tumours were melanoma (n = 234). The most common site was the sole (n = 408). Benign melanocytic lesions, melanoma and epidermal cysts were more frequent on the foot, whereas pyogenic granuloma, glomus tumours, haemangiomas and mucous cysts were more frequent on the hand. Glomus tumours, fibromas, mucous cysts and osteomas were more frequent on the nail portion, and benign melanocytic lesions and epidermal cysts were more frequent on the non-nail portion. CONCLUSION: This study reports the incidence of various benign and malignant acral tumours according to site, and we believe the results will be helpful in making a clinical diagnosis.

Treatment, recurrence rates and follow-up of Tenosynovial Giant Cell Tumor (TGCT) of the foot and ankle-A systematic review and meta-analysis.

BACKGROUND: The tenosynovial giant cell tumor (TGCT) is a usually benign lesion which arises from the synovium. It affects joints, tendon sheaths and bursae. The clinical course is often unpredictable, and local recurrences frequently occur. The aim of this study was to describe different treatment options, surgical complications, and to develop a follow-up regime based on a systematic literature review and meta-analysis of foot and ankle lesions. METHODS AND RESULTS: 1284 studies published between 01/1966 and 06/2021 were identified. 25 met the inclusion criteria, with a total of 382 patients. Of these, 212 patients had a diffuse (dTGCT) and 170 a localized (lTGCT) TGCT. Patients with a dTGCT had a mean age of 36.6±8.2 years, and 55% were female. The overall complication rate was 24% in dTGCT, irrespective of the therapeutic procedure; the mean follow-up was 37.9±27.4 months with a recurrence rate of 21%, and recurrences occurred between 3 and 144 months, the vast majority (86%) within the first 5 years following intervention. Patients with a lTGCT had a mean age of 31.2±5.7 years, and 53% were female. Complications occurred in 12%. The mean follow-up was 51.1±24.6 months, the recurrence rate was 7%, and recurrence occurred between 1 and 244 months after intervention. CONCLUSION: Diffuse TGCTs of the foot and ankle region have a remarkable recurrence rate irrespective of therapeutic procedures, and most lesions reoccurred within 5, with more than half of these in the first 2 years. The lTGCTs are well treatable lesions, with a low recurrence and a moderate complication rate. Based on these findings, we propose a follow-up regime for the dTGCT including a clinical survey and MR imaging 3 months after surgical intervention (baseline), followed by twice-yearly intervals for the first 2 years, yearly intervals up to the fifth year, and further individual follow-up due to the fact that recurrences can even occur for years later. For the lTGCT a clinical survey and MRT is proposed after 3-6 months after intervention (baseline), followed by annual clinical examination for 3 years, and in case of symptoms MR-imaging. Larger prospective multi-center studies are necessary to confirm these results and recommendations.

Rabdomiosarcoma alveolar con metástasis cardíaca en un paciente pediátrico / Alveolar rhabdomyosarcoma with cardiac metastasis in a pediatric patient

El rabdomiosarcoma es el tumor maligno de partes blandas más frecuente en la edad pediátrica. Puede afectar cualquier localización anatómica. El subtipo histológico alveolar suele causar lesiones en las extremidades en niños de mayor edad. Los sitios metástasicos más frecuentes son el pulmón, la médula ósea, el hueso y los ganglios linfáticos. Describimos el caso de un paciente con rabdomiosarcoma alveolar (RA) con metástasis cardíaca, una presentación poco frecuente de la patología.

Rhabdomyosarcoma is the most common malignant soft tissue tumor in pediatric age. It can affect any anatomical location. Alveolar histological subtype usually presents lesions on the extremities in older children. The most common metastatic sites are the lung, bone marrow, bone and lymph node. We describe a case of alveolar rhabdomyosarcoma with cardiac metastasis in a pediatric patient, a rare presentation of the pathology.

Acral Calcified Vascular Leiomyoma: Report of 3 Cases and Literature Review.

ABSTRACT: Angioleiomyomas are benign neoplasms, which usually present as solitary, slow-growing nodules on the skin of lower extremities, but acral location on the hands or feet is unusual. Yet, microscopically, they may show many histopathological variants, focal calcification is uncommon. Extensive calcification masquerading the real nature of the tumor has been rarely reported, the term acral calcified leiomyoma having been proposed for this entity. This change is more often in distal locations and has been interpreted as degenerative in nature, probably related to repetitive minor trauma. We report 3 examples of this unusual condition on the feet of 2 male and one female subjects (aged, 68, 69, and 80 years) and make a review of the 31 cases available in the literature. Two of our cases are associated with highly uncommon features, such as transepidermal calcium elimination and concomitant calcaneal spur.

Microcystic Adnexal Adenoma: The Benign Counterpart of Microcystic Adnexal Carcinoma.

ABSTRACT: Microcystic adnexal carcinoma (MAC) is a low-grade malignant neoplasm of slow growth and low metastatic potential, but locally aggressive. Architecturally, MAC is usually a poorly circumscribed neoplasm that tends to extend deeply into the dermis and subcutaneous tissue. We present here a lesion in which the histopathologic study showed a well-demarcated nodular lesion involving the mid dermis and composed of small cystic keratinous structures, solid aggregates of pale squamous cells without cytologic atypia and ductal structures. Although these neoplastic components resembled those of MAC, the sharp delimitation of the lesion as well as the absence of deep extension and perineural involvement supported the benign nature of this lesion. We have named this neoplasm microcystic adnexal adenoma, as the benign counterpart of MAC.