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Equine clinicians and researchers often make the diagnosis of equine sarcoids (ES) on clinical assessment alone, without histopathological confirmation. However, the accuracy of the clinical diagnosis of ES has not been critically assessed. To assess sensitivity, specificity, positive and negative predictive values of the clinical diagnosis of ES, 40 clinical cases with histologically confirmed equine skin lesions (26 ES and 14 non-ES) were compiled in a representative online examination. For each case and lesion, at least one photograph and all relevant information were presented in a standardised format. This included the horse's signalment, lesion localisation, lesion progression, presence of other skin lesions, earlier treatments and response to treatment. No information relevant for the assessment of the lesion was intentionally withheld. Fourteen ES experts, 39 board-certified equine specialists, 103 equine practitioners and 25 novices categorised the cases into ES or non-ES and graded their level of diagnostic confidence on a scale from 1 to 6 for each case. The overall success rate was 82.0% while sensitivity and specificity were 83.3% and 79.6%, respectively. The positive and negative predictive values were 88.4% and 72.0%, respectively, in the tested population with a 66% prevalence of ES. However, less experienced veterinarians were frequently wrong in their clinical judgement despite a high level of diagnostic confidence. Therefore, the authors propose to develop a diagnostic tool to help clinicians optimise their selection of lesions requiring a biopsy. Ultimately, this will help reduce costs and morbidity generated by unnecessary diagnostic and therapeutic efforts.

Equine sarcoid is the most common skin tumor of horses. Clinically, it occurs as a locally invasive, fibroblastic, wart-like lesion of equine skin, which has 6 clinical classes: occult, verrucose, nodular, fibroblastic, mixed, and malignant. Sarcoids may be single but multiple lesions are more frequent. The typical histological feature is increased density of dermal fibroblasts which form interlacing bundles and whorls within the dermis. Lesions are mostly persistent, resist therapy, and tend to recur following treatment. In general, sarcoids are not fatal but their location, size, and progression to the more aggressive form may lead to the withdrawal of a horse from use and serious infringement of their welfare leading to the loss of valuable animals. Bovine papillomavirus (BPV) type 1 and less commonly type 2 contribute to the development of equine sarcoid. The viral genome and proteins are detected in a high percentage of cases. Furthermore, viral oncoprotein activity leads to changes in the fibroblastic tissue similar to changes seen in other types of tumors. Equine sarcoids are characterized by a loss of tumor suppressor activity and changes allowing abnormal formation of the affected tissue, as well as y immune defense abnormalities that weaken the host’s immune response. This impaired immune response to BPV infection appears to be crucial for the development of lesions that do not spontaneously regress, as occurs in BPV-infected cows.

Interleukin (IL)-2 stimulates antitumour immunity and is successfully used for the treatment of different neoplasias.Canarypox virus locally expressing feline IL-2 is safe and can be used to treat equine sarcoids.Twenty horses of different breeds with a median age of eight years (interquartile range 6.0-13.3 years) and a total number of 59 sarcoids were included in the study.In this prospective clinical trial, sarcoids were injected twice seven days apart, with a recombinant canarypox virus expressing feline IL-2. Complete blood counts (CBC) and fibrinogen levels were measured before treatment and on days 1, 2, 7 and 8.Complete regression was achieved in eight horses (40%) and partial regression in two horses (10%). No change in sarcoid size was observed in two horses (10%) and the disease progressed in five horses (25%). Sarcoids of three horses (15%) showed initial response followed by tumour growth. There were no significant changes in CBC and fibrinogen levels after either injection. One horse developed a mild fever the day after each injection, which subsided without treatment the following day.Treatment of equine sarcoids with recombinant canarypox virus expressing feline IL-2 seems to be a safe therapy option. Although the expression of IL-2 after vector injection and its biological activity in horses were not proven in this study, the treatment resulted in regression and partial regression in 50% of the cases. Further studies are necessary to verify these findings and to establish a treatment protocol.L’interleukine (IL)-2 stimule l’immunité anti-tumorale et est efficacement utilisée pour le traitement de différentes néoplasies. HYPOTHÈSES/OBJECTIFS: Canarypoxvirus exprimant localement IL-2 félin est sûr et peut être utilisé pour traiter les sarcoïdes équins.Vingt chevaux de différentes races avec un âge médian de huit ans (écart interquartille de 6.0-13.3 ans) et un nombre total de 59 sarcoïdes ont été inclus dans l’étude. MÉTHODES: Dans cette étude clinique prospective, les sarcoïdes ont été injectés deux fois à sept jours d’intervalle avec un canarypoxvirus recombinant exprimant IL-2 félin. Une formule sanguine (CBC) et les taux de fibrinogènes ont été mesurés avant traitement et à jours 1, 3, 7 et 8. RÉSULTATS: Une régression complète a été obtenue pour huit chevaux (40%) et une régression partielle pour deux chevaux (10%). Aucun changement de taille des sarcoïdes n’a été observé pour deux chevaux (10%) et la maladie s’est aggravée pour cinq chevaux (25%). Les sarcoïdes de trois chevaux (15%) ont montré une réponse initiale puis une croissance de la tumeur. Il n’y avait pas de changement significatif dans le CBC et les taux de fibrinogènes après chacune des injections. Un cheval a développé une fièvre modérée le jour après chaque injection, qui disparaissait sans traitement le jour suivant.Le traitement des sarcoïdes équins avec canarypoxvirus exprimant IL-2 félin semble être une option thérapeutique sure. Bien que l’expression d’IL-2 après injection du vecteur et son activité biologique chez les chevaux n’aient pas été prouvées dans cette étude, le traitement résultaient en une régression et une régression partielle dans 50% des cas. D’autres études sont nécessaires pour vérifier ces données et pour établir un protocole thérapeutique.INTRODUCCIÓN: la interleuquina 2 (IL-2) estimula la inmunidad antitumoral y se utiliza con éxito para el tratamiento de diferentes neoplasias. HIPÓTESIS/OBJETIVOS: El poxvirus de canarios que expresa localmente IL-2 felina es seguro y puede usarse para tratar sarcoides equinos. ANIMALES: se incluyeron en el estudio veinte caballos de diferentes razas con una mediana de edad de ocho años (rango intercuartílico 6,0-13,3 años) y un total de 59 sarcoides. MÉTODOS: en este ensayo clínico prospectivo, se inyectaron sarcoides dos veces con siete días de diferencia, con un poxvirus de canarios recombinante que expresaba IL-2 felina. Se midieron los recuentos sanguíneos completos (CBC) y los niveles de fibrinógeno antes del tratamiento y en los días 1, 2, 7 y 8. RESULTADOS: se logró una regresión completa en ocho caballos (40%) y una regresión parcial en dos caballos (10%). No se observó ningún cambio en el tamaño del sarcoide en dos caballos (10%) y la enfermedad progresó en cinco caballos (25%). Los sarcoides de tres caballos (15%) mostraron una respuesta inicial seguida de crecimiento tumoral. No hubo cambios significativos en los niveles de CBC y fibrinógeno después de cualquiera de las inyecciones. Un caballo desarrolló una fiebre leve al día siguiente de cada inyección, que remitió sin tratamiento al día siguiente. CONCLUSIONES: El tratamiento de los sarcoides equinos con el poxvirus de canarios recombinante que expresa IL-2 felina parece ser una opción terapéutica segura. Aunque la expresión de IL-2 después de la inyección del vector y su actividad biológica en caballos no se probaron en este estudio, el tratamiento resultó en regresión y regresión parcial en el 50% de los casos. Se necesitan más estudios para verificar estos hallazgos y establecer un protocolo de tratamiento.Interleukin (IL)-2 stimuliert die Antitumor Immunität und wird erfolgreich zur Behandlung verschiedener Neoplasien eingesetzt.Das Kanarienpoxvirus, welches lokal felines IL-2 exprimiert ist sicher und kann verwendet werden, um equine Sarkoide zu behandeln.Es wurden zwanzig Pferde verschiedener Rassen mit einem medianen Alter von acht Jahren (Interquartilsabstand 6,0-13,3 Jahre) und insgesamt 59 Sarkoide in die Studie aufgenommen.Eine völlige Remission wurde bei acht Pferden (40%) erzielt und eine partiale Remission bei zwei Pferden (10%). Es konnte bei zwei Pferden keine Veränderung der Sarkoidgröße beobachtet werden (10%) und bei fünf Pferden verlief die Erkrankung progressiv (25%). Die Sarkoide von drei Pferden (15%) zeigten anfangs eine Verbesserung, gefolgt von vermehrtem Tumorwachstum. Es gab nach der jeweiligen Injektion keine signifikanten Veränderungen bei Blutbild und Fibrinogenwerten. Ein Pferd hatte am Tag nach jeder Injektion ein mildes Fieber, welches ohne Behandlung am darauffolgenden Tag wieder verschwand.Eine Behandlung equiner Sarkoide mit rekombinantem Poxvirus, welches felines IL-2 exprimiert, scheint eine sichere Therapieoption darzustellen. Obwohl die Exprimierung von IL-2 nach einer Vektorinjektion und seine biologische Aktivität bei Pferden in dieser Studie nicht bestätigt werden konnten, resultierte die Behandlung ini 50% der Fälle in einer völligen bzw partialen Regression. Es sind weitere Studien nötig, um diese Befunde zu verifizieren und um ein Behandlungsprotokoll zu erstellen.背景: インターロイキン (IL)-2 は抗腫瘍免疫を刺激し、さまざまな腫瘍の治療に使用されている。 仮説/目的: ネコIL-2を局所的に発現するカナリアポックスウイルスは安全で、馬のサルコイドの治療に使用することができる。 被験動物: 年齢中央値が8歳 (中間値範囲6.0~13.3歳) の異なる品種の馬20頭、合計59のサルコイドを研究に含めた。 方法: 本前向き臨床試験では、サルコイドにネコIL-2を発現する組換えカナリアポックスウイルスを7日間隔で2回注射した。全血球計算(CBC)およびフィブリノーゲン値を治療前、治療後1、2、7、8日目に測定した。 結果: 8頭 (40%) の馬で完全退行が、2頭 (10%) で部分退行を達成した。サルコイドのサイズの変化は2頭 (10%) に認められず、5頭 (25%) で病状が進行した。3頭の馬 (15%) のサルコイドは初期反応を示し、その後腫瘍の増殖が認められた。いずれの注射を行ってもCBCおよびフィブリノゲン値に有意な変化はなかった。1頭の馬は各注射の翌日に軽度の発熱を示したが、翌日には治療せずに治まった。 結論: ネコIL-2を発現する組換えカナリアポックスウイルスを用いた馬のサルコイド治療は、安全な治療オプションの一つであると思われる。本研究では、ベクター注入後のIL-2の発現および馬における生物学的活性は証明されなかったが、治療により50%の症例で退行および部分的な退行が得られた。これらの知見を検証し、治療プロトコールを確立するためには、さらなる研究が必要である。.背景: 白细胞介素(IL)-2刺激抗肿瘤免疫, 并成功用于治疗不同的肿瘤。 假设/目的: 局部表达猫IL-2的金丝雀痘病毒是安全的, 可用于治疗马结节病。 动物: 研究纳入了20匹不同品种的马, 中位年龄为8岁 (四分位距6.0-13.3岁) , 共59种结节病。 方法: 在这项前瞻性临床试验中, 结节病每隔七天注射两次, 用表达猫IL-2的重组金丝雀痘病毒。在治疗前和第1、2、7和8天检测血常规 (CBC)和纤维蛋白原水平。 结果: 8匹马(40%)达到完全缓解,2匹马(10%)达到部分缓解。2匹马(10%)未观察到结节病大小变化, 5匹马(25%)疾病有所发展。3匹马(15%)的结节病显示初始缓解, 随后肿瘤生长。两次注射后,CBC和纤维蛋白原水平均无显著变化。1匹马在每次注射后第二天出现轻度发热, 第二天未经治疗退烧。 结论: 用表达猫IL-2的重组金丝雀痘病毒治疗马结节病,似乎是一种安全的治疗选择。尽管本研究未证实载体注射后IL-2的表达及其在马体内的生物活性, 但该治疗使得50%的病例缓解和部分缓解。有必要进行进一步研究,以验证这些结果并确立治疗方案。.A interleucina (IL)-2 estimula a imunidade antitumoral e é utilizada com sucesso no tratamento de diferentes neoplasias. HIPÓTESE/OBJETIVOS: O vírus canarypox que expressa IL-2 felina localmente é seguro e pode ser usado para tratar sarcóides equinos.Vinte cavalos de raças diferentes com idade mediana de oito anos (intervalo interquartil 6,0-13,3 anos) e um número total de 59 sarcoides foram incluídos no estudo. MÉTODOS: Neste ensaio clínico prospectivo, o vírus canarypox recombinante expressando IL-2 felina foi injetado nos sarcoides duas vezes em um intervalo de sete dias. Hemogramas completos (HM) e níveis de fibrinogênio foram mensurados antes do tratamento e nos dias 1, 2, 7 e 8.Regressão completa foi obtida em oito cavalos (40%) e regressão parcial em dois cavalos (10%). Nenhuma mudança no tamanho do sarcóide foi observada em dois cavalos (10%) e a doença progrediu em cinco cavalos (25%). Os sarcoides de três cavalos (15%) apresentaram boa resposta inicial seguida de crescimento do tumor. Não houve alterações significativas no hemograma e nos níveis de fibrinogênio após qualquer injeção. Um cavalo apresentou febre moderada no dia seguinte de cada injeção, que cedeu sem tratamento em um dia. CONCLUSÕES: O tratamento de sarcóides equinos com vírus canarypox recombinante que expressa IL-2 felina parece ser uma opção de terapia segura. Embora a expressão de IL-2 após a injeção do vetor e sua atividade biológica em equinos não tenham sido comprovadas neste estudo, o tratamento resultou em regressão e regressão parcial em 50% dos casos. Mais estudos são necessários para verificar esses achados e se estabelecer um protocolo de tratamento.

Sarcoids are the most commonly diagnosed skin tumours in equines. Bovine papillomaviruses (BPVs) are the primary causative agent of sarcoids. There has been intensive research to discover the molecular mechanisms that may contribute to the aetiopathogenesis of this disease and tumour suppressors and proto-oncogenes known to play a role in human neoplastic conditions have been investigated in equine sarcoids. Current approaches include the identification of gene expression profiles, characterising sarcoid and normal skin tissues, and an assessment of epigenetic alterations such as microRNA differential expression and DNA methylation status. This review focuses on selected groups of genes that contribute to the molecular mechanisms of sarcoid formation. These genes have the potential to complement current clinical examinations of equine sarcoid disease in diagnosis, prognosis, therapeutic response and screening.

Sarcoids are common equine skin tumors where the risk of recurrence after treatment is high, and better treatment options are warranted. Calcium electroporation is a novel anti-cancer treatment where lethally high calcium concentrations are introduced into the cells by electroporation, a method where short high-voltage pulses induce transient permeabilization of the cell membrane. This study investigated the safety and long-term response of calcium electroporation on sarcoids. Thirty-two sarcoids in eight horses were included. The study suggested that calcium electroporation is a safe and feasible treatment for sarcoids, including inoperable sarcoids. Horses were treated once (2/8) or twice (6/8) under general anesthesia, where sarcoids were injected with 220 mM calcium chloride followed by electroporation with 8 pulses of 100 &mu, s, 1 kV/cm, and 1 Hz. Biopsies were taken prior to treatment. The sarcoid size was monitored for 12&ndash, 38 weeks after the first treatment. Complete response was observed in 22% (6/27) of treated sarcoids, and partial response in 22% (6/27), giving a 44% total response. Treatment efficacy did not appear to be related to location, type, or size. In all non-biopsied lesions, a complete response was seen (4/4). In conclusion, in this small study, 44% of sarcoids responded with 22% of sarcoids disappearing.

Research has shown that the accuracy of the clinical diagnosis of equine sarcoids (ES) can be improved. Particularly, less experienced veterinarians are often mistaken in their clinical judgement despite a high level of diagnostic confidence. The aim of this study was to develop and assess the performance of a diagnostic protocol (DP) to improve diagnostic accuracy and identify diagnostically challenging cases. The design of the DP was based on typical clinical features of ES and its algorithm was optimised through repeated tests on clinical cases prior to validating its performance in a representative online examination. A total of 22 equine practitioners and 31 veterinary students used the DP to diagnose 40 standardised ES and non-ES cases in an online examination. Scores of these 53 respondents were compared to scores of 128 respondents of comparable levels of expertise, and 14 experts, all assessing the same cases without using the DP. Overall, respondents using the DP were significantly more likely (odds ratio (OR) 1.25; 95% confidence interval (95% CI) 1.09-1.43) to diagnose a case correctly compared to respondents not using the DP and felt significantly more confident of their diagnosis (OR 1.53; 95% CI 1.39-1.67). Thus, the DP proved to be a reliable tool to increase clinical diagnostic accuracy and diagnostic confidence. The DP algorithms may be further improved with experiences gained from its application in equine practice and clinicians will be able to optimise their diagnostic accuracy and selection of lesions requiring a biopsy.

The equine sarcoid is a common, locally aggressive fibroblastic cutaneous skin tumour. It can appear anywhere on the body, but is most commonly found on areas where flies can land, such as the medial thigh or neck. There are six distinct forms of equine sarcoid and these range from less severe forms to more aggressive types. There are a number of treatment options, and the treatment will depend on the individual horse. This article describes the six types of equine sarcoids and discusses the treatment options available.

Objective: To assess Equine Sarcoid: Epidemiology and its clinical impact in working donkeys in selected districts of central Ethiopia. Methods: A Cross sectional study was conducted between November, 2009 to April 2010 to assess the epidemiology and clinical impact of equine sarcoids in working donkeys. A structured questionnaire survey was also designed to collect data on current status of sarcoid on donkeys. A random sampling technique was used to select a total of 394 working donkeys in this study. Selected donkeys were clinically examined properly for visible skin lesion. Results: Among a total of donkeys observed during study period, 31 (7.9%) were diagnosed sarcoid positive. A Chi square analysis was used to determine degree of association between risk factors and prevalence of sarcoid infection. The analysis revealed that sarcoid in working donkeys were significantly higher (P

E quine sarcoids are a problematic and frustrating form of skin ‘cancer’ affecting all types of equid. Despite the availability of over 40 different treatment modalities, none provides a 100% cure. Inappropriate treatment is dangerous as it can trigger aggressive local expansion of the sarcoid, severely impacting the use and value of the animal. It is, therefore, imperative that owners seek prompt veterinary advice regarding diagnosis and treatment of sarcoids, and use the most appropriate treatment as the first-line option. Equine sarcoids have been recognised for thousands of years and are currently responsible for approximately 90% of the skin tumours recognised in horses and ponies across the world. They are associated with the presence of bovine papilloma-virus types 1 and 2, although the actual pathophysiology is complex and extremely unpredictable. Sarcoids occur in approximately 3–8% of horses, with often very variable appearances and behaviours. A clinically-based classification is described in Table 1. Each sarcoid type should be considered a form of equine skin cancer — a tumour of the fibroblast cells responsible for many structural aspects of the skin, including wound healing and scar tissue formation.

Different types of sarcoid were recorded in 145 drafting equine animals admitted to Brooke mobile clinic in Delta region, Egypt during the period from 2016 to 2018. All cases were diagnoses based on the case history, clinical picture and histopathological examination. Animals suffered from granulomatous ulcerative lesions in head and neck region (n=63), hind limbs (n=25), fore limbs (n=42) and other sites as chest, trunk and perineal region (n=15). Lesions appeared spontaneously, and its size increased with time. Some of them were round firm pedunculated while others were non-pedunculated (sessile). Some of them had characteristic fleshy ulcerated appearance while others had rough ulcerated surface. The most common types of sarcoid recorded in this study were fibroblastic (n=103), verrucous(n=8), nodular (n=7), mixed (n=20) and occult (n=7).

Photodynamic therapy (PDT) holds great promise in treating veterinary and human dermatological neoplasms, including equine sarcoids, but is currently hindered by the amount of photosensitiser and light that can be delivered to lesions thicker than around 2 mm, and by the intrinsic antioxidant defences of tumour cells. We have developed a new PDT technique that combines an efficient transdermal penetration enhancer solution, for topical delivery of 5-aminolevulinic acid (ALA) photosensitiser, with acute topical post-PDT application of the glycolysis inhibitor lonidamine. We show that the new PDT combination treatment selectively kills sarcoid cells in vitro, with repeated rounds of treatment increasing sarcoid sensitisation to PDT. In vivo, ALA PDT followed by 600 μM lonidamine substantially improves treatment outcomes for occult, verrucous, nodular and fibroblastic sarcoids after 1 month (93% treatment response in 27 sarcoids), compared with PDT using only ALA (14% treatment response in 7 sarcoids).

Compared to other animals, especially companion animals like dogs, neoplasias of the external genitalia are rarely diagnosed in the horse. The most commonly occurring tumors are squmaous cell carcinomas and equine sarcoids; papillomas, melanomas, fibromas, fibrosarcomas or lymphomas are found more infrequently. Squamous cell carcinomas usually afflict older horses, mostly geldings and occasionally stallions, while younger horses tend to have a disposition towards developing equine sarcoids. Special attention should be paid to thorough diagnostics in order to initiate a precise therapy at an early stage, before the tumors are inaccessible due to invasive growth or even metastasis.

Topical acyclovir application is an owner-friendly treatment for occult equine sarcoids, without the caustic side-effects other topical treatments have. Variable clinical success rates have been described, but it is not known to what rate and extent acyclovir penetrates in and through equine skin from a topical formulation. In the current study, an in vitro Franz diffusion model was used to determine the permeation parameters for a generic 5% acyclovir cetomacrogol cream for both healthy and sarcoid equine skin. The distribution of acyclovir between different layers of both skin types was also evaluated. While acyclovir penetrated through both skin types, significantly less acyclovir permeated to the deep dermis of sarcoid skin (197.62ng/mm(3)) compared to normal skin (459.41ng/mm(3)). Within sarcoid skin samples, significantly higher acyclovir concentrations were found in the epidermis (983.59ng/mm(3)) compared to the superficial dermis (450.02ng/mm(3)) and the deep dermis. At each sample point, significantly more acyclovir permeated to the receptor fluid through normal skin compared to sarcoid skin, which is reflected in the significantly higher permeation parameters of normal skin. Normal skin was found to be more permissive for acyclovir, but even in sarcoid skin, enough acyclovir reached the deep dermis to treat a Herpes simplex virus infection. In the case of equine sarcoids, the treatment is aimed at the Bovine papillomavirus and no information is available on the susceptibility of the DNA polymerase of this virus for acyclovir. Therefore, further research is needed to determine the efficacy of acyclovir to treat equine sarcoids.

Imiquimod is an immune response modifier with potent antiviral and antitumour activity. The objective of this pilot study was to evaluate the efficacy of an imiquimod 5% cream (Aldaratrade mark: 3M, Saint Paul, MN, USA) as a topical treatment for equine sarcoids. Fifteen horses with a total of 19 tumours were enrolled, including mixed (7), fibroblastic (5), flat (3), verrucous (2), and nodular (2) types. Baseline data included history, physical examination, tumour location, measurement and digital photography. Imiquimod was applied by the owners three times a week until complete resolution of the tumour or 32 weeks, whichever occurred first. Tumours were measured and photographed every 4 weeks. Treatment efficacy was defined as 75% or greater reduction of tumour size by the end of the trial. Four sarcoids were withdrawn from the study. Twelve of the remaining 15 tumours (80%) showed more than 75% reduction in size and nine (60%) totally resolved between 8 and 32 weeks. The most common adverse effects of exudation, erythema, erosions, depigmentation and alopecia were limited to the tumour and adjacent areas. The results suggest that topical imiquimod is a therapeutic option for the treatment of equine sarcoids, although more detailed studies are required to corroborate these initial findings.

Summary Background Medical textiles offer a unique contact opportunity that could provide value-added comfort, reliability, and safety for light or laser-based applications. We investigated a luminous textile diffuser for use in photodynamic therapy. Methods Textile diffusers are produced by an embroidery process. Plastic optical fibers are bent and sewn into textile to release light by macrobending. A reflective backing is incorporated to improve surface homogeneity, intensity, and safety. Clonogenic assay (MCF-7 cells) and trypan blue exclusion (NuTu19 cells) tests were performed in vitro using 0.1 μg/ml m-THPC with three textile diffusers and a standard front lens diffuser. Heating effects were studied in solution and on human skin. PDT application in vivo was performed with the textile diffuser on equine sarcoids (three animals, 50 mW/cm 2 , 10–20 J) and eight research animals. Lastly, computer simulations were performed to see how the textile diffuser might work on a curved object. Results At low fluency rate, there is a trend for the textile diffuser to have lower survival rates than the front lens diffuser for both cell lines. The textile diffuser was observed to retain more heat over a long period (>1 min). All animals tolerated the treatments well and showed similar initial reactions. The simulations showed a likely focusing effect in a curved geometry. Conclusions The initial feasibility and application using a textile-based optical diffuser has been demonstrated. Possibilities that provide additional practical advantages of the textile diffuser are discussed.

The purpose of the present study was to examine whether bovine papillomavirus (BPV) DNA can be detected on the normal skin and in the habitual surroundings of horses with and without equine sarcoids by means of superficially taken swabs. In affected horses, no significant difference in presence of BPV-DNA could be observed between samples obtained from the equine sarcoid surface, from normal skin close to the tumour and from a normal skin site in direct contact with the tumour. From the group of healthy horses living in contact with affected horses, 44% were BPV-DNA positive. The surroundings of affected and non-affected horses are probably not a major source of BPV-DNA contamination. It can be concluded that BPV-DNA is present on the normal skin of horses affected by equine sarcoid and to a lesser degree, on the normal skin of horses living in contact with affected horses.

Ninety-five horses with sarcoids were subjected to three types of treatment: surgical excision (conventional or carbon dioxide laser), cryotherapy or local BCG vaccination. The type of treatment was selected on the basis of the size, location and clinical appearance of the tumours. The choice between conventional and laser excision was empirical. A successful outcome was obtained in 1 1 of 14 (79 per cent) of the horses treated by cryosurgery, 18 of 27 (67 per cent) treated by BCG vaccination, 18 of 22 (82 per cent) treated by conventional excision, and 20 of 28 (71 per cent) treated with a carbon dioxide laser. For both excision methods, rigorous measures were taken to avoid autoinoculation and to ensure a wide margin of normal skin. The probability of local recurrence after excision was significantly higher for large sarcoids and sarcoids which had previously failed to respond to treatment. In 10 of the 31 horses with remaining sarcoids, some or all of the untreated sarcoids were observed to regress spontaneously.

Logistic regression analysis was applied to data from a population of donkeys to obtain statistical models estimating the risk of equine sarcoid. Two models were constructed and compared. The group model was derived using the prevalence of animals with sarcoids in groups, classified according to the explanatory variables gender, age at first exposure (considered as age at entry to the population), duration of exposure, and gender by duration of exposure as an interaction. The subject model was derived from individual animal data and consisted of the factor gender with the covariates age at first exposure and duration of exposure. Age at first exposure was represented in the model by linear and quadratic terms, and as an interaction with duration of exposure. Both models provided a good approximation to the observed data. The analyses identified young male donkeys with short duration of exposure as being at highest risk. We concluded that risk assessment using the group model could be used effectively in the clinical management of sarcoids in the population of donkeys. Frequent examination of high risk groups might allow early diagnosis, therapeutic intervention and improved animal welfare.

Whereas in human medicine photodynamic therapy represents a well-known and recognized treatment option for diverse indications, it is still little known and unfortunately not yet established treatment option for pets. Various photosensitizers and light sources have been used and clinical results have been published. The main indication is a frequently occurring skin tumor in cats: in situ carcinoma/squamous cell carcinoma, mainly found in not or only slightly pigmented areas of the head. For early stages of this tumor, promising results have been published, partly using new, selective drugs to decrease light sensitivity after systemic administration and to increase response rates. Other possible indications are urinary tract neoplasia of dogs and equine sarcoids, the latter representing very common tumors in horses where no effective treatment is known so far. This review article summarizes the role of photodynamic therapy in veterinary medicine.

Associations between clinical parameters of sarcoids and the equine leucocyte antigen system (ELA) were analysed for 120 Swedish horses. Median age of affected horses was 5.2 years, and the majority presented with solitary tumors between 2 and 5 cm in diameter and ventral abdomen was a predilection site. Clinical signs first appeared at a median age of 3.5 years, and sarcoids at different locations first appeared at different ages. Lesions at different sites differed in size, and multiple tumors, early onset, long duration, and older age all had an association with large size. Clinical manifestations of sarcoids and the association between certain ELA-specificities and early onset (A5) and increased recurrence rates after surgery (W13), in addition to increased prevalence (A3W13), strengthen further that some horses are inherently predisposed to sarcoid growth. Unassociated with any clinical parameters, one third of the untreated horses became free of sarcoids due to "spontaneous" regression, perhaps as a result of immune responses against the tumors. Seventy percent of the horses were treated (mostly by excision), and large size was the main parameter promoting treatment. Excision had no significant effect on possibly remaining sarcoids. Recurrence rate after first treatment was about 35%, with the majority of tumors recurring within 4 months. Early onset, long duration, large size, and localization to distal limbs all appeared to increase risk of recurrence. Early treatment, performed under general anesthesia in recumbency which permits wide excision and measures to avoid autoinoculation, significantly reduced recurrence rates.

THE term ‘sarcoid’ is derived from the apparent sarcomatous appearance of the lesions as well as their tendency to recur following excision. The numbers of sarcoid (previously called 9warts9) on any individual case, their character, distribution and extent, have a major bearing on the selection of the available treatment options. Clearly, the frustrations felt by many generations of veterinary surgeons have continued up to the present time; the equine sarcoid is probably the most common cutaneous reason for euthanasia and the loss to the equine industry is considerable. Horses in which there are few localised superficial lesions are usually amenable to any of the treatment options, although inadequate application will yield a poor result with a high rate of recurrence at the site and possible extension to other sites. No effective means of treating the malevolent type of sarcoid has yet been found and interfering with this particularly aggressive form merely exacerbates the signs.

Equine sarcoids are the most common tumor of horses. Bovine papillomavirus (BPV) has been suggested as the cause of sarcoids. Studies have shown that BPV is present in swabs or biopsies from nonsarcoid-bearing equine skin. Skin biopsies from a variety of different conditions and normal skin from horses with no reported history of sarcoids were examined by polymerase chain reaction (PCR) for the presence of BPV, which was found in all different types of skin conditions as well as normal skin. Forty-one out of 86 skin biopsies from horses without sarcoids were found to contain BPV DNA. Laser microdissection, followed by DNA amplification through both PCR and isothermal loop-mediated amplification, was performed on these 41 biopsies and on 70 additional BPV-positive sarcoid biopsies to localize the virus. Location of BPV DNA was different between sarcoid and nonsarcoid groups. Nonsarcoid skin biopsies were more likely to have BPV within intact or inflamed epidermis than sarcoids ( P = 0.016 and P = 0.007, respectively). Areas of inflammation within the dermis and epidermis were more likely to contain BPV than in noninflamed areas ( P = 0.008 and P = 0.009, respectively). Bovine papillomavirus was also found in the epidermis of all types of sarcoids examined, more frequently in occult sarcoids than in fibroblastic and nodular types ( P = 0.03 and P = 0.01, respectively). Results suggest that BPV is commonly found in normal and inflamed equine skin, and it is likely an important predisposing factor in the development of sarcoids.

Treatment options for equine sarcoids are briefly reviewed and the results of a retrospective study of 63 cases of equine sarcoid (66 lesions) treated by clinicians from the Rural Veterinary Centre, Camden, Australia from 1975 to 1993 presented. Five different treatments were employed in the management of these 66 lesions, including surgical excision alone or in combination with cryotherapy, radiotherapy, immunotherapy and tumour transfer to a subcutaneous site on the neck. The majority of cases were treated with surgical excision alone (18/66), excision followed by cryotherapy (31/66) and immunotherapy (16/66), with success rates of 28%, 42% and 81% respectively. Success was defined as no sign of recurrence of the lesion at the time of follow-up, at least 6 months later.

Based on the anecdotally reported eradication of a sarcoid using aciclovir cream, the curative potential of this ointment was investigated in 22 sarcoid-affected horses referred to the Equine Clinic Tillysburg, Austria, between 2006 and 2009. Sarcoid disease was diagnosed by clinical examination and bovine papillomavirus types 1 and 2 from intact skin and tumour tissue. As nine horses had more than one lesion, a total of 47 sarcoids were treated by daily topical application of aciclovir 5 per cent cream for a period of two to six months; in four horses, surgical tumour ablation was performed before treatment. Disease parameters, including the tumour type, number, location and size, were recorded before and after aciclovir therapy. All 47 (100 per cent) of the sarcoids responded to treatment, with complete tumour regression observed for 32 (68 per cent) lesions and no recurrences reported thus far. Incomplete resolution was observed for 15 (32 per cent) lesions, probably due to their thickness. Aciclovir is proposed to be routinely used for the treatment of mild-type sarcoids and as an adjuvant therapeutic agent in combination with surgery.

Objective To document the efficacy of intratumoural injections of 5-fluorouracil for the treatment of equine sarcoids. Design A prospective study that included 13 horses and one donkey. Procedure Sarcoids were confirmed by histological examination and treated with intratumoural 5-fluorouracil every 2 weeks. If the sarcoids did not resolve after seven treatments, treatment was considered a failure. All cases were re-examined 6 months after treatment commenced and owners were telephoned 3 years after commencement of treatment to report on tumour recurrence. Outcome comparisons were performed to determine the effect of previous treatment, tumour size and tumour location on sarcoid resolution. The efficacy of intratumoural 5-fluorouracil was compared with other previously documented treatments of equine sarcoids. Results Sarcoids smaller than 13.5 cm3 were significantly (P = 0.032) more likely to resolve with treatment than larger sarcoids. Sarcoids that were not responsive to previous therapies were significantly (P = 0.007) more likely to recur after 3 years than sarcoids that had not been treated prior to this study. In this study, there were similar rates of resolution in cases with mutiple tumours (66.6%) when compared to cases with single tumours (60%). The numbers in this study were too small to properly evaluate the effect of tumour location on the success of treatment. Intratumoural 5-fluorouracil appeared to have resolved sarcoids in 9 of 13 cases (61.5%) as determined by follow up conversation with the owners 3 years after the initial treatment. Conclusion The use of intratumoural 5-fluorouracil compares favourably with other treatment modalities for sarcoids, with a long term successful resolution rate of 61.5%. Owners should be warned that resistant sarcoids and sarcoids larger than 13.5 cm3 have a poorer prognosis for resolution and more aggressive therapeutic options should be considered.

CO2 lasers has been used for five years at Malaren Equine Hospital, as an alternative treatment of some equine diseases. The application of CO2 laser has been studied for evaluation of its appropriateness for treatment of the equine diseases sarcoids, lameness in fetlock joints or pulmonary haemorrhage. During the last five years, above 100 equine sarcoids have been removed by laser surgery (CO2 laser) and so far resulting in significantly few recurrences compared with results from usual excision surgery. In one study, acute traumatic arthritis in fetlock joints was treated three times every second day with defocalised CO2 laser. The therapeutic effectiveness of CO2 laser in this study was better than that of the customary therapy with betamethasone plus hyaluronan. During one year, chronic pulmonary bleeders, namely exercise induced pulmonary haemorrhage, has been treated with defocalised CO2 laser. Six race horses have been treated once daily during five days. Until now, three of these horses have subsequently been successfully racing and no symptoms of pulmonary haemorrhage have been observed. These studies indicate that CO2 laser might be an appropriate therapy on sarcoids and traumatic arthritis, and probably also on exercise induced pulmonary haemorrhage. Other treatments for this pulmonary disease are few.

Objective— To examine apparently normal skin around equine sarcoids for evidence of bovine papilloma virus (BPV) DNA, and to relate this finding to the observed recurrence after surgery. Study Design— Prospective study. Animals or Sample Population— Forty-one equine sarcoids from 19 horses. Materials and Methods— The tumors were surgically excised at a measured distance of 8, 12, or 16 mm. Samples from the tumor and of the entire surrounding skin were taken at 4, 8, 12, and 16 mm from the tumor border and analyzed for the presence of BPV DNA using polymerase chain reaction (PCR) amplification. The samples were grouped per examined sarcoid, and a tumor was considered positive at a certain distance as soon as at least one of the samples at that distance was positive. The clinical outcome was recorded for each sarcoid after a minimal follow-up of 6 months. Results— All sarcoids were positive for BPV1 or BPV2. The tumor margin was positive at 4, 8, 12, and 16 mm in, respectively, 95%, 73%, 39%, and 33% of the examined sarcoids. Local recurrence was observed in 3 sarcoids on 3 different horses. From survival analysis, there was a greater likelihood for local recurrence when sarcoids had a surgical margin that was positive for BPV DNA. Conclusions and Clinical Relevance— BPV DNA is often detected in visibly normal skin around sarcoids, and there is a significantly greater probability for local recurrence when the surgical margins are positive for the presence of BPV DNA.

Aims To evaluate laser surgery as a sole treatment for sarcoid resection; and determine risk factors for recurrence. Methods Horses included had diode laser surgery to remove ≥1 sarcoid. No previous/concurrent veterinary treatment was administered. Diagnosis was confirmed by histology in all cases. Clinical data were retrieved from the hospital database. Follow-up information was obtained by telephone questionnaire. Results Follow-up data are currently available for 290 sarcoids, in 73 horses, over 177 horse-years. Overall recurrence rate was 1.31 sarcoids per 10 horse-years (95% CI 0.80–2.02). For horses with 1–5 sarcoids, recurrence rate was 0.95 sarcoids per 10 horse-years (95% CI 0.52–1.62). For each additional sarcoid removed, that horse was 1.24 (odds ratio) as likely to have at least one sarcoid recur (95% CI 1.03–1.50; P 0.05). Horses with mixed-type sarcoids were more likely to have recurrence than horses with sarcoids of other types (P = 0.007). Time-to-recurrence (mean 7.6 months, 99% CI 3.2–11.9) was significantly shorter than follow-up time for horses without recurrence (mean 30.0 months, 99% CI 19.8–32.1; P

UMMARY The literature is reviewed concerning the clinical features of equine sarcoids and mention is made of the traditional methods of treating this common skin tumour. The data from 50 horses with sarcoids are reported together with the results of their treatment by cryosurgery. Thirty-four of the animals had earlier been unsuccessfully treated by one or more of the traditional methods, usually excision. The objectives of cryosurgery are defined and some equipment is described; the use of temperature monitors is regarded as imperative for safe and effective treatment. In this study a liquid nitrogen spray apparatus was found to be the single most useful instrument. The horses in this study were often affected by multiple lesions so that not less than 480 sarcoids were subjected to ultrafreezing. Nonetheless 33 horses were cleared of neoplasia and the majority of the remainder were rendered suitable for work. The author emphasises that a cautious prognosis must always be given for horses with sarcoids, and that the greater the number of lesions, the poorer are the prospects of a complete cure. Cryosurgery is reported to be a safe and practicable technique with few complications. Healing is not as rapid as first intention repair of surgical wounds but the absence of cicatrisation makes cryosurgery particularly suitable for tumours of the eyelids. A possible beneficial cryo-immune response is mentioned. It is concluded that cryosurgery should be regarded as one of the treatments of choice for equine sarcoids and that the best results will be obtained from early treatment. RESUME On passe en revue les signes cliniques de l'affection et les methodes traditionnelles du traitement de ces tumeurs cutanees. Puis on rapporte les cas de cinquante chevaux atteints par cette affection et traites par cryochirurgie. Trente six de ces animaux avaient ete anterieurement l'objet d'un traitement chirurgical par excision et sans succes. Les objectifs de la cryochirurgie sont indiques et l'equipement decrit. L'emploi de controles de temperature est regarde comme indispensable. Dans cette etude l'utilisation d'un appareillage utilisant l'azote liquide est apparu comme particulierement efficace. Les chevaux objets de cette etude presentaient souvent des lesions multiples si bien que 480 tumeurs differentes ont ete traitees. Trente trois chevaux furent totalement gueris et la majorite des autres purent reprendre une activite utile. L'auteur indique combien il convient de formuler un pronostic reserve et comment ce pronostic est d'autant plus sombre que le nombre de tumeurs est important sur un meme individu. La cryochirurgie est presentee comme une methode sure et pratique entrainant peu de complications. La cicatrisation n'a point la promptitude d'une premiere intention chirurgicale. La methode est indiquee specialement pour les tumeurs de paupieres. L'existence d'un eventuel processus de cryo immunite est envisage. On conclue en precisant que la cryochirurgie est la methode de choix pour le traitement des sarcoides avec des resultats d'autant meilleurs que l'intervention est precoce. ZUSAMMENFASSUNG Die Literatur uber die klinischen Zuge des Sarcoids wird besprochen und die traditionellen Behandlungs-methoden dieses Hauttumors werden erwahnt. Die Ergebnisse von 50 Sarcoid-Fallen werden zusammen mit den Resultaten der Cryochirurgie wiedergegeben. 34 Tiere waren vorher erfolglos mit einer oder mehreren der traditionellen Methoden (meistens Excision) behandelt worden. Die Zielsetzung der Cryochirurgie wird definiert und die Ausrustung beschrieben; der Gebrauch von Temperaturuberwachungsgeraten wird als Voraussetzung fur eine gefahrlose und wirksame Behandlung angesehen. In dieser Untersuchung erwies sich ein Spraygerat fur flussigen Stickstoff als nutzlichstes Instrument der Ausstaffung. Die behandelten Pferde litten oft an multiplen Sarcoiden, so dass 480 Tumoren mit der Tiefgefriertechnik behandelt werden konnten. 33 Pferde konnten als geheilt beurteilt werden und die Mehrzahl der restlichen Tiere wurden wieder arbeitsfahig. Der Autor streicht heraus, dass immer eine vorsichtige Prognose gestellt werden sollte, je zahlreicher die Tumoren, desto ungustiger werden die Aussichten auf vollstandige Heilung. Die Cryochirurgie wird als sichere und gut praktizierbare Technik mit seltenen Komplikationen beschrieben. Die Heilung verlauft nicht so schnell wie die Primarheilung einer Operationswunde, aber das Fehlen einer Narbe lasst die Cryochirurgie als besonders geeignet fur Augenlidtumoren erscheinen. Es wird geschlossen, dass die Cryochirurgie als eine der Methoden der Wahl fur das equine Sarcoid betrachtet werden sollte und dass die besten Resultate bei fruhzeitiger Behandlung zu erwarten sind.

Three horses with equine sarcoids were treated with radical surgical excision and immediate split-thickness skin grafts. Graft take ranged from 50 to 100%, and the epithelial coverage attained resulted in an early functional repair. In no instance was there a recurrence of the sarcoid.

Clinical observations on the use of BCG cell wall fraction in oil for treating seven horses with periocular sarcoids and five horses with sarcoids in other regions are described. Therapy was successful when used for periocular or solitary and smaller sarcoids. For sarcoids previously treated with cryosurgery, therapy appeared to be less efficient. A horse with a sarcoid on the stifle developed a septic gonitis due to necrosis of the sarcoid tissue adjacent to the joint. Sarcoids of the axilla appeared to be more aggressive than sarcoids at other locations and did not respond favourably to this form of therapy.

JACKSON1 first recognized and described equine sarcoids, which are locally aggressive, fibroblastic tumours of equine skin. They are often multiple, frequently recur following surgical excision or radiotherapy, and generally have fibropapillomatous features. Horses, donkeys and mules are susceptible. Neither a seasonal incidence nor an age distribution of equine sarcoids has been detected2. Jackson pointed out that the gross and microscopic appearance of the tumours, the predilection sites, and the pattern of spread to secondary sites on affected animals were suggestive of viral aetiology. Auto- and homo-transplantation have been reported3–6. Voss recently reported that several tumours were produced in horses with centrifuged sarcoid extracts which probably were cell-free although they had not been filtered5. Intrader-mal inoculation of bovine papilloma virus in horses produced localized, fibroblastic growths similar to equine sarcoid which suggests the interesting possibility of a causal relationship to equine sarcoid7. Equine sarcoid has no known relationship to Boeck's sarcoid in man.