Canine Apocrine Gland Anal Sac Adenocarcinoma: A Review.

Apocrine gland anal sac adenocarcinoma (AGASAC) is a relatively uncommon tumor in the dog and comprises approximately 17% of perianal malignancies; however, it is one of the most common causes of paraneoplastic hypercalcemia. Clinical signs in affected dogs most commonly are associated with mechanical obstruction caused by the primary tumor or enlarged regional metastatic lymph nodes and the effects of paraneoplastic hypercalcemia when present. Surgical excision of the primary tumor and metastasectomy of affected locoregional lymph nodes is the preferred initial treatment option for most dogs, although radiation therapy and adjuvant chemotherapy are commonly incorporated into multi-modality treatment plans. A significant role for the use of adjuvant chemotherapy has not been clearly demonstrated. Prolonged survival times are possible, especially for dogs with smaller primary tumors and for dogs that undergo further treatments for recurrent disease. In this article, we review the clinical signs, diagnosis, staging, treatment, and prognosis of AGASAC in the dog.

Evaluation of electrochemotherapy in the management of apocrine gland anal sac adenocarcinomas in dogs: A retrospective study.

Background: Electrochemotherapy (ECT) combines the administration of anticancer drugs with the delivery of electric pulses, thus increasing the drug uptake through the cell membranes, resulting in increased efficacy. Aim: The aim of our study was to describe the tolerability and efficacy of ECT alone or in association with other treatment modalities for the management of apocrine gland anal sac adenocarcinoma (AGASAC). Methods: Medical records of dogs with a diagnosis of AGASAC that were treated with ECT alone or in combination with surgery/chemotherapy were retrospectively evaluated. Each dog received 20 mg/m2 of bleomycin intravenously. Based on the clinician's decision, the primary tumor or tumor bed was also infiltrated with cisplatin at the dose of 0.5 mg/cm2. Trains of permeabilizing biphasic electric pulses were then applied under general anesthesia. Results: Ten dogs were enrolled in the study. Of those 10 dogs, only one received ECT for treatment of microscopic local disease, while in six cases ECT was the only treatment modality. In three dogs, ECT was followed by systemic medical treatment. Six dogs (60%) had a partial response (PR), three dogs (30%) had stable disease, and one dog treated for microscopic disease did not show any sign of local relapse for 305 days after treatment, being still alive and in complete remission at the time of writing this article. The median time to progression was 303 days and the median survival time was 365 days. The treatment was well tolerated and local side effects were minimal. No systemic effects were documented. Conclusion: This preliminary study suggests that ECT may be beneficial for dogs with AGASAC and could be a useful addition to the current therapeutic options in consideration of its low cost, limited toxicity, and ease of administration.

Enfermedad de Paget extramamaria / Extramammary Paget Disease

ANTECEDENTES Y OBJETIVOS: Existen pocos estudios sobre la enfermedad de Paget extramamaria (EPEM) en la población mediterránea. Nuestro objetivo fue revisar las características de nuestros pacientes con EPEM, su asociación con neoplasia en continuidad y su evolución a largo plazo. PACIENTES Y MÉTODOS: Realizamos un estudio observacional retrospectivo sobre 27 pacientes diagnosticados de EPEM entre 1990-2015. Las historias clínicas fueron revisadas retrospectivamente para obtener los datos clínico-patológicos y de seguimiento. RESULTADOS: Se trata de 20 mujeres y 7 varones de entre 42 y 88 años de edad (mediana de 76 años). Las lesiones se localizaron en la vulva (16 casos), en el pubis-región inguinal (5), en la región perianal (4) y en la axila (2). El tiempo de evolución al diagnóstico osciló entre 1 y 60 meses (mediana de 12 meses) y el diámetro máximo entre 20 y 140 mm (mediana de 55 mm). En 3 casos (11,1%) la EPEM fue secundaria. Ningún caso se desarrolló sobre adenocarcinoma anexial cutáneo previo. Diez de 24 EPEM primarias (41,7%) presentaban invasión de la dermis. Ocho de los 27 pacientes (29,6%) presentaron recidiva local tras el tratamiento quirúrgico inicial. Tres pacientes (11,1%) fallecieron a consecuencia de metástasis de la EPEM. CONCLUSIONES: La presencia de un adenocarcinoma anexial cutáneo subyacente es poco frecuente pero no es rara la existencia de un adenocarcinoma extracutáneo en continuidad. A pesar de que la EPEM suele evolucionar lentamente, es frecuente la invasión de la dermis y no son excepcionales las metástasis. Las recidivas locales son frecuentes a pesar de la extirpación con márgenes amplios y pueden ser tardías, por lo que es preciso un seguimiento a largo plazo

BACKGROUND AND OBJECTIVE: Extramammary Paget disease (EMPD) has seldom been studied in Mediterranean populations. We aimed to review the characteristics of our patients with EMPD, the presence of a neoplasm in continuity, and the long-term course of the disease. PATIENTS AND METHODS: Retrospective observational study of 27 patients diagnosed with EMPD between 1990 and 2015. All clinical and pathology findings related to clinical course and outcomes were retrieved for analysis. RESULTS: Twenty patients were women and 7 were men. Ages ranged from 42 to 88 years (median, 76 years). Lesions were in the following locations: vulva (16 cases), pubis-groin (5), perianal region (4), and axilla (2). Time from onset to diagnosis ranged from 1 to 60 months (median, 12 months) and maximum lesion diameter from 20 to 140 mm (median, 55 mm). In 3 cases (11.1%) EMPD was a secondary condition. None of the lesions developed on a previous cutaneous adnexal adenocarcinoma. Ten of the 24 primary EMPDs (41.7%) invaded the dermis. Eight of the 27 patients (29.6%) experienced local recurrence after the initial surgical treatment.Three patients (11.1%) died as a consequence of metastasis from the EMPD. CONCLUSIONS: The presence of an underlying cutaneous adnexal adenocarcinoma is uncommon, but it is not unusual to find an extracutaneous adenocarcinoma in continuity. Although EMPD is a slow-growing tumor, dermal invasion is frequent and metastasis is not uncommon. Local recurrence is common even after excision with wide margins and may be delated, so long term follow-up is essential

Adherence to follow-up recommendations for dogs with apocrine gland anal sac adenocarcinoma: A multicentre retrospective study.

Progressive disease is common following anal sacculectomy for apocrine gland anal sac adenocarcinoma (AGASACA); additional therapy may prolong survival. Adherence to medical recommendations influences therapeutic success in humans. The purpose of this study was to assess the adherence to follow-up recommendations in dogs with AGASACA. Medical records of patients that underwent anal sacculectomy for AGASACA, with or without iliosacral lymphadenectomy, between July 2015 and July 2018, were reviewed at eight referral institutions to assess post-operative recommendations and owner adherence to recommendations. One hundred and seventy-four dogs were included, of which 162 underwent unilateral anal sacculectomy, 12 underwent bilateral anal sacculectomy and 39 underwent concurrent iliosacral lymphadenectomy. Seventy-six owners (44%) received recommendations for staging at the time of discharge, histopathology results or at the first follow-up visit. One hundred and forty owners (80%) received recommendations for treatment following the initial surgery. Fifty of seventy-six (66%) owners pursued at least one staging recommendation and 69 of 140 (49%) owners pursued some kind of adjuvant treatment recommendation. Overall, 16 of 76 (21%) were adherent to staging recommendations with 20 adherent for the first year following surgery (26%). Forty-seven of 140 (34%) were adherent to treatment recommendations with 54 (39%) adherent for the first year. Owners that were adherent to restaging recommendations at 1 year following surgery were significantly more likely to pursue treatment for progressive disease (P = .014). Further work is required to assess owner motivation and evaluate strategies to improve adherence, given the potential impact on patient treatment.

Malignant anal sac melanoma in dogs: eleven cases (2000 to 2015).

OBJECTIVES: To report the signalment, clinical presentation, treatments pursued and outcomes of dogs with malignant anal sac melanoma. METHODS: Medical records from five institutions from January 2000 through December 2015 were reviewed and dogs with cytologically- or histologically-confirmed malignant anal sac melanoma were identified. Signalment, clinical signs, staging, cytology, histopathologic analysis, surgical and non-surgical treatments were extracted from the medical records. The referring veterinarians and owners were contacted for follow-up data. RESULTS: Eleven dogs were included and survival data was available for all. The most common clinical signs were bloody anal sac discharge and perianal licking. Initial treatments pursued included surgery (n=8), chemotherapy (n=1), and palliative treatment with pain medications and stool softeners (n=2). In an adjuvant setting, melanoma vaccine was pursued following surgery in three dogs and chemotherapy in one dog. Regardless of treatment, progression-free survival (mean 92 · 5 days) and overall survival times (median 107 days) were short. CLINICAL SIGNIFICANCE: Dogs in this case series had a guarded to poor prognosis regardless of treatment. Ten of 11 dogs were euthanased due to local or distant disease progression. Only 1 of 11 dogs was alive one year after diagnosis. An understanding of tumour behaviour in this location could lead to improved survival times with earlier diagnosis and treatment.

Perianal neuroendocrine tumor with suspected lymph node metastasis causing colonic compression and subsequent megacolon.

An 8-year-old spayed female domestic shorthair cat was presented with a 4- to 5-month history of a progressively growing mass above her anus and an inability to defecate for 3 to 4 wk. External perianal and internal regional masses were subsequently identified and diagnosed as tumors of neuroendocrine origin through surgical excision and histopathologic evaluation. The cat was treated with 2 courses of chemotherapy and radiation therapy.

Tumeur neuroendocrinienne périanale avec une métastase suspectée des ganglions lymphatiques causant une compression du côlon et un mégacôlon subséquent. Une chatte commune domestique stérilisée âgée de 8 ans a été présentée avec une anamnèse de 4 ou 5 mois d'une masse à croissance progressive au-dessus de l'anus et l'incapacité de déféquer depuis 3 ou 4 semaines. Les masses périanales externes et régionales internes ont été subséquemment identifiées et diagnostiquées comme des tumeurs d'origine neuro-endocrinienne suite à l'excision chirurgicale et une évaluation histopathologique. La chatte a été traitée à l'aide de deux séries de traitement et d'une radiothérapie.(Traduit par Isabelle Vallières).

Effective treatment of perianal tumors in dogs with electrochemotherapy.

BACKGROUND: Electrochemotherapy is an antitumor therapy that utilizes locally-delivered, short intense direct current electric pulse to the tumor nodule plus chemotherapy. The aim of the present study was to evaluate the electrochemotherapy treatment of perianal tumors of different sizes in dogs. MATERIALS AND METHODS: In 12 dogs, 26 tumor nodules of perianal tumors of different size, and clinically expected to be of different histological type, were treated with electrochemotherapy. Electrochemotherapy consisted of intratumoral injection of cisplatin (1 mg/cm3) or bleomycin (3 mg/cm3), followed by application of electric pulses (8 electric pulses; amplitude, 910 V, duration, 100 micros, frequency, 1 Hz) to the tumor nodule. RESULTS: Responses to treatment were assessed 4 weeks after the therapy; 82% of all tumors treated with electrochemotherapy responded with objective response (OR) (complete response (CR)=41%, partial response (PR)=41%), 16% responded with no change (NC) and 1 tumor (2%) went to progressive disease (PD). At the end of the observation period for each tumor, ranging from 1 to 34 months, 92% OR (CR=65%, PR=27%), 8% NC and no PD were obtained. No major local or general side-effects were noted. CONCLUSION: Electrochemotherapy with cisplatin or bleomycin is an effective treatment of perianal tumors in dogs. The advantages of this therapy are its simplicity, short duration of treatment sessions, low chemotherapeutic doses and insignificant side-effects, as well as the fact that the subject does not have to stay in hospital.

Carcinoma of the apocrine glands of the anal sac in dogs: 113 cases (1985-1995).

OBJECTIVE: To characterize the signalment, clinical signs, biological behavior, and response to treatment of carcinoma of the apocrine glands of the anal sac in dogs. DESIGN: Retrospective study. ANIMALS: 113 dogs with histologically confirmed carcinoma of the apocrine glands of the anal sac. PROCEDURE: Data on signalment, clinical signs, and staging were reviewed and analyzed along with treatment modality for potential association with survival time. RESULTS: Sex distribution was approximately equal (54% female, 46% male). One hundred four dogs underwent treatment consisting of surgery, radiation therapy, chemotherapy, or multimodal treatment. Median survival for treated dogs was 544 days (range, 0 to 1,873 days). Dogs treated with chemotherapy alone had significantly shorter survival (median, 212 days) than those receiving other treatments (median, 584 days). Dogs not treated with surgery had significantly shorter survival (median, 402 days) than those that underwent surgery as part of their treatment (median, 548 days). Dogs with tumors > or = 10 cm2 had significantly shorter survival (median, 292 days) than dogs with tumors < 10 cm2 (median, 584 days). Hypercalcemia was identified in 27% (n = 29) of dogs, and those dogs had significantly shorter survival (median, 256 days), compared with those that were normocalcemic (median, 584 days). Dogs with pulmonary metastasis had significantly shorter survival (median, 219 days) than dogs without evidence of pulmonary metastasis (median, 548 days). CONCLUSIONS AND CLINICAL RELEVANCE: Unlike most previous reports, this study revealed an approximately equal sex distribution, and results suggest a more favorable prognosis.

Perianal mucinous adenocarcinoma.

BACKGROUND: Perianal mucinous adenocarcinoma is a rare variant of anal canal epithelioid tumors. Our objective in this report is to examine the clinical features, pathology, treatment, and outcome for patients with perianal mucinous adenocarcinoma. METHODS: A retrospective review identified four patients with histologically proven perianal mucinous adenocarcinoma. The medical records of these patients were reviewed for presentation, therapy, and outcome. RESULTS: Pain and bleeding were present in all cases. In three of four patients, chronic perirectal disease was present, including two abscesses and one fistula. All patients had extensive local disease at presentation. One patient presented with bilateral inguinal nodal metastases. Two patients received neoadjuvant chemotherapy and radiation, with a third patient receiving radiation alone. Two of these three patients underwent abdominoperineal resection. Three patients subsequently died (all of progression and/or recurrence) 2-48 months after diagnosis. The fourth patient (who was treated with chemotherapy and radiation followed by abdominoperineal resection) is alive and disease free at 12 months. CONCLUSIONS: Perianal mucinous adenocarcinoma is a rare disease with a poor prognosis, mostly due to its advanced nature at the time of diagnosis. Chemoradiation followed by surgery may improve outcome in selected individuals.

Chemoradiation therapy for anal cancer: radiation plus continuous infusion of 5-fluorouracil with or without cisplatin.

Chemoradiation therapy for anal cancer was carried out in 58 patients using low-dose, continuous infusion of 5-fluorouracil (5-FU) with or without continuous infusion of cisplatin (cDDP) and external beam irradiation (chemoXRT). Thirty-nine patients received 5-FU chemoXRT resulting in a local control rate of 50% in those receiving a total dose of < 45 Gy, 73% for those receiving 50-54 Gy, and 83% for those receiving > 60 Gy. The actuarial local control rate at 2 years was 77% after chemoXRT alone; overall local control was 67% at 5 years. In 18 patients receiving 5-FU plus cisplatin with radiation doses of 54-55 Gy, actuarial local control was 85% at 2 years. Fifteen patients failed chemoXRT, 13 of whom had abdominoperineal resection for salvage; the overall local control rate was 93% (54/58). The actuarial survival at 5 years was 81% for the 5-FU chemoXRT group and 94% at 2 years for the 5-FU plus cisplatin chemoXRT group; median follow-up was 54 and 20 months, respectively. Diarrhea and nausea were the most frequent early reactions and were ameliorated by limiting the duration of chemotherapy to 5 days/week and by using XRT techniques to exclude the small bowel from the radiation portal. Serious late radiation complications have not been observed and may be related to XRT fractionation and the use of protracted chemotherapy infusion. The absence of late morbidity coupled with the high local control rate by the use of this chemoXRT program is an area to investigate for improving the therapeutic ratio for the treatment of anal cancers.

Hyperthermic treatment of superficial tumors in cats and dogs.

Local current field radiofrequency hyperthermia was applied to 33 superficial tumors in 11 cats and 5 dogs. Squamous cell carcinoma (SCC) in the cat was the most frequent tumor treated. Of 19 SCC in cats, 13 (68%) were reduced completely, combining complete and partial tumor reduction, there was an 89% favorable response to hyperthermia for SCC. A small number of other tumors such as fibrosarcoma in the cat and perianal tumors in the dog were favorably responsive. Local current field hyperthermia (50 C for 30 sec) resulted in destruction of tumor tissue as well as normal tissue. However, tissue destruction did not extend more than 2 or 3 mm from the electrodes. Ulcerative superficial tumors exposed to air rapidly reduced in size, and a dry eschar that developed fell off at 17 to 25 days.