Primary intrapelvic hemangiosarcoma in a dog.

A 12-year-old, spayed female Schnauzer presented with constipation. A mass was observed in the pelvic cavity, and metastasis was not identified. Mass resection was performed through celiotomy with pubic osteotomy, and hemangiosarcoma was diagnosed. At 10 weeks post-operatively, the patient died of multiple metastasis. Primary intrapelvic hemangiosarcoma is rare in dogs.

DOSIMETRIC CONSEQUENCES OF USING CONTRAST-ENHANCED COMPUTED TOMOGRAPHIC IMAGES FOR INTENSITY-MODULATED STEREOTACTIC BODY RADIOTHERAPY PLANNING.

Potential benefits of planning radiation therapy on a contrast-enhanced computed tomography scan (ceCT) should be weighed against the possibility that this practice may be associated with an inadvertent risk of overdosing nearby normal tissues. This study investigated the influence of ceCT on intensity-modulated stereotactic body radiotherapy (IM-SBRT) planning. Dogs with head and neck, pelvic, or appendicular tumors were included in this retrospective cross-sectional study. All IM-SBRT plans were constructed on a pre- or ceCT. Contours for tumor and organs at risk (OAR) were manually constructed and copied onto both CT's; IM-SBRT plans were calculated on each CT in a manner that resulted in equal radiation fluence. The maximum and mean doses for OAR, and minimum, maximum, and mean doses for targets were compared. Data were collected from 40 dogs per anatomic site (head and neck, pelvis, and limbs). The average dose difference between minimum, maximum, and mean doses as calculated on pre- and ceCT plans for the gross tumor volume was less than 1% for all anatomic sites. Similarly, the differences between mean and maximum doses for OAR were less than 1%. The difference in dose distribution between plans made on CTs with and without contrast enhancement was tolerable at all treatment sites. Therefore, although caution would be recommended when planning IM-SBRT for tumors near "reservoirs" for contrast media (such as the heart and urinary bladder), findings supported the use of ceCT with this dose calculation algorithm for both target delineation and IM-SBRT treatment planning.

Hemipelvectomy: outcome in 84 dogs and 16 cats. A veterinary society of surgical oncology retrospective study.

OBJECTIVE: To report clinical findings, perioperative complications and long-term outcome in dogs and cats that had hemipelvectomy surgery for treatment of neoplasia. STUDY DESIGN: Multi-institutional retrospective case series. ANIMALS: Dogs (n = 84) and cats (16). METHODS: Medical records (January 2000 to December 2009) of dogs and cats that had hemipelvectomy at participating institutions were reviewed. Postoperative progress and current status of the patient at the time of the study was determined by either medical record review, or via telephone contact with the referring veterinarian or owner. RESULTS: Complications were infrequent and usually minor. Hemorrhage was the main intraoperative complication; 2 dogs required blood transfusion. One dog developed an incisional hernia. In dogs, hemangiosarcoma had the worst prognosis with a median survival time (MST) of 179 days. MST for chondrosarcoma (1232 days), osteosarcoma (533 days), and soft tissue sarcoma (373 days) were not statistically different. Median disease-free interval (DFI) for local recurrence of all tumor types was 257 days. Cats had 75% survival at 1 year, which was significantly longer than dogs. CONCLUSIONS: Survival times for most tumor types can be good, but surgical margins should be carefully evaluated to ensure complete tumor removal. Adjuvant therapies may be advisable particularly for dogs to reduce rates of local recurrence or distant metastasis.

Computed tomographic characteristics of intrapelvic masses in dogs.

In people, the computed tomography (CT) characteristics of intrapelvic masses can be used to distinguish a malignant from a benign mass. As prognosis varies greatly between malignant and benign intrapelvic masses, knowledge of their biological behavior can aid treatment planning before surgery. The purpose of this study was to determine if CT characteristics exist to help differentiate benign from malignant intrapelvic masses in dogs. The CT images of 14 dogs with a histopathologically confirmed intrapelvic mass were evaluated. Postcontrast internal heterogeneity of the mass was the only characteristic significantly associated with malignancy (P = 0.005). Preoperative CT examination of intrapelvic masses in dogs can provide prognostic information before invasive surgical treatment.

Malignant pilomatricoma in a soft-coated Wheaten Terrier.

A 3-year-old, castrated male, soft-coated Wheaten Terrier was presented for evaluation of mild lameness, fecal incontinence, lumbosacral pain, and lack of anal tone. Magnetic resonance imaging scan showed a large (8 x 6 x 5 cm) mass invading and expanding the pelvic bones, sacrum, and associated structures. A fine-needle aspirate of the mass contained many neoplastic cells with high nuclear to cytoplasmic ratios and rare spindle and inflammatory cells. The neoplastic cells were 12-16 mum in diameter, round to cuboidal, basaloid in appearance, and arranged both individually and in loosely cohesive clusters with variably distinct cell borders. Given the location, signalment, and cytologic findings, differential interpretations included a primitive embryonal tumor (eg, neuroblastoma or nephroblastoma in an atypical location) or poorly differentiated carcinoma. The owner elected euthanasia due to the poor prognosis. Abnormal gross findings on necropsy included the pelvic mass and multiple firm, pale, pink-tan nodules in the lung, which proved to be metastases. On histologic examination, the mass and nodules were composed of irregular islands, lobules, and nests of basaloid cells, which transitioned abruptly into large lakes of "ghost" cells with areas of ossification and calcification, consistent with a diagnosis of malignant pilomatricoma. This unusual presentation of a pilomatricoma adds to our knowledge of expected cytologic findings for this tumor.

Pelvic lymphoma as a cause of urethral compression in a mare.

A 6-year-old mare was presented for evaluation of dysuria and pollakiuria. A pelvic mass, which caused obstruction of urinary outflow, was identified. Evidence of renal failure was also present. Due to poor prognosis the mare was euthanized. A postmortem examination revealed a pelvic lymphoma that surrounded and compressed the urethra.

Mammary adenocarcinoma in a chipmunk (Tamias sibiricus).

An 8-year-old, female chipmunk (Tamias sibiricus), which had been kept as a pet, was presented with a chief complaint of the gradually enlarging mammary mass and dysuria. The mammary mass was surgically excised and was histopathologically diagnosed as mammary adenocarcinoma. Despite a general improvement in its condition and reduced dysuria after surgery, the chipmunk died on postoperative day 188. Pathological examination revealed that the mammary tumor had metastasized to both the lungs and the pelvic cavity. The metastatic focus in the pelvic cavity involved the left ureter, with ipsilateral hydronephrosis. Immunohistochemically, the tumor cells were stained positive for cytokeratin (CK) AE1/AE3 and partially positive for CK7, but negative for CK20. This is the first report of a mammary tumor in chipmunks.

Myxomatous neoplasms in the perineal region of baboons.

BACKGROUND: In baboons, Papio sp. neoplasms tend to affect the hematopoietic system most commonly, with rare documentation of myxomatous neoplasms. In contrast, women can develop myxomatous masses within deep peripelvic tissues with some frequency during their reproductive years. METHODS: We have identified and examined, retrospectively, myxomatous perineal masses in twelve female baboons within one research facility and compared their histopathologic, immunohistochemical and electron microscopic features to their human variants. RESULTS: Our results indicate that these myxomatous neoplasms, in humans and non-human primates, share common features. CONCLUSION: Further research, particularly molecular genetic analysis, may be needed to identify the baboon as a true animal model for myxomatous perineal neoplasms.

Intra-pelvic chondrolipoma in a dog.

An 11-year-old male dog with dysuria-stranguria, progressing to anuria, had a multilobulated, firm mass in the perineal area, embedded in the fibroconnective adipose tissue of the pelvic cavity. The mass, which was resected surgically, was unencapsulated and composed of multiple islands of hyaline cartilage, interspersed with mature adipose tissue, and myxoid and fibrous tissues. Foci of chondroid metaplasia were present. Histological and immunohistochemical examination confirmed the mesenchymal origin of the tumour. A diagnosis of intra-pelvic chondrolipoma was made.

Primary haemangiopericytoma in the pelvic cavity of a dog.

A 9-year-old female Yorkshire terrier with lameness of the hind leg was examined at the local animal hospital in Gwangju, Republic of Korea on March, 2004. The radiological findings revealed a mass between the urinary bladder and cervix of the uterus. The encapsulated pelvic mass, measuring 4.0 x 3.0 x 2.5 cm was surgically removed. Grossly, the mass was white and firm and microscopically showed a perivascular whorled pattern of spindle cells. By immunohistochemistry, tumour cells tested positive for vimentin and alpha-smooth muscle actin, and negative for desmin, S-100, lysozyme and cytokeratin. The tumour was diagnosed both histologically and immunohistochemically as a haemangiopericytoma. There were no signs of recurrence within 12 months after surgery. This is the first case report of a haemangiopericytoma in the pelvic cavity of a dog.

Estudo retrospectivo de osteossarcoma primário dos ossos da pelve em cães em um período de 14 meses / Retrospective study of primary osteosarcoma in pelvis's bones of dogs during a period of fourteen months

O osteossarcoma (OSA) é um dos tumores malignos mais comum em cães. Geralmente acomete cães de raça grande e gigante, com idade média de sete anos. Esta neoplasia envolve, freqüentemente, a metáfise de ossos longos, sendo indicado à amputação radical do membro, acrescido de quimioterapia com cisplatina. A terapêutica desta neoplasia com localização na pelve toma-se difícil e normalmente não aceita pelos proprietários. O presente trabalho relata a incidência de osteossarcoma primário em ossos da pelve em cães, durante um período de 14 meses. Dos oito animais atendidos com esta neoplasia, observou-se maior freqüência nos cães da raça Rottweiler e Pastor Alemão. Dentre os ossos que compõem a pelve do animal se observou maior incidência de OSA acometendo o ílio (6 casos). Claudicação, impotência funcional de membro pélvico e dor foram os principais sinais clínicos observados. Em sete casos encontrou-se estágio avançado de comprometimento ósseo na imagem radiográfica, evidenciado, principalmente, pela lise da cortical óssea. Todos os animais foram submetidos à eutanásia por não apresentarem possibilidade de tratamento cirúrgico (hemipelvectomia) com margem de segurança. Também se levou em consideração para esta decisão à condição clínica dos pacientes, as chances de conferir melhora na qualidade de vida dos cães e a opção dos proprietários frente ao prognóstico.

The osteosarcoma (OSA) is one of the most common malignant tumors of dogs. Large and giant -breed dogs are affected and the mean age of these dogs is about 7 years. The tumor usually involves the metaphyses of long bones and the treatment is radical amputation and chemotherapy with cisplatin. The therapy of neoplasia located in pelvis is difficult and usually don't accept by owners. This report describes the incidence of primary osteosarcoma in pelvis of dogs, duting a period of fourteen months. Of the eight animals taken care with this neoplasia, a bigger frequency in the dogs of the race Rottweiler and German Pastor was observed. Amongst the bones that compose animal's pelvis was observed greater osteosarcoma incidence in ileum (6 cases). Lameness, functional impotence of pelvic member and pain had been the main observed clinical signals. In seven cases was found advanced involvement osseous, mainly, for lyses of the cortical. All the animals had been submitted to the euthanasia for not presenting possibility of surgical treatment with safety margin. Also one was taken in consideration for this decision to the clinical condition of the patients, the possibilities to confer improvement in the quality of life of the dogs and the option of the owners' front to the prognostic.

Osteosarcoma at the site of a triple pelvic osteotomy in a dog.

An osteosarcoma (OSA) involving the right pelvis was diagnosed in a 12-year-old golden retriever 11 years after triple pelvic osteotomy (TPO) surgery. The dog was presented with a 12-week history of nonweight-bearing lameness of the right hind limb. Radiographs demonstrated an aggressive bone lesion of the right ilium with profound periosteal proliferation and punctate lysis that extended along the ilium caudally and into the right ischium, with its epicenter at the level of the right TPO plate. Necropsy revealed that the entire right hemipelvis, especially the ischium, was markedly thickened and firm with irregular margins. Histopathology was consistent with a diagnosis of OSA.

[Malignant melanoma of the pelvis as a possible cause of pelvic limb lameness in two gray mares]. / Maligne melanoom in het bekken als mogelijke oorzaak van een bewegingskreupelheid in het achterbeen bij twee schimmelkleurige paarden.

Two grey mares, a 12-year-old Arabian and a 13-year-old Lippizaner cross, were referred for chronic pelvic limb lameness and abduction of the limb during the non supporting phase of the stride. The clinical examination revealed melanomas under the tail and on the perineum, and oedema of the proximal lame limb. A mass in the pelvic area was detected on rectal palpation. Laparoscopy was performed and the provisional diagnosis of malignant melanoma was made. Histological examination of the biopsy taken under laparoscopic control from the mass in the pelvis confirmed the diagnosis of malignant melanoma. In the postmortem examination a large black mass in the pelvis and metastases in several organs were diagnosed. The process under the tail showed microscopically the characteristics of dermal melanomatosis. The metastases showed the appearance of a malignant melanoma. The lameness and abduction during the non supporting phase of the stride were possibly caused by a combination of pain, a mechanical limitation, and paresis/paralysis. When an older grey horse with melanomas on the predilection sites is submitted with pelvic limb lameness and abduction of the limb during the non supporting phase of the stride, a malignant melanoma in the pelvis is one of the differential diagnoses and a rectal examination should be performed. Diagnostic laparoscopy in the standing horse can be useful to confirm the provisional diagnosis.

Endometriosis in cynomolgus monkeys retired from breeding.

Twenty-seven cases of endometriosis were found in 94 female cynomolgus monkeys retired from breeding. The ages of the affected monkeys (28.7% of all the monkeys) ranged from 11 years to 23 years of age with an average of 15.3 years. There was no significant difference in the incidence of endometriosis between groups which had or had not undergone a cesarean section. Time after the last pregnancy was significantly longer in the affected monkeys than in the non-affected ones. These cases were histopathologically classified into four types: 1) pelvic endometriosis with formation of endometrial cysts (51.8% of the affected monkeys), 2) pelvic endometriosis invading other organs without formation of endometrial cysts (3.7%), 3) uterine adenomyosis (22.2%), 4) combined pelvic endometriosis and uterine adenomyosis (22.2%).

Synovial sarcoma in a dog.

Synovial sarcoma is an uncommon malignant tumour of mesenchymal origin, occurring mainly in the vicinity of a joint. Subsequent invasion of the joint and adjacent bones may occur. Less frequently the tumour may be localized in soft tissues remote from joints. Synovial sarcoma usually affects male middle-aged dogs of large breeds. The rate of tumour growth can vary from very slow to very rapid. The tumour is usually poorly defined and infiltrates the deeper structures. Metastasis and recurrence are common. Wide-field surgical excision of the tumour or amputation of the affected limb are the most frequently used forms of treatment. In the present case the dog, a 7-year-old male Alsatian, had a slowly growing tumour in the vicinity of the hip joint, bilaterally. There was no involvement of the bones surrounding the tumour. Surgical resection was performed and one year later the dog was reported to be normal.

Morphological characteristics of spontaneous endometriosis in the baboon (Papio anubis and Papio cynocephalus).

The histopathology of spontaneous endometriosis was studied on 20 pelvic implants biopsied at laparoscopy in 15 healthy baboons. Endometriosis was confirmed by histopathology in 10 of these animals (66%). Typical (n = 3) and subtle (n = 13) endometriotic lesions were confirmed by histopathology in 100 and 61%, respectively. Suspected disease-bearing lesions (n = 4) were confirmed in 50%. Implants could be classified as active (n = 5), inactive (n = 3), atrophic (n = 2) or stromal endometriosis (n = 3). The histological findings for typical and subtle implants were similar to those reported in humans.