Evaluating preoperative coagulation panels in dogs undergoing liver lobectomy for primary liver tumors: A multi-institutional retrospective study.

BACKGROUND: The objectives of this study were to: (i) Determine whether operable primary liver tumors were associated with prolongations in prothrombin time (PT) and activated partial thromboplastin time (aPTT) and (ii) determine if these secondary hemostatic abnormalities were more prevalent with specific liver tumors. STUDY DESIGN: Multi-institutional retrospective study. ANIMAL POPULATION: Dogs (n = 359) undergoing liver lobectomy for a primary liver tumor with a preoperative coagulation panel. METHODS: Data was identified via electronic medical record review at eight veterinary teaching hospitals. Baseline dog characteristics, coagulation panel values, platelet count, emergency versus non-emergency procedure, whether the dogs received transfusion(s) of a blood product, liver lobe removed, and histopathological diagnosis were extracted from the medical record. Chi-square analysis was used to compare categorical variables between groups. Continuous variables were assessed for normality using the Shapiro-Wilk test. RESULTS: A total of 74 of 359 dogs (20.6%) had a prolongation in either PT or aPTT preoperatively. A total of 20 of 359 dogs (5.6%) were found to have prolongation of both PT and aPTT. Hemangiosarcoma was the only histopathological diagnosis associated with concurrent prolongations of both PT and aPTT (p < .001) in 6/16 (37.5%) dogs. CONCLUSION: Coagulation panels including PT and aPTT are unlikely to detect substantial deficiencies in secondary hemostasis in most dogs with primary liver tumors except in dogs with a histopathological diagnosis of hemangiosarcoma. CLINICAL SIGNIFICANCE: PT and aPTT testing is low yield as an elective preoperative screening test in dogs with primary liver tumors except in dogs where there is a hemoabdomen or high suspicion for hepatic hemangiosarcoma.

Partial ulnar ostectomy, stereotactic body radiation therapy, and palliative radiation therapy as local limb sparing treatment modalities for ulnar tumors in dogs.

Background: Information on dogs that undergo limb preserving local treatment for ulnar tumors is currently limited. Objective: To describe the clinical characteristics and outcomes in dogs that underwent partial ulnectomy or radiation therapy (RT) for ulnar bone tumors, and to evaluate potential risk factors for outcomes as well as pre-treatment factors for association with treatment modality selected. Animals: Forty client-owned dogs that underwent partial ulnectomy or RT for an ulnar tumor from July 2006 to July 2021. Methods: The medical records database from a single institution were retrospectively reviewed, and data were recorded and analyzed. Results: Radiation therapy was performed in 24 dogs, with 12 stereotactic body RT (SBRT) and 12 palliative RT (PRT) plans, and partial ulnectomy was performed in 16 dogs. Biomechanical complications occurred in 6/12 (50%) dogs that underwent SBRT, 6/12 (50%) dogs that underwent PRT, and 3/16 (18.8%) dogs that underwent ulnectomy. The majority of dogs had a good functional outcome following partial ulnectomy, and no dogs required surgical stabilization of the carpus even with lateral styloid process excision. Pathologic fracture occurred in 4/12 (33.3%) dogs following SBRT and 5/12 (41.7%) dogs following PRT. Local progression or recurrence was documented in 5/12 (41.7%) dogs that underwent SBRT, 2/12 (16.7%) dogs that underwent PRT, and 2/16 (12.5%) dogs that underwent ulnectomy. The overall median survival time was 198 days, and factors that were significantly associated with improved survival time included adjuvant chemotherapy administration and partial ulnectomy as local treatment method for dogs that received chemotherapy. Clinical relevance: Both RT and ulnectomy were effective and well tolerated local treatment modalities for dogs with ulnar tumors.

A retrospective study of canine oral extramedullary plasmacytoma over a 15-year period (July 2004-July 2019): Treatment, histologic parameters and clinical outcomes.

A total of 45 cases of canine oral extramedullary plasmacytomas (EMPs) presented to a tertiary referral institution over a 15-year period were examined. Histologic sections of 33 of these cases were examined for histopathologic prognostic indicators. Patients underwent variable treatment including surgical intervention, chemotherapy and/or radiation therapy. Long term survival was observed in the majority of dogs with a median survival time of 973 days (2-4315 days). However, almost 1/3 of dogs had progression of plasma cell disease, including two cases with myeloma-like progression. Histologic characterization of these tumours did not reveal criteria to predict tumour malignancy. However, cases without tumour progression did not exceed 28 mitotic figures in ten 400× fields (2.37 mm2 ). All cases with tumour related death showed at least moderate nuclear atypia. Oral EMPs may represent a local manifestation of systemic plasma cell disease or singular focal neoplasia.

Sternohyoideus-sternothyroideus muscle flap to reconstruct oronasal fistulas due to maxillary cancer in four dogs.

OBJECTIVE: To describe the repair of oronasal fistulas in dogs treated for maxillary cancer, with a novel sternohyoideus-sternothyroideus muscle flap, and to report the outcome. ANIMALS: Client-owned dogs (n = 4) with oronasal fistulas related to cancer. STUDY DESIGN: Short case series. METHODS: Maxillary defects were caused by tissue destruction by the tumor and tumor response to radiation therapy in two cases and a complication of caudal maxillectomy in two cases, one of which had neoadjuvant radiation therapy. All tumors were >4 cm at the level of the maxilla. Flaps were harvested by transecting the ipsilateral sternothyroideus and sternohyoideus muscles from their origin at the manubrium and costal cartilage. The muscles were rotated around the base of the cranial thyroid artery and tunneled subcutaneously in the neck and through an incision in the caudodorsal aspect of the oral cavity. The muscle flap was sutured to the edges of the oronasal fistula. RESULTS: The flap reached as far rostral as the level of the first premolar without tension. All dogs had clinical signs that improved postoperatively. All dogs had partial dehiscence of the flap. CONCLUSION: This flap was associated with a high rate of complications; however, all flaps were used in challenging cases. Clinical signs related to oronasal fistula were improved in all dogs in this case series.

Potential Seeding From Fine-Needle Aspiration of an Axial Osteosarcoma: A Case Report.

This report describes the first potential case of seeding after fine-needle aspiration (FNA) of a rib osteosarcoma in a dog. An 8-year-old, 28-kg female spayed Golden Retriever was presented to her primary veterinarian with a 3-week history of a 3-cm firm, unpainful, immobile mass arising from the 9th rib. The mass was aspirated and submitted for cytological examination. A subcutaneous nodule developed several days after the FNA was performed in a location immediately overlying but distinct from the primary rib tumor on palpation. Both the primary mass and the newly diagnosed subcutaneous nodule were biopsied and were consistent with an osteosarcoma. Although it cannot be ruled out that the subcutaneous lesion was metastatic, seeding was a reasonable explanation based on where the new mass was located and how quickly it appeared after the FNA was performed. The aim of this case report was to describe the possibility of tumor seeding during FNA for osteosarcoma. It is the authors' opinion that utility of cytological diagnosis of bone tumors outweighs the risk of possible seeding and should continue to be used as a routine diagnostic test for the diagnosis of aggressive bone lesions.

Nasal Smooth Muscle Hamartoma in a Dog: a Novel Subtype.

A 3-year-old, female spayed, Pug-cross dog presented with a 2-year history of nasal congestion and focal facial deformity. Complete surgical excision was elected following nasopharyngoscopy, endoscopic biopsy and subsequent computed tomography (CT) scan. Nasopharyngoscopy revealed a friable, polypoid mass of the right nasal conchae occluding the right nasal passage. Biopsies of the mass showed expansion of the submucosa by dense bundles of well-differentiated smooth muscle cells that were strongly immunoreactive for ⍺-smooth muscle actin and desmin. Post-procedure CT revealed a large space-occupying mass in the nasal cavity with minimal lysis of the adjacent calvarium. Histology following complete excision confirmed the results obtained on the initial endoscopic biopsy. The final diagnosis was smooth muscle hamartoma.

A Contemporary Retrospective Study of Survival in Dogs With Primary Lung Tumors: 40 Cases (2005-2017).

Objective: To report the median survival time in a contemporary cohort of dogs with primary lung tumors and intrathoracic nodal metastasis. Design: Retrospective Case Series. Animals (or sample): Dogs with primary lung tumors treated with lung lobectomy and lymph node biopsy. Procedures: The medical record database at Colorado State University was queried for dogs with primary lung tumors from January 1, 2005 to December 31, 2017. Patients were identified for inclusion if they had lung lobectomy and an intrathoracic lymph node biopsy performed. The median survival time (MST) for lymph node positive (LN+) and negative dogs (LN-) was calculated as well as the MST in dogs that did or did not receive adjuvant chemotherapy. Differences were compared between groups with significance set at p < 0.05. Results: The MST in LN+ dogs (n = 11) was 167 days which was not statistically different from LN- dogs (n = 29) at 456 days (p = 0.2407). No significant difference in the MST in LN+ dogs was identified between dogs that received adjuvant chemotherapy (n = 4; 110 days) and those that did not receive adjuvant chemotherapy (n = 6; 125 days) (p = 0.4409). There was no difference in survival time in LN- dogs receiving chemotherapy (n = 12; 335 days) as compared to those LN- dogs (n = 10) that did not receive adjuvant chemotherapy (258.5 days; p = 0.6475). Conclusions and Clinical Relevance: The survival of primary pulmonary neoplasia in dogs with intrathoracic nodal metastasis is longer than previously reported in this contemporary cohort. Chemotherapy did not appear to improve survival in LN+ or LN- dogs. The combination of tumor size between 100 and 999 cm3 and positive lymph node status significantly reduced survival.

Canine tonsillar neoplasia and tonsillar metastasis from various primary neoplasms.

Tonsillar metastasis from distant primary tumours has not been described in dogs, and reports are rare in humans. The aims of this study were to determine whether tumour metastasis occurs to the canine palatine tonsils and evaluate whether afferent lymphatics drain to the palatine tonsils via skull indirect computed tomography lymphangiography (ICTL). Retrospective review of the diagnostic laboratory tonsillar histopathology submissions was performed. ICTL studies (n = 53) were retrospectively reviewed by a single radiologist. Of 882 total tonsil histopathology samples, 492 (56%) were considered neoplastic, with 8% of them benign. Of the primary malignant neoplasms of the tonsil, squamous cell carcinoma (55%), lymphoma (17%) and melanoma (12%) were most common. Tonsillar metastasis was confirmed in 41 cases; histopathologic evaluation revealed melanoma (25), carcinoma (10), hemangiosarcoma (2) and one each of fibrosarcoma, malignant histiocytosis, basal cell tumour and undifferentiated sarcoma. A total of 53 tonsillar melanoma cases were identified, of which 25 represented metastasis from a known distant primary tumour and 28 were solely tonsillar, with 9 of these cases having concurrent lymph node metastasis. No ICTL cases had lymphatic contrast drainage to the palatine tonsil. The palatine tonsil is an important site of metastasis for a variety of primary tumour types from many locations. ICTL did not reveal lymphatics draining to the palatine tonsil, which is highly supportive of hematogenous route of metastasis to the tonsil. Tonsillar metastasis may be more common than previously thought. It is recommended to perform a thorough oral examination, including the tonsils, for all oral tumours and melanoma cases.

The development of an indirect computed tomography lymphography protocol for sentinel lymph node detection in head and neck cancer and comparison to other sentinel lymph node mapping techniques.

Identification of metastatic disease critically impacts the care and prognosis of patients with neoplasia. Multiple techniques exist for identifying the sentinel or first lymph node(s) that receive draining tumour lymph. Identification of the sentinel lymph node enables accurate tissue sampling for determination of lymphatic metastasis. The aims of this study were to develop a computed tomography (CT) protocol for identifying the sentinel lymph node in dogs with tumours of the head and neck. In addition, indirect CT lymphography was compared to lymphoscintigraphy and vital dye injection to determine which technique more reliably identified the sentinel lymph node. CT indirect lymphography using intratumoral injection of iodinated contrast identified draining lymphatic vessels in eight of 18 dogs and identified the sentinel lymph node in five of 18 dogs. CT indirect lymphography employing four-quadrant peritumoral injection of iodinated contrast identified draining lymphatic vessels in 18 of 20 dogs and identified the sentinel lymph node in 11 of 20 dogs. Vital dye injection and lymphoscintigraphy identified the sentinel lymph node in 17 of 18 and 20 of 20 dogs, respectively. Identified sentinel lymph nodes were either ipsilateral or bilateral to the primary tumour. Both CT techniques were found to be safe and simple. Peritumoral injection has the greatest promise for the detection of sentinel lymph nodes in various head and neck cancers using CT, while lymphoscintigraphy had the greatest success of the compared techniques.

Partial cystectomy with a bipolar sealing device in seven dogs with naturally occurring bladder tumors.

OBJECTIVE: To describe the use of a bipolar sealing device (BSD) for partial cystectomy in dogs undergoing excision of bladder tumors. STUDY DESIGN: Multicenter, prospective, clinical pilot study. SAMPLE POPULATION: Seven client-owned dogs with nontrigonal urinary bladder lesions. METHODS: Dogs underwent a sealed partial cystectomy with a BSD, with or without cystoscopic guidance of the resection. The sealed cystectomy site was oversewn with a single-layer simple continuous pattern with monofilament absorbable suture. RESULTS: Sealed partial cystectomy was successfully performed in all dogs, with a median surgical duration of 69 minutes (range, 50-120). Lesions were located at the apex in six dogs and on the ventral midbody of the bladder in one dog. No urine leakage from the BSD luminal seal was visible prior to suture closure in three dogs, while varying amounts of urine leaked from the sealed site in four dogs. Suture was placed over the seal in grossly normal bladder tissue in six dogs and in the BSD peripheral thermal effect zone in one dog; in this latter dog, revision cystorrhaphy was required 3 days later because of uroabdomen. The other six dogs had no clinical evidence of urinary bladder healing complications. CONCLUSION: The integrity of the seal generated by the BSD tested here on partial cystectomies varied between dogs and was unpredictable. CLINICAL SIGNIFICANCE: Sealed partial cystectomy with a BSD may reduce exposure of urinary bladder luminal contents to the surgical site. However, the placement of sutures over the seal and through grossly normal bladder tissue is recommended to prevent postoperative uroabdomen.

Analysis of outcome in dogs that undergo secondary amputation as an end-point for managing complications related to limb salvage surgery for treatment of appendicular osteosarcoma.

Appendicular osteosarcoma (OSA) remains a prevalent musculoskeletal cancer in dogs and definitive local control followed by adjuvant cytotoxic chemotherapy is considered the gold standard approach. Several studies support surgical limb salvage as a means of local control with similar outcomes compared with limb amputation. Complications are well described for limb salvage but little is known of dogs that undergo secondary amputation as a result of complications and outcomes specific to this group. A retrospective analysis of dogs in an institutional primary bone tumour registry was performed to identify dogs diagnosed with histologically confirmed OSA treated with surgical limb salvage with a technique that required an implant to reconstruct the osseous defect. A total of 192 dogs were identified with 31 dogs undergoing secondary amputation representing a limb preservation rate of 84%. A total of 111 dogs were analysed: 31 secondary amputation cases and 80 controls were selected for comparison. The most common reasons for secondary amputation were local recurrence (LR) and surgical site infection (SSI), with odds ratios of 3.6 and 1.7, respectively. Dogs that underwent secondary amputation had a significantly (P = .05) longer median disease specific survival time (ST) (604 days) compared with the control group (385 days). Dogs lived for a median of 205 days beyond secondary amputation and 97% had good functional outcome. Significant independent factors that positively influenced ST were secondary amputation, moderate SSI, severe SSI and age.

Bilateral caudal maxillectomy for resection of tumors crossing palatal midline and use of the angularis oris axial pattern flap for primary closure or dehiscence repair in two dogs.

OBJECTIVE: To describe the technique and outcomes for bilateral caudal maxillectomy for resection of large caudal maxillary tumors crossing palatal midline in two dogs. STUDY DESIGN: Clinical case report. ANIMALS: Two client-owned dogs. METHODS: Two client-owned dogs with primary caudal maxillary tumors, a poorly differentiated sarcoma, and a multilobulated osteochondrosarcoma. Bilateral caudal maxillectomies were performed for curative-intent resection of these tumors. The angularis oris axial pattern flap was used for primary closure in one dog and for dehiscence repair in the other. RESULTS: Both tumors were resected with complete histologic margins. The defects were closed with local buccal mucosal flaps, with or without a unilateral angularis oris flap. Esophagostomy tubes were placed at time of surgery to bypass oral feeding. Incisional dehiscence and subsequent oronasal fistula formation occurred as a postoperative complication in both dogs (3 and 10 days, respectively). Both were successfully repaired with a combination of local buccal mucosal flaps and the angularis oris flap. Both dogs had good functional outcome and quality of life after recovery from revision surgery. CONCLUSION: Bilateral caudal maxillectomy allowed resection of caudal maxillary tumors crossing palatal midline, with good function and quality of life after recovery in 2 dogs. CLINICAL SIGNIFICANCE: Good outcomes including complete resections are achievable with bilateral caudal maxillectomy despite complications. Local mucosal and axial pattern flaps can be used for dehiscence repair.

Postamputation Orthopedic Surgery in Canine Amputees: Owner Satisfaction and Outcome.

Surgical management of postamputation orthopedic disease (PAOD) in canine amputees has rarely been documented, and no reports describing outcome of stifle surgery in canine amputees are available. The objective of this multisite retrospective case series was to describe cases and evaluate satisfaction with and outcome of postamputation orthopedic surgery in canine amputees. Data was obtained through medical records and owner survey responses; data included signalment, amputation cause, diagnosis, surgical treatment, timeframes, and outcome assessment. Outcome was categorized as acceptable or unacceptable, and complications were classified as catastrophic, major, or minor. Eleven thoracic limb amputees and 6 pelvic limb amputees with surgically treated PAOD were identified. Surgically treated PAOD was reported at a median of 9.7 months (range 0.5-110 months) after amputation. All 17 amputees were treated for pelvic limb disease, predominantly for cranial cruciate ligament disease that occurred in 11 of 17 dogs. Major complications following orthopedic surgeries performed in 3 thoracic limb amputees consisted of infection (n = 2) and uncontrolled pain (n = 1). No major complications were reported following orthopedic surgeries performed in pelvic limb amputees. Acceptable mid-to-long-term outcome was achieved in 16 of the 17 canine amputees. Surgical treatment of pelvic limb disease did not appear to be associated with a high number of major complications in this case series. These findings suggest that orthopedic surgery, specifically stifle surgery, in canine amputees might be considered a feasible treatment option. Although there are inherent methodological limitations of retrospective studies and owner surveys, our case series provides new information that might help guide surgical treatment decisions in canine amputees suffering from orthopedic disease. Prospective studies using objective outcome measures evaluating surgical management of PAOD are necessary to confirm the provided information.

Intraoperative and postoperative complications of partial maxillectomy for the treatment of oral tumors in dogs.

OBJECTIVE To characterize and identify factors associated with intraoperative and postoperative complications of maxillectomy in dogs with oral tumors. DESIGN Retrospective cohort study. ANIMALS 193 dogs that underwent maxillectomy for oral tumor excision from 2000 through 2011. PROCEDURES Data were extracted from the medical records regarding dog signalment, tumor location and size, histologic findings, clinical stage, maxillectomy category, surgical approach, and additional treatments provided. These factors were examined for associations with recorded intraoperative and postoperative outcomes. RESULTS The most common intraoperative complication was excessive surgical bleeding (103/193 [53.4%]), for which 44 (42.7%) dogs received an intraoperative blood transfusion. These outcomes were both significantly associated with tumor size and location, maxillectomy type, and surgical approach. Dogs treated with a dorsolateral combined intraoral surgical approach were more likely to have excessive surgical bleeding (48/58 [83%]) and had a longer mean duration of surgery (106 minutes) than those treated with an intraoral approach (29/54 [54%] and 77 minutes, respectively). Complications developing within 48 hours after surgery included epistaxis (99/193 [51.3%]), excessive facial swelling (71/193 [36.8%]), facial pawing (21/193 [10.9%]), and difficulty eating (22/193 [11.4%]). Complications developing within 48 hours to 4 weeks after surgery included lip trauma (22/164 [13.4%]), oronasal fistula formation (18/164 [11.0%]), wound dehiscence (18/164 [11.0%]), and infection (13/164 [7.9%]). CONCLUSIONS AND CLINICAL RELEVANCE Complications associated with maxillectomy in dogs were generally minor. Aggressive surgical planning, preparedness for hemorrhage and transfusion, careful tissue dissection, and comprehensive pain control are recommended, particularly for dogs with large, caudally located oral tumors requiring extensive excision.

Photodynamic therapy via navigational bronchoscopy for peripheral lung cancer in dogs.

OBJECTIVE: In the setting of lung cancer, photodynamic therapy (PDT) is typically used to treat centrally located endobronchial tumors. The development of navigational bronchoscopy has opened the potential for using PDT to treat peripheral lung tumors. However, there is limited information about the feasibility of this approach for treating peripheral lung cancers, and about its effects on surrounding healthy lung tissue. We studied the use of PDT delivered by electromagnetic navigational bronchoscopy to treat peripheral lung cancer in dogs. MATERIALS AND METHODS: Three dogs with peripheral lung adenocarcinomas were given intravenous porfimer sodium (Photofrin® [Pinnacle Biologics, Inc., Chicago, IL]) to photosensitize the tumors, then navigational bronchoscopy was used to deliver photoradiation. One week after PDT, the tumors and involved lung lobe were surgically excised and evaluated histologically. RESULTS: PDT was successful in all three dogs and was associated with tolerable and manageable adverse effects. Tissue sections from within PDT-treated tumors showed regions of coagulative central necrosis admixed with small numbers of inflammatory cells, and arterial thrombosis. Viable adenocarcinoma was seen in the surrounding areas. CONCLUSION: These results suggest that PDT can be successfully deployed to treat peripheral lung cancers using navigational bronchoscopy. Furthermore, damage to surrounding noncancerous tissues can be minimized with accurate placement of the optical fiber. Studies of this modality to treat peripheral lung cancers in humans may be warranted. Lasers Surg. Med. 50:483-490, 2018. © 2018 Wiley Periodicals, Inc.

Dedifferentiated Chondrosarcoma in the Dog and Cat: A Case Series and Review of the Literature.

This retrospective case series describes seven dogs and one cat diagnosed with dedifferentiated chondrosarcoma, an uncommon, aggressive variant of chondrosarcoma. The purpose of the study is to describe clinical, imaging, and histopathological findings of this tumor. Medical records and the diagnostic laboratory database at Colorado State University from 2000 to 2015 were reviewed and complete medical records were available for the eight animals in this report. Similar to what has been reported in people, poor long-term survival and high metastatic rate, particularly to the lungs, was observed in our case series. A bimorphic pattern on imaging (radiographs, computed tomography, and MRI) consisting of mineralized and nonmineralized areas was seen mirroring the high-grade sarcomatous component adjacent to a low-grade chondroid component seen histopathologically. A review of the human literature including suspected etiology, imaging findings, histopathology, and survival times with various treatment options is presented. This article describes the first reported cases of dedifferentiated chondrosarcoma in the veterinary literature. Early accurate recognition could lead to treatment plans tailored to this variant.

Prognosis for dogs with stage III osteosarcoma following treatment with amputation and chemotherapy with and without metastasectomy.

OBJECTIVE To determine survival times of selected dogs with metastatic (stage III) osteosarcoma, whether disease-free interval (DFI) was associated with survival time after diagnosis of stage III disease (ie, stage III survival time), and whether a survival benefit of metastasectomy existed. DESIGN Retrospective case series with nested cohort study. ANIMALS 194 client-owned dogs treated for histologically confirmed appendicular osteosarcoma from 1997 through 2009. PROCEDURES Dogs were included if they had stage I or II osteosarcoma at the time of initial evaluation, had amputation of the affected appendage and ≥ 1 dose of chemotherapy afterward, and developed metastasis within the follow-up period or prior to death. Data collected from the medical records included signalment, primary tumor location, clinical and laboratory findings, whether metastasectomy was performed, and outcome. Various factors were examined for associations with outcome. RESULTS Dogs that received no treatment for the metastasis had a median survival time between 49 and 57 days after diagnosis of stage III osteosarcoma. Duration of the preceding DFI had no association with this period. Metastasectomy alone was associated with a longer median stage III survival time (232 days) than no metastasectomy (49 days). Among all dogs identified as qualifying for pulmonary metastasectomy on the basis of < 3 pulmonary nodules visible on thoracic radiographs and a DFI > 275 days (n = 21), a survival advantage was also identified for those that actually received pulmonary metastasectomy (6). CONCLUSIONS AND CLINICAL RELEVANCE Preceding DFI had no influence on survival time of dogs with stage III osteosarcoma. Metastasectomy was associated with an increase in survival time for selected dogs.

Docetaxel Accumulates in Lymphatic Circulation Following Subcutaneous Delivery Compared to Intravenous Delivery in Rats.

BACKGROUND: The circulatory pathway for particles deposited outside of blood capillaries has not been well characterized for non-traditionally-delivered chemotherapeutics. MATERIALS AND METHODS: Blood and lymph pharmacokinetics of docetaxel (5 mg/kg) and carboplatin (14 and 28 mg/kg) following subcutaneous (s.c.) versus intravenous (i.v.) delivery were determined in a rodent model with catheterizations of both the thoracic lymphatic duct and jugular vein for prolonged synchronous blood and lymph sampling. RESULTS: Subcutaneous docetaxel demonstrates preferential lymphatic accumulation based on the area under the time-concentration curve (AUC0-24h) whereas i.v. docetaxel resulted in a greater plasma maximum concentration measured (Cmax). The apparent elimination half-life (t1/2) in lymph for docetaxel is greater following i.v. or s.c. delivery compared to t1/2 in blood. Carboplatin demonstrates a dose-dependent increase in plasma Cmax regardless of delivery route; the total carboplatin exposure over 24 h in lymph and plasma are comparable. CONCLUSION: Subcutaneous docetaxel achieves lymphatic accumulation greater than that of i.v. delivery.

Inflow Venous Occlusion for Intracardiac Resection of an Occluding Right Ventricular Tumor.

Use of normothermic venous inflow occlusion enabled removal of an intracardiac tumor in a 4 yr old, 27 kg, spayed female Airedale terrier with a history of appendicular osteosarcoma and recent exertional syncope. Inflow venous occlusion via a median sternotomy thoracotomy without hypothermia was used to access the mineralized mass within the right ventricular outflow tract. Duration of circulatory arrest was 70 s for this beating heart surgery. A circumscribed intracardiac chondrosarcoma tumor was marginally resected in this dog, successfully alleviating exertional syncope and restoring a normal echogenic appearance of the right heart. Asymptomatic intracardiac chondrosarcoma recurrence and pulmonary metastasis was detected at 309 days and cardiopulmonary arrest occurred 372 days following intracardiac surgery. Use of inflow occlusion is a viable technique for select intracardiac tumors in dogs with preoperative planning.