Search Results

You are looking at 71 - 80 of 385 items for :

  • "squamous cell carcinoma" x
  • Refine by Access: All Content x
Clear All

IC 50 Molar concentration of compound that inhibits specific activity by 50% ICP-MS Inductively coupled plasma mass spectrometry SCC Squamous cell carcinoma T max Time to maximum plasma concentration Vdss Volume of distribution at steady state

Full access
in American Journal of Veterinary Research

Objective

To characterize the frequency, clinical signs, biologic behavior, and response to treatment of tumors of the ear canal in dogs and cats.

Design

Retrospective analysis of medical records.

Animals

Medical records of 81 dogs (48 malignant tumors, 33 benign tumors) and 64 cats (56 malignant tumors, 8 benign tumors).

Procedure

Data were analyzed for cats and dogs with malignant tumors, and risk factors were analyzed for their potential impact on survival time.

Results

Malignant tumor types most commonly reported included ceruminous gland adenocarcinoma, squamous cell carcinoma, and carcinoma of undetermined origin. Median survival time of dogs with malignant aural tumors was > 58 months, whereas that of cats was 11.7 months. A poor prognosis was indicated by extensive tumor involvement (dogs) and by neurologic signs at time of diagnosis, diagnosis of squamous cell carcinoma or carcinoma of undetermined origin, and invasion into lymphatics or blood vessels (cats).

Clinical Implications

Malignant tumors of the ear canal in dogs and cats have a propensity for local invasion, but tend not to metastasize. Squamous cell carcinoma and carcinoma of undetermined origin were the most locally aggressive tumors. Malignant tumors of the ear canal are best managed by aggressive surgical excision. Radiotherapy may be useful when tumors cannot be completely removed. (J Am Vet Med Assoc 1996;208:1413-1418)

Free access
in Journal of the American Veterinary Medical Association

Summary:

Twenty horses with 30 lesions were studied to evaluate the effects of intratumoral chemotherapy with cisplatin in sesame oil on equine sarcoids (n = 19), squamous cell carcinomas (n = 7), and squamous cell papillomas (n = 4). Treatment consisted of 4 sessions of intratumoral cisplatin chemotherapy at 2-week intervals. A controlled-release formulation of cisplatin in sesame oil was used to limit drug egress from the injection site. Mean dosage per session was 0.97 (±0.17, sem) mg of cisplatin/cm3 of tumor tissue treated for tumor volumes ranging from 10 to 20 cm3. Dosage tended to be slightly higher for smaller tumors and slightly lower for larger tumors. Tumor regression was observed in all horses. Complete response was observed in 18 of the sarcoids, 5 of the squamous cell carcinomas, and 4 of the squamous cell papillomas. The mean relapse-free interval was 21.6 and 14 months in horses with sarcoid and carcinoma/papilloma, respectively. The 1-year relapse-free rates were 87 and 65% for equine sarcoid and carcinoma/papilloma, respectively. In horses with relapse, 70% had tumor recurrence outside the treated field. Cisplatin-related local toxicosis was minimal. Intratumoral cisplatin chemotherapy was found to be a practical and effective treatment of sarcoid and squamous cell carcinoma/papilloma in horses.

Free access
in Journal of the American Veterinary Medical Association

Abstract

Objective—To determine outcome of horses in which cutaneous masses were removed with a carbon dioxide laser.

Design—Retrospective study.

Animals—32 horses.

Procedure—Medical records of horses with 1 or more cutaneous masses treated with a carbon dioxide laser were examined. Follow-up information was obtained through telephone interviews with owners and referring veterinarians.

Results—Cutaneous masses were classified as sarcoids (15 horses), neoplastic masses other than sarcoids (squamous cell carcinoma [9]; fibroma [1]; and melanoma [1]), and nonneoplastic masses (6). Minimum follow-up time was 6 months. Five sarcoids and 2 squamous cell carcinomas recurred. Seven (21%) horses had complications associated with dehiscence of wounds that had been closed primarily or failure of wound healing because of recurrence of the mass. Twenty-six (81%) owners were satisfied with the cosmetic appearance following surgery.

Conclusion and Clinical Relevance—Results suggest that a carbon dioxide laser may be effective for treatment of cutaneous masses in horses. (J Am Vet Med Assoc 2002;220:1192–1197)

Full access
in Journal of the American Veterinary Medical Association

Abstract

Objective

To determine whether feline cells were able to convert 5-aminolevulinic acid (ALA) to protoporphyrin IX (PpIX) in vivo and in vitro, whether IV administration of ALA to healthy cats resulted in adverse effects, and whether PpIX accumulated in a squamous cell carcinoma (SCC) of a cat.

Animals

4 healthy adult cats and 1 adult cat with a cutaneous SCC.

Procedure

In vitro production of PpIX was determined by incubating Crandell feline kidney cells with ALA. Effects of ALA administration and in vivo production of PpIX were determined by administering ALA (100, 200, or 400 mg/kg of body weight) to healthy cats and collecting skin biopsy specimens for up to 24 hours after drug administration. Blood samples were collected for CBC and serum biochemical analyses, and necropsies were performed. Accumulation of PpIX in a SCC was determined by treating a cat with a facial SCC with ALA and collecting specimens of the tumor and adjacent grossly normal skin.

Results

Incubation of ALA with feline cells resulted in time- and dose-dependent cytoplasmic accumulation of PpIX in vitro. After IV ALA administration, PpIX was detected in all tissues examined, with the highest fluorescence intensity in epithelia and in squamous cell carcinoma. The tumor-to-skin fluorescence intensity ratio was 5. All cats developed hepatotoxicoses.

Conclusions and Clinical Relevance

Results from this limited number of cats suggest that ALA may be a useful photosensitizer in cats, but that doses > 100 mg/kg, IV, may not be safe. (Am J Vet Res 1999;60:1364–1370)

Free access
in American Journal of Veterinary Research

Objective—

To identify ocular and adnexal diseases to which llamas in North America are susceptible, to determine prevalence of these diseases in llamas, and to compare prevalences of the major ocular diseases of llamas, cattle, and horses.

Design—

Retrospective study.

Animals—

194 llamas, 4,937 cows, and 11,950 horses with ocular disease.

Procedure—

Medical records of all llamas entered into the Veterinary Medical Database between 1980 and 1993 were reviewed. Data on ocular structures affected and types of ocular disease were compiled. Prevalences of uveitis, corneal ulcers, and ocular squamous cell carcinoma in llamas were compared with prevalences in cattle and horses.

Results—

194 of 3,243 (6%) llamas had at least 1 ocular disease. The proportion of llamas that had ocular disease was significantly higher lhan the proportions of cattle or horses. The most frequently affected ocular structure in llamas was the cornea, and ulcerative keratitis was the most common comeal disease. The second most commonly affected structure was the uveal tract. Cataracts were reported in 20 (10%) of the llamas with ocular problems. Eyelid disorders, retinal diseases, glaucoma, and ocular or adnexal neoplasia were reported infrequently in llamas.

Clinical Implications—

Results suggest that corneal disease is common in llamas and is usually secondary to trauma. Uveitis may also be common in llamas, but llamas do not appear to be highly susceptible to glaucoma, ocular neoplasia, or to direct corneal invasion by bacteria such as Moraxefla sp. (J Am Vet Med Assoc 1997;210:1784–1787)

Free access
in Journal of the American Veterinary Medical Association

Abstract

Objective

To determine prevalence of p53 tumor suppressor protein overexpression in spontaneously arising tumors of dogs, using the CM-1 polyclonal antibody and immunohistochemical methods.

Design and Sample Population

Retrospective analysis was performed on archived, paraffin-embedded tumor tissue from dogs. A total of 226 tumors were evaluated, including tumors of epithelial, mesenchymal, and round cell origins.

Procedure

Overexpression of p53 was detected by indirect immunohistochemical methods, using the CM-1 rabbit anti-human p53 polyclonal primary antibody. Protein overexpression was determined by use of a grading system based on percentage of stained tumor nuclei.

Results

Nuclear overexpression of p53 was detected in most squamous cell carcinomas, nasal ade-nocarcinomas, and perianal gland adenocarcinomas. Hemangiopericytomas, transitional cell carcinomas, mammary adenocarcinomas, apocrine gland adenocarcinomas, intestinal adenocarcinomas, mast cell tumors, and cutaneous histiocytomas had low numbers of nuclei overexpressing p53. Remaining tumor types had intermediate p53 nuclear overexpression. Cytoplasmic staining was observed in some carcinomas, particularly intestinal adenocarcinomas.

Conclusions

Overexpression of p53 is common in spontaneously arising neoplasms of dogs.

Clinical Relevance

Prospective determination of p53 status in some tumor types may be as clinically useful in determining prognosis and predicting survival times for dogs with cancer as it is for human beings with cancer. (Am J Vet Res 1997;58:857–863)

Free access
in American Journal of Veterinary Research

Summary

Estrogen and progesterone receptors (er, pr) were measured in cytosol fractions from 18 primary canine mammary carcinomas by use of biochemical assays. One or both receptors were detected (> 10 fmol/mg of cytosol protein) in 11 tumors: 5 er and pr; 2 er only; 4 pr only. Mean cytoplasmic receptor concentrations (fmol/mg of cytosol protein) were 22.8 ± 2.9 (sem) for er and 51.0 ± 10.3 for pr in tumors containing er and pr, 28.8 ± 12.1 for er in tumors containing only er and 13.2 ± 1.5 for pr in tumors containing only pr. Estrogen or progesterone receptors or both were identified in 6 of 9 tubular adenocarcinomas, 4 of 5 papillary adenocarcinomas, and 1 of 1 squamous cell carcinoma. These receptors were not identified in solid carcinomas (n = 2) or a single spindle cell carcinoma. Although the number of cases was limited, survival times of dogs tended to be longest in those with tumors containing er alone or in combination with pr, intermediate in those with tumors containing only pr, and shortest in those with tumors without er or pr. A correlation was not apparent between receptor status and age, presence of ovaries, tumor size, or histologic classification of the tumor. In the analysis of this series, the extent of surgery (mastectomy of the involved gland vs unilateral or bilateral mastectomy) did not appear to influence the outcome of the disease, and metastasis to regional lymph nodes did not appear to be a reliable prognostic indicator.

Free access
in American Journal of Veterinary Research

SUMMARY

Piroxicam and other nonsteroidal anti-inflammatory drugs (nsaid) have antitumor activity against naturally acquired cancer in dogs and human beings, and against experimentally induced tumors in rodents. We are investigating potential mechanisms of nsaid antitumor activity. The direct cytotoxicity of piroxicam, indomethacin, and aspirin against 4 canine tumor cell lines (transitional cell carcinoma, squamous cell carcinoma, melanoma, and soft tissue sarcoma) was determined in short-term growth rate assays and in clonogenic assays. Piroxicam was evaluated alone and in combination with the lipoxygenase inhibitor zileuton, and in combination with the chemotherapeutic agents cisplatin and carboplatin. The 50% inhibitory concentrations (lC50) against melanoma cells in short-term growth rate assays were: 530 μM piroxicam, 180 μM indomethacin, and greater than 1 mM aspirin. These IC50 values were over 10 times greater than serum concentrations of these drugs that could safely be achieved in vivo. The IC50 of zileuton combined with piroxicam (280 μM) was not different from the IC50 of zileuton alone (230 μM; anova P = 0.47) in melanoma cells. Similarly, addition of piroxicam did not alter the IC50 of either cisplatin (1.6 μM) or carboplatin (6.1 μM). These results suggest that nsaid, at serum concentrations achievable in vivo, do not have direct cytotoxicity against canine tumor cells tested. It is unlikely that the in vivo antitumor activity of nsaid is attributable to a direct cytotoxic effect.

Free access
in American Journal of Veterinary Research

Summary

One hundred twenty-six dogs with histologically confirmed, measurable malignant tumors were evaluated in a prospective study to determine the response to the antineoplastic drug mitoxantrone. Ninety-five dogs had been refractory to one or more treatment modalities (surgery, n = 57; chemotherapy other than mitoxantrone, n = 37; radiation, n = 4; whole body hyperthermia, n = 1). The extent of neoplastic disease was determined immediately before each dose of mitoxantrone was administered (1 to 10 doses, 2.5 to 5 mg/m2 of body surface area, iv) 21 days apart. Each dog was treated with mitoxantrone until the dog developed progressive disease or until the dog's quality of life diminished to an unacceptable level as determined by the owner or attending veterinarian.

A partial or complete remission (>50% volume reduction) was obtained in 23% (29/126) of all dogs treated. Tumors in which there was a partial or complete remission included lymphoma (11/32), squamous cell carcinoma (4/9), fibrosarcoma (2/9), thyroid carcinoma (1/10), transitional cell carcinoma (1/6), mammary adenocarcinoma (1/6), hepatocellular carcinoma (1/4), renal adenocarcinoma (1/1), rectal carcinoma (1/1), chondrosarcoma (1/2), oral malignant melanoma (1/12), cutaneous malignant melanoma (1/1), myxosarcoma (1/1), mesothelioma (1/1), and hemangiopericytoma (1/1).

Our results indicated that mitoxantrone induces measurable regression in various malignant tumors in dogs.

Free access
in Journal of the American Veterinary Medical Association