Simultaneous UPLC-MS/MS Determination of 6-mercaptopurine, 6-methylmercaptopurine and 6-thioguanine in Plasma: Application to the Pharmacokinetic Evaluation of Novel Dosage forms in Beagle Dogs

2020 ◽  
Vol 26 (46) ◽  
pp. 6013-6020
Author(s):  
Jiaqi Han ◽  
Shenghui Mei ◽  
Jiamin Xu ◽  
Dongjie Zhang ◽  
Siyao Jin ◽  
...  
Keyword(s):  
Formic Acid ◽  
Lymphoblastic Leukemia ◽  
Ultra Performance Liquid Chromatography ◽  
Dosage Forms ◽  
Individual Therapy ◽  
Pharmacokinetic Parameters ◽  
Beagle Dogs ◽  
Detection Range ◽  
Significant Difference ◽  
Pharmacokinetic Evaluation

Background: 6-Mercaptopurine (6-MP) is widely used to treat pediatric acute lymphoblastic leukemia (ALL). Mini-tablets of 5 mg per tablet were developed for precision individual therapy for children and individuals with poor thiopurine S-methyltransferase (TPMT) or nucleoside diphophate-linked moiety X-type motif 15 (NUDT15) metabolism. This study investigated the pharmacokinetic profiles of mini-tablets and conventional tablets with an improved ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method. Methods: After giving 8 healthy beagle dogs 50 mg 6-MP in different dosage forms, plasma samples collected at different time points were analyzed for pharmacokinetic evaluation. The samples were precipitated by methanol with 0.05% formic acid and separated on a Waters Atlantis T3 column (2.1 × 150 mm, 3 μm particles) using 0.1% formic acid in water and methanol at a flow rate of 0.4 mL/min in 4 min. Results: This method showed good linearity, accuracy, precision and stability with a detection range of 5.0-500.0 ng/mL for 6-MP, 6-methylmercaptopurine (6-MMP) and 6-thioguanine (6-TG). The main parameters, half-life of apparent terminal disposition, maximum observed plasma concentration, total AUC extrapolated to infinity, AUC since initiation of the experiment, mean residence time, distribution volume and clearance were 1.62 ± 0.87 hours, 90.58 ± 60.43 ng/mL, 151.20 ± 94.18 ng·h/mL, 292.06 ± 184.02 ng·h2/mL, 1.90 ± 0.92 hours, 864.08 ± 538.52 L, and 432.75 ± 360.64 L/h for conventional tablets and 1.70 ± 1.10 hours, 84.15 ± 39.50 ng/mL, 147.70 ± 51.80 ng·h/mL, 300.92 ± 124.48 ng·h2/mL, 2.07 ± 0.50 hours, 756.90 ± 324.00 L, and 340.75 ± 125.81 L/h for minitablets, respectively. Paired t-tests showed no significant difference in any of the evaluated pharmacokinetic parameters between the two types tablets (P > 0.05). Conclusion: Two dosage forms showed the same pharmacokinetic characteristics. This developing, novel formulation will help to provide a more accurate and optimal dosing regimen of 6-MP for humans in the future.

scholarly journals The Effect of Posaconazole and Isavuconazole on the Pharmacokinetics of Erdafitinib in Beagle Dogs by UPLC-MS/MS

2021 ◽  
Vol 12 ◽  
Author(s):  
Lan-hong Ruan ◽  
Ling-ling Fan ◽  
Kun Wang ◽  
Wan-qi Zhang ◽  
Xiao-jun Wang ◽  
...  
Keyword(s):  
Ultra Performance Liquid Chromatography ◽  
Self Control ◽  
Pharmacokinetic Parameters ◽  
Beagle Dogs ◽  
Limit Of Quantification ◽  
Dog Plasma ◽  
Liquid Chromatography Tandem Mass ◽  
Group A ◽  
Group B ◽  
Second Period

Objective: A robust, quick, and reliable ultra-performance liquid chromatography–tandem mass spectrometry (UPLC-MS/MS) method for the quantification of erdafitinib in beagle dog plasma was developed and validated to evaluate the changes of posaconazole and isavuconazole on the pharmacokinetics of erdafitinib in beagle dogs, respectively.Methods: This experiment adopted a three-period self-control experimental design. In the first period (group A), erdafitinib was orally administered to six beagle dogs at a dose of 4 mg/kg. In the second period (group B), the same six beagle dogs were orally given posaconazole at a dose of 7 mg/kg, and after 30 min, erdafitinib was orally given. In the third period (group C), isavuconazole at a dose of 7 mg/kg was given orally, and then, erdafitinib was orally given. At the different time points after erdafitinib was given in the three periods, the blood samples were collected. The concentration of erdafitinib was detected by the developed UPLC-MS/MS method. DAS 2.0 was used to calculate the pharmacokinetic parameters of erdafitinib.Results: Erdafitinib had a good linear relationship in the range of 1–500 ng/ml, and the lower limit of quantification was 1 ng/ml. The precision, accuracy, extraction recovery, matrix effect, and stability meet the requirements of the guiding principles. After erdafitinib was combined with posaconazole, the Cmax and AUC0→t of erdafitinib increased by 27.19% and 47.62%, respectively, and the t1/2 was prolonged to 6.33 h. After erdafitinib was combined with isavuconazole, the Cmax and AUC0→t of erdafitinib increased by 23.13% and 54.46%, respectively, and the t1/2 was prolonged to 6.31 h.Conclusion: A robust and reliable UPLC-MS/MS method was fully optimized and developed to detect the plasma concentration of erdafitinib in beagle dogs. Posaconazole and isaconazole could inhibit the metabolism of erdafitinib in beagle dogs and increase the plasma exposure of erdafitinib.

scholarly journals Influences of Oldenlandia diffusa on the CYP450 Activities in Rats Using a Cocktail Method by UHPLC-MS/MS

2018 ◽  
Vol 2018 ◽  
pp. 1-6 ◽  
Author(s):  
Yiping Lin ◽  
Yanli Wei ◽  
Xiaoxia Hu ◽  
Meilling Wu ◽  
Xiaoqian Ying ◽  
...  
Keyword(s):  
Ultra Performance Liquid Chromatography ◽  
Metabolic Enzyme ◽  
Pharmacokinetic Parameters ◽  
Mass Spectrometry Detection ◽  
Chromatography Tandem Mass Spectrometry ◽  
Significant Difference ◽  
Liquid Chromatography Tandem Mass ◽  
Clinical Drug ◽  
Oldenlandia Diffusa

Oldenlandia diffusa has been used to treat various cancers. Cytochrome P450, a drug metabolic enzyme, might be influenced by herbal medicine. Currently, the problem that remains is the effective treatment in drug-drug interaction situation. Potential influences of Oldenlandia diffusa were elucidated on the CYP450 activities in rats using a cocktail method. Blood samples were precipitated by acetonitrile. Quantitative determination of target test object was done by ultra-performance liquid chromatography tandem mass spectrometry detection. Influences of oldenlandia diffusa on the activities of five CYP450 subtypes in rats were evaluated by five specific probe drugs (phenacetin for CYP1A2, omeprazole for CYP2C19, tolbutamide for CYP2C9, metoprolol for CYP2D6, and midazolam for CYP3A4) according to the pharmacokinetic parameters changes. No statistically significant difference (P>0.05) in pharmacokinetic behaviors can be observed in the five probe drugs. There is a potential guidance on clinical drug combination with Oldenlandia diffusa. Oldenlandia diffusa in compound preparation showed well security.

Pharmacokinetics and Pharmacodynamics of Oral Methotrexate and Mercaptopurine in Children With Lower Risk Acute Lymphoblastic Leukemia: A Joint Children’s Cancer Group and Pediatric Oncology Branch Study

Blood ◽  
1998 ◽  
Vol 92 (10) ◽  
pp. 3569-3577 ◽  
Author(s):  
Frank M. Balis ◽  
John S. Holcenberg ◽  
David G. Poplack ◽  
Jeffrey Ge ◽  
Harland N. Sather ◽  
...  
Keyword(s):  
Acute Lymphoblastic Leukemia ◽  
Lower Risk ◽  
Lymphoblastic Leukemia ◽  
Plasma Concentrations ◽  
Pharmacokinetic Parameters ◽  
Cox Regression Analysis ◽  
Oral Methotrexate ◽  
Drug Concentrations ◽  
Significant Difference ◽  
Thioguanine Nucleotide

Abstract We prospectively assessed the pharmacokinetics of methotrexate, mercaptopurine, and erythrocyte thioguanine nucleotide levels in a homogenous population of children with lower risk acute lymphoblastic leukemia and correlated pharmacokinetic parameters with disease outcome. The maintenance therapy regimen included daily oral mercaptopurine (75 mg/m2) and weekly oral methotrexate (20 mg/m2). One hundred ninety-one methotrexate doses and 190 mercaptopurine doses were monitored in 89 patients. Plasma drug concentrations of both agents were highly variable. The area under the plasma concentration-time curve (AUC) of methotrexate ranged from 0.63 to 12 μmol•h/L, and the AUC of mercaptopurine ranged from 0.11 to 8 μmol•h/L. Drug dose, patient age, and duration of therapy did not account for the variability. Methotrexate AUC was significantly higher in girls than boys (P = .007). There was considerable intrapatient variability for both agents. Erythrocyte thioguanine nucleotide levels were also highly variable (range, 0 to 10 pmol/g Hgb) and did not correlate with mercaptopurine dose or AUC. A Cox regression analysis showed that mercaptopurine AUC was a marginally significant (P = .043) predictor of outcome, but a direct comparison of mercaptopurine AUC in the remission and relapsed patient groups failed to show a significant difference. Methotrexate and mercaptopurine plasma concentrations and erythrocyte thioguanine nucleotide levels were highly variable, but measurement of these pharmacokinetic parameters at the start of maintenance will not distinguish patients who are more likely to relapse.

A single-center, open-label clinical study to evaluate pharmacokinetics and pharmacodynamics of pegylated recombinant human granulocyte stimulating factor in pediatric patients with acute lymphoblastic leukemia.

2020 ◽  
Vol 38 (15_suppl) ◽  
pp. e22501-e22501
Author(s):  
Wenyu Yang ◽  
Tianfeng Liu ◽  
Xiaojuan Chen ◽  
Ye Guo ◽  
Ting Li ◽  
...  
Keyword(s):  
Acute Lymphoblastic Leukemia ◽  
Serum Concentration ◽  
Pediatric Patients ◽  
Lymphoblastic Leukemia ◽  
Enzyme Linked Immunosorbent Assay ◽  
Pharmacokinetic Parameters ◽  
Pharmacokinetics And Pharmacodynamics ◽  
Open Label ◽  
Significant Difference ◽  
Stimulating Factor

e22501 Background: The aims of the study were to investigate the pharmacokinetics and pharmacodynamics of pegylated recombinant human granulocyte colony stimulating factor(PEG-rhG-CSF) in pediatric patients with acute lymphoblastic leukemia(ALL), and compare the efficacy and safety of PEG-rhG-CSF (brand name:jinyouli) and rhG-CSF. Methods: Pediatric patients with newly diagnosed ALL who planned to use CAM (cyclophosphamide, cytarabine, 6-mercaptopurine) for chemotherapy were assigned to PEG-rhG-CSF group or rhG-CSF group. In the PEG-rhG-CSF group, PEG-rhG-CSF (100ug/kg) was injected subcutaneously once 48 hours after chemotherapy. In the rhG-CSF group, rhG-CSF (150ug/d) was injected subcutaneously daily from 48 hours after chemotherapy until the absolute neutrophil count (ANC) was≥1.0×109/L. The serum concentration of PEG-rhG-CSF was detected by enzyme-linked immunosorbent assay (ELISA). Safety and efficacy of the two groups were evaluated. Results: Between November 2015 to April 2016, 17 pediatric patients were assigned to PEG-rhG-CSF(n = 9) or rhG-CSF(n = 8) groups. The main pharmacokinetic parameters (mean±SD) of PEG-rhG-CSF group were as follows: Cmax was 353.50±136.3 ng/ml, Tmax was 44.00±20.8 h, t1/2 was 14.58± 2.2h. The PEG-rhG-CSF serum concentration and ANC curve were consistent with the mechanism of neutrophil mediated clearance. The average value of ANC nadir in PEG-rhG-CSF group was 0.18 (±0.32)×109/L, and the rhG-CSF group was 0.08 (±0.09)×109/L, there was no significant difference between the two groups ( P = 0.469). Compared with rhG-CSF, the average time of ANC recovery in PEG-rhG-CSF group was earlier (18.33±2.18 vs. 21.50±2.33, P = 0.021). There were no significant differences in the incidence of FN and infection, the duration of grade Ⅳ neutropenia and hospitalization, and the safety of the two groups. Conclusions: PEG-rhG-CSF had favorable efficacy in pediatric patients with ALL receiving chemotherapy, and there was no serious adverse event. Compared with rhG-CSF, PEG-rhG-CSF needed only once in each chemotherapy cycle, which is more suitable for pediatric patients. Clinical trial information: NCT02953730.

Pharmacokinetics and Pharmacodynamics of Oral Methotrexate and Mercaptopurine in Children With Lower Risk Acute Lymphoblastic Leukemia: A Joint Children’s Cancer Group and Pediatric Oncology Branch Study

Blood ◽  
1998 ◽  
Vol 92 (10) ◽  
pp. 3569-3577 ◽  
Author(s):  
Frank M. Balis ◽  
John S. Holcenberg ◽  
David G. Poplack ◽  
Jeffrey Ge ◽  
Harland N. Sather ◽  
...  
Keyword(s):  
Acute Lymphoblastic Leukemia ◽  
Lower Risk ◽  
Lymphoblastic Leukemia ◽  
Plasma Concentrations ◽  
Pharmacokinetic Parameters ◽  
Cox Regression Analysis ◽  
Oral Methotrexate ◽  
Drug Concentrations ◽  
Significant Difference ◽  
Thioguanine Nucleotide

We prospectively assessed the pharmacokinetics of methotrexate, mercaptopurine, and erythrocyte thioguanine nucleotide levels in a homogenous population of children with lower risk acute lymphoblastic leukemia and correlated pharmacokinetic parameters with disease outcome. The maintenance therapy regimen included daily oral mercaptopurine (75 mg/m2) and weekly oral methotrexate (20 mg/m2). One hundred ninety-one methotrexate doses and 190 mercaptopurine doses were monitored in 89 patients. Plasma drug concentrations of both agents were highly variable. The area under the plasma concentration-time curve (AUC) of methotrexate ranged from 0.63 to 12 μmol•h/L, and the AUC of mercaptopurine ranged from 0.11 to 8 μmol•h/L. Drug dose, patient age, and duration of therapy did not account for the variability. Methotrexate AUC was significantly higher in girls than boys (P = .007). There was considerable intrapatient variability for both agents. Erythrocyte thioguanine nucleotide levels were also highly variable (range, 0 to 10 pmol/g Hgb) and did not correlate with mercaptopurine dose or AUC. A Cox regression analysis showed that mercaptopurine AUC was a marginally significant (P = .043) predictor of outcome, but a direct comparison of mercaptopurine AUC in the remission and relapsed patient groups failed to show a significant difference. Methotrexate and mercaptopurine plasma concentrations and erythrocyte thioguanine nucleotide levels were highly variable, but measurement of these pharmacokinetic parameters at the start of maintenance will not distinguish patients who are more likely to relapse.

Liquid Chromatography-Tandem Mass Spectrometry Method for Ticagrelor and its Active Metabolite Determination in Human Plasma: Application to a Pharmacokinetic Study

2020 ◽  
Vol 16 (5) ◽  
pp. 602-608
Author(s):  
Niloufar Marsousi ◽  
Serge Rudaz ◽  
Jules A. Desmeules ◽  
Youssef Daali
Keyword(s):  
Clinical Trial ◽  
Formic Acid ◽  
Human Plasma ◽  
Active Metabolite ◽  
Pharmacokinetic Parameters ◽  
Pharmacokinetic Studies ◽  
Healthy Male ◽  
Coronary Syndrome ◽  
Healthy Male Volunteers ◽  
Male Volunteers

Background: Ticagrelor is a highly recommended new antiplatelet agent for the treatment of patients with acute coronary syndrome at moderate or high ischemic risk. There is a real need for rapid and accurate analytical methods for ticagrelor determination in biological fluids for pharmacokinetic studies. In this study, a sensitive and specific LC-MS method was developed and validated for quantification of ticagrelor and its Active Metabolite (AM) in human plasma over expected clinical concentrations. Methods: Samples were handled by Liquid-Liquid Extraction (LLE). A linear gradient was applied with a mobile phase composed of formic acid 0.1% and acetonitrile with 0.1% of formic acid using a C18 reversed-phase column. MS spectra were obtained by electrospray ionization in negative mode and optimized at 521.4→360.9 m/z, 477.2→361.2 m/z and 528.1→367.9 m/z transitions for ticagrelor, AM and ticagrelor-d7, respectively. Results: This method allowed rapid elution, in less than 4 minutes, and quantification of concentrations as low as 2 ng/mL for ticagrelor and 1 ng/mL for AM using only 100 μL of human plasma. LLE using hexane/ethyl acetate (50/50) was an optimal compromise in terms of extraction recovery and endogenous compounds interference. Trueness values of 87.8% and 89.5% and precisions of 84.1% and 93.8% were obtained for ticagrelor and AM, respectively. Finally, the usefulness of the method was assessed in a clinical trial where a single 180 mg ticagrelor was orally administered to healthy male volunteers. Pharmacokinetic parameters of ticagrelor and its active metabolite were successfully determined. Conclusion: A sensitive and specific quantification LC-MS-MS method was developed and validated for ticagrelor and its active metabolite determination in human plasma. The method was successfully applied to a clinical trial where a single ticagrelor 180 mg dose was orally administered to healthy male volunteers. The described method allows quantification of concentrations as low as 2 ng/mL of ticagrelor and 1 ng/mL of the metabolite using only 100 μL of plasma.

Association of CYP2D6*10 (c. 100 C>T) Genotype with Z-END Concentration in Patients with Breast Cancer Receiving Tamoxifen Therapy in Indonesian Population

2019 ◽  
Vol 19 (8) ◽  
pp. 1198-1206 ◽  
Author(s):  
Yenny ◽  
Sonar S. Panigoro ◽  
Denni J. Purwanto ◽  
Adi Hidayat ◽  
Melva Louisa ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Steady State ◽  
Ultra Performance Liquid Chromatography ◽  
Cross Sectional Study ◽  
Threshold Concentration ◽  
Breast Cancer Patients ◽  
Cross Sectional ◽  
Significant Difference ◽  
Pcr Rflp ◽  
Liquid Chromatography Tandem Mass

Background: Tamoxifen (TAM) is a frequently used hormonal prodrug for patients with breast cancer that needs to be activated by cytochrome P450 2D6 (CYP2D6) into Zusammen-endoxifen (Z-END). Objective: The purpose of the study was to determine the association between CYP2D6*10 (c.100C>T) genotype and attainment of the plasma steady-state Z-END minimal threshold concentration (MTC) in Indonesian women with breast cancer. Methods: A cross-sectional study was performed in 125 ambulatory patients with breast cancer consuming TAM at 20 mg/day for at least 4 months. The frequency distribution of CYP2D6*10 (c.100C>T) genotypes (C/C: wild type; C/T: heterozygous mutant; T/T: homozygous mutant) was detected using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), the results of which were subsequently confirmed by sequencing. The genotypes were categorized into plasma Z- END concentrations of <5.9 ng/mL and ≥5.9 ng/mL, which were measured using ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). Results: Percentages of C/C, CT, and T/T genotypes were 22.4%, 29.6%, and 48.8%, respectively. Median (25-75%) Z-END concentrations in C/C, C/T, and T/T genotypes were 9.58 (0.7-6.0), 9.86 (0.7-26.6), and 3.76 (0.9-26.6) ng/mL, respectively. Statistical analysis showed a significant difference in median Z-END concentration between patients with T/T genotype and those with C/C or C/T genotypes (p<0.001). There was a significant association between CYP2D6*10 (c.100C>T) genotypes and attainment of plasma steady-state Z-END MTC (p<0.001). Conclusion: There was a significant association between CYP2D6*10 (c.100C>T) and attainment of plasma steady-state Z-END MTC in Indonesian breast cancer patients receiving TAM at a dose of 20 mg/day.

scholarly journals Increased Levels of Adipocyte and Epidermal Fatty Acid-Binding Proteins in Acute Lymphoblastic Leukemia Survivors

2021 ◽  
Vol 10 (8) ◽  
pp. 1567
Author(s):  
Katarzyna Konończuk ◽  
Eryk Latoch ◽  
Beata Żelazowska-Rutkowska ◽  
Maryna Krawczuk-Rybak ◽  
Katarzyna Muszyńska-Rosłan
Keyword(s):  
Metabolic Syndrome ◽  
Fatty Acid ◽  
Acute Lymphoblastic Leukemia ◽  
Binding Proteins ◽  
Lymphoblastic Leukemia ◽  
Fatty Acid Binding Proteins ◽  
Fatty Acid Binding ◽  
The Metabolic Syndrome ◽  
Increased Risk ◽  
Significant Difference

Childhood cancer survivors are highly exposed to the development of side effects after many years of cessation of anticancer treatment, including altered lipid metabolism that may result in an increased risk of overweight and metabolic syndrome. Adipocyte (A-FABP) and epidermal (E-FABP) fatty acid-binding proteins are expressed in adipocytes and are assumed to play an important role in the development of lipid disturbances leading to the onset of metabolic syndrome. The aim of this study was to investigate the association between serum A-FABP and E-FABP levels, overweight, and components of the metabolic syndrome in acute lymphoblastic leukemia survivors. Sixty-two acute lymphoblastic leukemia (ALL) survivors (34 females) were included in the study. The mean age at the time of the study was 12.41 ± 4.98 years (range 4.71–23.43). Serum levels of A-FABP and E-FABP were analyzed using a commercially available ELISA kit. The ALL survivors presented statistically higher A-FABP levels in comparison with the healthy controls (25.57 ± 14.46 vs. 15.13 ± 7.61 ng/mL, p < 0.001). The subjects with body mass index (BMI) above the normal range (18 overweight, 10 obese) had a greater level of A-FABP compared to the ALL group with normal BMI (32.02 ± 17.10 vs. 20.33 ± 9.24 ng/mL, p = 0.006). Of all participants, 53.23% had at least one risk factor of metabolic syndrome; in this group, only the A-FABP level showed a statistically significant difference compared to the healthy control group (30.63 ± 15.91 vs. 15.13 ± 7.61 ng/mL, p < 0.001). The subjects with two or more metabolic risk factors (16.13%) presented higher levels of both A-FABP (33.62 ± 17.16 vs. 15.13 ± 7.61 ng/mL, p = 0.001) and E-FABP (13.37 ± 3.62 vs. 10.12 ± 3.21 ng/mL, p = 0.021) compared to the controls. Univariable regression models showed significant associations between BMI and systolic blood pressure with the A-FABP level (coeff. 1.02 and 13.74, respectively; p < 0.05). In contrast, the E-FABP level was only affected by BMI (coeff. 0.48; p < 0.01). The findings reported herein suggest that the increased levels of A-FABP and E-FABP may be involved in the pathogenesis of overweight and the onset of metabolic syndrome in acute lymphoblastic leukemia. However, further longitudinal, prospective studies of fatty acid-binding proteins and their potential role in the pathogenesis of obesity and metabolic syndrome in ALL survivors remain to be performed.

scholarly journals Transitional Cell Carcinomas of the Urinary Tract in a Colony of Beagle Dogs

1989 ◽  
Vol 26 (6) ◽  
pp. 455-461 ◽  
Author(s):  
K. J. Nikula ◽  
S. A. Benjamin ◽  
G. M. Angleton ◽  
A. C. Lee
Keyword(s):  
Urinary Tract ◽  
Transitional Cell ◽  
Clinical Signs ◽  
Conclusive Evidence ◽  
Whole Body ◽  
Beagle Dogs ◽  
Long Term Effects ◽  
Significant Difference ◽  
Microscopic Features

Gross and light microscopic features of transitional cell carcinomas (TCC) of the urinary tract were examined in Beagle dogs used for the study of the long-term effects of low-dose, whole-body, 60Co gamma radiation. Thirty-eight cases of TCC occurred among 990 dogs that were from 0 to 14 years of age. There was no conclusive evidence of a radiation effect. The 38 TCC were equally divided between male and female dogs, but there was a significant difference in the sex distribution of urethra-origin TCC. Eleven males had a primary urethral TCC compared to only two females. There was no significant difference between the urethra-origin and bladder-origin TCCs in the number of tumors that caused clinical signs, metastasized, or that contributed to the death of the dog. All cases of urethral TCC in male dogs occurred in the prostatic urethra. The majority of these cases were not recognized to be neoplasms at gross necropsy, but microscopic examination revealed the TCC. Our findings differ from previous reports stating that TCC occurs more frequently in female than male dogs, and they especially differ from reports claiming that urethra-origin TCC is predominately a disease of female dogs.

Sign in / Sign up

Export Citation Format

Share Document