Adenocarcinoma constitutes around 0.5 to 2% of all neoplastic lesions of the urinary bladder, out of which, the mucinous variant is seen on rare occasions. Intestinal metaplasia resulting from nephrolithiasis, chronic inflammation and hydronephrosis could be the precursor lesion. Bladder exstrophy and remnants of the urachus are considered as other possible risk factors. The tumour prefers patients who are over 50 years. Hematuria, difficult voiding and suprapubic pain are the most common presenting symptoms. The tumour has a very bad prognosis and is poorly responsive to chemo and radiotherapy and hence surgery is the treatment of choice. Hence early diagnosis is of paramount importance. While managing adenocarcinoma of the bladder, it is important to rule out any possibility of a metastatic lesion that could have come from other organs where mucinous adenocarcinoma is more common.
Imatinib, a selective tyrosine kinase inhibitor, is the first line treatment against chronic myelogenous leukaemia (CML) and gastrointestinal stromal tumors (GIST). Several fatal cases have been associated with imatinib hepatotoxicity. Acetaminophen, an over-the-counter analgesic, anti-pyretic drug, which can cause hepatotoxicity, is commonly used in cancer pain management. We assessed renal and hepatic toxicity after imatinib and acetaminophen co-administration in a preclinical model. Four groups of male ICR mice (30-35 g) were fasted overnight and administered either saline solution orally (baseline control), imatinib 100 mg/kg orally (control), acetaminophen 700 mg/kg intraperitoneally (positive control) or co-administered imatinib 100 mg/kg orally and acetaminophen 700 mg/kg intraperitoneally (study group), and sacrificed at 15 min, 30 min, 1 h, 2 h, 4 h and 6 h post-administration (n = 4 per time point). The liver and kidneys were harvested for histopathology assessment. The liver showed reversible cell damage like feathery degeneration, microvesicular fatty change, sinusoidal congestion and pyknosis, when imatinib or acetaminophen were administered separately. The damage increased gradually with time, peaked at 2 h but resolved by 4 h. When both drugs were administered concurrently, the liver showed irreversible damage (cytolysis, karyolysis and karyorrhexis) which did not resolve by 6 h. Very minor renal changes were observed. Acetaminophen and imatinib co-administration increased hepatoxicity which become irreversible, probably due to shared P450 biotransformation pathways and transporters in the liver.
PURPOSE: Imatinib is an efficacious drug against chronic myeloid leukemia (CML) and gastrointestinal stromal tumor (GIST) due to selective inhibition of c-KIT and BCR-ABL kinases. It presents almost complete bioavailability, is eliminated via P450-mediated metabolism and is well tolerated. However, a few severe drug-drug interactions have been reported in cancer patients taking acetaminophen.
MATERIALS AND METHODS: Male ICR mice were given 100 mg/kg single dose of imatinib orally or imatinib 100 mg/kg (orally) coadministered with acetaminophen intraperitoneally (700 mg/kg). Mice were euthanized at predetermined time points, blood samples collected, and imatinib plasma concentration measured by HPLC.
RESULTS: Imatinib AUC(0-12) was 27.04 +/- 0.38 mg.h/ml, C(max) was 7.21 +/- 0.99 mg/ml and elimination half-life was 2.3 hours. Acetaminophen affected the imatinib disposition profile: AUC(0-12) and C(max) decreased 56% and 59%, respectively and a longer half-life was observed (5.6 hours).
CONCLUSIONS: The study shows a pharmacokinetic interaction between acetaminophen and imatinib which may render further human studies necessary if both drugs are administered concurrently to cancer patients.
The present study was undertaken to develop a rat model for monitoring the early development of breast cancer. Twelve female rats were divided into two groups of six rats that were either treated with N-methyl-N-nitrosourea to induce breast cancer or with bacterial lipopolysaccharide to induce inflammation. Serum samples taken from the rats prior to the treatment were used as controls. By the 14th week, presence of the tumor was detectable by contrast enhanced magnetic resonance imaging and confirmed by histopathology. When the serum proteins of the rats were examined by 2-dimensional electrophoresis (2-DE), no difference could be detected in the profiles of all proteins before and 18 weeks after administration of N-methyl-N-nitrosourea. However, higher expression of alpha-1B glycoprotein was detectable by 2-DE in serum samples of rats at the 18th week post-treatment with lipopolysaccharide.