Low serum concentrations of bevacizumab and nivolumab owing to excessive urinary loss in patients with proteinuria: a case series.

PURPOSE: Proteinuria can cause interindividual variability in the pharmacokinetics of therapeutic antibodies and may affect therapeutic efficacy. Here, we measured the serum and urinary concentrations of bevacizumab (BV) and nivolumab (NIVO) in patients with proteinuria and reported a case series of these patients. METHODS: Thirty-two cancer patients who received BV every 3 weeks or NIVO every 2 weeks between November 2020 and September 2021 at Kyoto University Hospital were enrolled in this study. The serum and urinary concentrations of BV and NIVO were measured using liquid chromatography-tandem mass spectrometry. RESULTS: We divided the BV-treated patients and the NIVO-treated patients into two groups based on the urine protein-creatinine ratio (UPCR): UPCR 1 g/g or higher (BV, n = 9; NIVO, n = 3) and UPCR less than 1 g/g (BV, n = 14; NIVO, n = 6). Serum concentrations of the therapeutic antibodies adjusted by their doses were significantly lower in both BV- and NIVO-treated patients with UPCR 1 g/g or higher compared to those with less than 1 g/g. In patients with UPCR 1 g/g or higher, urinary concentrations of the therapeutic antibodies adjusted by their serum concentrations and urinary creatinine concentrations tended to increase. CONCLUSION: This case-series study suggests a possibility of reduction in serum concentrations of BV and NIVO in patients with proteinuria by urinary excretion of these drugs.

Proteinuria frequency and subsequent renal dysfunction in bevacizumab-treated patients: a single center, retrospective, observational study.

BACKGROUND: Proteinuria is a common adverse event observed during treatment with antivascular endothelial growth factor (VEGF) antibodies. Proteinuria is a risk factor for renal dysfunction and cardiovascular complications in patients with chronic kidney disease. However, the association between anti-VEGF antibody-induced proteinuria and renal dysfunction or cardiovascular complications remains unclear. METHODS: This retrospective, observational study included patients with cancer that were treated with bevacizumab (BV) at Kyoto University Hospital (Kyoto, Japan) between January 2006 and March 2018. Adverse event rates were compared between patients who developed qualitative ≥ 2 + proteinuria and those who developed < 1 + proteinuria. Adverse events were defined as renal dysfunction (i.e., ≥ 57% decrease in the eGFR, compared to the rate at the initial treatment) and hospitalization due to BV-associated cardiovascular complications and other adverse events. RESULTS: In total, 734 patients were included in this analysis. Renal dysfunction was more common in patients with ≥ 2 + proteinuria than in those with < 1 + proteinuria (13/199, 6.5% vs. 12/535, 2.3%). Seven of these 13 patients with ≥ 2 + proteinuria had transient reversible renal dysfunction. Only four (2.0%) patients had BV-associated renal dysfunction. Of the 734 patients, six patients, 16 patients, and 13 patients were hospitalized because of the adverse events of cardiovascular complications, thromboembolisms, and cerebrovascular complications, respectively. No relationship was observed between these adverse events and proteinuria. CONCLUSION: BV treatment-induced proteinuria was not associated with renal dysfunction or other adverse events. Continuing BV with caution is a possible treatment option, even after proteinuria develops, in patients with cancer and a limited prognosis.

Removal rate of 5-fluorouracil and its metabolites in patients on hemodialysis: a report of two cases of colorectal cancer patients with end-stage renal failure.

PURPOSE: Hyperammonemia is a serious adverse effect of 5-fluorouracil (5FU) administration. Hemodialysis can be used for its management, but detailed data on the concentrations and removal rate of 5FU and its metabolites during hemodialysis remain unclear. Here, we present two cases of hemodialysis patients with end-stage renal disease who received concurrent 5FU infusion. METHODS: Blood samples were collected from the hemodialysis circuit before and after the dialyzer during day 2 hemodialysis sessions, and from the internal shunt just before and after day 4 hemodialysis sessions. The serum levels of 5FU and its metabolites-α-fluoro-ß-alanine (FBAL) and monofluoroacetate (FA)-were measured using liquid chromatography-tandem mass spectrometry. RESULTS: Seven sets of blood samples were collected for case 1; the removal rates (mean ± standard deviation) of 5FU and FBAL by the dialyzer were 81.2 ± 23.2% and 96.1 ± 8.6%, respectively (p < 0.001). Three sets of blood samples were collected for case 2; the removal rates of 5FU and FBAL were 81.7 ± 3.9% and 94.8 ± 2.7%, respectively (p = 0.03). Twenty-seven sets of blood samples were collected for case 1; reductions in blood FBAL and FA levels were 49.3 ± 8.8% (p < 0.001) and 64.2 ± 30.3% (p = 0.04), respectively. Bayesian estimation yielded similar results. Three sets of blood samples were collected for case 2; reductions in the blood FBAL and FA levels were 49.9 ± 6.9% and 50.6 ± 33.0%, respectively. CONCLUSION: In this study, 5FU and its metabolite FBAL were directly removed from the blood by approximately 90% during hemodialysis, and the blood levels of FBAL and FA were reduced by approximately 50% with a single hemodialysis session.

Medical care costs according to the stage and subtype of breast cancer in a municipal setting: a case study of Hachioji City, Japan.

BACKGROUND: It is important to assess whether the early detection of breast cancer affects medical care costs. However, research remains scant on the actual medical care costs associated with breast cancer treatment in Japan. This study aimed to determine the medical care costs of breast cancer treatment based on its stage using national health insurance claims data. METHODS: This was an observational study including patients with breast cancer who had undergone breast cancer treatment, as defined by the disease name and related treatment codes. Between August 2013 and June 2016, patients who underwent surgical treatment without axillary lymph node dissection and other radical treatment were classified as the curable group, while those who underwent palliative treatment were classified as the non-curable group. Patients were further stratified by subtype. The total and treatment-specific medical care costs for the five years were calculated using the national health insurance claims data of Hachioji City between August 2013 and May 2021. RESULTS: The mean total medical care costs for the curable and non-curable groups for the 5 years were JPY 3958 thousand (standard deviation 2664) and JPY 8289 thousand (8482), respectively. The mean medical care costs for specific breast cancer treatment for the curable and non-curable groups were JPY 1142 (728) thousand and JPY 3651 thousand (5337), respectively. Further, human epidermal growth factor receptor 2 + , Hormone + patients had the highest mean cost over the 5 years. CONCLUSIONS: The results suggest that the early detection of breast cancer may reduce medical care costs at the patient level.

Association between homologous recombination gene variants and efficacy of oxaliplatin-based chemotherapy in advanced pancreatic cancer: prospective multicenter observational study.

Next-generation sequencing (NGS)-based gene profiling can identify patients with pancreatic cancer with homologous recombinant repair gene pathogenic variants (HRRv). Several retrospective studies have reported a positive association between HRRv and the efficacy of platinum-based chemotherapy. However, this association remains to be validated in a prospective study. This multicenter, prospective, observational study included patients with histologically confirmed unresectable or recurrent pancreatic cancer who required systemic chemotherapy. Patients who were oxaliplatin-naïve patients were eligible. The HRRv status was measured using a College of American Pathologists-accredited NGS panel. One-year overall survival rate (1yr-OS%) was calculated after initiation of oxaliplatin-based chemotherapy and was set as the primary endpoint. Forty patients were enrolled between August 2018 and March 2020. The NGS success rate was 95% (38/40). HRRv was detected in 11 patients (27.5%). Oxaliplatin-based chemotherapy was administered to 9 of 11 patients with HRRv (81.8%) and 15 of 29 patients with non-HRRv (51.7%). The 1yr-OS% after initiation of oxaliplatin-based chemotherapy was 44.4% [95% confidence interval (CI) 13.7-71.9] and 57.1% (95% CI 28.4-78.0) in HRRv-positive and -negative cohorts, respectively. These data suggested that HRRv status alone could not be a potential predictive marker of oxaliplatin-based chemotherapy in patients with advanced pancreatic cancer. These results were in line with the results of a recent phase II study reporting the limited efficacy of poly(adenosine diphosphate-ribose) polymerase inhibitor in patients with pancreatic cancer who harbored HRRv other than BRCA. Future studies investigating patients with biallelic HRRv in the first-line setting are warranted.Trial registration UMIN000033655.

Effect of Severe Renal Dysfunction on the Plasma Levels of DNA-Reactive Platinum after Oxaliplatin Administration.

Higher amounts of circulating ultrafilterable platinum (fPt) are found in patients with renal dysfunction receiving a constant dose of oxaliplatin. However, the increased systemic fPt levels do not increase oxaliplatin-induced toxicities. We hypothesized that renal dysfunction has minimal effect on the elimination rate of reactive fPt, and that the DNA-binding capacity is one of the properties of reactive Pt species. This study aimed to quantify DNA-reactive fPt in plasma and to evaluate the impact of severe renal dysfunction on its pharmacokinetics. The pharmacokinetics of oxaliplatin was assessed in rats with bilateral nephrectomy (BNx) and in a hemodialysis patient who received mFOLFOX7 therapy for advanced metastatic gastric cancer. The platinum concentrations were determined using inductively coupled plasma-mass spectrometry. The amount of DNA-reactive fPt in the plasma was evaluated by the reaction between plasma and calf thymus DNA. Compared to the sham group in rats, the BNx group had significantly higher plasma total fPt concentrations at 24 h after drug administration. However, there was no significant difference in the plasma levels of DNA-reactive fPt between the two groups. In a hemodialysis patient, the plasma levels of total fPt decreased to 35.9 and 7.3% at 2 and 14 d after treatment, respectively. The plasma level of DNA-reactive fPt also decreased to 1.9 and 0.6%, respectively, on these days. This study showed that severe renal dysfunction has a limited effect on the plasma levels of DNA-reactive fPt after oxaliplatin administration.

Use of Cabozantinib to Treat MET -amplified Pediatric Colorectal Cancer.

Pediatric colorectal cancer (CRC) is extremely rare, with little information about genetic profiles compared with adult CRC. Here, a 13-year-old male with advanced CRC underwent cancer gene panel testing, which detected 4 genetic abnormalities ( MET amplification in addition to TP53 , SMAD4 , and CTNNA1 mutations) that might be associated with a poor prognosis. Based on high-level MET amplification, he received a multikinase inhibitor, cabozantinib, after failure of first-line and second-line chemotherapy, resulting in transient disease stabilization. Tailored targeted therapy based on molecular profiling can be an effective treatment strategy for rare cancers such as pediatric CRC.

Decision making for anti-VEGF inhibitor continuation: dip stick? or urine protein/creatinine ratio? (VERSiON UP study).

BACKGROUND: Monitoring proteinuria is important for the management of patients with cancer treated with anti-vascular endothelial growth factor (VEGF) or anti-VEGF receptor (VEGFR) inhibitors (VEGF/Ri). Here we investigated the difference between the urine protein/creatinine ratio (UPCR) and a qualitative value test (QV) on the decision making of treatment continuation and the usefulness of UPCR testing in patients with gastrointestinal cancer treated with anti-VEGF/Ri. METHODS: From January 2017 to December 2018, a survey was conducted based on the medical records of patients with gastrointestinal cancer with a QV of ≥2+ during the use of anti-VEGF/Ri at seven Japanese institutions participating in the Onco-nephrology Consortium. The primary endpoint was the ratio of the worst UPCR < 2.0 (low UPCR) in cases with a QV2+ at the point of the first proteinuria onset. The secondary endpoints were a comparison of low UPCR and worst UPCR ≥2.0 (high UPCR), the concordance rate between UPCR and QV in the Common Terminology Criteria for Adverse Events (CTCAE) grading, and the differences in the decision making for anti-VEGF/Ri continuation. RESULTS: Among the 71 patients enrolled, the proportion of low UPCR in onset QV2+ (n = 53) was 66% (n = 35). In a comparison between low (n = 36) and high UPCR cases (n = 24), body weight (P = 0.036), onset QV status (P = 0.0134), and worst QV status (P < 0.0001) were significantly associated with UPCR levels. The concordance rate for CTCAE Grade 2 of both the QV and UPCR was 83%. Regarding the judgment of anti-VEGF/Ri continuation, treatment was continued in 42.4% of cases when the QV became 3+, whereas only 25% continued treatment when the UPCR value became high. CONCLUSION: Urine dipstick test results may overestimate proteinuria, and the UPCR result tended to be more critical than the QV when deciding the treatment policy. TRIAL REGISTRATION: This study is a multiple institutional retrospectively registered observational trial. CLINICAL TRIAL NUMBER: University Hospital Medical Information Network (UMIN) Clinical Trials Registry (protocol ID UMIN000042545 ).

Indolent feature of Helicobacter pylori-uninfected intramucosal signet ring cell carcinomas with CDH1 mutations.

BACKGROUND: In Helicobacter pylori (Hp)-uninfected individuals, diffuse-type gastric cancer (DGC) was reported as the most common type of cancer. However, the carcinogenic mechanism of Hp-uninfected sporadic DGC is largely unknown. METHODS: We performed whole-exome sequencing of Hp-uninfected DGCs and Hp-uninfected normal gastric mucosa. For advanced DGCs, external datasets were also analyzed. RESULTS: Eighteen patients (aged 29-78 years) with DGCs and nine normal subjects (28-77 years) were examined. The mutation burden in intramucosal DGCs (10-66 mutations per exome) from individuals aged 29-73 years was not very different from that in the normal gastric glands, which showed a constant mutation accumulation rate (0.33 mutations/exome/year). Unbiased dN/dS analysis showed that CDH1 somatic mutation was a driver mutation for intramucosal DGC. CDH1 mutation was more frequent in intramucosal DGCs (67%) than in advanced DGCs (27%). In contrast, TP53 mutation was more frequent in advanced DGCs (52%) than in intramucosal DGCs (0%). This discrepancy in mutations suggests that CDH1-mutated intramucosal DGCs make a relatively small contribution to advanced DGC formation. Among the 16 intramucosal DGCs (median size, 6.5 mm), 15 DGCs were pure signet ring cell carcinoma (SRCC) with reduced E-cadherin expression and a low proliferative capacity (median Ki-67 index, 2.4%). Five SRCCs reviewed endoscopically over 2-5 years showed no progression. CONCLUSIONS: Impaired E-cadherin function due to CDH1 mutation was considered as an early carcinogenic event of Hp-uninfected intramucosal SRCC. Genetic and clinical analyses suggest that Hp-uninfected intramucosal SRCCs may be less likely to develop into advanced DGCs.

Comprehensive genomic profiling for patients with chemotherapy-naïve advanced cancer.

Comprehensive genomic profiling (CGP) testing by next-generation sequencing has been introduced into clinical practice as part of precision cancer medicine to select effective targeted therapies. However, whether CGP testing at the time of first-line chemotherapy could be clinically useful is not clear. We conducted this single-center, prospective, observational study to investigate the feasibility of CGP testing for chemotherapy-naïve patients with stage III/IV gastrointestinal cancer, rare cancer, and cancer of unknown primary, using the FoundationOne® companion diagnostic (F1CDx) assay. The primary outcome was the detection rate of at least one actionable/druggable cancer genomic alteration. Actionable/druggable cancer genomic alterations were determined by the F1CDx report. An institutional molecular tumor board determined the molecular-based recommended therapies. A total of 197 patients were enrolled from October 2018 to June 2019. CGP success rate was 76.6% (151 of 197 patients), and median turnaround time was 19 days (range: 10-329 days). Actionable and druggable cancer genomic alterations were reported in 145 (73.6%) and 124 (62.9%) patients, respectively. The highest detection rate of druggable genomic alterations in gastrointestinal cancers was 80% in colorectal cancer (48 of 60 patients). Molecular-based recommended therapies were determined in 46 patients (23.4%). CGP testing would be a useful tool for the identification of a potentially effective first-line chemotherapy.

Prospective evaluation and refinement of an S-1 dosage formula based on renal function for clinical application.

In patients with impaired renal function, S-1-related toxicities increase due to higher exposure of 5-fluorouracil (5-FU). Our previous pharmacokinetic study in 16 cancer patients with various renal functions developed an S-1 dosage formula based on individual creatinine clearance (CLcr) and body surface area (BSA). To evaluate and refine the formula, this prospective study was conducted. Thirty-three patients with various renal functions received S-1 for 4 weeks at doses determined by the nomogram derived from the previously developed formula. A series of blood samples were collected after the first dose to calculate the area under the concentration-time curve (AUC) of 5-FU. Thirty patients with BSA of 1.14-1.84 m2 and CLcr of 23.8-96.4 mL/min were assessable for pharmacokinetics. The observed daily AUC ranged from 712.6 to 2868.7 ng·h/mL, and 18 patients achieved the target AUC (1447.8 ± 545.4 ng·h/mL). Three patients experienced S-1-related grade 3 adverse events during the first course. In the population pharmacokinetic analysis from the combined data of 46 patients in this study and the previous study, sex was identified as a statistically significant covariate for 5-FU clearance. Hence, the refined formula includes sex as an additional factor: Recommended daily dose = target AUC × (14.5 + 8.23 × SEX [0 for female and 1 for male] + 0.301 × CLcr) × BSA. Revised nomograms for recommended daily doses derived from the refined formula can be used in clinical practice to achieve the target AUC ensuring efficacy and safety of S-1.

Successful management of hyperammonemia with hemodialysis on day 2 during 5-fluorouracil treatment in a patient with gastric cancer: a case report with 5-fluorouracil metabolite analyses.

PURPOSE: Hyperammonemia is an important adverse event associated with 5-fluorouracil (5FU) from 5FU metabolite accumulation. We present a case of an advanced gastric cancer patient with chronic renal failure, who was treated with 5FU/leucovorin (LV) infusion chemotherapy (2-h infusion of LV and 5FU bolus followed by 46-h 5FU continuous infusion on day 1; repeated every 2 weeks) and developed hyperammonemia, with the aim of exploring an appropriate hemodialysis (HD) schedule to resolve its symptoms. METHODS: The blood concentrations of 5FU and its metabolites, α-fluoro-ß-alanine (FBAL), and monofluoroacetate (FA) of a patient who had hyperammonemia from seven courses of palliative 5FU/LV therapy for gastric cancer were measured by liquid chromatography-mass spectrometry. RESULTS: On the third day of the first cycle, the patient presented with symptomatic hyperammonemia relieved by emergency HD. Thereafter, the 5FU dose was reduced; however, in cycles 2-4, the patient developed symptomatic hyperammonemia and underwent HD on day 3 for hyperammonemia management. In cycles 5-7, the timing of scheduled HD administration was changed from day 3 to day 2, preventing symptomatic hyperammonemia. The maximum ammonia and 5FU metabolite levels were significantly lower in cycles 5-7 than in cycles 2-4 (NH3 75 ± 38 vs 303 ± 119 µg/dL, FBAL 13.7 ± 2.5 vs 19.7 ± 2.0 µg/mL, FA 204.0 ± 91.6 vs 395.9 ± 12.6 ng/mL, mean ± standard deviation, all p < 0.05). After seven cycles, partial response was confirmed. CONCLUSION: HD on day 2 instead of 3 may prevent hyperammonemia in 5FU/LV therapy.

Chemotherapy for patients with unresectable or metastatic small bowel adenocarcinoma: a systematic review.

BACKGROUND: There is no standard chemotherapy available for unresectable or metastatic small bowel adenocarcinoma (SBA) because of its rarity. This systematic review aims to assess the efficacy and safety of chemotherapy for patients with unresectable or metastatic SBA. METHODS: In accordance with the PRISMA statements, literature search was conducted using PubMed, Scopus, and the Cochrane Central Register of Controlled Trials. The included studies were prospective randomized, nonrandomized, or observational studies. Risk of bias was assessed the ROBINS-I tool. RESULTS: Seven prospective single-arm Phase II studies were included in this review. Six of them were assessed as having a moderate risk of bias and one as having a serious risk of bias. A meta-analysis was not performed, because the studies were single-arm. Systemic chemotherapy based on fluoropyrimidine regimens achieved favorable outcomes with acceptable adverse effects as a first therapy; however, the regimens differed in each study. The object response rate was 18-50%, and the disease control rate was 29-87%. With 5-fluorouracil, adriamycin, and mitomycin-C regimen, one treatment-related death occurred. A second line of therapy including chemotherapy with nab-paclitaxel also showed favorable efficacy. The object response rate was 20%, and the disease control rate was 50%. CONCLUSIONS: Systemic chemotherapy based on fluoropyrimidine regimens was mainly used for unresectable or metastatic SBA. While it may achieve favorable outcomes with acceptable adverse effects, further evidence is needed.

Long-term survival and renal dysfunction in a patient with recurrent colorectal cancer treated with Bevacizumab.

Advances in cancer chemotherapy have increased the opportunities of treating patients with cancer with renal dysfunction. Here we report the case of a 64-year-old woman with recurrent colorectal cancer who was treated with bevacizumab (BEV) combination chemotherapy. Although proteinuria caused by BEV developed early during the treatment and her renal function gradually deteriorated, BEV combination chemotherapy could be continued for 48 cycles over 2.5 years for controlling disease progression without other adverse events such as hypertension, decreased serum albumin level, or edema. After BEV discontinuation, proteinuria gradually improved and further renal function deterioration was not observed. Because the therapeutic options available for metastatic colorectal cancer are limited, balancing the risks and benefits of continuing chemotherapy is important in cases of adverse events.

Genetic analysis of a case of Helicobacter pylori-uninfected intramucosal gastric cancer in a family with hereditary diffuse gastric cancer.

Germline mutations in CDH1, encoding E-cadherin, are known to be the causative mechanism of hereditary diffuse gastric cancer (HDGC). We encountered two cases of gastric cancer in a Japanese family with HDGC. A 28-year-old man (Case 1) died of advanced gastric cancer. His younger sister aged 27 (Case 2) was diagnosed with intramucosal signet ring cell carcinoma (SRCC). Both had identical germline CDH1 mutations, but Case 1 was positive for Helicobacter pylori infection, whereas Case 2 was negative. Case 2 underwent total gastrectomy. Whole-exome sequencing of an intramucosal SRCC in Case 2 revealed seven somatic mutations including one in CDH1. The six non-CDH1 mutations were classified as non-driver mutations. Decreased expression of E-cadherin in intramucosal SRCC was confirmed by immunohistochemistry. Our report demonstrated that CDH1 mutation was the only active driver mutation in Helicobacter pylori-uninfected intramucosal SRCC.

Chemotherapy in cancer patients undergoing haemodialysis: a nationwide study in Japan.

BACKGROUND: Cancer is a major cause of death in patients undergoing haemodialysis. However, information about the actual clinical practice of chemotherapy for patients with cancer undergoing haemodialysis is lacking. We conducted a nationwide survey using questionnaires on the clinical practice of chemotherapy for such patients. PATIENTS AND METHODS: The nationwide survey included patients undergoing haemodialysis who were subsequently diagnosed with cancer in 20 hospitals in Japan from January 2010 to December 2012. We reviewed their clinical data, including cancer at the following primary sites: kidney, colorectum, stomach, lung, liver, bladder, pancreas and breast. The questionnaires consisted of the following subjects: (1) patient characteristics; (2) regimen, dosage and timing of chemotherapy; and (3) clinical outcome. RESULTS: Overall, 675 patients were registered and assessed for main primary cancer site involvement. Of 507 patients with primary site involvement, 74 patients (15%) received chemotherapy (44 as palliative chemotherapy and 30 as perioperative chemotherapy). The most commonly used cytotoxic drugs were fluoropyrimidine (15 patients), platinum (8 patients) and taxane (8 patients), and the dosage and timing of these drugs differed between institutions; however, the dosage of molecular targeted drugs (24 patients) and hormone therapy drugs (15 patients) was consistent. The median survival time of patients receiving palliative chemotherapy was 13.0 months (0.1-60.3 months). Three patients (6.8%) died from treatment-related causes and nine patients (20%) died of causes other than cancer. Of the 30 patients who received perioperative chemotherapy, 6 (20%) died of causes other than cancer within 3 years after the initiation of chemotherapy. CONCLUSION: Among the haemodialysis patients with cancer who received chemotherapy, the rates of mortality from causes other than cancer might be high for both palliative and perioperative chemotherapy. Indications for the use of chemotherapy in patients undergoing haemodialysis should be considered carefully.

Chemotherapy for primary mediastinal yolk sac tumor in a patient undergoing chronic hemodialysis: a case report.

BACKGROUND: The safety and efficacy of chemotherapy for patients undergoing concomitant hemodialysis have not been fully established and optimal doses of anti-cancer drugs and best timing of hemodialysis remains unclear. Although chemosensitive cancers, such as germ cell tumors, treated with chemotherapy should have sufficient dose intensity maintained to achieve the desired effect, many patients with cancer undergoing hemodialysis might be under-treated because the pharmacokinetics of anti-cancer drugs in such patients remains unknown. CASE PRESENTATION: We describe a 31-year-old Japanese man with a mediastinal yolk sac tumor treated with surgery followed by five cycles of chemotherapy containing cisplatin and etoposide while concomitantly undergoing hemodialysis. The doses of these agents used in the first cycle were 50% of the standard dose of cisplatin (10 mg/m2) and 60% of the standard dose of etoposide (60 mg/m2) on days 1 through to 5; the doses were subsequently escalated to 75% with both agents. Hemodialysis was started 1 hour after infusions of these agents. Severe hematological toxicities were observed despite successful treatment. During treatment with concurrent hemodialysis, pharmacokinetic analysis of cisplatin was performed and its relationship with adverse effects was assessed. Compared with patients with normal renal function, the maximum drug concentration was higher, and concentration increased in the interval between hemodialysis and the subsequent cisplatin infusion, resulting in a higher area under the curve despite a reduction in the dose to 75% of the standard regimen. CONCLUSIONS: Because of the altered pharmacokinetics pharmacodynamics status of patients with renal dysfunction undergoing hemodialysis, pharmacokinetics pharmacodynamics analysis is deemed to be helpful for effective and safe management of chemotherapy in patients undergoing hemodialysis.

Accumulation of alpha-fluoro-beta-alanine and fluoro mono acetate in a patient with 5-fluorouracil-associated hyperammonemia.

PURPOSE: High-dose 5-fluorouracil (5-FU) containing chemotherapy occasionally causes hyperammonemia and can be lethal. However, the mechanism of 5FU-associated hyperammonemia has not been known. The aim of this study was to reveal the pharmacokinetics of 5-FU-associated hyperammonemia in a recurrent colorectal cancer patient with end-stage renal disease (ESRD). METHODS: We experienced a case of hyperammonemia during mFOLFOX6 plus bevacizumab therapy for recurrent colorectal cancer. He was a dialyzed patient due to diabetic nephropathy and was registered to prospective blood sampling for pharmacokinetics analysis during chemotherapy. Blood concentrations of 5-FU and its catabolites were determined by inductively coupled plasma-mass spectrometry. RESULTS: The patient developed hyperammonemia encephalopathy 41 h after the initiation of continuous 5-FU infusion (on the third day). Before onset of hyperammonemia encephalopathy, serum alpha-fluoro-beta-alanine (FBAL, 59.2 µg/ml) and fluoro mono acetate (FMA, 905.8 ng/ml) were gradually increased. After hemodialysis for hyperammonemia, FBAL and FMA were collaterally decreased and his symptom was improved. Other intermediate catabolites of 5-FU, dihydrofluorouracil, and alpha-fluoro-beta-ureidopropionic acid were not changed. CONCLUSION: We found increases of serum FBAL and FMA under the condition of hyperammonemia in the patient with ESRD during mFOLFOX6 plus bevacizumab therapy. This research supported the hypothesis that impairment of tricarboxylic acid (TCA) cycle by FMA would cause 5-FU-associated hyperammonemia.