The efficacy and safety of piperacillin-tazobactam for febrile neutropenic patients in Japan

The IDSA guideline for management of febrile neutropenic patients updated in 2010 recommends monotherapy with anti-pseudomonal-lactam agents, including piperacillin-tazobactam (PIPC/TAZ) for high-risk patients. However, clinical studies of PIPC/TAZ are limited in Japanese patients. In this study, we conducted an open-labeled non-randomized prospective trial to examine the efficacy and safety of PIPC/TAZ as an empirical treatment for Japanese patients with febrile neutropenia. Forty-nine febrile episodes in neutropenic patients excluding those undergoing allogeneic stem cell transplantation (high risk 36, low risk 13) were analyzed. The overall response rate was 71%, and no significant differences between the high-risk and the low-risk group were observed (high risk 72%, low risk 69%). Neither PS nor usage of G-CSF affected the response rate. No major side effects were observed in the study. The efficacy and the safety profile of PIPC/TAZ treatment were comparable to those in other previous Western studies. In conclusion, this study suggests PIPC/TAZ is effective and well tolerated as an initial empirical treatment for febrile neutropenic Japanese patients.     

Falsely elevated thyroid hormone levels caused by anti-ruthenium interference in the Elecsys assay resembling the syndrome of inappropriate secretion of thyrotropin

The syndrome of inappropriate secretion of thyrotropin (SITSH) is defined as the inappropriate non-suppression of serum TSH in the presence of elevated free thyroid hormone; TSH-secreting pituitary adenomas and the syndrome of resistance to thyroid hormone are the main etiologies of SITSH. In addition, erroneous thyroid function testing may result in the diagnosis of this syndrome. A 63-year-old woman was referred because of suspected SITSH. Laboratory tests showed a normal TSH (0.52 μIU/L; normal range: 0.5-5.0) measured by sandwich Elecsys, and elevated FT4 (3.8 ng/dL; normal range: 0.9-1.6) and FT3 (7.6 pg/mL; normal range: 2.3-4.0), determined by competitive Elecsys. To exclude possible assay interference, aliquots of the original samples were retested using a different method (ADVIA Centaur), which showed normal FT4 and FT3 levels. Eight hormone levels, other than thyroid function tests measured by competitive or sandwich Elecsys, were higher or lower than levels determined by an alternative analysis. Subsequent examinations, including gel filtration chromatography, suggested interference by substances against ruthenium, which reduced the excitation of ruthenium, and resulted in erroneous results. The frequency of similar cases, where the FT4 was higher than 3.2 ng/dL, in spite of a non-suppressed TSH, was examined; none of 10 such subjects appeared to have method-specific interference. Here, a patient with anti-ruthenium interference, whose initial thyroid function tests were consistent with SITSH, is presented. This type of interference should be considered when thyroid function is measured using the Elecsys technique, although the frequency of such findings is likely very low.     

Esophageal combined carcinomas: Immunohoistochemical and molecular genetic studies

Primary esophageal combined carcinoma is very rare. The authors herein report 2 cases. Case 1 was a combined squamous cell carcinoma and small cell carcinoma, and case 2 was a combined squamous cell carcinoma, adenocarcinoma, and small cell carcinoma. Case 1 was a 67-year-old man with complaints of dysphagia. Endoscopic examination revealed an ulcerated tumor in the middle esophagus, and 6 biopsies were obtained. All 6 biopsies revealed a mixture of squamous cell carcinoma and small cell carcinoma. Both elements were positive for cytokeratin, epithelial membrane antigen, and p53 protein, and had high Ki-67 labeling. The small cell carcinoma element was positive for synaptophysin, CD56, KIT, and platelet-derived growth factor-α (PDGFRA), while the squamous cell carcinoma element was not. Genetically, no mutations of KIT and PDGFRA were recognized. The patient died of systemic carcinomatosis 15 mo after presentation. Case 2 was a 74-year-old man presenting with dysplasia. Endoscopy revealed a polypoid tumor in the distal esophagus. Seven biopsies were taken, and 6 showed a mixture of squamous cell carcinoma, small cell carcinoma, and adenocarcinoma. The 3 elements were positive for cytokeratins, epithelial membrane antigen, and p53 protein, and had high Ki-67 labeling. The adenocarcinoma element was positive for mucins. The small cell carcinoma element was positive for CD56, synaptophysin, KIT, and PDGFRA, but the other elements were not. Mutations of KIT and PDGFRA were not recognized. The patient died of systemic carcinomatosis 7 mo after presentation. These combined carcinomas may arise from enterochromaffin cells or totipotential stem cell in the esophagus or transdifferentiation of one element to another. A review of the literature was performed.     

Collapsin Response Mediator Protein 4 Expression is Associated with Liver Metastasis and Poor Survival in Pancreatic Cancer

Background

Pancreatic cancer is an aggressive malignancy with one of the worst mortality rates of all cancers. Recently, collapsin response mediator proteins (CRMPs) were reported to be associated with proliferation, apoptosis, differentiation, and invasion in several cancers. However, CRMP expression and their role in pancreatic cancer have not been investigated. This study aimed to clarify the clinical significance of CRMPs in pancreatic cancer.

Methods

Expression of crmp genes in 11 pairs of pancreatic cancer and corresponding noncancerous pancreas tissues were examined by real-time RT-PCR. Knockdown of CRMP4 expression using siRNA was examined in pancreatic cancer cell lines to determine whether CRMP4 regulates cell proliferation and invasion in vitro. Furthermore, CRMP4 protein levels in primary tumors of pancreatic cancer (n = 53) were examined by immunohistochemistry and compared with the clinicopathological features of the tumors.

Results

Of all the CRMPs, only CRMP4 was differentially expressed in pancreatic cancer tissues (p = 0.008). CRMP4 knockdown using siRNA reduced cellular invasion, but did not affect proliferation. The expression of CRMP4 was detected immunohistochemically in 34 (64.2 %) of the 53 pancreatic cancer samples, and CRMP4 expression was correlated with severe venous invasion (p = 0.044), stage (p = 0.019), and liver metastasis (p = 0.021). Multivariate analyses suggested that venous invasion and CRMP4 overexpression were prognostic factors for survival.

Conclusions

Our results suggested that CRMP4 is significantly associated with poor prognosis by promoting liver metastasis and can serve as a novel therapeutic target for pancreatic cancer.

     

Paraoxonase-1 activity affects the clopidogrel response in CYP2C19 loss-of-function carriers

Background

The impact of paraoxonase-1 (PON1) activity on the response to clopidogrel may differ in patients treated with drug-eluting stents (DES) in association with CYP2C19 loss-of-function (LOF) polymorphisms.

Methods

This study included 112 Japanese patients receiving clopidogrel (75 mg/day) and aspirin (100 mg/day) who underwent optical coherence tomography (OCT) examination 9 months after DES implantation. The CYP2C19 genotype was analyzed and LOF carriers (*1/*2, *1/*3, *2/*2, *3/*3, *2/*3) were identified. At the 9-month follow-up, platelet reactivity was determined by measuring the P2Y12 reactivity unit (PRU) using a VerifyNow P2Y12 assay, PON1 activity was evaluated and intra-stent thrombus was evaluated by OCT.

Results

Of the 112 Japanese patients, 75 were LOF carriers (67.0%). The patients were divided into tertiles according to the PON1 activity (tertile 1; < 230 U/L, tertile 2; 230–283 U/L, tertile 3; > 283 U/L). In the VerifyNowP2Y12 analysis, tertile 1 had a higher PRU than tertiles 2 and 3 in LOF carriers, and there was no difference among tertiles in non-carriers. The highest incidence of intra-stent thrombus was observed in tertile 1 followed by tertiles 2 and 3 in LOF carriers, whereas there was no such difference in non-carriers. Multivariate analysis revealed that LOF carriers and PON1 activity tertile 1 were independent predictors of intra-stent thrombus in all patients. In LOF carriers, tertile 1 was the only independent predictor for intra-stent thrombus.

Conclusion

Low PON1 activity is associated with a low response to clopidogrel and a high frequency of intra-stent thrombus only in LOF carriers.