Safety and patient-reported outcomes of atezolizumab, carboplatin, and etoposide in extensive-stage small-cell lung cancer (IMpower133): a randomized phase I/III trial.

BACKGROUND: The addition of atezolizumab to carboplatin and etoposide (CP/ET) significantly improved progression-free and overall survival for patients with extensive-stage small-cell lung cancer (ES-SCLC) in the IMpower133 study (NCT02763579). We have evaluated adverse events (AEs) and patient-reported outcomes in IMpower133 to assess the benefit-risk profile of this regimen. PATIENTS AND METHODS: Patients received four 21-day cycles of CP/ET plus intravenous atezolizumab 1200 mg or placebo (induction phase), followed by atezolizumab or placebo (maintenance phase) until progression or loss of benefit. AEs were assessed and patient-reported outcomes were evaluated every 3 weeks during treatment using the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire - Core 30 (QLQ-C30) and QLQ-LC13. RESULTS: Overall, 394 patients were assessable for safety in the induction phase and 318 in the maintenance phase. The frequency of AEs, grade 3-4 AEs, and serious AEs was similar between arms in both phases. Immune-related AEs were more frequent in the atezolizumab arm during both induction (28% versus 17%; leading to atezolizumab/placebo interruption 9% versus 5%, leading to withdrawal 4% versus 0%) and maintenance (26% versus 15%; leading to atezolizumab/placebo interruption, 3% versus 2%, leading to withdrawal 1% versus 1%), most commonly rash (induction 11% versus 9%, maintenance 14% versus 4%), and hypothyroidism (induction 4.0% versus 0%, maintenance 10% versus 1%). Changes in patient-reported treatment-related symptoms commonly associated with quality of life impairment were generally similar during induction and most of the maintenance phase. Patient-reported function and health-related quality of life (HRQoL) improved in both arms after initiating treatment, with more pronounced and persistent HRQoL improvements in the atezolizumab arm. CONCLUSIONS: In patients with ES-SCLC, atezolizumab plus CP/ET has a comparable safety profile to placebo plus CP/ET, and the addition of atezolizumab did not adversely impact patient-reported HRQoL. These data demonstrate the positive benefit-risk profile of first-line atezolizumab plus CP/ET in ES-SCLC and further support this regimen as a new standard of care in this setting. CLINICAL TRIALS NUMBER: NCT02763579.

Final overall survival results of WJTOG3405, a randomized phase III trial comparing gefitinib versus cisplatin with docetaxel as the first-line treatment for patients with stage IIIB/IV or postoperative recurrent EGFR mutation-positive non-small-cell lung cancer.

BACKGROUND: Primary analysis of the phase III study WJTOG 3405 demonstrated superiority of progression-free survival (PFS) for gefitinib (G) in patients treated with the epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKI) gefitinib compared with cisplatin plus docetaxel (CD) as the first-line treatment of stage IIIB/IV or postoperative recurrent EGFR mutation-positive non-small-cell lung cancer. This report presents final overall survival (OS) data. PATIENTS AND METHODS: Patients were randomized between G (250 mg/day orally) and cisplatin (80 mg/m2 intravenously) plus docetaxel (60 mg/m2 i.v.), administered every 21 days for three to six cycles. After the exclusion of 5 patients, 172 patients (86 in each group, modified intention-to-treat population) were included in the survival analysis. OS was re-evaluated using updated data (data cutoff, 30 September 2013; median follow-up time 59.1 months). The Kaplan-Meier method and the log-rank test were used for analysis, and hazard ratios (HRs) for death were calculated using the Cox proportional hazards model. RESULTS: OS events in the G group and CD group were 68 (79.1%) out of 86 and 59 (68.6%) out of 86, respectively. Median survival time for G and CD were 34.9 and 37.3 months, respectively, with an HR of 1.252 [95% confidence interval (CI): 0.883-1.775, P = 0.2070]. Multivariate analysis identified postoperative recurrence and stage IIIB/IV disease as independent prognostic factors, with an HR of 0.459 (95% CI: 0.312-0.673, P < 0.001). Median survival time (postoperative recurrence versus stage IIIB/IV disease) were 44.5 and 27.5 months in the G group and 45.5 and 32.8 months in the CD group, respectively. CONCLUSION: G did not show OS benefits over CD as the first-line treatment. OS of patients with postoperative recurrence was better than that of stage IIIB/IV disease, even though both groups had metastatic disease.This study was registered with UMIN (University Hospital Medical Information Network in Japan), number 000000539.

Efficacy and safety analysis according to histology for S-1 in combination with carboplatin as first-line chemotherapy in patients with advanced non-small-cell lung cancer: updated results of the West Japan Oncology Group LETS study.

BACKGROUND: A phase III study (Lung Cancer Evaluation of TS-1) previously demonstrated noninferiority in terms of overall survival (OS) at interim analysis for carboplatin-S-1 compared with carboplatin-paclitaxel for first-line treatment of advanced non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS: A total of 564 patients were randomly assigned to receive either carboplatin on day 1 plus oral S-1 on days 1-14 or carboplatin-paclitaxel on day 1 every 21 days. Updated results and post hoc subgroup analysis according to tumor histology are presented. RESULTS: The updated analysis revealed a median OS of 15.2 months in the carboplatin-S-1 arm and 13.1 months in the carboplatin-paclitaxel arm, with a hazard ratio (HR) of 0.956 [95% confidence interval (CI) 0.793-1.151], consistent with the previous primary analysis. Median OS was 14.0 months in the carboplatin-S-1 arm and 10.6 months in the carboplatin-paclitaxel arm (HR 0.713; 95% CI 0.476-1.068) for patients with squamous cell carcinoma (SCC), with corresponding values of 15.5 and 13.9 months (HR 1.060; 95% CI 0.859-1.308) for those with non-SCC. CONCLUSIONS: These results establish the efficacy and safety of carboplatin-S-1 in patients with advanced NSCLC regardless of tumor histology.

Dose escalation study of carboplatin-pemetrexed followed by maintenance pemetrexed for elderly patients with advanced nonsquamous nonsmall-cell lung cancer.

BACKGROUND: This study was designed to determine the recommended dose of carboplatin-pemetrexed in elderly (≥75 years old), chemotherapy-naive patients with advanced nonsquamous nonsmall-cell lung cancer (NSCLC). PATIENTS AND METHODS: Patients received escalated doses of carboplatin and pemetrexed every 3 weeks for four cycles. Patients with an objective response and stable disease continued pemetrexed therapy until disease progression or unacceptable toxicity was observed. RESULTS: The combination of carboplatin at an area under the concentration-time curve (AUC) of 5, and 500 mg/m(2) pemetrexed, was determined to be the recommended dose for elderly patients with advanced nonsquamous NSCLC. Of 17 patients, 10 received a median of five cycles of pemetrexed maintenance therapy without unexpected or cumulative toxic effects. The study had an overall response rate of 47.1%. The median progression-free survival time was 142 days (95% confidence interval [CI] 68-216 days) and the median overall survival time was 461 days (95% CI 168-754 days). CONCLUSIONS: This combination was a tolerable and effective regimen, and recommended dose (RD) was carboplatin [area under the curve (AUC) of 5]/pemetrexed (500 mg/m(2)) every 3 weeks, in chemotherapy-naïve, elderly (≥75 years old) patients with advanced nonsquamous NSCLC.

Induction chemotherapy followed by gefitinib and concurrent thoracic radiotherapy for unresectable locally advanced adenocarcinoma of the lung: a multicenter feasibility study (JCOG 0402).

BACKGROUND: We conducted a feasibility study of induction chemotherapy followed by gefitinib and thoracic radiotherapy (TRT) for unresectable locally advanced adenocarcinoma of the lung. PATIENTS AND METHODS: Patients received induction chemotherapy with cisplatin (80 mg/m(2), days 1 and 22) and vinorelbine (25 mg/m(2), days 1, 8, 22, and 29) followed by gefitinib (250 mg daily, beginning on day 43, for 1 year) and TRT (60 Gy/30 fractions, days 57-98). The primary end point was feasibility, which was defined as the proportion of patients who completed 60 Gy of TRT and received >75% of the planned dose of gefitinib without developing grade 2 or worse pneumonitis. RESULTS: Of the 38 enrolled patients, 23 patients [60.5% ; 80% confidence interval (CI) 48.8-71.3] completed treatment without experiencing grade 2 or worse pneumonitis. During the chemoradiation phase, grade 3-4 alanine aminotransferase elevations were observed in 37.1% of the patients. The overall response rate was 73.0% . The median survival time was 28.5 months (95% CI 22.5-38.2), and the 2-year survival rate was 65.4% . CONCLUSIONS: Although the results did not meet our criterion for feasibility, the toxicity was acceptable. This treatment warrants further evaluation among patients with locally advanced non-small-cell lung cancer harboring epidermal growth factor receptor mutations.

Chemotherapy-induced neutropenia as a prognostic factor in advanced non-small-cell lung cancer: results from Japan Multinational Trial Organization LC00-03.

BACKGROUND: Neutropenia is a common adverse reaction of chemotherapy. We assessed whether chemotherapy-induced neutropenia could be a predictor of survival for patients with non-small-cell lung cancer (NSCLC). METHODS: A total of 387 chemotherapy-naïve patients who received chemotherapy (vinorelbine and gemcitabine followed by docetaxel, or paclitaxel and carboplatin) in a randomised controlled trial were evaluated. The proportional-hazards regression model was used to examine the effects of chemotherapy-induced neutropenia and tumour response on overall survival. Landmark analysis was used to lessen the bias of more severe neutropenia resulting from more treatment cycles allowed by longer survival, whereby patients who died within 126 days of starting chemotherapy were excluded. RESULTS: The adjusted hazard ratios for patients with grade-1 to 2 neutropenia or grade-3 to 4 neutropenia compared with no neutropenia were 0.59 (95% confidence interval (CI), 0.36-0.97) and 0.71 (95% CI, 0.49-1.03), respectively. The hazard ratios did not differ significantly between the patients who developed neutropenia with stable disease (SD), and those who lacked neutropenia with partial response (PR). CONCLUSION: Chemotherapy-induced neutropenia is a predictor of better survival for patients with advanced NSCLC. Prospective randomised trials of early-dose increases guided by chemotherapy-induced toxicities are warranted.

A phase II dose-ranging study of palonosetron in Japanese patients receiving moderately emetogenic chemotherapy, including anthracycline and cyclophosphamide-based chemotherapy.

BACKGROUND: The 5-HT(3) receptor antagonists (RAs) help maintain the standard of care, in various combinations with other agents, for prevention of chemotherapy-induced nausea and vomiting (CINV). Palonosetron is a new generation 5-HT(3) RA with indication not only acute but also delayed nausea and vomiting induced by moderately emetogenic chemotherapy (MEC). This study was carried out to determine the optimal dosage of palonosetron in combination with dexamethasone in patients in Japan. PATIENTS AND METHODS: This study evaluated the efficacy and safety of palonosetron in patients receiving MEC combined with dexamethasone. Patients received single doses of 0.075, 0.25, or 0.75 mg of palonosetron before MEC. Dexamethasone was infused before palonosetron, at 20 mg for the patients receiving paclitaxel (Taxol) and 8 mg for the patients not receiving paclitaxel. The primary end point was complete response (CR: no emetic episodes and no rescue medication) in the acute phase (0-24 h). RESULTS: In total, 204 patients (88 men, 116 women; 96 with paclitaxel, 108 without paclitaxel) were assessable for efficacy. No dose-response relationship was observed regarding the CR rate in the acute phase. CR rates increased dose dependently for delayed (24-120 h) and overall (0-120 h) phases in patients receiving anthracyclines and cyclophosphamide combination (AC/EC, n = 80); however, the difference in CR rates among doses was not statistically significant. The most commonly reported adverse events related to palonosetron were constipation and headache, confirming the class safety profile. CONCLUSION: This study indicates a statistically nonsignificant trend for the dose-response relationship for antiemetic protection in the delayed and overall phases in AC/EC patients (the regimen currently considered to be more emetogenic than MEC).

Endothelium removal augments endothelium-independent vasodilatation in rat mesenteric vascular bed.

BACKGROUND AND PURPOSE: The vascular endothelium regulates vascular tone by releasing various endothelium-derived vasoactive substances to counteract excess vascular response. We investigated whether the vascular endothelium regulates vasodilatation via released endothelium-derived contracting factors (EDCFs), by examining the effect of endothelium removal on responses to periarterial nerve stimulation (PNS) and various vasodilator agents. EXPERIMENTAL APPROACH: The rat mesenteric vascular bed was perfused with Krebs solution. Vasodilator responses to PNS and 5 min perfusion of vasodilator agents in preparations with endothelium were compared with those in the same preparations without endothelium. The endothelium was removed by 30 s perfusion with sodium deoxycholate. KEY RESULTS: Endothelium removal significantly augmented vasodilator responses to PNS and calcitonin gene-related peptide (CGRP), isoprenaline (beta-adrenoceptor agonist), SNP and 8-bromo-cGMP (8-Br-cGMP; cGMP analogue) but not BAY41-2272 (soluble guanylate cyclase activator). The augmentation of SNP-induced vasodilatation after denudation was much greater than that of CGRP- or isoprenaline-induced vasodilatation. In the preparations with an intact endothelium, L-NAME (nitric oxide synthase inhibitor) significantly augmented vasodilator responses to PNS and CGRP, isoprenaline, SNP and 8-Br-cGMP, but not BAY41-2272. Indomethacin (cyclooxygenase inhibitor) and seratrodast (thromboxane A(2) receptor antagonist), but not phosphoramidon (endothelin-1-converting enzyme inhibitor) or BQ-123 (selective endothelin type A receptor antagonists), significantly augmented vasodilator responses to PNS and CGRP, isoprenaline, SNP and BAY41-2272. CONCLUSION AND IMPLICATION: These results suggest that the endothelium in rat mesenteric arteries regulates and maintains vascular tone via counteracting not only vasoconstriction through releasing endothelium-derived relaxing factors, but also vasodilatation, in part by releasing an EDCF, thromboxane A(2).

Specific induction of metallothionein synthesis by mitochondrial oxidative stress.

Metallothionein (MT), a sulfhydryl-rich protein, may be increased by administration of a variety of agents, including metals, cytokines and oxidative stress agents. Mitochondria are a major source of reactive oxygen species, but antioxidant systems against mitochondrial free radicals are not fully understood. In this study, we examined the induction of MT synthesis by administration of mitochondrial-specific reactive oxygen generators such as antimycin A (AA), an electron transfer inhibitor, and 2,4-dinitrophenol (DNP), an uncoupling agent. Subcutaneous administration of AA to mice significantly increased the hepatic MT concentration in a dose- and time-dependent manner. AA slightly elevated glutathione peroxidase (GSHPx) activity, but the rate of increase in GSHPx (1.3-fold) was smaller than that in MT (11.8-fold). Other antioxidants such as catalase, manganese-superoxide dismutase (Mn-SOD), copper/zinc-superoxide dismutase (Cu/Zn-SOD) and GSHPx were not activated by AA treatment. Moreover, administration of DNP induced the synthesis of MT in the liver. Although DNP slightly elevated Mn-SOD activity, the rate of increase in Mn-SOD (1.3-fold) was smaller than that in MT (3.7-fold). Other antioxidants such as catalase, Cu/Zn-SOD and GSHPx were not activated by DNP treatment. These data suggest that MT plays a major role in protection against oxidative stress induced in mitochondria.

Population pharmacokinetic analysis of cisplatin and its metabolites in cancer patients: possible misinterpretation of covariates for pharmacokinetic parameters calculated from the concentrations of unchanged cisplatin, ultrafiltered platinum and total platinum.

BACKGROUND: Usually, total and filtered platinum concentrations in plasma are monitored after cisplatin administration. However, these concentrations represent a mixture of unchanged cisplatin and metabolites. In this work, we studied population pharmacokinetic analysis based on these platinum concentrations. METHODS: Twenty-seven patients (23 males, four females) were administered cisplatin (60-100 mg/m2) with intravenous constant infusion for 90 min. Blood samples were taken at about three points per patient. The concentrations of cisplatin and platinum in the plasma were determined by high-performance liquid chromatography and atomic absorption spectrometry, respectively. Population pharmacokinetic analysis was performed using the program NONMEM (Version V) with the one- or two-compartment model with zero-order infusion. RESULTS: The clearance and volume of distribution for all platinum species studied were significantly related to the body surface area of the patients. Only the clearance of filtered platinum was significantly related to urinary N-acetyl-beta-D-glucosaminidase and the other covariates were not related to these pharmacokinetic parameters with respect to unchanged cisplatin and total platinum concentrations. CONCLUSION: The dosage regimen based on the filtered platinum concentration which is usually monitored may result in possible misinterpretation because the detected covariate is different between unchanged cisplatin and filtered platinum.

Phase II trial of daily low-dose carboplatin and thoracic radiotherapy in elderly patients with locally advanced non-small cell lung cancer.

BACKGROUND: The purpose of this study was to investigate the feasibility of concurrent thoracic radiotherapy (TRT) and daily low-dose carboplatin (CBDCA) in elderly patients with locally advanced non-small cell lung cancer (NSCLC) and to estimate tumor response, toxicity and survival. METHODS: Forty patients were entered in a multicenter phase II study. All were patients with pathologically documented unresectable stage IIIA or IIIB or medically inoperable stage I, II NSCLC. CBDCA 30 mg/m2 was given on days 1-5 in weeks 1-4 concurrently with TRT, mainly for radiosensitization. TRT was started 1 h after CBDCA (30 min infusion) was given. TRT was given in 2 Gy/fraction/day, 5 days a week for a total of 50-60Gy. RESULTS: Thirty-eight patients were assessable for treatment response and toxicity. One patient had a CR and 18 patients PRs with a response rate of 50% (95% CI, 33.4-66.6%). The main toxicities were hematological toxicity. Other toxicities were grade > or =2 esophagitis in one patient, grade 3 nausea/vomiting in one and grade > or =3 pulmonary toxicity in two. There was one treatment-related death due to pulmonary toxicity. For stage IIIA + IIIB patients, the median survival time was 15.1 months and 1-and 2-year actuarial survival rates were 52.6 and 20.5%, respectively. For stage I + II patients, 1- and 3-year actuarial survival rates were 90.9 and 69.3%, respectively. CONCLUSIONS: The data suggest that TRT with daily low-dose CBDCA in elderly patients is effective and feasible because of its low toxicity and survival.

Immunohistochemical analysis of Bcl-2 protein in early squamous cell carcinoma of the bronchus treated with photodynamic therapy.

Photodynamic therapy (PDT) in early squamous cell carcinoma of the bronchus has been shown to result in complete response (CR) and cure. However, local recurrence after PDT develops frequently even after complete remission. Because the effect of PDT had been reported to depend on apoptosis, and apoptosis is inhibited by bcl-2 protein, the relationship between the expression of bcl-2 protein and local recurrence after PDT was examined immunohistochemically. From 1983 to 1997, 50 patients with 59 early squamous cell carcinoma of the bronchus received PDT, and a CR was obtained in 43 lesions (72.8%). As there was no recurrence among tumours that were disease-free for more than 2 years, in this study the tumours were defined as cured when recurrence did not occur 2 years subsequent to the receiving of PDT. Of these CR lesions, 31 carcinomas (53.4%) resulted in a cure. Bcl-2 immunoreactivity was detected in 23 tumours (46.9%) and p53 immunoreactivity was detected in 22 tumours (44.9%). When all tumours were divided into either a large tumour with a longitudinal tumour length of 10 mm or more, or a small tumour with a length of less than 10 mm, the large tumour expressed more bcl-2 protein than the small tumour (P = 0.0155). The degree of bcl-2 expression was significantly related with tumour size (P = 0.0155). The expression of bcl-2 and p53 protein was not associated with the cure rate due to PDT. Tumour length and T status in TNM staging were significantly related to the cure by univariate analysis. T status was the only predictor of the cure according to mutivariate analysis. Of 42 CR lesions, the expression of neither bcl-2 nor p53 protein was associated with local recurrence; only T status was significantly associated (P = 0.008). The relationship between the expression of oncoprotein and local recurrence after PDT was not documented in this study. The success of PDT may depend on the exact assessment of tumour size under optimized PDT illumination.

[Autopsy case of adenoid cystic carcinoma of the trachea: endobronchial treatment improves quality of life].

A 67-year-old man presented with dyspnea on exertion. Bronchoscopic examination revealed a tumor arising from the middle portion of the trachea and extending to the right main bronchus. The pathological diagnosis was adenoid cystic carcinoma. Radiotherapy and subsequent endobronchial electrocautery were performed, and elicited a partial response. In the clinical course. Dumon and Ultraflex stents were placed in the trachea asynchronically. Brachytherapy and esophageal stent placement were also performed for tumor control in the trachea and esophagus. Autopsy revealed that the tumor had invaded the trachea and esophagus, and bacterial mediastinitis was also demonstrated. Because the tumor was successfully controlled during the following 4 years and 9 months, we concluded that endobronchial therapy such as stent placement or electrocautery is useful for maintaining good quality of life.

High-resolution CT findings of diffuse bronchioloalveolar carcinoma in 38 patients.

OBJECTIVE: The purpose of this study was to analyze the high-resolution CT features of diffuse bronchioloalveolar carcinoma and determine the useful findings in differential diagnosis. MATERIALS AND METHODS: High-resolution CT scans of 38 patients with pathologically proven diffuse bronchioloalveolar carcinoma were reviewed. Sequential CT scans were obtained in 15 patients. The high-resolution CT findings were compared with those of eosinophilic pneumonia (n = 22), multiple pulmonary metastases (n = 12), and tuberculosis (bronchogenic: n = 22; miliary: n = 12). RESULTS: High-resolution CT findings of diffuse bronchioloalveolar carcinoma included ground-glass opacity (n = 29), consolidation (n = 29), nodules (n = 28), centrilobular nodules (n = 26), peripheral distribution (n = 19), and air bronchogram (n = 18). According to the major features, high-resolution CT findings of diffuse bronchioloalveolar carcinoma could be classified into three patterns: predominantly ground-glass (n = 4), consolidative (n = 22), and multinodular (n = 12). Most patients with diffuse bronchioloalveolar carcinoma had a mixture of these findings. The frequency of findings of diffuse bronchioloalveolar carcinoma on high-resolution CT was not different from that of tuberculosis, but the predominant distribution of the nodules and areas of ground-glass attenuation differed between the two. Difference in distribution between bronchioloalveolar carcinoma and bronchogenic tuberculosis included ground-glass opacity remote from the consolidation and a lower lung predominance. CONCLUSION: Although these high-resolution CT findings are not specific, the combination of consolidation and nodules and the coexistence of centrilobular nodules and remote areas of ground-glass attenuation are characteristic of diffuse bronchioloalveolar carcinoma.

Solitary squamous papilloma of the bronchus associated with human papilloma virus type 11.

A 79-year-old female presented with persistent dry cough, and a chest radiograph showed a mass shadow in the right upper lung. Bronchoscopic examination revealed that the right main bronchus was severely obstructed by a polypoid tumor, which was diagnosed pathologically as squamous papilloma. After the failure of the attempted endobronchial snare to remove the tumor, right upper lobectomy was performed. The polymerase chain reaction (PCR) examination showed the presence of human papilloma virus type 11 DNA in the resected tumor, suggesting that this virus was the cause of this solitary squamous papilloma of the lung.

[Two cases of metastasizing benign leiomyomatosis from myoma uteri].

Case 1. A 50-year-old woman was referred to our hospital because of multiple bilateral small round lesion on chest radiography. She had undergone total hysterectomy for myoma uteri at the age of 33. She underwent thoracoscopic tumor excision at left lung. The lesion was proved benign. Right side lesions were laterly excised using thoracotomy. Case 2. A 49-year-old woman was referred to us because of two ovoid lesion at left lung area of chest radiography. She also had undergone total hysterectomy for myoma uteri at the age of 37. She underwent tumor extirpation using thoracotomy. All samples of two patients revealed, pathologically, lesions were consisted of benign spindle-like calls similar to those of myoma uteri. Therefore, we consider these lesions were pulmonary metastasis of myoma uteri. Myoma uteri has certain potential of metastasizing to the lung, in spite of benign disease.

Phase II trial of carboplatin plus oral etoposide for elderly patients with small-cell lung cancer.

A phase II trial was conducted to evaluate the efficacy and toxicity of the Egorin's carboplatin dosing formula with 14-day oral etoposide in 38 elderly patients with small-cell lung cancer (SCLC). The overall response rate was 81%. Median survival times were 15.1 months for 16 limited-disease (LD) and 8.6 months for 22 extensive-disease (ED) patients. Myelosuppression was the principal side-effect. This regimen is an active regimen in the treatment of elderly SCLC patients.

Utility of hyaluronic acid in pleural fluid for differential diagnosis of pleural effusions: likelihood ratios for malignant mesothelioma.

The level of hyaluronic acid (HA) was determined in the pleural fluid of 99 patients, including 19 with malignant mesothelioma, 27 with lung cancer, 1 with breast cancer, 1 with mediastinal tumor and 51 with non-malignant diseases. With a cut-off level at 100 micrograms/ml, the pleural fluid concentration of HA was high in 36.8% of patients (7 of 19) with malignant mesothelioma and 1.3% of patients (1 of 80) with lung cancer and other malignant and non-malignant diseases. The mean concentration of pleural fluid HA was significantly higher in patients with mesothelioma than in those with lung cancer and other malignant and non-malignant diseases. The pre-test probability of MM was 5.9% in this series. The LRs for > or = 100, 50-99 and < or = 49 micrograms/ml are 28.3, 3.3 and 0.5, respectively; these put the post-test probabilities at 64, 17 and 3%, respectively. Indeed, in cases of uncommon disease such as MM, the post-test probability is low even if the cut-off level of HA is > or = 100 micrograms/ml. The discrimination between malignant mesothelioma and lung cancer needs special attention. In these two diseases, the LRs of MM for pleural fluid CEA > 30, 10-30 and < 10 ng/ml were 0.2, 1.9 and 2.4, respectively. The pre-test probability of MM for HA > or = or 100 micrograms/ml is 64%. Furthermore, because the LR for CEA is < 10 ng/ml, the post-test probability is 81%. When the combination of two markers is considered, the high level of HA and the low level of CEA may be useful for the differential diagnosis of MM from pleuritis carcinomatosa.