50 Patients with Malignant Mesothelioma of Both the Pleura and Peritoneum: A Single-Institution Experience.

BACKGROUND: The most common sites of malignant mesothelioma are the pleura and peritoneum, but little is known about the incidence, prognosis, or treatment of patients with disease in both cavities. Previous series suggest that multimodality treatment improves overall survival for pleural or peritoneal disease, but studies typically exclude patients with disease in both cavities. Despite limitations, this investigation is the only study to broadly examine outcomes for patients with malignant mesothelioma in both the pleural and peritoneal cavities. METHODS: This study retrospectively examined 50 patients with both pleural and peritoneal mesothelioma treated with the intent to prolong survival. The primary end point was overall survival from the initial operative intervention. RESULTS: The median overall survival was 33.9 months from the initial intervention. Female gender and intraperitoneal dwell chemotherapy were independent predictors of overall survival. Within 1 year after the initial diagnosis, second-cavity disease was diagnosed in 52% of the patients. The median time to the second-cavity diagnosis for those with a diagnosis 1 year after the initial diagnosis was 30 months. CONCLUSIONS: Well-selected patients with both pleural and peritoneal mesothelioma have a survival benefit over palliative treatment that is comparable with that seen in single-cavity disease. The presence of disease in both cavities is not a contraindication to multimodality treatment aimed at prolonging survival, whether the disease is diagnosed synchronously or metachronously. Patients with an initial diagnosis of single cavity disease are at the highest risk for identification of second-cavity disease within the first year after diagnosis.

Recurrence of Optimally Treated Malignant Peritoneal Mesothelioma with Cytoreduction and Heated Intraperitoneal Chemotherapy.

BACKGROUND: The prognosis for patients with diffuse malignant peritoneal mesothelioma has dramatically improved with cytoreductive surgery and intraperitoneal chemotherapy. Little is known about disease recurrence after treatment. We analyzed the time to and predictors of recurrence in a large cohort of optimally treated patients. METHODS: We examined 113 patients completing a two-stage cytoreduction and intraperitoneal chemotherapy protocol. All patients achieved optimal surgical resection with completeness of cytoreduction (CC) score ≤ 1 and were divided into two groups based on absence (Group A) or presence (Group B) of gross disease at the outset of the second operation. Predictors of disease recurrence and recurrence-free survival (RFS) were determined using Cox proportional hazard regression modeling, and estimates were obtained by using the Kaplan-Meier method. RESULTS: Forty-six percent of patients had no gross evidence of disease at the second operation; the remaining 54% were cytoreduced to CC ≤ 1 (Group B). Forty-two percent of patients developed disease recurrence with a median recurrence-free survival of 38.5 months for the cohort; 79% of these received a form of iterative treatment. There was no statistically significant difference in recurrence-free survival between Group A (median RFS: 44.6 months) and B (median RFS: 35.5 months) (log-rank test, p = 0.06). Additionally, the only variable significantly associated with RFS was male gender (hazard ratio [HR] 1.98, 95% confidence interval [CI] 1.16-3.38). CONCLUSIONS: Absence of gross disease at the second operation was not statistically protective against recurrence compared with presence of quantifiable residual disease (Group B) that was effectively cytoreduced. Long-term disease surveillance is recommended, because recurrence continues years after treatment. Where a question of recurrence arises on surveillance, males may benefit from a higher degree of suspicion.

Body surface area predicts plasma oxaliplatin and pharmacokinetic advantage in hyperthermic intraoperative intraperitoneal chemotherapy.

BACKGROUND: Hyperthermic intraoperative intraperitoneal chemotherapy (HIPEC) is used to treat peritoneal surface-spreading malignancies to maximize local drug concentrations while minimizing systemic effects. The pharmacokinetic advantage of HIPEC is defined as the intraperitoneal to intravascular ratio of drug concentrations. We hypothesized that body surface area (BSA) would correlate with the pharmacokinetic advantage of HIPEC. Because oxaliplatin is administered in 5 % dextrose, we hypothesized that BSA would correlate with glycemia. METHODS: We collected blood and peritoneal perfusate samples from ten patients undergoing HIPEC with a BSA-based dose of 250 mg/m(2) oxaliplatin, and measured drug concentrations by inductively coupled plasma mass spectrophotometry. We monitored blood glucose for 24 h postoperatively. Areas under concentration-time curves (AUC) were calculated by trapezoidal rule. Pharmacokinetic advantage was calculated by (AUC[peritoneal fluid]/AUC[plasma]). We used linear regression to test for statistical significance. RESULTS: Higher BSA was associated with lower plasma oxaliplatin AUC (p = 0.0075) and with a greater pharmacokinetic advantage (p = 0.0198) over the 60-minute duration of HIPEC. No statistically significant relationships were found between BSA and blood glucose AUC or peak blood glucose levels. CONCLUSIONS: Higher BSA is correlated with lower plasma drug levels and greater pharmacokinetic advantage in HIPEC, likely because of increased circulating blood volume with inadequate time for equilibration. Plasma glucose levels after oxaliplatin HIPEC were not clearly related to BSA.

Phase II trial of pemetrexed and gemcitabine in chemotherapy-naive malignant pleural mesothelioma.

PURPOSE: Pemetrexed and gemcitabine have single-agent activity in malignant pleural mesothelioma (MPM). The combination of pemetrexed/gemcitabine has not previously been studied in MPM to our knowledge. PATIENTS AND METHODS: Patients with histologic or cytologic diagnosis of MPM were included. Cohort 1 received gemcitabine 1,250 mg/m(2) on days 1 and 8, with pemetrexed 500 mg/m(2) on day 8, and cohort 2 received gemcitabine 1,250 mg/m(2) on days 1 and 8, with pemetrexed 500 mg/m(2) on day 1. Cycles were repeated every 21 days; all patients were supplemented with folic acid and vitamin B(12) and received dexamethasone. RESULTS: One hundred eight patients (cohort 1, n = 56; cohort 2, n = 52) with pleural mesothelioma were enrolled. Among assessable patients, response rate was 26.0% in cohort 1 and 17.1% in cohort 2. Median time to disease progression was 4.34 months for cohort 1 and 7.43 months for cohort 2. Median survival was 8.08 months for cohort 1 (1-year survival = 31.14%) and 10.12 months for cohort 2 (1-year survival = 45.80%). In cohorts 1 and 2, incidence of grade 4 neutropenia was 25.0% and 29.4%, grade 4 thrombocytopenia was 14.3% and 3.9%, grade 3 or 4 anemia was 5.4% and 5.9%, and grade 3 or 4 fatigue was 23.2% and 15.7%, respectively. CONCLUSION: The combination of pemetrexed and gemcitabine resulted in moderate clinical activity in MPM. However, the median survival times are similar to those with single-agent pemetrexed and inferior to outcomes observed with cisplatin in combination with an antifolate.