Postoperative non-steroidal anti-inflammatory drug use and oncological outcomes of rectal cancer.

BACKGROUND: Non-steroidal anti-inflammatory drugs (NSAIDs) are known to suppress the inflammatory response after surgery and are often used for pain control. This study aimed to investigate NSAID use after radical surgical resection for rectal cancer and long-term oncological outcomes. METHODS: A cohort of patients who underwent anterior resection for rectal cancer between 2007 and 2013 in 15 hospitals in Sweden was investigated retrospectively. Data were obtained from the Swedish Colorectal Cancer Registry and medical records; follow-up was undertaken until July 2019. Patients who received NSAID treatment for at least 2 days after surgery were compared with controls who did not, and the primary outcome was recurrence-free survival. Cox regression modelling with confounder adjustment, propensity score matching, and an instrumental variables approach were used; missing data were handled by multiple imputation. RESULTS: The cohort included 1341 patients, 362 (27.0 per cent) of whom received NSAIDs after operation. In analyses using conventional regression and propensity score matching, there was no significant association between postoperative NSAID use and recurrence-free survival (adjusted hazard ratio (HR) 1.02, 0.79 to 1.33). The instrumental variables approach, including individual hospital as the instrumental variable and clinicopathological variables as co-variables, suggested a potential improvement in the NSAID group (HR 0.61, 0.38 to 0.99). CONCLUSION: conventional modelling did not demonstrate an association between postoperative NSAID use and recurrence-free survival in patients with rectal cancer, although an instrumental variables approach suggested a potential benefit.

A field study of environmental impacts at a bleached kraft pulp mill site on the Baltic Sea coast.

The rate of technical development in bleaching of chemical pulp and the upgrading of process control and wastewater treatment systems in the pulp industry have been extremely rapid over the past few years. When assessing the environmental impacts of bleached kraft pulp mill effluents (BKMEs), it is therefore more important than ever to carefully characterize the bleaching process, the composition of the treated effluent, and the degree of exposure of sensitive target organisms in the receiving water body. These requirements have not always been fulfilled in previous reports on biological effects of BKMEs in Scandinavia. This work presents the results of a comprehensive field study of the impacts of a 350,000-tonne kraft mill, bleaching softwood and hardwood pulp in campaigns according to the sequence O(D25,C70+D5)(EOP)D(EP)D. The effluent is treated in an aerated lagoon with a mean retention time of 8-9 days, practically eliminating chlorate and resin acids, and reducing the discharge of adsorbable organic halogen (AOX) to an average of 1 t/day (1.3 and 0.4 kg/ADt for softwood and hardwood, respectively). The treated effluent is discharged through a 1.3-km-long diffuser, at a water depth of 9-12 m, into a well ventilated coastal area, giving a 1000-fold dilution within 3-4 km from the diffuser. The actual exposure of the coastal ecosystem to BKME components was determined by analysis of extractable organic chlorine in suspended solids and of conjugates of chlorophenolics in the bile of feral perch. Despite a major damage to the benthic communities that occurred about 10 years ago, and was due to large chlorate discharges at the time, no direct detrimental effects on benthic flora and fauna could be ascribed to the present BKME discharge. Instead, a clear recovery of the Fucus community, although not yet completed, could be demonstrated. Studies of the composition, abundance and biomass of the fish community, the recruitment and survival of fish fry, and the physiological status of perch, using a set of biomarkers, revealed that even in the most BKME-exposed area, only minor effects were detected. These effects were related to eutrophication/enrichment rather than to the action of toxic substances. The general effect picture, thus, was essentially of a different type than the one recorded in previous studies of mills, which used older technology and less effective process and effluent treatment control, and which were discharging into enclosed, shallow bays of the Baltic Sea.