Staging laparoscopy with peritoneal lavage to identify peritoneal metastases and free intraperitoneal cancer cells in the management of locally advanced gastric cancer.

INTRODUCTION: Gastric cancer often presents in advanced stage with a significant risk for peritoneal dissemination. Staging laparoscopy can be used to detect peritoneal carcinomatosis (PC+) and free cancer cells in peritoneal lavage cytology (CY+). The current study aimed to present the outcomes of staging laparoscopy and the prognosis of PC+ and CY+ in a Swedish high-volume center. MATERIALS AND METHODS: A cohort study including all consecutive patients with locally advanced gastric cancer who underwent staging laparoscopy between February 2008 and October 2022. The laparoscopy findings were categorized as PC+, PC-CY+ (positive cytology without peritoneal carcinomatosis) or negative laparoscopy (PC-CY-). The primary endpoint was overall survival (OS) stratified by laparoscopy findings. The secondary endpoint was OS within each laparoscopy finding group stratified by subsequent treatment. RESULTS: Among 168 patients who underwent staging laparoscopy, 78 patients (46%) had PC-CY-, 29 patients (17%) had PC-CY+ and 61 patients (36%) had PC+. Decreased OS was observed for both PC-CY+ patients (aHR 2.14, 95% CI 1.13-4.06) and PC+ patients (aHR 5.36, 95% CI 3.21-8.93), compared to PC-CY-. Patients with PC-CY+ who converted to PC-CY- after chemotherapy and underwent tumor resection seemed to have a better prognosis compared to patients with persisting PC-CY+. CONCLUSIONS: Staging laparoscopy is an important tool in the staging of locally advanced gastric cancer. Tumor resection for patients with PC-CY+ who convert to PC-CY- may lead to improved survival for these patients.

Diagnostic workup for esophageal cancer patients can be improved with checklists and clearer protocols; a comparative study between two tertiary centers in Europe.

BACKGROUND: Rapid and complete workup of newly diagnosed esophageal cancer is vital for a timely, individual and high-quality treatment strategy. The aim of this study was to uncover potential delay, inefficiencies and non-contributing investigations in the diagnostic process in two tertiary referral centers. METHODS: This retrospective cohort study included all newly diagnosed esophageal cancer patients referred to or diagnosed in the Amsterdam UMC and Karolinska University Hospital between July 2020 and July 2021. Radiology, pathological assessment and multidisciplinary team meeting reports were reviewed. To assess time interval from diagnosis to treatment, dates of diagnosis, admittance to referral hospital, MDT meeting and start of treatment were collected. RESULTS: In total, 252 esophageal cancer patients were included, 187 were treated with curative intent. Curatively treated patients had a mean age of 66 years, were predominantly male (74.9 %) with an adenocarcinoma (71.1 %). Curatively treated patients had a median time from diagnosis to referral of seven days (IQR:0-11) and of 35 days (IQR:28-45) between diagnosis and start of treatment. Main reasons for the significant (P < 0.001) differences in time between diagnosis and treatment between centers, Amsterdam UMC (39 days) vs Karolinska (27 days), were need for additional diagnostics (47.8 %) and differences in referral routine. Gastroscopy was repeated in 32.2 % of patients, mainly for further anatomical mapping. CONCLUSION: Significant time differences between centers in the path from diagnosis to start treatment can be explained by differences in workup approach, referral routines and MDT meeting regulations. Repeat of gastroscopy can be prevented with clearer endoscopy guidelines.

Major Intraoperative Complications During Minimally Invasive Esophagectomy.

BACKGROUND: Studies have shown minimally invasive esophagectomy (MIE) to be a feasible surgical technique in treating esophageal carcinoma. Postoperative complications have been extensively reviewed, but literature focusing on intraoperative complications is limited. The main objective of this study was to report major intraoperative complications and 90-day mortality during MIE for cancer. METHODS: Data were collected retrospectively from 10 European esophageal surgery centers. All intention-to-treat, minimally invasive laparoscopic/thoracoscopic esophagectomies with gastric conduit reconstruction for esophageal and GE junction cancers operated on between 2003 and 2019 were reviewed. Major intraoperative complications were defined as loss of conduit, erroneous transection of vascular structures, significant injury to other organs including bowel, heart, liver or lung, splenectomy, or other major complications including intubation injuries, arrhythmia, pulmonary embolism, and myocardial infarction. RESULTS: Amongst 2862 MIE cases we identified 98 patients with 101 intraoperative complications. Vascular injuries were the most prevalent, 41 during laparoscopy and 19 during thoracoscopy, with injuries to 18 different vessels. There were 24 splenic vascular or capsular injuries, 11 requiring splenectomies. Four losses of conduit due to gastroepiploic artery injury and six bowel injuries were reported. Eight tracheobronchial lesions needed repair, and 11 patients had significant lung parenchyma injuries. There were 2 on-table deaths. Ninety-day mortality was 9.2%. CONCLUSIONS: This study offers an overview of the range of different intraoperative complications during minimally invasive esophagectomy. Mortality, especially from intrathoracic vascular injuries, appears significant.

Predictive value of diffusion MRI-based parametric response mapping for prognosis and treatment response in glioblastoma.

BACKGROUND: Early detection of treatment response is important for the management of patients with malignant brain tumors such as glioblastoma to assure good quality of life in relation to therapeutic efficacy. AIM: To investigate whether parametric response mapping (PRM) with diffusion MRI may provide prognostic information at an early stage of standard therapy for glioblastoma. MATERIALS AND METHODS: This prospective study included 31 patients newly diagnosed with glioblastoma WHO grade IV, planned for primary standard postoperative treatment with radiotherapy 60Gy/30 fractions with concomitant and adjuvant Temozolomide. MRI follow-up including diffusion and perfusion weighting was performed at 3 T at start of postoperative chemoradiotherapy, three weeks into treatment, and then regularly until twelve months postoperatively. Regional mean diffusivity (MD) changes were analyzed voxel-wise using the PRM method (MD-PRM). At eight and twelve months postoperatively, after completion of standard treatment, patients were classified using conventional MRI and clinical evaluation as either having stable disease (SD, including partial response) or progressive disease (PD). It was assessed whether MD-PRM differed between patients having SD versus PD and whether it predicted the risk of disease progression (progression-free survival, PFS) or death (overall survival, OS). A subgroup analysis was performed that compared MD-PRM between SD and PD in patients only undergoing diagnostic biopsy. MGMT-promotor methylation status (O6-methylguanine-DNA methyltransferase) was registered and analyzed with respect to PFS, OS and MD-PRM. RESULTS: Of the 31 patients analyzed: 21 were operated by resection and ten by diagnostic biopsy. At eight months, 19 patients had SD and twelve had PD. At twelve months, ten patients had SD and 20 had PD, out of which ten were deceased within twelve months and one was deceased without known tumor progression. Median PFS was nine months, and median OS was 17 months. Eleven patients had methylated MGMT-promotor, 16 were MGMT unmethylated, and four had unknown MGMT-status. MD-PRM did not significantly predict patients having SD versus PD neither at eight nor at twelve months. Patients with an above median MD-PRM reduction had a slightly longer PFS (P = 0.015) in Kaplan-Maier analysis, as well as a non-significantly longer OS (P = 0.099). In the subgroup of patients only undergoing biopsy, total MD-PRM change at three weeks was generally higher for patients with SD than for patients with PD at eight months, although no tests were performed. MGMT status strongly predicted both PFS and OS but not MD-PRM change. CONCLUSION: MD-PRM at three weeks was not demonstrated to be predictive of treatment response, disease progression, or survival. Preliminary results suggested a higher predictive value in non-resected patients, although this needs to be evaluated in future studies.

Oncological outcomes of standard versus prolonged time to surgery after neoadjuvant chemoradiotherapy for oesophageal cancer in the multicentre, randomised, controlled NeoRes II trial.

BACKGROUND: The optimal time to surgery (TTS) after neoadjuvant chemoradiotherapy (nCRT) for oesophageal cancer is unknown and has traditionally been 4-6 weeks in clinical practice. Observational studies have suggested better outcomes, especially in terms of histological response, after prolonged delay of up to 3 months after nCRT. The NeoRes II trial is the first randomised trial to compare standard to prolonged TTS after nCRT for oesophageal cancer. PATIENTS AND METHODS: Patients with resectable, locally advanced oesophageal cancer were randomly assigned to standard delay of surgery of 4-6 weeks or prolonged delay of 10-12 weeks after nCRT. The primary endpoint was complete histological response of the primary tumour in patients with adenocarcinoma (AC). Secondary endpoints included histological tumour response, resection margins, overall and progression-free survival in all patients and stratified by histologic type. RESULTS: Between February 2015 and March 2019, 249 patients from 10 participating centres in Sweden, Norway and Germany were randomised: 125 to standard and 124 to prolonged TTS. There was no significant difference in complete histological response between AC patients allocated to standard (21%) compared to prolonged (26%) TTS (P = 0.429). Tumour regression, resection margins and number of resected lymph nodes, total and metastatic, did not differ between the allocated interventions. The first quartile overall survival in patients allocated to standard TTS was 26.5 months compared to 14.2 months after prolonged TTS (P = 0.003) and the overall risk of death during follow-up was 35% higher after prolonged delay (hazard ratio 1.35, 95% confidence interval 0.94-1.95, P = 0.107). CONCLUSION: Prolonged TTS did not improve histological complete response or other pathological endpoints, while there was a strong trend towards worse survival, suggesting caution in routinely delaying surgery for >6 weeks after nCRT.

Re-irradiation in Paediatric Tumours of the Central Nervous System: National Guidelines from the Swedish Workgroup of Paediatric Radiotherapy.

There is a lack of clinical protocols for re-irradiation in paediatric central nervous system (CNS) tumours. To fill this void, the Swedish Workgroup of Paediatric Radiotherapy (SBRTG) compiled national guidelines on re-irradiation in paediatric CNS tumours (diffuse intrinsic pontine glioma, ependymoma, germinoma and medulloblastoma). These have been in clinical practice since 2019 in all paediatric radiotherapy centres in Sweden. Since the implementation, the guidelines have been complemented with a yearly review on clinical outcome and toxicities in all paediatric patients treated according to the guidelines. This article presents the Swedish national guidelines on re-irradiation in paediatric CNS tumours.

Feasibility and Safety of Laparoscopic D2 Gastrectomy in Combination with Pressurized Intraperitoneal Aerosol Chemotherapy (PIPAC) in Patients with Gastric Cancer at High Risk of Recurrence-The PIPAC-OPC4 Study.

BACKGROUND: Patients with gastric adenocarcinoma (GAC) are at high risk of peritoneal recurrence despite perioperative chemotherapy and radical resection. This study evaluated feasibility and safety of laparoscopic D2 gastrectomy in combination with pressurized intraperitoneal aerosol chemotherapy (PIPAC). METHODS: This was a prospective, controlled bi-institutional study in patients with GAC at high risk of recurrence treated with PIPAC with cisplatin and doxorubicin (PIPAC C/D) after laparoscopic D2 gastrectomy. High risk was defined as a poorly cohesive subtype with predominance of signet-ring cells, clinical stage ≥ T3 and/or ≥ N2, or positive peritoneal cytology. Peritoneal lavage fluid was collected before and after resection. Cisplatin (10.5 mg/m2) and doxorubicin (2.1 mg/m2) were aerosolized after anastomosis (flow 0.5-0.8 ml/s, maximum pressure 300 PSI). Treatment was feasible and safe if ≤ 20% had Dindo-Clavien ≥ 3b surgical complications or CTCAE ≥ 4 medical adverse events within 30 days. Secondary outcomes were length of stay (LOS), peritoneal lavage cytology, and completion of postoperative systemic chemotherapy. RESULTS: Twenty-one patients were treated with a D2 gastrectomy and PIPAC C/D. The median age was 61 years (range 24-76), there were eleven female patients, and 20 patients had preoperative chemotherapy. There was no mortality. Two patients had grade 3b complications that were potentially related to PIPAC C/D (one anastomotic leakage, and one late duodenal blow-out). One patient had severe neutropenia, and nine patients had moderate pain. The LOS was 6 days (4-26). One patient had positive peritoneal lavage cytology before resection, and none were positive after. Fifteen patients had postoperative chemotherapy. CONCLUSIONS: Laparoscopic D2 gastrectomy in combination with PIPAC C/D is feasible and safe.

ERAS guidelines-driven upper gastrointestinal contrast study after esophagectomy can detect delayed gastric conduit emptying and improve outcomes.

BACKGROUND: Delayed gastric conduit emptying can occur after esophagectomy and has been shown to be associated with increased risk for postoperative complications. Application of a standardized clinical protocol after esophagectomy including an upper gastrointestinal contrast study has the potential to improve postoperative outcomes. METHODS: Prospective cohort including all patients operated with esophagectomy at two high-volume centers for esophageal surgery. The standardized clinical protocol included an upper gastrointestinal contrast study on day 2 or 3 after surgery. All images were compiled and evaluated for the purpose of the study. Clinical data was collected in IRB approved institutional databases at the participating centers. RESULTS: The study included 119 patients treated with esophagectomy of whom 112 (94.1%) completed an upper gastrointestinal contrast study. The results showed that 8 (7.1%) patients had radiological delayed gastric conduit emptying defined as no emptying of contrast through the pylorus. Partial conduit emptying was seen in 34 (30.4%) patients, and 70 (62.5%) patients had complete conduit emptying. Complete or partial emptying was associated with significantly earlier nasogastric tube removal (3 vs. 6 days) and hospital discharge 8 vs. 17 days, P < 0.001). Radiological signs of delayed gastric conduit emptying were shown to be associated with increased risk of postoperative complications. There was, however, no association with severe postoperative complications according to Clavien-Dindo score, pulmonary complications, anastomotic leak or need for intensive care. CONCLUSION: The results of the study demonstrate that postoperative upper gastrointestinal contrast studies can be used to assess the level of emptying of the gastric conduit after esophagectomy. Application of upper gastrointestinal contrast study in the ERAS guidelines-driven standardized clinical pathway after esophagectomy has the potential to improve postoperative outcomes.

Dosimetric and Clinical Predictors for Acute and Late Gastrointestinal Toxicity Following Chemoradiotherapy of Locally Advanced Anal Cancer.

AIMS: To analyse dosimetric and clinical predictors for acute and late gastrointestinal toxicity following chemoradiotherapy of anal cancer. MATERIALS AND METHODS: Consecutive patients with locally advanced (T2 ≥4 cm - T4 or N+) anal cancer were selected from an institutional database (n = 114). All received intensity-modulated radiotherapy with concomitant 5-fluorouracil and mitomycin C. Gastrointestinal toxicity was retrospectively graded according to Common Terminology Criteria for Adverse Events (CTCAE) version 5.0 and bowel cavity, small bowel and large bowel were contoured. Dosimetric and clinical variables were tested for associations with acute grade ≥3 gastrointestinal toxicity and late grade ≥2 gastrointestinal toxicity using the Mann-Whitney test, area under receiver operating characteristic curve (AUC) and logistic regression. RESULTS: The median follow-up was 40 months. Acute grade ≥3 gastrointestinal toxicity was seen in 51 (44.7%) of the patients; late grade ≥2 gastrointestinal toxicity was seen in 36 of the patients (39.6% of 91 patients with >1 year recurrence-free follow-up). Bowel cavity V30Gy was the best dosimetric predictor for acute gastrointestinal toxicity (AUC 0.633; P = 0.02). Large bowel V20Gy was the best dosimetric predictor for late gastrointestinal toxicity (AUC 0.698; P = 0.001) but showed no association with acute gastrointestinal toxicity. In multivariate logistic regression, increasing age was significantly associated with acute gastrointestinal toxicity; smoking and large bowel V20Gy were significantly associated with late gastrointestinal toxicity. Patients who experienced acute grade ≥3 gastrointestinal toxicity were not at an increased risk of late grade ≥2 gastrointestinal toxicity (odds ratio 1.3; P = 0.55). CONCLUSIONS: Factors of importance for acute and late gastrointestinal toxicity were not the same. Bowel cavity V30Gy is a good metric to use for the prediction of acute gastrointestinal toxicity, but the results of our study indicate that individual large and small bowel loops need to be contoured for better prediction of late gastrointestinal toxicity. The role of the large bowel as an important organ at risk for late gastrointestinal toxicity merits further research.

Mentorship during undergraduate surgical training: comparing perceptions of medical students and faculty at two institutions in South Africa and Sweden.

BACKGROUND: Having a mentor during undergraduate surgical training has been shown to positively influence medical students by increasing interest in surgery, improving confidence, and assisting in career planning. This study aimed to evaluate and compare medical student and faculty perceptions of mentorship during undergraduate surgical training and compare results between two teaching institutions in South Africa and Sweden. METHODS: An electronic, online questionnaire was anonymously distributed to medical students and general surgical faculty at the University of Cape Town (UCT), South Africa, and Karolinska Institutet (KI), Stockholm, Sweden. The questionnaire consisted of multiple choice, true or false, and five-point Likert scale questions, exploring perceptions of mentorship and role models, as well as rating the most important mentor characteristics. RESULTS: Approximately one third (34.2%) of students stated they had a mentor during their surgical training, with significant differences found between student cohorts (p < 0.001). The 'registrar' was most commonly reported as the best role model for medical students by faculty from both UCT (50.0%) and KI (69.4%), as well as UCT students (36.6%). Students rated the following mentor qualities significantly higher compared to faculty: student encouragement (p = 0.037), adequate supervision (p = 0.007), setting of fair expectations (p = 0.002), and teaching skills (p = 0.010). CONCLUSION: With significant differences existing in the perceptions of medical students and faculty regarding mentorship and role models during undergraduate surgical training in both South African and Swedish institutions, reconciling and harmonising these differences will be crucial in fostering constructive mentoring relationships.

Autumn destabilization of deep porewater CO2 store in a northern peatland driven by turbulent diffusion.

The deep porewater of northern peatlands stores large amounts of carbon dioxide (CO2). This store is viewed as a stable feature in the peatland CO2 cycle. Here, we report large and rapid fluctuations in deep porewater CO2 concentration recurring every autumn over four consecutive years in a boreal peatland. Estimates of the vertical diffusion of heat indicate that CO2 diffusion occurs at the turbulent rather than molecular rate. The weakening of porewater thermal stratification in autumn likely increases turbulent diffusion, thus fostering a rapid diffusion of deeper porewater CO2 towards the surface where net losses occur. This phenomenon periodically decreases the peat porewater CO2 store by between 29 and 90 g C m-2 throughout autumn, which is comparable to the peatland's annual C-sink. Our results establish the need to consider the role of turbulent diffusion in regularly destabilizing the CO2 store in peat porewater.

Incidence, detection and outcome of differentiated thyroid cancer in Western Sweden.

BACKGROUND: It is unclear whether the increasing incidence of thyroid cancer (TC) due to increased diagnosis of small and indolent tumours might mask a real increase of clinically significant cancers. The aim of this study was to correlate surgery, pathology and outcome data of individual patients to the mode of primary detection (palpation, by imaging or incidental) to assess if TC incidence has increased. METHODS: The Swedish Cancer Registry identified all patients with TC in Västra Götaland County representing approximately 1.6 million inhabitants. Clinical information was retrieved from medical records of patient cohorts from three study intervals (2001-2002, 2006-2007 and 2011-2014) comprising 60 per cent of all TC patients. Data were also obtained from the NORDCAN registry to compare of TC incidence with other Nordic countries. RESULTS: Between 2001 and 2014, the annualized standard incidence rate/100 000 population (ASR) of TC increased from 3.14 to 10.71 in women and from 1.12 to 3.77 in men. This was higher than the mean incidence for Sweden but similar to that in Norway and Finland. Differentiated TC (DTC) increased more than threefold. The majority of tumours (64 per cent) were detected by palpation. Larger tumours (10-20, 21-40 and greater than 40 mm) increased as much as microcarcinomas (less than 10 mm). Only 5 per cent of the tumours were detected by imaging. All disease-specific deaths (8.5 per cent of DTC in the first two cohorts) and most patients with recurrent or persistent disease (6.6 per cent of DTC cases) were diagnosed due to tumour-related symptoms. CONCLUSION: DTC in Western Sweden gradually increased between 2001 and 2014. The majority of tumours were detected by palpation suggesting a real increase in the incidence of clinically significant thyroid malignancies.

Patient-reported outcomes after oesophagectomy in the multicentre LASER study.

BACKGROUND: Data on the long-term symptom burden in patients surviving oesophageal cancer surgery are scarce. The aim of this study was to identify the most prevalent symptoms and their interactions with health-related quality of life. METHODS: This was a cross-sectional cohort study of patients who underwent oesophageal cancer surgery in 20 European centres between 2010 and 2016. Patients had to be disease-free for at least 1 year. They were asked to complete a 28-symptom questionnaire at a single time point, at least 1 year after surgery. Principal component analysis was used to assess for clustering and association of symptoms. Risk factors associated with the development of severe symptoms were identified by multivariable logistic regression models. RESULTS: Of 1081 invited patients, 876 (81.0 per cent) responded. Symptoms in the preceding 6 months associated with previous surgery were experienced by 586 patients (66.9 per cent). The most common severe symptoms included reduced energy or activity tolerance (30.7 per cent), feeling of early fullness after eating (30.0 per cent), tiredness (28.7 per cent), and heartburn/acid or bile regurgitation (19.6 per cent). Clustering analysis showed that symptoms clustered into six domains: lethargy, musculoskeletal pain, dumping, lower gastrointestinal symptoms, regurgitation/reflux, and swallowing/conduit problems; the latter two were the most closely associated. Surgical approach, neoadjuvant therapy, patient age, and sex were factors associated with severe symptoms. CONCLUSION: A long-term symptom burden is common after oesophageal cancer surgery.

Executive functioning in psychiatric patients with deliberate self-harm, as compared with a psychiatric and a healthy comparison group.

Introduction: Deliberate self-harm (DSH) is a common symptom in psychiatric disorders. It is a cross-diagnostic symptom, although it has mainly been associated with borderline personality disorder (BPD). Research has suggested an association between DSH and deficits in executive functioning. The main aim of the current study was to assess three specific aspects of executive functioning (EF) (working memory, inhibition and cognitive flexibility) among psychiatric patients with DSH, compared to a clinical and a healthy comparison group.Methods: Thirty psychiatric patients with DSH, 29 psychiatric patients without DSH and 29 healthy individuals were assessed with regard to psychiatric illness, self-harming behavior, EF, general cognitive functioning level and measures of psychopathology. The results were analyzed by means of ANOVA, regression analysis, Chi-square, and correlation analysis.Results: The patients with DSH showed deficits in cognitive flexibility and inhibition as compared to healthy individuals. In addition, the patients with DSH had greater deficits in cognitive flexibility than the patients without DSH; this effect was independent of concurrent severity of depressive symptoms but not independent of borderline symptomatology.Conclusion: Psychiatric patients with DSH may have deficits in cognitive flexibility as compared to both the healthy and clinical comparison groups. The results partly differ from previous related studies in the field. It is unclear to which extent the deficits in cognitive flexibility are due to other factors. More research is needed to understand the implications of such deficits, and if the results could be used for adapting treatment services and strategies. Future studies should include more similar comparison groups.

Low risk of transmission of pathogenic bacteria between children and the assistance dog during animal-assisted therapy if strict rules are followed.

This study explored the bacterial transmission between patients and dogs during dog-assisted therapy (DAT). Twenty children (55% girls) with a median age of 7 years (range 3-17 years) were included. Two dogs assisted and the conditions were more restricted hygienically with dog 2. Samples from child and dog were collected and cultured before and after each DAT visit. The results showed that dog 1 transmitted bacteria repeatedly to the children. No bacteria were transmitted with dog 2. In conclusion, exchange of bacteria can occur between dog and child during DAT, but it can be reduced by simple infection control measures.

Mortality after surgery for primary hyperparathyroidism: results from a nationwide cohort.

BACKGROUND: Contemporary patients with primary hyperparathyroidism are often diagnosed with mildly raised serum calcium levels. Previous studies have reported increased mortality in patients with primary hyperparathyroidism. This retrospective cohort study aimed to examine whether contemporary patients operated for primary hyperparathyroidism have higher mortality than the general population, and whether mortality in these patients is associated with serum calcium concentration, adenoma weight or multiglandular disease. METHODS: Patients from a Swedish national cohort consisting of patients registered in the Scandinavian Quality Register for Thyroid, Parathyroid, and Adrenal Surgery 2003-2013, were matched with population controls. The National Patient Register, the Swedish Cause of Death Register, and socioeconomic data were cross-linked. End of follow-up was 10 years after surgery, 31 December 2015, or emigration. Mortality was analysed by standardized mortality ratio, Kaplan-Meier survival estimates, and univariable and multivariable Cox regression. Multiple imputation by chained equations was performed on missing data. RESULTS: After exclusions, there were 5009 patients with primary hyperparathyroidism and 14 983 controls. Multivariable Cox regression analysis adjusted for age, sex, Charlson Co-morbidity Index, marital status, level of education, disposable income, and period of surgery showed lower mortality in patients than controls (hazard ratio (HR) 0.83, 95 per cent c.i. 0.75 to 0.92). In univariable Cox regression of mortality in patients, serum calcium concentration (mmoles per litre) was associated with mortality (HR 2.20, 1.53 to 3.16). This association remained in multivariable Cox regression after multiple imputation (HR 1.79, 1.19 to 2.70). CONCLUSION: Mortality was not increased in patients operated for primary hyperparathyroidism compared with controls in a contemporary setting. Preoperative serum calcium concentration might, however, influence survival.