Contribution of Prior, Multiple-, and Repetitive Surgeries to the Risk of Surgical Site Infections in the Netherlands.

OBJECTIVE Surveillance is an important strategy to reduce the incidence of surgical site infections (SSIs). We investigated whether prior, multiple-, or repetitive surgeries are risk factors for SSI and whether they should be preserved in the protocol of the Dutch national SSI surveillance network. METHODS Dutch national SSI surveillance data 2012-2015 were selected, including 34 commonly performed procedures from 8 major surgical specialties. Definitions of SSIs followed international standardized criteria. We used multivariable multilevel logistic regression techniques to evaluate whether prior, multiple-, or repetitive procedure(s) are risk factors for SSIs. We considered surgeries clustered within partnerships of medical specialists and within hospitals (random effects) and different baseline risks between surgical specialties (fixed effects). Several patient and surgical characteristics were considered possible confounders and were included where necessary. We performed analyses for superficial and deep SSIs combined as well as separately. RESULTS In total, 115,943 surgeries were reported by 85 hospitals; among them, 2,960 (2.6%) resulted in SSIs (49.3% deep SSIs). The odds ratio (OR) for having prior surgery was 0.94 (95% confidence interval [CI], 0.74-1.20); the OR for repetitive surgery was 2.39 (95% CI, 2.06-2.77); and the OR for multiple surgeries was1.27 (95% CI, 1.07-1.51). The latter effect was mainly caused by prolonged duration of surgery. CONCLUSIONS Multiple- and repetitive surgeries significantly increased the risk of an SSI, whereas prior surgery did not. Therefore, prior surgery is not an essential data item to include in the national SSI surveillance network. The increased risk of SSIs for multiple surgeries was mainly caused by prolonged duration of surgery, therefore, it may be sufficient to report only duration of surgery to the surveillance network, instead of both (the variables duration of surgery and multiple surgeries). Infect Control Hosp Epidemiol 2017;38:1298-1305.

Consequences of additional use of PET information for target volume delineation and radiotherapy dose distribution for esophageal cancer.

BACKGROUND AND PURPOSE: To determine the consequences of target volume (TV) modifications, based on the additional use of PET information, on radiation planning, assuming PET/CT-imaging represents the true extent of the tumour. MATERIALS AND METHODS: For 21 patients with esophageal cancer, two separate TV's were retrospectively defined based on CT (CT-TV) and co-registered PET/CT images (PET/CT-TV). Two 3D-CRT plans (prescribed dose 50.4 Gy) were constructed to cover the corresponding TV's. Subsequently, these plans were compared for target coverage, normal tissue dose-volume histograms and the corresponding normal tissue complication probability (NTCP) values. RESULTS: The addition of PET led to the modification of CT-TV with at least 10% in 12 of 21 patients (57%) (reduction in 9, enlargement in 3). PET/CT-TV was inadequately covered by the CT-based treatment plan in 8 patients (36%). Treatment plan modifications resulted in significant changes (p<0.05) in dose distributions to heart and lungs. Corresponding changes in NTCP values ranged from -3% to +2% for radiation pneumonitis and from -0.2% to +1.2% for cardiac mortality. CONCLUSIONS: This study demonstrated that TV's based on CT might exclude PET-avid disease. Consequences are under dosing and thereby possibly ineffective treatment. Moreover, the addition of PET in radiation planning might result in clinical important changes in NTCP.

Better assessment of nodal metastases by PET/CT fusion compared to side-by-side PET/CT in oesophageal cancer.

BACKGROUND: Recently, positron emission tomography/computed tomography (PET/CT) has been introduced in the staging of oesophageal cancer. The impact of PET/CT fusion in comparison with side-by-side PET/CT in these tumours, was analyzed. PATIENTS AND METHODS: In 61 patients, 18-F-fluorodeoxyglucose (FDG)-PET and multidetector (md)-CT were performed within a two week interval. Software-fusion of md-CT and FDG-PET was correlated with side-by-side FDG-PET/CT reading by two independent investigators. The gold standard was the pathological outcome or clinical evidence of progression during the first year of follow-up. RESULTS: In 18 patients (18/61; 30%), nodal staging improved with software-fusion. The number of nodal metastases increased in five patients and decreased in four patients, leading to up-staging in one patient (2%) and down-staging in three patients (5%). In nine cases (15%), certainty and localization of metastases improved. However, the number of distant metastases did not change and software-fusion did not have an influence on resectability. CONCLUSION: PET/CT fusion substantially improves detection and localization of nodal metastases and may have an impact on locoregional treatment options.

Current relevance of cervical ultrasonography in staging cancer of the esophagus and gastroesophageal junction.

PURPOSE: To evaluate the value of external ultrasonography (US) of the neck in current dedicated preoperative staging of patients with cancer of the esophagus and gastroesophageal junction (GEJ). MATERIALS AND METHODS: We analyzed 180 consecutive patients (154 men, 26 women, and mean age 63 (38-84) years) without palpable cervical lymphadenopathy, treated between January 2001 and March 2006. Suspicious lesions were confirmed by cytological examination. All first 125 consecutive patients (group A) were staged by standard endoscopic ultrasonography (EUS), multidetector computed tomography (md-CT), positron emission tomography with (18)F-fluorodeoxyglucose (FDG-PET) and external US. The other 55 patients (group B) were prospectively staged according to a revised protocol consisting of routine EUS and md-CT, while PET was only performed in subjects with T3-T4 and/or N1 disease and external US solely on indication. RESULTS: Cervical metastases were found in seven patients from group A (6%) and in five from group B (9%). Twenty percent (4/20) of the tumors above the carina and 5% (8/160) of the distal tumors presented with cervical metastases. All were diagnosed as T3 and T4 tumors on EUS. Eleven of these metastases were detected by external US and nine on md-CT. All nodal metastases were detected by the combination of PET and md-CT. No cervical metastases were missed by the diagnostic algorithm in group B. CONCLUSION: In present staging procedures for esophageal cancer, routine external US seems to have no additional value in detecting cervical metastases. It is still indicated to obtain cytological proof of suspected cervical lesions.