A prospective, randomized assessment of a novel, local antibiotic releasing platform for the prevention of superficial and deep surgical site infections

BACKGROUND

Despite significant advances in infection control guidelines and practices, surgical site infections (SSIs) remain a substantial cause of morbidity, prolonged hospitalization, and mortality among patients having both elective and emergent surgeries. D-PLEX₁₀₀ is a novel, antibiotic-eluting polymer-lipid matrix that supplies a high, local concentration of doxycycline for the prevention of superficial and deep SSIs. The aim of our study was to evaluate the safety and efficacy of D-PLEX in addition to standard of care (SOC) in preventing superficial and deep surgical site infections for patients undergoing elective colorectal surgery.

METHODS

From October 10, 2018 to October 6, 2019, as part of a Phase 2 clinical trial, we randomly assigned 202 patients who had scheduled elective colorectal surgery to receive either standard of care SSI prophylaxis or D-PLEX₁₀₀ in addition to standard of care. The primary objective was to assess the efficacy of D-PLEX₁₀₀ in superficial and deep SSI reduction, as measured by the incidence of SSIs within 30 days, as adjudicated by both an individual assessor and a three-person endpoint adjudication committee, all of whom were blinded to study-group assignments. Safety was assessed by the stratification and incidence of treatment-emergent adverse events.

RESULTS

One hundred and seventy-nine patients were evaluated in the per protocol population, 88 in the intervention arm [51 males, 37 females, median age (64.0 range: 19-92) years] and 91 in the control arm [57 males, 34 females, median age 64.5 (range: 21-88) years]. The SSI rate within 30 day post-index surgery revealed a 64% relative risk reduction in SSI rate in the D-PLEX₁₀₀ plus standard of care (SOC) group [n = 7/88 (8%)] vs SOC alone [n = 20/91 (22%)]; p = 0.0115. There was no significant difference in treatment-emergent adverse events.

CONCLUSIONS

D-PLEX₁₀₀ application leads to a statistically significant reduction in superficial and deep surgical site infections in this colorectal clinical model without any associated increase in adverse events.

Timing of colostomy reversal following Hartmann's procedure for perforated diverticulitis

AIM

Hartmann's procedure is the surgical treatment of choice for perforated acute diverticulitis. Hartmann's reversal (HR) that is performed at a later stage may be challenging. The optimal timing for HR is still a subject for controversy. The aim of this study is to assess whether the timing of HR affects surgical outcome.

PATIENTS AND METHODS

A retrospective-cohort multi-center study was conducted, including all patients who underwent HR for acute diverticulitis from January 2004 to June 2015 in 5 medical centers. Patient data included demographics, surgical data and post-operative outcome.

RESULTS

One hundred and twenty-two patients were included in the database. Median time from Hartmann's procedure to reversal was 182.7 days, with the majority of patients (76 patients, 62.2%) operated 60 to 180 days from the Hartmann's procedure. Fifty-seven patients (46.7%) had post-operative complications, most commonly wound infections (27 patients, 22.1%). Receiver operating characteristic (ROC) curve and a propensity score match analysis (P=0.43) correlating between days to HR from the index procedure showed no specific cut-off point regarding post-operative complications (P=0.16), Major (Clavien-Dindo score of 3 or more) complications (P=0.19), Minor (Clavien Dindo 1-2) and no complications (P=0.14). Median length of stay was 10.9 days (range 3-90) and Pearson correlation failed to demonstrate a correlation between timing of surgical intervention and length of stay (P=0.4).

CONCLUSION

Hartmann's Reversal is a complex surgical procedure associated with high rates of complications. In our series, timing of surgery did not affect surgical complications rate or severity or the length of hospital stay.

Three-dimensional endoanal ultrasonography of external anal sphincter defects in patients with faecal incontinence: correlation with symptoms and manometry

AIM

Anal sphincter anatomy on two-dimensional endoanal -ultrasonography (EUS) does not always correlate with the clinical data. The purpose of this study was to determine whether three-dimensional (3D) measurements yield a better correlation.

METHOD

The study group included consecutive patients who underwent 3D EUS for faecal incontinence over a 2-year period. The medical charts were reviewed for Cleveland Clinic Foundation Fecal Incontinence (CCF-FI) score and manometric pressures. Endoanal ultrasonographic images were reviewed for the presence of an external anal sphincter (EAS) defect and its extent, as determined by the radial angle, length in the sagittal plane and percentage volume deficit. Correlational analyses were performed between the clinical and imaging data.

RESULTS

Sixty-one patients of median age 53 years (range 15-82) were evaluated. Thirty-two patients had either a complete (17) or partial (15) EAS defect, and 29 patients had an intact sphincter. The CCF-FI scores were similar in patients with and without an EAS defect (12.5 ± 5.6 and 11.4 ± 5.5, respectively). The intact-sphincter group had a significantly greater EAS length (3 ± 0.4 vs 2 ± 0.62 cm, P = 0.02) and higher mean maximal squeeze pressure (MMSP; 99.7 ± 52.6 vs 66.9 ± 52.9 mmHg, P = 0.009). There were no statistically significant correlations between MMSP, CCF-FI score and EAS status on 3D EUS. Mean percentage volume of the defect was similar in patients with complete and partial tears (14.5 ± 5.5 and 17.5 ± 7.2%, P = 0.25) and showed no correlation with physiological tests or symptom scores.

CONCLUSION

Improvements in external anal sphincter imaging have not yielded a better association with the clinical findings. The lack of clinical differences between patients with different EAS tears may reflect their similar volumetric defects.

Early prediction of pathological complete response (pCR) of rectal cancer after 1 week of preoperative radiochemotherapy (RCT) using positron emission computererized tomography (PET-CT) imaging

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Background: Preoperative radiochemotherapy (RCT) is the standard treatment of locally advanced rectal cancer (LARC), obtaining pathological complete response (pCR) in 15%-30% of cases. Post-RCT reduction of 18F-fluorodeoxyglucose (FDG) uptake within the tumor compared with the baseline, i.e. the tumor's metabolic response, correlates with pCR. However, an earlier prediction of pCR could enable tailored modifications of the treatment. We hence evaluated the correlation between the metabolic response after only one week of RCT for LARC and the actual pCR at the post-RCT surgery.

Methods: Patients (pts) were eligible for this prospective study if they had LARC, defined as T3-4NX or TxN+ tumors by pre-treatment PET-CT and endoscopic ultrasound. Pts received standard RCT regimen, consisting of 50.4Gy radiotherapy concurrently with a fluoropyrimidine-based chemotherapy, followed by surgery. Pts underwent baseline FDG-PET-CT imaging within 2 weeks prior to the initiation of RCT and a second one on day 8 of RCT. Maximum standardized uptake value (SUV-max) was measured in both scans and changes in FDG- uptake were recorded. Man-Whitney test was used to evaluate differences in the SUV-max between baseline and day 8 in pts obtaining pCR and those who did not.

Results: Twenty pts participated in the study. Half were males and the median age was 64 years. Ten pts had T3N0 tumors and 10 had T3N+ disease. Radical surgery was done in 19 pts and local excision in one. Considering the entire group, there was a borderline-significant difference between the metabolic response of pts with pCR and those without pCR (Chi-square = 3.429, p = 0.064). Yet, the changes in FGD-uptake were able to identify pts who achieved pCR and those who did not: only pts with a decrease of more than 33% in SUV-max had pCR while none of the pts who had less than 8.9% decrease in SUV-max had pCR.

Conclusions: A decrease in SUV-max between baseline-PET-CT scans and scans done after only one week of RCT for LARC may be able to predict the achievement of pCR in the post-RCT surgical specimen. Validation in a larger independent cohort is planned.

No significant financial relationships to disclose.

The role of postoperative PET-CT in the evaluation of patients with high-risk stage III colorectal cancer (CRC)

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Background: Routine PET-CT evaluation is still not indicated for stage III CRC patients; however accumulating data suggest that it may modify these patients' staging and treatment. We hence evaluated the role of PET-CT in high risk stage III CRC patients and to characterize positive predictors.

Methods: Retrospective chart review of stage III CRC patients who underwent PET-CT for being at high risk for systemic disease attributable to: early T stage (T < 3), grade > 3, < 12 lymph-nodes examined, > 3 involved lymph-nodes, elevated postoperative CEA and/or CA-19.9. The demographic and clinicopathological characteristics of patients found to have metastatic disease were compared to those who were negative.

Results: Seventy-three patients (33 males [45%], median age 67 years [range: 29-88 years]) were included. Pathologic FDG-uptake was observed in 33 (45%) patients. Of them, 16 (22%) were upstaged with altered treatment protocol, 13 (18%) required further work-up and 4 (5%) were found to have post operative changes. Elevated post-operative CEA and CA-19.9 levels correlated with positive PET-CT (p = 0.002 and p = 0.015, respectively). None of the other examined parameters differed between the groups. With a median follow-up of 26 months (range:1-63 months), overall survival was 88% in patients with positive PET-CT and 92% in patients with negative PET-CT. Eight patients in the positive group were disease free following metastectomy, five were alive with disease, two patients died of disease and one patient died of other cause.

Conclusions: Selective postoperative PET-CT influenced staging/therapy in 22% of high risk stage III CRC patients. Postoperative CEA and CA-19.9 levels may play a role in selecting eligible patients. Failure to identify other parameters may be related to the preexisting selection bias and the small cohort.

No significant financial relationships to disclose.

High incidence of non-upper aerodigestive primary tumors in patients with esophageal cancer

Earlier reports have described an association between esophageal cancer (EC) and high incidence of other primary tumors (OPTs) of the upper aerodigestive tract and breast cancer. We evaluated the incidence of non-upper aerodigestive OPTs among Israeli EC patients; 2328 EC patients were retrieved from the Israeli National Cancer Registry between 1980 and 2004. The relative risk of OPTs for EC patients was measured using standardized incidence ratio (SIR). Two cohorts, Israeli National Cancer Registry registered colorectal cancer (CRC) patients and the general Israeli population, were used for reference; 297 EC patients (12.7%) had OPTs, including breast (18.9%), CRC (16.2%), prostate (8.8%), and bladder (8.4%) cancers. Upper aerodigestive OPTs were less common. Most OPTs were identified before (74.4%) or simultaneously with (13.8%) EC diagnosis. The median time interval between OPTs diagnoses and EC development was 6.0 years. The incidence of OPTs was significantly higher among EC patients compared with CRC patients (SIR: 2.05, P < 0.01) or the general Israeli population (SIR: 3.90, 95% CI: 3.46-4.34, P < 0.01) regardless of gender or tumor histology. Patients with EC have high incidence of non-upper aerodigestive malignancies. Unlike previous reports, the distribution of OPTs in EC seems to represent the relative incidences of these cancers in the western populations.

Sentinel-lymph-node biopsy (SLNB) for melanoma is not complication-free

BACKGROUND AND AIM

Sentinel lymph node biopsy (SLNB) is reportedly associated with insignificant morbidity. The study aims at documenting SLNB-related complications and identifying possible risk factors.

METHOD

Data of all melanoma patients who underwent SLNB in our medical center (1994-2002) were analysed. Procedure-related complications were recorded.

RESULTS

Three hundred and nine lymphatic basins of 250 patients were explored for SLNB. Overall complication rate was 20%. Sensory morbidity was significantly associated with axillary SLNB (p=0.04) and was more prevalent in younger patients. The use of blue dye alone or combined with a hand-held gamma probe had no statistically significant impact on the identification rate. There were six false-negatives (2.3%), for an overall false-negative rate of 18%. A positive sentinel node was significantly associated with shortened overall survival (p=0.04).

CONCLUSION

Wound complications are more frequent than usually reported. Sensory morbidity occurs mostly in the axilla. Neck SLNB is associated with the highest rate of identification failure. Patient age, basin location, and number of excised nodes may serve as prognostic factors of morbidity.

Applicability of the sentinel node technique to Merkel cell carcinoma

BACKGROUND

Merkel cell carcinoma (MCC) resembles malignant melanoma in several ways. Both are cutaneous lesions of the same embryonic origin. Both have an unpredictable biologic behavior, early regional lymph node involvement, early distant metastases, and high recurrence rate.

OBJECTIVE

To apply the sentinel node technique described for melanoma to MCC in light of the common biologic features of these two tumors.

METHODS

Preoperative lymphoscintigraphy, intraoperative lymphatic mapping, and sentinel node biopsy and frozen section histology were performed to guide the surgical treatment of three patients with MCC.

RESULTS

Application of this approach in patients with MCC is feasible, reproducible, and seems reliable.

CONCLUSION

The use of the sentinel node technique for MCC will reduce the number of unnecessary lymphadenectomies, will enable identification of microscopic metastases to lymph nodes, and will improve the stratification and accrual of patients into adjuvant treatment protocols. It may even lead to a survival benefit.

Sentinel-node guided lymph-node dissection for merkel cell carcinoma

Merkel cell carcinoma is an aggressive neuroendocrine skin tumour. Treatment is still debatable. Merkel cell carcinoma resembles malignant melanoma in its cutaneous presentation and its embryonic origin; both have unpredictable biological behaviour, early regional lymph node involvement, early distant metastases and a high recurrence rate. In light of these common features, we used pre-operative lymphoscintigraphy, intraoperative lymph-node mapping and sentinel-node biopsy-a well-described technique for the treatment of melanoma-in a 60-year-old man with Merkel cell carcinoma in the right buttock. Following frozen section identification of a metastatic first-order sentinel node, radical right groin dissection was performed. All the other lymph nodes in this basin proved to be disease-free, including the second-order sentinel node and Cloquet node. The patient is now being treated with adjuvant chemotherapy and radiotherapy. This case shows that sentinel-node guided dissection is applicable to Merkel cell carcinoma.