Label-free multiphoton microscopy enables histopathological assessment of colorectal liver metastases and supports automated classification of neoplastic tissue.

As the state of resection margins is an important prognostic factor after extirpation of colorectal liver metastases, surgeons aim to obtain negative margins, sometimes elaborated by resections of the positive resection plane after intraoperative frozen sections. However, this is time consuming and results sometimes remain unclear during surgery. Label-free multimodal multiphoton microscopy (MPM) is an optical technique that retrieves morpho-chemical information avoiding all staining and that can potentially be performed in real-time. Here, we investigated colorectal liver metastases and hepatic tissue using a combination of three endogenous nonlinear signals, namely: coherent anti-Stokes Raman scattering (CARS) to visualize lipids, two-photon excited fluorescence (TPEF) to visualize cellular patterns, and second harmonic generation (SHG) to visualize collagen fibers. We acquired and analyzed over forty thousand MPM images of metastatic and normal liver tissue of 106 patients. The morphological information with biochemical specificity produced by MPM allowed discriminating normal liver from metastatic tissue and discerning the tumor borders on cryosections as well as formalin-fixed bulk tissue. Furthermore, automated tissue type classification with a correct rate close to 95% was possible using a simple approach based on discriminant analysis of texture parameters. Therefore, MPM has the potential to increase the precision of resection margins in hepatic surgery of metastases without prolonging surgical intervention.

Macroscopic, histologic, and clinical assessment of acute graft-versus-host disease of the upper gastrointestinal tract within 6 weeks after allogeneic hematopoietic cell transplantation.

Acute graft-versus-host-disease (aGVHD) is the main cause of morbidity and nonrelapse mortality (NRM) following allogeneic hematopoietic cell transplantation (alloHCT). Nausea, vomiting, and anorexia after alloHCT can be early signs of aGVHD of the gastrointestinal tract (GIT) but may also reflect lasting mucosal damage or side effects of drugs. If upper GIT aGVHD is suspected, upper endoscopic evaluation and histological examination are crucial. Still, the interpretation of clinical symptoms, macroscopical alterations, and histological findings can be challenging. Therefore, we conducted a retrospective analysis on single-center data from 174 patients with suspected aGVHD of the upper GIT who underwent upper endoscopy within the first 6 weeks after alloHCT, to study the distribution of aGVHD-related histological findings in relation to clinical symptoms and macroscopic findings and to correlate the severity of changes with data on relapse and NRM. Our data suggest that biopsies of the duodenum reveal the severity of upper GIT aGVHD most accurately. While the histological grading correlated weakly with the severity of macroscopic changes, we found a tight correlation between histological and clinical grades of upper GIT aGVHD (p < 0.001). Although correlation of histological grading of upper GIT aGVHD with the risk for NRM missed statistical significance (HR 1.53, Lerner ≥1° versus <1º, p = 0.13), overall clinical aGVHD severity correlated with NRM (HR 4.3, IIIº-IVº versus 0-Iº, p < 0.01). In conclusion, biopsies from the duodenum are most sensitive in excluding aGVHD in patients with normal macroscopic findings at esophagogastroduodenoscopy. Clinical grading of aGVHD predicts NRM better than histological grading.

Guidelines for time-to-event end-point definitions in trials for pancreatic cancer. Results of the DATECAN initiative (Definition for the Assessment of Time-to-event End-points in CANcer trials).

BACKGROUND: Using potential surrogate end-points for overall survival (OS) such as Disease-Free- (DFS) or Progression-Free Survival (PFS) is increasingly common in randomised controlled trials (RCTs). However, end-points are too often imprecisely defined which largely contributes to a lack of homogeneity across trials, hampering comparison between them. The aim of the DATECAN (Definition for the Assessment of Time-to-event End-points in CANcer trials)-Pancreas project is to provide guidelines for standardised definition of time-to-event end-points in RCTs for pancreatic cancer. METHODS: Time-to-event end-points currently used were identified from a literature review of pancreatic RCT trials (2006-2009). Academic research groups were contacted for participation in order to select clinicians and methodologists to participate in the pilot and scoring groups (>30 experts). A consensus was built after 2 rounds of the modified Delphi formal consensus approach with the Rand scoring methodology (range: 1-9). RESULTS: For pancreatic cancer, 14 time to event end-points and 25 distinct event types applied to two settings (detectable disease and/or no detectable disease) were considered relevant and included in the questionnaire sent to 52 selected experts. Thirty experts answered both scoring rounds. A total of 204 events distributed over the 14 end-points were scored. After the first round, consensus was reached for 25 items; after the second consensus was reached for 156 items; and after the face-to-face meeting for 203 items. CONCLUSION: The formal consensus approach reached the elaboration of guidelines for standardised definitions of time-to-event end-points allowing cross-comparison of RCTs in pancreatic cancer.

Local staging of rectal cancer: assessment with double-contrast multislice computed tomography and transrectal ultrasound.

OBJECTIVE: The aim of this study was to evaluate the accuracy of multislice computed tomography (MSCT) with double-contrast technique and transrectal ultrasound (TRUS) in staging of rectal carcinoma compared with histopathological confirmation. METHODS: In a prospective study of 92 patients with rectal carcinoma, preoperative MSCT with negative rectal contrast (methylcellulose) and intravenous contrast was performed. Reconstructions in 3 planes were analyzed in a cine mode in picture archiving and communication (PAC) system. Analysis of rectal wall infiltration was performed preoperatively according to a modified tumor, nodes, metastases (TNM)-classification system (< or =T2/T3/T4, N0/N+, UICC/UICC I > I). MSCT imaging findings were compared with the results of TRUS and histopathology in all patients. RESULTS: With interactive multiplanar image viewing, the results of MSCT of depth of rectal wall invasion (T-staging) were as follows: sensitivity, specificity, positive and negative predictive values, and accuracy rate were 85%, 87%, 88%, 84%, and 86% (54/63 patients) compared with 59%, 63%, 72%, 48%, and 60% (38/63 patients), respectively, for TRUS staging in the same patients. The sensitivity, specificity, positive and negative predictive values, and accuracy rate of MSCT for perirectal nodes evaluation was 75%, 85%, 75%, 85%, and 81% (51/63 patients) compared with 55%, 71%, 50%, 74%, and 65% (41/63 patients), respectively, for TRUS in detecting metastatic lymph nodes. CONCLUSIONS: Preoperative double-contrast MSCT accurately indicates the exact depth of tumor infiltration and improves lymph node staging. The new technical innovations of MSCT provide superior information for preoperative staging of rectal cancer and may compete with TRUS as the standard preoperative diagnostic method.