We report a new image processing technique for the structured illumination microscopy designed to work with low signals, with the goal of reducing photobleaching and phototoxicity of the sample. Using a pre-filtering process to estimate experimental parameters and total variation as a constraint to reconstruct, we obtain two orders of magnitude of exposure reduction while maintaining the resolution improvement and image quality compared to a standard structured illumination microscopy. The algorithm is validated on both fixed and live cell data with results confirming that we can image more than 15x more time points compared to the standard technique.

A wait-and-see policy might be considered instead of surgery for rectal cancer patients with no residual tumor or involved lymph nodes on imaging or endoscopy after neoadjuvant chemoradiotherapy (clinical complete response, cCR). In this cohort study, we compared the oncologic outcomes of rectal cancer patients with a cCR who were managed according to a wait-and-see policy (observation group) or with surgery (surgery group). In the observation group, follow-up was performed every 3 months for the first year and consisted of MRI, endoscopy with biopsy, computed tomography and transrectal ultrasonography. In the surgery group, patients received radical surgery. Long-term oncologic outcomes were estimated using Kaplan-Meier curves. Thirty patients were enrolled in the observation group (median follow-up, 60 months; range, 18-100 months), and 92 patients were enrolled in the surgery group (median follow-up, 58 months; range, 18-109 months). The 5-year disease free survival and overall survival rates were similar in the two groups: 90.0% vs. 94.3% (P = 0.932) and 100.0% vs. 95.6% (P = 0.912), respectively. We conclude that for rectal cancer patients with a cCR after neoadjuvant chemoradiotherapy, a wait-and-see policy with strict selection criteria, follow-up and salvage treatments achieves outcomes at least as good as radical surgery. Additionally, we declare that the pCR (pathologic complete regression) and non-pCR subgroups of patients with a cCR have similar long-term failure (local recurrence and/or distant metastasis) rate.

We investigated the possibility of counting tumor deposits (TDs) as positive lymph nodes (pLNs) in the pN category and evaluated its prognostic value for colorectal cancer (CRC) patients. A new pN category (npN category) was calculated using the numbers of pLNs plus TDs. The npN category included 4 tiers: npN1a (1 tumor node), npN1b (2-3 tumor nodes), npN2a (4-6 tumor nodes), and npN2b (≥7 tumor nodes). We identified 4,121 locally advanced CRC patients, including 717 (11.02%) cases with TDs. Univariate and multivariate analyses were performed to evaluate the disease-free and overall survival (DFS and OS) for npN and pN categories. Multivariate analysis showed that the npN and pN categories were both independent prognostic factors for DFS (HR 1.614, 95% CI 1.541 to 1.673; HR 1.604, 95% CI 1.533 to 1.679) and OS (HR 1.633, 95% CI 1.550 to 1.720; HR 1.470, 95% CI 1.410 to 1.532). However, the npN category was superior to the pN category by Harrell's C statistic. We conclude that it is thus feasible to consider TDs as positive lymph nodes in the pN category when evaluating the prognoses of CRC patients, and the npN category is potentially superior to the TNM (7th edition) pN category for predicting DFS and OS among advanced CRC patients.

Objective To investigate the diagnostic status of colorectal cancer (CRC) and the influence of early diagnosis and cancer stage in a tertiary care hospital in China. Methods Face‐to‐face interviews were conducted in 364 consecutive CRC patients who had never participated in CRC screening. Initial symptoms, diagnosis and treatment delay were determined using a questionnaire. Factors influencing diagnostic status were analyzed using univariate analysis and logistic regression model. Results A total of 307 patients were enrolled, in which 128 were with colon cancer and 179 with rectal cancer. The duration of diagnosis delay was significant longer than that of treatment delay. Unlike rectal cancer, colon cancer was likely to be treated at an advanced stage with a short interval between symptom onset and treatment. Colon cancer patients with a history of biliary tract or gallbladder stones, aged ≥ 50 years and with abdominal mass or intestinal obstruction as the initial symptom were diagnosed and treated much earlier. In rectal cancer, women and non‐smokers were diagnosed and treated quickly. Factors correlated with early cancer stage were found in colon cancer, including bloody stool as the initial symptom (OR = 2.63, 95% CI 1.08–6.25, P = 0.034) and a history of appendectomy (OR = 4.00, 95% CI 1.15–14.29, P = 0.029). Conclusions The factors contributing to early cancer detection were identified but their clinical value is limited. Diagnosis by symptoms suggesting CRC needs to be improved and CRC screening should be vigorously promoted.

There are currently no animal models for metastatic ocular melanoma. The lack of metastatic disease models has greatly hampered the research and development of novel strategies for the treatment of metastatic ocular melanoma. In this protocol we delineate a quick and efficient way to generate embryonic zebrafish models for both the primary and disseminated stage of ocular melanoma, using retro-orbital orthotopic and intravascular ectopic cell engraftment, respectively. Combining these two different engraftment strategies we can recapitulate the etiology of cancer in its totality, progressing from primary, localized tumor growth under the eye to a perivascular metastasis formation in the tail. These models allow us to quickly and easily modify the cancer cells prior to implantation with specific labeling, genetic or chemical interference; and to treat the engrafted hosts with (small molecular) inhibitors to attenuate tumor development.Here, we describe the generation and quantification of both orthotopic and ectopic engraftment of ocular melanomas (conjunctival and uveal melanoma) using fluorescently labelled stable cell lines. This protocol is also applicable for engraftment of primary cells derived from patient biopsy and patient/PDX derived material (manuscript in preparation). Within hours post engraftment cell migration and proliferation can be visualized and quantified. Both tumor foci are readily available for imaging with both epifluorescence microscopy and confocal microscopy. Using these models, we can confirm or refute the activity of either chemical or genetic inhibition strategies within as little as 8 days after the onset of the experiment, allowing not only highly efficient screening on stable cell lines, but also enables patient directed screening for precision medicine approaches.