Fluorescence-Based Microendoscopic Sensing System for Minimally Invasive In Vivo Bladder Cancer Diagnosis

Abstract

Bladder cancer is commonly diagnosed by evaluating the tissue morphology through cystoscopy, and tumor resection is used as the primary treatment approach. However, these methods are limited by lesion site specificity and resection margin, and can thereby fail to detect cancer lesions at early stages. Nevertheless, rapid diagnosis without biopsy may be possible through fluorescence sensing. Herein, we describe a minimally invasive imaging system capable of sensing even small tumors through a 1.2 mm diameter flexible fiber bundle microprobe. We demonstrate that this new device can be used for the early diagnosis of bladder cancer in rats. Bladder cancer was induced in rats using the carcinogen N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN), and a togglable filter capable of PpIX fluorescence sensing was installed in the microendoscopic system. Following 5-aminolevulinic acid administration, tissue in the early stages of bladder cancer was successfully identified with fluorescence detection and confirmed with hematoxylin/eosin and ferrochelatase staining. Although the time required for BBN to induce bladder cancer varied between 3 and 4 weeks among the rats, the microendoscopic system allowed the minimally invasive follow-up on cancer development.

Nanotechnology and Cancer Bioelectricity: Bridging the Gap Between Biology and Translational Medicine

“…For example, breast cancer cells exhibit higher faradaic currents when compared to their healthy counterparts. [32] Similar phenomena have been observed in other types of cancer, including lung, [63] pancreatic, [86] and bladder [87] cancer. By interfacing cancer cells with electrodes, it is possible to artificially control redox reactions.…”

“…[164] For example, nanotechnologies were employed to aid the diagnosis of oral cancer, [135] breast cancer, [165] prostate cancer, [165] and ovarian cancer. [166] There is a vast literature on cancer diagnostics based on fluorescence, [87,167,168] colorimetry, [133] chemoluminescence, [169] surface enhanced Raman scattering (SERS), [170] surface charge sensing, [91] and electrochemical sensing, [165,171] to detect nucleicacids, [172] aptamers, [173,174] and other cancer biomarkers. [175] These involve the employment of different materials and devices, including nanoparticles, [135,174,176,177] field-effect transistors, [164] and 2D materials.…”

“…The nanoparticle-cell complex is designed such to exhibit optical properties which allow its selective visualization using imaging techniques, including magnetic resonance imaging (MRI) or computed tomography (CT) scanning. [87,164,183] (iii) Sensing. Charged nanoparticles can also be used to detect cancer biomarkers.…”