Noriaki Koizumi

Detection of Lymph Node Metastases in Human Colorectal Cancer by Using 5-Aminolevulinic Acid-Induced Protoporphyrin IX Fluorescence with Spectral Unmixing

Accurate evaluation of metastatic lymph nodes (LNs) is indispensable for adequate treatment of colorectal cancer (CRC) patients. Here, we demonstrate detection of metastases of human CRC in removed fresh LNs using 5-aminolevulinic acid (ALA)-induced protoporphyrin IX (PpIX) fluorescence. A spectral unmixing method was employed to reduce the overlap of collagen autofluorescence on PpIX fluorescence. A total of 17 surgery patients with advanced CRC were included in this study. After 5-ALA at a dose of 15 mg/kg of body weight was applied orally 2 h prior to surgery, 87 LNs were subjected to spectral fluorescence imaging and histopathological diagnosis, and statistical analysis was performed. No apparent side effect was observed to be associated with 5-ALA administration. The spectral unmixing fluorescence intensity of PpIX in metastatic LNs was 10.2-fold greater than that in nonmetastaic LNs. The receiver-operating-characteristic (ROC) analysis showed that the area under the curve (AUC) was calculated as 0.95. Our results show the potential of 5-ALA-induced PpIX fluorescence processed by spectral unmixing for detecting metastases in excised fresh LNs from patients with CRC, suggesting that this rapid and feasible method is applicable to gross evaluation of resected LN samples in pathology laboratories.

Recent advances in photodynamic diagnosis of gastric cancer using 5-aminolevulinic acid

Photodynamic diagnosis based on 5-aminolevulinic acid-induced protoporphyrin IX has been clinically applied in many fields based upon its evidenced efficacy and adequate safety. In order to establish a personalized medicine approach for treating gastric cancer patients, rapid intraoperative detection of malignant lesions has become important. Feasibility of photodynamic diagnosis using 5-aminolevulinic acid for gastric cancer patients has been investigated, especially for the detection of peritoneal dissemination and lymph node metastasis. This method enables intraoperative real-time fluorescence detection of peritoneal dissemination, exhibiting higher sensitivity than white light observation without histopathological examination. The method also enables detection of metastatic foci within excised lymph nodes, exhibiting a diagnostic accuracy comparable to that of a current molecular diagnostics technique. Although several complicating issues still need to be resolved, such as the effect of tissue autofluorescence and the insufficient depth penetration of excitation light, this simple and rapid method has the potential to become a useful diagnostic tool for gastric cancer, as well as urinary bladder cancer and glioma.

Incidentally Discovered Adenocarcinoma in situ of the Appendix in a Young Woman

Primary appendiceal adenocarcinoma is an infrequent disease. This report presents a rare case of incidentally discovered carcinoma in situ of the appendix. A 35-year-old parturient female simultaneously underwent appendectomy and oophorectomy due to an ovarian abscess that adhered to the appendix during cesarean section. Although her excised appendix showed no apparent tumorous lesion, histopathological examination revealed carcinoma in situ in the excised appendix. She underwent additional right hemicolectomy a few days later due to the possibility of a positive surgical margin. Histopathological examination detected no malignant cells in the resected specimen. She was discharged without any complications and has since remained healthy. Appendiceal adenocarcinoma is generally considered to be difficult to diagnose during the early stage because it seldom shows any specific findings. This results in a poor prognosis. Histopathological examination is not always conducted for appendices resected during other surgery. However, the current study suggests that a careful routine histopathological examination of excised appendix, as well as careful preoperative examination and detailed intraperitoneal inspection during surgery, is indeed important to detect occult appendiceal tumors.

Raman microspectroscopy for visualization of peripheral nerves

The peripheral nervous system plays an important role in motility, sensory, and autonomic functions of the human body. Preservation of peripheral nerves in surgery is essential for improving quality of life of patients. To preserve peripheral nerves, detection of ne peripheral nerves that cannot be identi ed by human eye or under white light imaging is necessary. In this study, we sought to provide a proof-of-principle demonstration of a label-free detection technique of peripheral nerve tissues against adjacent tissues that employs spontaneous Raman microspectroscopy. A line-illumination confocal Raman microscope was used for the experiment. A laser operating at the wavelength of 532 nm was used as an excitation laser light. We obtained Raman spectra of peripheral nerve, brous connective tissue, skeletal muscle, blood vessel, and adipose tissue of Wistar rats, and extracted speci c spectral features of peripheral nerves and adjacent tissues. By applying multivariate image analysis, peripheral nerves were clearly detected against adjacent tissues without any preprocessing neither xation nor staining. These results suggest the potential of the Raman spectroscopic observation for noninvasive and label-free nerve detection, and we expect this method could be a key technique for nerve-sparing surgery.

Massive chronic irreducible rectal prolapse successfully treated with Altemeier’s procedure

Abstract The guideline for the treatment of rectal prolapse recommends that surgeons select appropriate surgical procedures individually based on each patient’s overall status. However, in cases of irreducible or incarcerated rectal prolapse, surgical options are quite limited. Here we present a case of an elderly woman with massive chronic irreducible rectal prolapse. An 87-year-old woman presented to our hospital with a complaint of massive rectal prolapse. The prolapsed rectum was over 20 cm long, and completely irreducible. She underwent perineal rectosigmoidectomy with levatorplasty known as Altemeier’s procedure. More than 30 cm of rectosigmoid colon was resected. After the operation, rectal prolapse was resolved completely. Her postoperative course was uneventful, and her quality of life and bowel movements improved. She has since been healthy without recurrence for over 2 years. Altemeier’s procedure is applicable even in cases of irreducible rectal prolapse and features acceptable safety and a satisfactory outcome.

Is Single-incision Laparoscopic Cholecystectomy Feasible for Acute Cholecystitis? A Consecutive Study of 60 Cases

The feasibility of single-incision laparoscopic cholecystectomy (SIL-C) for patients with acute cholecystitis were evaluated based on the timing of operation after onset of symptoms. Sixty patients with acute cholecystitis who underwent SIL-C were divided into 2 groups according to the timing of operation: group E included 23 patients who underwent SIL-C within 72 hours, and group O included 37 patients who underwent SIL-C later. There were no statistical differences between group E and group O in clinicopathologic characteristics. Group E demonstrated significantly shorter operating time and less blood loss than group O. Although the incidences of additional port(s) requirements were not significantly different, 8 patients in group O required open conversion, indicating significantly higher rate. As group E demonstrated favorable surgical outcomes compared with group O, SIL-C for acute cholecystitis seems to be a feasible therapeutic procedure when performed within 72 hours as updated Tokyo Guidelines recommended.

Single-Incision Laparoscopic Surgery for Undiagnosed Small Bowel Obstruction in a Patient without a History of Abdominal Surgery

We herein report a 66-year-old female patient who developed an undiagnosed small bowel obstruction without a history of prior abdominal surgery and was successfully treated by single-incision laparoscopic surgery. A small bowel obstruction with unknown cause typically requires some sort of surgical treatment in parallel with a definitive diagnosis. Although open abdominal surgery has been generally performed for the treatment of small bowel obstructions, laparoscopic surgery for small bowel obstructions has been increasing in popularity due to its less invasiveness, including fewer postoperative complications and a shorter hospital stay. As a much less invasive therapeutic strategy, we have performed single-incision laparoscopic surgery for the treatment of an undiagnosed small bowel obstruction. We were able to make a definitive diagnosis after sufficient intra-abdominal inspection and to perform enterotomy through a small umbilical incision. Single-incision laparoscopic surgery appears to be comparable to conventional laparoscopic surgery and provides improved cosmesis, although it is an optional strategy only applicable to selected patients.

In Vivo Detection of Rat Colorectal Cancers by using a Dual-Wavelength Excitation Method

Hypoxia is a characteristic feature of solid neoplasms, and insufficient oxygen supply increases cellular nicotinamide adenine dinucleotide (NADH) fluorescence, which is a main component of autofluorescence of the colorectal mucosa. We investigated whether a dual-wavelength excitation method which is optimized for sensing mucosal NADH fluorescence could be applicable to the detection of rat colorectal cancers in vivo. Rat colorectal adenocarcinomas were studied by using fluorescence stereomicroscopy. After autofluorescence images at 470 nm irradiated with dual-wavelength excitation at 365 nm (F365ex) and 405 nm (F405ex) were acquired, ratio images were produced by dividing F365ex by F405ex: The excitation-emission wavelength pairs in F365ex and F405ex were adjusted for acquisition of NADH fluorescence and reference fluorescence. Based on observations from the luminal surface in vivo, F365ex/F405ex ratio images indicated a 1.57-fold higher signal value in the cancers than in the surrounding normal mucosa. The signal values in F365ex/F405ex ratio images were less mutually related with the hemoglobin concentration index. Small adenocarcinomas (less than 4 mm) could be detected on F365ex/F405ex ratio images. The results showed that NADH fluorescence measurement with little interference from tissue hemoglobin is efficient for visualizing rat colorectal cancers in vivo, suggesting that the dual-wavelength excitation method has potential for label-free endoscopic detection of diminutive colorectal neoplasms.