IRIS U kit usefulness in transanal total mesorectal excision for lower rectal cancer to avoid urethral injury.

Transanal total mesorectal excision (taTME) has improved the laparoscopic dissection for rectal cancer in the narrow pelvis. Although taTME has more clinical benefits than laparoscopic surgery, such as a better view of the distal rectum and direct determination of distal resection margin, an intraoperative urethral injury could occur in excision ta-TME. This study aimed to determine the feasibility and efficacy of the ta-TME with IRIS U kit surgery. This retrospective study enrolled 10 rectal cancer patients who underwent a taTME with an IRIS U kit. The study endpoints were the safety of access (intra- or postoperative morbidity). The detectability of the IRIS U kit catheter was investigated by using a laparoscope-ICG fluorescence camera system. Their mean age was 71.4±6.4 (58-78) years; 80 were men, and 2 were women. The mean operative time was 534.6 ± 94.5 min. The coloanal anastomosis was performed in 80%, and 20% underwent abdominal peritoneal resection. Two patients encountered postoperative complications graded as Clavien-Dindo grade 2. The transanal approach with IRIS U kit assistance is feasible, safe for patients with lower rectal cancer, and may prevent intraoperative urethral injury.

Scintillation of polyester fabric and clothing via proton irradiation and its utilization in surface imaging of proton pencil beams.

In the realm of radiation therapy, a conspicuous obstacle lies in the dearth of external observation concerning radiation beams aimed at the patient. While real-time monitoring of such beams on the patient's surface during therapy holds promise, the imaging of particle beams has thus far proven to be a formidable task. Here, we show our discovery of polyester fabrics and cloths as auspicious scintillating materials, ideally suited for the visualization of radiation beams upon the patient's surface. The light output of polyester fabrics ranged from 10 to 20% of that observed in plastic scintillators. When exposed to spot scanning proton beams, clear beam spots emerged on the surface of the polyester cloths. The movement of these scanning beams was effectively captured using a CMOS camera in a light-shield-free with lights-off environment. The resulting images provided a means for evaluating spills of the proton beams. The inherent flexibility of polyester fabrics and clothing enhances their appeal for applications in the intricate landscape of radiation therapy, promising a bright future for surface beam imaging endeavors.

A triple-imaging-modality system for simultaneous measurements of prompt gamma photons, prompt x-rays, and induced positrons during proton beam irradiation.

Objective. Prompt gamma photon, prompt x-ray, and induced positron imaging are possible methods for observing a proton beam's shape from outside the subject. However, since these three types of images have not been measured simultaneously nor compared using the same subject, their advantages and disadvantages remain unknown for imaging beam shapes in therapy. To clarify these points, we developed a triple-imaging-modality system to simultaneously measure prompt gamma photons, prompt x-rays, and induced positrons during proton beam irradiation to a phantom.Approach. The developed triple-imaging-modality system consists of a gamma camera, an x-ray camera, and a dual-head positron emission tomography (PET) system. During 80 MeV proton beam irradiation to a polymethyl methacrylate (PMMA) phantom, imaging of prompt gamma photons was conducted by the developed gamma camera from one side of the phantom. Imaging of prompt x-rays was conducted by the developed x-ray camera from the other side. Induced positrons were measured by the developed dual-head PET system set on the upper and lower sides of the phantom.Main results. With the proposed triple-imaging-modality system, we could simultaneously image the prompt gamma photons and prompt x-rays during proton beam irradiation. Induced positron distributions could be measured after the irradiation by the PET system and the gamma camera. Among these imaging modalities, image quality was the best for the induced positrons measured by PET. The estimated ranges were actually similar to those imaged with prompt gamma photons, prompt x-rays and induced positrons measured by PET.Significance. The developed triple-imaging-modality system made possible to simultaneously measure the three different beam images. The system will contribute to increasing the data available for imaging in therapy and will contribute to better estimating the shapes or ranges of proton beam.

Estimating blurless and noise-free Ir-192 source images from gamma camera images for high-dose-rate brachytherapy using a deep-learning approach.

Objective. Precise monitoring of the position and dwell time of iridium-192 (Ir-192) during high-dose-rate (HDR) brachytherapy is crucial to avoid serious damage to normal tissues. Source imaging using a compact gamma camera is a potential approach for monitoring. However, images from the gamma camera are affected by blurring and statistical noise, which impact the accuracy of source position monitoring. This study aimed to develop a deep-learning approach for estimating ideal source images that reduce the effect of blurring and statistical noise from experimental images captured using a compact gamma camera.Approach. A double pix2pix model was trained using the simulated gamma camera images of an Ir-192 source. The first model was responsible for denoising the Ir-192 images, whereas the second model performed super resolution. Trained models were then applied to the experimental images to estimate the ideal images.Main results. At a distance of 100 mm between the compact gamma camera and the Ir-192 source, the difference in full width at half maximum (FWHM) between the estimated and actual source sizes was approximately 0.5 mm for a measurement time of 1.5 s. This difference has been improved from approximately 2.7 mm without the use of DL. Even with a measurement time of 0.1 s, the ideal images could be estimated as accurately as in the 1.5 s measurements. This method consistently achieved accurate estimations of the source images at any position within the field of view; however, the difference increased with the distance between the Ir-192 source and the compact gamma camera.Significance. The proposed method successfully provided estimated images from the experimental images within errors smaller than 0.5 mm at 100 mm. This method is promising for reducing blurring and statistical noise from the experimental images, enabling precise real-time monitoring of Ir-192 sources during HDR brachytherapy.

Bilateral laparosocopic lateral lymph node dissection by the totally extraperitoneal approach after intersphincteric resection of the lower rectum: report of a case.

Introduction and Importance: Lateral lymph node dissection (LLND) for recurrent lateral pelvic lymph node metastasis could be the only surgical treatment to improve its prognosis, but is difficult and challenging technically. Case Presentation: A 75-year-old Japanese man who underwent a radical laparoscopic intersphincteric resection to treat double lower rectal cancer. Computed tomography and MRI showed lower rectal wall thickening and bilateral lateral lymph node swelling. The authors scheduled and performed the LLND for recurrent lateral pelvic lymph nodes after ISR by the totally extraperitoneal (TEP) approach. The bottom of the obturators lymph node (#263D) were positive for metastasis histologically. Clinical Discussion: The TEP approach is an especially effective option for the treatment of bilateral LLND. Conclusion: Herein, the authors introduce our surgical technique: successful challenging treatment of the LLND by the TEP approach after intersphincteric resection of the lower rectum.

Luminescence imaging of water irradiated by protons under FLASH radiation therapy conditions.

Objective.FLASH radiation therapy with ultrahigh dose rates (UHDR) has the potential to reduce damage to normal tissue while maintaining anti-tumor efficacy. However, rapid and precise dose distribution measurements remain difficult for FLASH radiation therapy with proton beams. To solve this problem, we performed luminescence imaging of water following irradiation by a UHDR proton beam captured using a charge-coupled device camera.Approach. We used 60 MeV proton beams with dose rates of 0.03-837 Gy s-1from a cyclotron. Therapeutic 139.3 MeV proton beams with dose rates of 0.45-4320 Gy s-1delivered by a synchrotron-based proton therapy system were also tested. The luminescent light intensity induced by the UHDR beams was compared with that produced by conventional beams to compare the dose rate dependency of the light intensity and its profile.Main results. Luminescence images of water were clearly visualized under UHDR conditions, with significantly shorter exposure times than those with conventional beams. The light intensity was linearly proportional to the delivered dose, which is similar to that of conventional beams. No significant dose-rate dependency was observed for 0.03-837 Gy s-1. The light-intensity profiles of the UHDR beams agreed with those of conventional beams. The results did not differ between accelerators (synchrotron or cyclotron) and beam energies.Significance. Luminescence imaging of water is achievable with UHDR proton beams as well as with conventional beams. The proposed method should be suitable for rapid and easy quality assurance investigations for proton FLASH therapy, because it facilitates real-time, filmless measurements of dose distributions, and is useful for rapid feedback.

Simultaneous imaging of luminescence and prompt x-rays during irradiation with spot-scanning proton beams at clinical dose level.

Prompt x-ray imaging is a promising method for observing the beam shape from outside a subject. However, its distribution is different from dose distribution, and thus a comparison with the dose is required. Meanwhile, luminescence imaging of water is a possible method for imaging the dose distribution. Consequently, we performed simultaneous imaging of luminescence and prompt x-rays during irradiation by proton beams to compare the distributions between these two different imaging methods. Optical imaging of water was conducted with spot-scanning proton beams at clinical dose level during irradiation to a fluorescein (FS) water phantom set in a black box. Prompt x-ray imaging was also conducted simultaneously from outside the black box using a developed x-ray camera during proton beam irradiation to the phantom. We measured images of the luminescence of FS water and prompt x-rays for various types of proton beams, including pencil beams, spread-out Bragg peak (SOBP) beams, and clinically used therapy beams. After the imaging, ranges were estimated from FS water and prompt x-rays and compared with those calculated with a treatment planning system (TPS). We could measure the prompt x-ray and FS water images simultaneously for all types of proton beams. The ranges estimated from the FS water and those calculated with the TPS closely matched, within a difference of several mm. Similar range difference was found between the results estimated from prompt x-ray images and those calculated with the TPS. We confirmed that the simultaneous imaging of luminescence and prompt x-rays were possible during irradiation with spot-scanning proton beams at a clinical dose level. This method can be applied to range estimation as well as comparison with the dose for prompt x-ray imaging or other imaging methods used in therapy with various types of proton beams at a clinical dose level.

Hybrid imaging of prompt x-rays and induced positrons using a pinhole gamma camera during and after irradiation of protons.

Objective. Prompt x-ray imaging using a low-energy x-ray camera is a promising method for observing a proton beam's shape from outside the subject. Furthermore, imaging of positrons produced by nuclear reactions with protons is a possible method for observing the beam shape. However, it has not been possible to measure these two types of images with a single imaging system due to the limited imaging capability of existing systems. Imaging of both prompt x-rays and the distribution of positrons may compensate for the shortcomings of each method.Approach. We conducted imaging of the prompt x-ray using a pinhole x-ray camera during irradiation with protons in list mode. Then, after irradiation with protons, imaging of annihilation radiations from the produced positrons was conducted using the same pinhole x-ray camera in list mode. After this imaging, list-mode data were sorted to obtain prompt x-ray images and positron images.Main results. With the proposed procedure, we could measure both prompt x-ray images and induced positron images with a single irradiation by a proton beam. From the prompt x-ray images, ranges and widths of the proton beams could be estimated. The distributions of positrons were slightly wider than those of the prompt x-rays. From the time sequential positron images, we could derive the time activity curves of the produced positrons.Significance. Hybrid imaging of prompt x-rays and induced positrons using a pinhole x-ray camera was achieved. The proposed procedure would be useful for measuring prompt x-ray images during irradiation to estimate the beam structures as well as for measuring the induced positron images after irradiation to estimate the distributions and time activity curves of the induced positrons.

Successful treatment for sports hernia by total extraperitoneal repair with intraperitoneal examination: Report a case.

Introduction: and importance: TEP might be one of options for treating such a sports hernia. Case presentation: An 18-year-old Japanese male presented with right groin pain for approximately two years. The pain was initially felt on the right side only, especially on kicking. We assessed the patient using laparoscopic examination with an intra-abdominal scope and subsequently diagnosed a sports hernia with a bilateral internal inguinal hernia. We then performed total extraperitoneal repair (TEP) for its treatment. The patient had a good postoperative course and was discharged from our hospital in remission after 3 days. Finally, the patient was able to play soccer without groin pain. Clinical discussion: Chronic groin pain in athletes can be caused by a bulge in the posterior inguinal wall, consistent with an incipient direct inguinal hernia. Conclusion: We show that intraperitoneal examination with TEP might be one of options for treating such a sports hernia. Endoscopic placement of the retropubic mesh must be considered an important option for this type of hernia.

Optimization of the energy window setting in Ir-192 source imaging for high-dose-rate brachytherapy using a YAP(Ce) gamma camera.

PURPOSE: Although real-time imaging of the high-activity iridium-192 (Ir-192) source position during high-dose-rate (HDR) brachytherapy using a high-energy gamma camera system is a promising approach, the energy window was not optimized for spatial resolution or scatter fraction. METHODS: By using a list-mode data-acquisition system that can acquire energy information of a cerium-doped yttrium aluminum perovskite (YA1O3: YAP(Ce)) gamma camera, we tried to optimize the energy window's setting to improve the spatial resolution and reduce scatter fraction. RESULTS: The spatial resolution was highest for the central energy of the window at ∼300 keV. The scatter fraction was also smallest for the central energy of the window at ∼300 keV, and the scatter fraction was more than 48 % smaller than that for the full energy window. CONCLUSIONS: We clarified that the spatial resolution can be improved and the scatter fraction can be reduced through optimizing the energy window of the YAP(Ce) gamma camera by setting the central energy of the window to ∼300 keV for HDR brachytherapy.

Technical note: Short-time sequential high-energy gamma photon imaging using list-mode data acquisition system for high-dose-rate brachytherapy.

PURPOSE: Measurement of the dwell time and moving speed of a high-activity iridium-192 (Ir-192) source used for high-dose-rate (HDR) brachytherapy is important for estimating the precise dose delivery to a tumor. For this purpose, we used a cerium-doped yttrium aluminum perovskite (YA1O3 :YAP(Ce)) gamma camera system, combined with a list-mode data acquisition system that can acquire short-time sequential images, and measured the dwell times and moving speeds of the Ir-192 source. METHODS: Gamma photon imaging was conducted using the gamma camera in list mode for the Ir-192 source of HDR brachytherapy with fixed dwell times and positions. The acquired list-mode images were sorted to millisecond-order interval time sequential images to evaluate the dwell time at each position. Time count rate curves were derived to calculate the dwell time at each source position and moving speed of the source. RESULTS: We could measure the millisecond-order time sequential images for the Ir-192 source. The measured times for the preset dwell times of 2 s and 10 s were 1.98 to 2.00 s full width at half maximum (FWHM) and 10.0 s FWHM, respectively. The dwell times at the first dwell position were larger than those at other positions. We also measured the moving speeds of the source after the dwells while moving back to the afterloader and found the speed increased with the distance from the edge of the field of view to the last dwell position. CONCLUSION: We conclude that millisecond-order time sequential imaging of the Ir-192 source is possible by using a gamma camera and is useful for evaluating the dwell times and moving speeds of the Ir-192 source.

ARDS Clinical Practice Guideline 2021.

BACKGROUND: The joint committee of the Japanese Society of Intensive Care Medicine/Japanese Respiratory Society/Japanese Society of Respiratory Care Medicine on ARDS Clinical Practice Guideline has created and released the ARDS Clinical Practice Guideline 2021. METHODS: The 2016 edition of the Clinical Practice Guideline covered clinical questions (CQs) that targeted only adults, but the present guideline includes 15 CQs for children in addition to 46 CQs for adults. As with the previous edition, we used a systematic review method with the Grading of Recommendations Assessment Development and Evaluation (GRADE) system as well as a degree of recommendation determination method. We also conducted systematic reviews that used meta-analyses of diagnostic accuracy and network meta-analyses as a new method. RESULTS: Recommendations for adult patients with ARDS are described: we suggest against using serum C-reactive protein and procalcitonin levels to identify bacterial pneumonia as the underlying disease (GRADE 2D); we recommend limiting tidal volume to 4-8 mL/kg for mechanical ventilation (GRADE 1D); we recommend against managements targeting an excessively low SpO2 (PaO2) (GRADE 2D); we suggest against using transpulmonary pressure as a routine basis in positive end-expiratory pressure settings (GRADE 2B); we suggest implementing extracorporeal membrane oxygenation for those with severe ARDS (GRADE 2B); we suggest against using high-dose steroids (GRADE 2C); and we recommend using low-dose steroids (GRADE 1B). The recommendations for pediatric patients with ARDS are as follows: we suggest against using non-invasive respiratory support (non-invasive positive pressure ventilation/high-flow nasal cannula oxygen therapy) (GRADE 2D), we suggest placing pediatric patients with moderate ARDS in the prone position (GRADE 2D), we suggest against routinely implementing NO inhalation therapy (GRADE 2C), and we suggest against implementing daily sedation interruption for pediatric patients with respiratory failure (GRADE 2D). CONCLUSIONS: This article is a translated summary of the full version of the ARDS Clinical Practice Guideline 2021 published in Japanese (URL: https://www.jsicm.org/publication/guideline.html ). The original text, which was written for Japanese healthcare professionals, may include different perspectives from healthcare professionals of other countries.

Technical note: Correcting angular dependencies using non-polarized components of Cherenkov light in water during high-energy X-ray irradiation.

OBJECTIVE: Dose distribution measurements of high-energy X-rays from medical linear accelerators (LINAC) in water are important for quality control (QC) of the system. Although Cherenkov-light imaging is a useful method for measuring the high-energy X-ray dose distribution, depth profiles have an underestimated dose at increased depths due to the angular dependency of the Cherenkov light generated in water. In this study, we use a linear polarizer to separate the majority of polarized components from the majority of unpolarized components of Cherenkov-light images in water and then use this information to correct for angular dependencies. METHODS: A water phantom, a cooled charge-coupled device (CCD) camera, and a polarizer were installed in a black box. Then, the water phantom was irradiated from the upper side with 6 or 10 MV X-rays, and the Cherenkov light generated in water was imaged with the polarizer axis at both parallel and perpendicular orientations to the beam. By using these images from the two orientations relative to the beam, we corrected the angular dependency of the Cherenkov light. RESULTS: By subtracting the images measured with the polarizer perpendicular to the beams from the images measured with the polarizer parallel to the beams, we could obtain images with only the polarized components. Using these images, we could calculate the images with non-polarized components that had similar depth profiles to those calculated with a planning system. The average difference between corrected depth profiles and those calculated with the planning system was less than 1%, while that between uncorrected depth profiles and the planning system was more than 8.3% in depths of water from 20 to 100 mm. CONCLUSION: We conclude that the use of the polarizer has the potential to improve the accuracy of dose distribution in Cherenkov-light imaging of water using high-energy X-rays.

ARDS clinical practice guideline 2021.

BACKGROUND: The joint committee of the Japanese Society of Intensive Care Medicine/Japanese Respiratory Society/Japanese Society of Respiratory Care Medicine on ARDS Clinical Practice Guideline has created and released the ARDS Clinical Practice Guideline 2021. METHODS: The 2016 edition of the Clinical Practice Guideline covered clinical questions (CQs) that targeted only adults, but the present guideline includes 15 CQs for children in addition to 46 CQs for adults. As with the previous edition, we used a systematic review method with the Grading of Recommendations Assessment Development and Evaluation (GRADE) system as well as a degree of recommendation determination method. We also conducted systematic reviews that used meta-analyses of diagnostic accuracy and network meta-analyses as a new method. RESULTS: Recommendations for adult patients with ARDS are described: we suggest against using serum C-reactive protein and procalcitonin levels to identify bacterial pneumonia as the underlying disease (GRADE 2D); we recommend limiting tidal volume to 4-8 mL/kg for mechanical ventilation (GRADE 1D); we recommend against managements targeting an excessively low SpO2 (PaO2) (GRADE 2D); we suggest against using transpulmonary pressure as a routine basis in positive end-expiratory pressure settings (GRADE 2B); we suggest implementing extracorporeal membrane oxygenation for those with severe ARDS (GRADE 2B); we suggest against using high-dose steroids (GRADE 2C); and we recommend using low-dose steroids (GRADE 1B). The recommendations for pediatric patients with ARDS are as follows: we suggest against using non-invasive respiratory support (non-invasive positive pressure ventilation/high-flow nasal cannula oxygen therapy) (GRADE 2D); we suggest placing pediatric patients with moderate ARDS in the prone position (GRADE 2D); we suggest against routinely implementing NO inhalation therapy (GRADE 2C); and we suggest against implementing daily sedation interruption for pediatric patients with respiratory failure (GRADE 2D). CONCLUSIONS: This article is a translated summary of the full version of the ARDS Clinical Practice Guideline 2021 published in Japanese (URL: https://www.jrs.or.jp/publication/jrs_guidelines/). The original text, which was written for Japanese healthcare professionals, may include different perspectives from healthcare professionals of other countries.

Laparoscopic intraperitoneal mesh repair of an incisional hernia after transverse rectus abdominis myocutaneous flap reconstruction for breast cancer.

Breast reconstruction with transverse rectus abdominis myocutaneous (TRAM) flap is performed for the treatment of large defects of the breast. However, this may result in an abdominal wall hernia or bulging. A 53-year-old Japanese woman with left breast cancer underwent left skin-sparing mastectomy, sentinel node lymph node dissection, and immediate reconstruction with a contralateral pedicled TRAM flap. Thirty-two months following surgery, right lower abdominal wall hernia (15.5 × 12 cm) and bulging were observed at the suprapubic region. The patient was diagnosed with an incisional hernia and was scheduled for laparoscopic intraperitoneal mesh repair. The mesh was coated with an absorbable hydrogel barrier and was trimmed to 26 × 22 cm, with a 5 cm overlap around the defect. The patient demonstrated a good postoperative course. In conclusion, intraperitoneal onlay mesh with hernia repair closure (IPOM-Plus) is a simple and useful method for hernia repair following TRAM flap reconstruction.

Multi-modal 3D imaging of radionuclides using multiple hybrid Compton cameras.

For radiological diagnosis and radionuclide therapy, X-ray and gamma-ray imaging technologies are essential. Single-photon emission tomography (SPECT) and positron emission tomography (PET) play essential roles in radiological diagnosis, such as the early detection of tumors. Radionuclide therapy is also rapidly developing with the use of these modalities. Nevertheless, a limited number of radioactive tracers are imaged owing to the limitations of the imaging devices. In a previous study, we developed a hybrid Compton camera that conducts simultaneous Compton and pinhole imaging within a single system. In this study, we developed a system that simultaneously realizes three modalities: Compton, pinhole, and PET imaging in 3D space using multiple hybrid Compton cameras. We achieved the simultaneous imaging of Cs-137 (Compton mode targeting 662 keV), Na-22 (PET mode targeting 511 keV), and Am-241 (pinhole mode targeting 60 keV) within the same field of view. In addition, the imaging of Ga-67 and In-111, which are used in various diagnostic scenarios, was conducted. We also verified that the 3D distribution of the At-211 tracer inside a mouse could be imaged using the pinhole mode.

A case report of the transanal lateral lymph node dissection with a combined abdominal assisted approach for the lower rectal cancer.

INTRODUCTION: Low and mid rectal cancer cells have the tendency to spread in the lateral pelvic lymph node (LPLN). The Japanese guidelines recommend systematic lymph node dissection when a positive LPLN is suspected or in stages II-III rectal cancer. However, laparoscopic lymph node dissection is complex and challenging. We introduce transanal LPLN dissection using an abdominal approach. PRESENTATION OF CASE: A 78-year-old man was diagnosed with advanced rectal cancer. Computed tomography and magnetic resonance imaging showed lower rectal wall thickening and bilateral lateral lymph node swelling. We performed laparoscopic abdominal peritoneal resection with combined bilateral LPLN dissection using abdominal and transanal approaches. He had an uneventful postoperative course with no signs of recurrence at the 5-month follow-up. DISCUSSION: LPLN metastases for low rectal cancer especially occur at the bottom of the deep pelvic spaces. As laparoscopic LPLND for low rectal cancer can be complicated, we adopted abdominal and transanal approaches, which provide the advantage of an anatomical view. This procedure may improve lateral pelvic anatomical structure viewing, and may offer advantages over laparoscopic abdominal approaches for visualizing and dissecting LPLNs. CONCLUSION: Curative resection has become available for rectal cancer with transanal LPLN dissection. LPLN dissection with combined abdominal and transanal approaches is a feasible treatment for advanced rectal cancer.

A study of the effectiveness of the bilateral and contralateral occult inguinal hernia repair by total extraperitoneal repair with intraperitoneal examination.

PURPOSE: Of the various methods used, the laparoscopic surgical repair of inguinal hernias is widely performed. We aimed to estimate the incidence of bilateral and contralateral occult inguinal hernias in our surgical population and to compare the results of total extraperitoneal repair (TEP) for bilateral and unilateral inguinal hernias, occult and non-occult hernias. METHODS: We retrospectively reviewed data of patients who underwent TEP for the repair of adult inguinal hernias from January 2012 to November 2018 in our hospital. RESULTS: Of the data of 259 patients included, 134 (51.7%) and 125 (48.3%) had unilateral and bilateral inguinal hernias, respectively, while 70 patients (27%) were found to have a contralateral occult inguinal hernia, intraoperatively. The mean operative time was 129 ± 48 minutes (range, 43-300 minutes) and 167 ± 55 minutes (range, 85-390 minutes) for the unilateral and bilateral groups, respectively, indicating a significantly longer duration of surgery for the bilateral group (P < .05). Recurrence occurred in 1.5% (5/134) and 0.4% (1/250) of the operated hernias in the unilateral and the bilateral groups, respectively, indicating a significantly lower rate of recurrence in the latter group (P < .05). The two groups showed no statistically significant differences with respect to the remaining perioperative data. The incidence of postoperative complications in occult hernias was not significantly different from that in non-occult hernias. CONCLUSIONS: Our TEP method, involving a laparoscopic exploration from the intraperitoneal side, can be safely and effectively utilized for the repair of both bilateral and contralateral occult inguinal hernias.

Clinical outcome of the Gant-Miwa-Thiersch procedure for colonic mucosal prolapse after intersphincteric resection-a single-center report from Japan.

INTRODUCTION: Dysfunctions such as mucosal prolapse occur after intersphincteric resection (ISR) to treat lower rectal cancer, even when it is possible to preserve the anus. METHOD: We analyzed the data of 12 patients with rectal or colonic prolapse who underwent the Gant-Miwa-Thiersch procedure between March 2017 and May 2021. RESULT: There were no severe postoperative complications or recurrences. CASE PRESENTATION: A 75-year-old Japanese man initially underwent ISR and had mucosal prolapse nine months after his initial operation. We performed the Gant-Miwa-Thiersch procedure for colonic mucosal prolapse after ISR. SURGICAL PROCEDURE: Our procedure is a perineal plication method of prolapsed colonic mucosa with nylon wiring (The Gant-Miwa procedure), using a 1-nylon wire encircled three times to straighten the anal canal, with a cord inserted above the internal sphincter muscle (Thiersch procedure). DISCUSSION: Mucosal plication is performed via the Gant-Mowa or Delorme procedure to reduce the risk of recurrence. However, mucosal plication can be performed many times. Our Thiersch procedure involves encircling and straightening the anal canal with a 1-nylon wire to fix the new internal anal sphincter. In conclusion, the Gant-Miwa-Thiersch procedure for rectal and colonic mucosal prolapse, especially after ISR, is a viable treatment option.

Collision Tumor Comprising Primary Malignant Lymphoma and Adenocarcinoma in the Ascending Colon.

We describe the case of a 78-year-old man with collision tumor from the primary malignant lymphoma and adenocarcinoma in the ascending colon. He suffered anemia from sigmoid colon cancer, and colonoscopy revealed early-stage colorectal cancer with a diameter of 20 mm in the cecum, the biopsy specimen showed moderately differentiated adenocarcinoma. Contrast-enhanced computed tomography (CT) revealed bowel wall thickening with contrast enhancement at the cecum; however, no lymph node and organ metastases were found. As above, we performed laparoscopic ileocecal resection with D3 lymph node dissection. The postoperative course was uneventful, and he was discharged from the hospital on postoperative day 11. Histopathological findings were moderately differentiated adenocarcinoma which invaded the muscularis propria and serosa from the submucosa, while the adjacent serosa showed a highly diffuse proliferation of atypical cells with an irregular nuclear-to-cytoplasmic ratio. Besides, immunohistochemical staining findings were diffuse large B-cell lymphoma, and diffuse large B-cell lymphoma was coexistent with moderately differentiated adenocarcinoma. We treated the patient with cyclophosphamide, doxorubicin, vincristine, and prednisolone in combination with rituximab (R-CHOP therapy) during 3 months postoperatively. When the 8 courses had been completed, postoperative positron emission tomography-CT (PET-CT) confirmed complete response, and the disease control has been doing well. Malignant lymphoma of the colorectal region is relative rare, and the occurrence of synchronous lymphoma and adenocarcinoma of the colon is also rare. Furthermore, collision tumor by these different entities is very unusual. We presented here such a case. The accurate clinical determination of the dominant tumor and a close follow-up is required for proper treatment in these cases.