Clinicopathological features and prognosis of primary small bowel adenocarcinoma: a large multicenter analysis of the JSCCR database in Japan

BACKGROUND

The clinicopathological features and prognosis of primary small bowel adenocarcinoma (PSBA), excluding duodenal cancer, remain undetermined due to its rarity in Japan.

METHODS

We analyzed 354 patients with 358 PSBAs, between January 2008 and December 2017, at 44 institutions affiliated with the Japanese Society for Cancer of the Colon and Rectum.

RESULTS

The median age was 67 years (218 males, 61.6%). The average tumor size was 49.9 (7-100) mm. PSBA sites consisted of jejunum (66.2%) and ileum (30.4%). A total of 219 patients (61.9%) underwent diagnostic small bowel endoscopy, including single-balloon endoscopy, double-balloon endoscopy, and capsule endoscopy before treatment. Nineteen patients (5.4%) had Lynch syndrome, and 272 patients (76.8%) had symptoms at the initial diagnosis. The rates for stages 0, I, II, III, and IV were 5.4%, 2.5%, 27.1%, 26.0%, and 35.6%, respectively. The 5-year overall survival rates at each stage were 92.3%, 60.0%, 75.9%, 61.4%, and 25.5%, respectively, and the 5-year disease-specific survival (DSS) rates were 100%, 75.0%, 84.1%, 59.3%, and 25.6%, respectively. Patients with the PSBA located in the jejunum, with symptoms at the initial diagnosis or advanced clinical stage had a worse prognosis. However, multivariate analysis using Cox-hazard model revealed that clinical stage was the only significant predictor of DSS for patients with PSBA.

CONCLUSIONS

Of the patients with PSBA, 76.8% had symptoms at the initial diagnosis, which were often detected at an advanced stage. Detection during the early stages of PSBA is important to ensure a good prognosis.

Takotsubo cardiomyopathy in Guillain-Barré syndrome

BACKGROUND AND PURPOSE

Takotsubo cardiomyopathy (TCM) is a serious autonomic complication of Guillain-Barré syndrome (GBS). However, the association between TCM and GBS has not been investigated in detail. We investigated the characteristics of GBS patients with TCM (GBS-TCM).

METHODS

Clinical features and anti-ganglioside antibody between the GBS-TCM patients and 62 classical GBS patients without TCM as control patients were compared.

RESULTS

Eight GBS-TCM patients were identified, in whom TCM was diagnosed at a mean of 6.5 [range 3-42] days after the onset of GBS. The age at onset of GBS was elder in the GBS-TCM patients than in the control GBS patients (76.5 [56-87] vs. 52 [20-88] years, p < 0.01). Notably, cranial nerve deficits, particularly in the lower cranial nerves, were observed in all GBS-TCM patients (100% vs. 41.9%, p < 0.01). Additionally, the GBS-TCM patients showed a higher GBS disability score at nadir (5 [4-5] vs. 4 [1-5], p < 0.01), and lower Medical Research Council sum scores at admission and nadir (37 [30-44] vs. 48 [12-60] at admission, p < 0.05, and 20 [12-44] vs. 40 [0-60] at nadir, p < 0.05, respectively). Mechanical ventilation was more frequently required in the GBS-TCM patients (62.5% vs. 11.3%, p < 0.01). Three GBS-TCM patients were positive for anti-ganglioside antibodies.

CONCLUSIONS

TCM occurred at a relatively early phase of GBS. The characteristics of GBS-TCM were the elder, lower cranial nerve involvements, severe limb weakness, and respiratory failure.

Endoscopic treatment of anastomotic leakage after colorectal surgery by using polyglycolic acid sheets and fibrin glue

We describe the case of a 66-year-old man with an anastomotic fistula after rectal surgery, which was treated colonoscopically using polyglycolic acid sheets and fibrin glue. Polyglycolic acid sheets and fibrin glue have been used in thoracic surgery and otolaryngology to reinforce sutures and prevent air leakage. There have been recent reports of their use in endoscopic surgery for the closure of intraoperative perforations after endoscopic submucosal dissection and for fistula closure after upper gastrointestinal tract surgery. However, anastomotic fistulas in colorectal surgery are difficult to visualize endoscopically and may be difficult to suture with clips due to fibrosis. Polyglycolic acid sheets can be easily trimmed, and the fistula can be easily filled using these sheets; moreover, using fibrin glue to fix the sheets may enable fistula closure in areas that are difficult to visualize endoscopically.

Long-term survival and functional outcomes of laparoscopic surgery for clinical stage I ultra-low rectal cancers located within 5 cm of the anal verge: A prospective phase II trial (Ultimate trial)

OBJECTIVE

To clarify the long-term oncological outcomes and postoperative anal, urinary, and sexual functions after laparoscopic surgery for clinical stage I very low rectal carcinoma located near the anal canal.

SUMMARY BACKGROUND DATA

Laparoscopic surgery is widely applied for rectal cancer; however, concerns remain, with some studies showing poorer outcomes compared to open surgery.

METHODS

This single-arm, phase II trial included patients registered preoperatively from 47 institutions in Japan. The planned sample size was 300. The primary endpoint was the 3-year local recurrence rate. Anal, urinary, and sexual functions were evaluated using a prospective questionnaire.

RESULTS

Three-hundred patients were registered between January 2014 and March 2017. Anus-preserving surgery was performed in 278 (93%), including 172 who underwent intersphincteric resection (58%) and 106 (36%) who underwent low anterior resection. The 3-year cumulative local recurrence rate was 6.3%. At 3 years postoperatively, 87% of patients used their own anus, and the median incontinence score improved from 12 at 3 months to 8 at 3 years. Only 5% of patients had severe incontinence (incontinence score of 16 points). Postoperative urinary function evaluation showed that International Prostate Symptom Score and Overactive Bladder Symptom Score decreased 1 week after surgery, but recovered to preoperative level 1 month after surgery. International Consultation on Incontinence Questionnaire-Sort Form remained almost stable after surgery. Sexual function evaluation using the International Index of Erectile Function-5 and International Index of Erectile Function-15 revealed that the patients had deteriorated 3 months after surgery but had recovered only slightly by 6 months.

CONCLUSIONS

Laparoscopic surgery achieves feasible long-term oncological outcomes and a high rate of anus preservation with moderate anal function, and an acceptable incontinence score. While urinary function recovered rapidly, sexual function showed poor recovery.

Outcomes of Metastatic and Unresectable Small Bowel Adenocarcinoma in Japan According to the Treatment Strategy: A Nationwide Observational Study

PURPOSE

Limited information is available regarding the characteristics and outcomes of stage IV small bowel adenocarcinoma (SBA) in Japan. This study examined the clinical and pathological characteristics and outcomes according to the treatment strategies in patients with stage IV SBA.

METHODS

This retrospective observational study used the data of patients with jejunal or ileal adenocarcinoma collected by the Small Bowel Malignant Tumor Project of the Japanese Society for Cancer of the Colon and Rectum. Descriptive statistics were expressed as the mean (standard deviation) or median (range). Survival analysis was performed using Kaplan-Meier curves and pairwise log-rank tests.

RESULTS

Data from 128 patients were analyzed. The treatment strategies were chemotherapy alone (26 of 128, 20.3%), surgery alone (including palliative surgery; 21 of 128, 16.4%), surgery + chemotherapy (74 of 128, 57.8%), and best supportive care (7 of 128, 5.5%). The median (range) overall survival was 16 (0-125) months overall, and 11 (1-38) months, 8 (0-80) months, 18 (0-125) months, and 0 (0-1) months for the chemotherapy, surgery, surgery + chemotherapy, and best supportive care groups, respectively. Three main categories of chemotherapeutic regimen were used: a combination of fluoropyrimidine and oxaliplatin (F + Ox), fluoropyrimidine and irinotecan (F + Iri), and single-agent fluoropyrimidine. Among patients treated with chemotherapy, the median (range) OS was 16 (1-106) months overall, and 17 (1-87) months, 29 (7-39) months, and 16 (1-106) months in patients treated with fluoropyrimidine, F + Iri, and F + Ox, respectively.

CONCLUSION

Patients treated with surgery, chemotherapy, or both had a better prognosis than those who received best supportive care. Among patients who received chemotherapy, survival did not differ according to the chemotherapeutic regimen.

Effect of Remifentanil on the Tpeak-Tend Interval During Electroconvulsive Therapy

INTRODUCTION

QT interval dispersion, which reflects the regional heterogeneity of ventricular repolarization, increases during electroconvulsive therapy (ECT). Tpeak-Tend (TpTe) is considered a new marker of the transmural dispersion of ventricular repolarization (TDR). This study aimed to evaluate the effect of remifentanil on TpTe during ECT.

METHODS

Forty-two patients who were scheduled to undergo ECT with American Society of Anesthesiologists physical status I or II randomly received 0.1 μg/kg remifentanil (group R: n = 21) or saline (group C: n = 21). After the induction of general anesthesia, we measured the TpTe, TpTe/QT, TpTe/QTc, TpTe/RR, TpTe/√RR and TpTe/3√RR every minute during ECT (QT: QT interval, QTc: corrected QT interval, RR: RR interval). Statistical analysis was performed using two-way analysis of variance (ANOVA).

RESULTS

Immediately (T0) and 1 min (T1) after electrical stimulation, the RRs (group C: T0; 654.2 ± 145.9 ms, T1; 657.3 ± 114.8 ms, group R: T0; 849.6 ± 249.3 ms, T1; 885.4 ± 213.6 ms, p < 0.05) were significantly increased, while systolic (group C: T0; 177.1 ± 35 mmHg, group R: T0; 129 ± 27.2 mmHg, p < 0.05) and diastolic blood pressures (group C: T0; 107.1 ± 22.4 mmHg, T1; 101.3 ± 23.2 mmHg, group R: T0; 75.4 ± 19.3 mmHg, T1; 80.6 ± 18.3 mmHg, p < 0.05) were significantly decreased in group R compared to group C. The TpTe/RR was significantly lower at T1 in group R compared to group C (group C: 101.5 ± 28.2, group R: 76.8 ± 21.8, p < 0.05). However, there was no significant difference in TpTe, TpTe/QT, TpTe/QTc, TpTe/√RR or TpTe/3√RR between the two groups throughout the study.

CONCLUSION

Pretreatment with remifentanil suppressed the increase of TpTe/RR after electrical stimulation. Our results imply that remifentanil may lead to a decrease in TDR during ECT.

TRIAL REGISTRATION

This trial was registered with the University Hospital Medical Information Network (registration number: UMIN000051958).

Combined Efficacy of Systemically Acting Diclofenac Sodium Patch and Alpha-2-Delta Calcium Channel Ligand in Chronic Low Back Pain: Subanalysis of a Phase III Study

INTRODUCTION

Chronic low back pain often comprises mixed pain types and involves multiple factors. Therefore, we hypothesized that the systemic transdermal formulation of diclofenac sodium (DF systemic patch), which is effective for nociceptive pain, and an α2δ Ca2+ channel ligand, which is effective for neuropathic pain, would have additive effects in the treatment of chronic low back pain.

METHODS

From among participants in a randomized, double-blind, placebo-controlled study of DF systemic patch (75 or 150 mg) applied once daily for 2 weeks in patients with chronic low back pain, we performed a subpopulation analysis of those who were concomitantly treated with an α2δ Ca2+ channel ligand during the study period. The efficacy endpoint was pain intensity score on a visual analog scale (VAS).

RESULTS

The difference (95% confidence interval) in the least square mean pain VAS score between patients in the 150-mg combination group, who were treated with 150-mg DF systemic patch and an α2δ Ca2+ channel ligand (n = 11), and those in the non-combination group, who were treated with placebo patch and α2δ Ca2+ channel ligand (n = 22), was - 15.09 mm (- 26.45, - 3.73). Because the upper limit of the 95% confidence interval was less than zero, this result indicates that the pain VAS score improved more in the 150-mg combination group than in the non-combination group (placebo group).

CONCLUSIONS

The combination of the DF systemic patch and an α2δ Ca2+ channel ligand may be more effective than α2δ Ca2+ channel ligand monotherapy for controlling chronic low back pain.

TRIAL REGISTRATION NUMBERS

JPRN-JapicCTI-205134 and jRCT2080225040.

Specialty-Certified Colorectal Surgeons Demonstrate Favorable Short-term Surgical Outcomes for Laparoscopic Low Anterior Resection: Assessment of a Japanese Nationwide Database

BACKGROUND

There are few studies on the impact of a colorectal-specific technically certified surgeon on good surgical outcomes for laparoscopic low anterior resection in the real world.

OBJECTIVE

To evaluate the short-term outcomes of laparoscopic low anterior resection with the participation of a certified colorectal surgeon.

DESIGN

This was a retrospective cohort study using a Japanese nationwide database.

SETTING

This study was conducted as a project for the Japan Society of Endoscopic Surgery and the Japanese Society of Gastroenterological Surgery.

PATIENTS

This study included 41,741 patients listed in the National Clinical Database who underwent laparoscopic low anterior resection performed by certified, noncertified, and colorectal-specific certified surgeons, according to the Endoscopic Surgical Skill Qualification System, from 2016 to 2018.

MAIN OUTCOME MEASURES

Operative mortality rate and anastomotic leak rate were the primary outcome measures.

RESULTS

Overall 30-day mortality and operative mortality were 0.2% and 0.3%, respectively, without significant differences between all kinds of certified and noncertified surgeon groups. Overall anastomotic leak rate was 9.3%, with a significant difference between the 2 groups. Colorectal- and stomach-certified groups had lower 30-day mortality and operative mortality than the biliary-certified and noncertified groups. The anastomotic leak rate was the lowest in the colorectal-certified group. Based on a logistic regression analysis using the risk-adjusted model, operative mortality was significantly higher in the biliary-certified group than in the colorectal-certified group. Moreover, anastomotic leak rate was significantly lower in the colorectal-certified group than in the stomach-certified and noncertified groups.

LIMITATIONS

This study was a retrospective study, and there was a possibility of different definitions of anastomotic leak due to the use of a nationwide database.

CONCLUSIONS

The participation of a colorectal-specific certified surgeon may decrease the risk of operative mortality and anastomotic leak for laparoscopic low anterior resection.

CIRUJANO COLORRECTAL ALTAMENTE CALIFICADO PROVOCA RESULTADOS QUIRRGICOS FAVORABLES A CORTO PLAZO PARA LA RESECCIN ANTERIOR BAJA LAPAROSCPICA EVALUACIN DE LA BASE DE DATOS NACIONAL JAPONESA

ANTECEDENTES:Hay pocos estudios sobre el impacto de un cirujano certificado técnicamente especializado en cáncer colorrectal con un buen resultado quirúrgico para la resección anterior baja laparoscópica en el mundo real.OBJETIVO:Evaluar los resultados a corto plazo de la resección anterior baja laparoscópica con la participación de un cirujano colorrectal certificado.DISEÑO:Este fue un estudio de cohorte retrospectivo que utilizó una base de datos nacional japonesa.AJUSTE:Este estudio se realizó como un proyecto para la Sociedad Japonesa de Cirugía Endoscópica y la Sociedad Japonesa de Cirugía Gastroenterológica.PACIENTES:este estudio incluyó a 41 741 pacientes incluidos en la base de datos clínica nacional que se sometieron a una resección anterior baja laparoscópica realizada por cirujanos certificados, no certificados y certificados específicamente colorrectales, según el Sistema de calificación de habilidades quirúrgicas endoscópicas de 2016 a 2018.PRINCIPALES MEDIDAS DE RESULTADO:La tasa de mortalidad operatoria y la tasa de fuga anastomótica fueron los resultados primarios.RESULTADOS:La mortalidad general a los 30 días y la mortalidad operatoria fueron del 0,2 % y el 0,3 %, respectivamente, sin diferencias significativas entre los grupos de todos los tipos de cirujanos certificados y no certificados. La tasa global de fuga anastomótica fue del 9,3 %, con una diferencia significativa entre los dos grupos. Los grupos con certificación colorrectal y estomacal tuvieron una mortalidad a los 30 días y una mortalidad operatoria más bajas que los grupos con certificación biliar y sin certificación. La tasa de fuga anastomótica fue la más baja en el grupo certificado colorrectal. Con base en un análisis de regresión logística utilizando el modelo ajustado por riesgo, la mortalidad operatoria fue significativamente más alta en el grupo con certificación biliar que en el grupo con certificación colorrectal. Además, la tasa de fuga anastomótica fue significativamente más baja en el grupo con certificación colorrectal que en los grupos con certificación estomacal y sin certificación.LIMITACIONES:Este estudio fue retrospectivo y existía la posibilidad de diferentes definiciones de fuga anastomótica debido al uso de una base de datos nacional.CONCLUSIONES:La participación de un cirujano certificado en video específico colorrectal puede disminuir el riesgo de mortalidad operatoria y fuga anastomótica para la resección anterior baja laparoscópica. (Traducción-Dr. Mauricio Santamaria ).

Early-onset Cervical Myelitis after COVID-19 Vaccination

A 33-year-old woman developed paresthesia in her right thumb approximately 30 minutes after receiving the BNT162b2 (Pfizer-BioNTech) severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine. The paresthesia gradually spread to her right-side limbs and trunk, and cervical magnetic resonance imaging (MRI) revealed a localized lesion in the right dorsal column. After glucocorticoid therapy, her symptoms and MRI findings improved. Although disease developing less than 24 hours after vaccination is considered an unlikely cause of immuno-associated adverse events following vaccination, we discuss the possible mechanisms involved in early-onset central nervous system inflammation after vaccination in view of preexisting immunopathological susceptibility.

Remimazolam Compared to Propofol for Total Intravenous Anesthesia with Remifentanil on the Recovery of Psychomotor Function: A Randomized Controlled Trial

INTRODUCTION

This study aimed to compare remimazolam to propofol in psychomotor recovery after total intravenous anesthesia (TIVA) using the Trieger dot test.

METHODS

Sixty-six patients who were scheduled to undergo endoscopic sinus surgery with American Society of Anesthesiologists (ASA) physical status I or II were randomly allocated to the remimazolam (group R) or propofol group (group P). In group R, all patients received flumazenil postoperatively. After discontinuation of anesthetic agents, the time to eye opening, response to verbal commands, extubation, and discharge from the operation room were measured. Psychomotor recovery was assessed using the Trieger dot test before induction and at 0, 30, 60, 90, 120, 150, and 180 min after anesthesia.

RESULTS

The time to eye opening, response to verbal commands, extubation, and discharge from the operation room were significantly longer in group P compared to group R (group P: 9.8 ± 3.2 min, 11.5 ± 3.4 min, 12.7 ± 3.4 min, 18.1 ± 4.2 min; group R: 6.5 ± 2 min, 7.3 ± 2.6 min, 8.4 ± 2.9 min, 13.2 ± 3.2 min; respectively, p < 0.05). In the Trieger dot test, the number of dots missed was significantly increased in group R compared to group P at 30, 60, 90, and 120 min after discharge from the operation room (group R: 20.5 ± 9.3, 16 ± 8.8, 14.9 ± 11.1, 14.3 ± 10.8; group P: 14.6 ± 7.8, 10 ± 7.1, 8.7 ± 7.3, 7.3 ± 5.7; respectively, p < 0.05). The maximum distance of dots missed was significantly increased in group R compared to group P at 30 min after discharge from the operation room (group R: 3.9 ± 2.8; group P: 2.7 ± 1.6; p < 0.05).

CONCLUSION

Our results suggest that remimazolam with flumazenil leads to rapid recovery following anesthesia; however, it may cause delayed psychomotor decline.

CLINICAL TRIAL REGISTRATION

This trial is registered with the University Hospital Medical Information Network (registration number UMIN000044900).

Appendiceal cancer showing a submucosal tumor-like morphology in the ascending colon on colonoscopy: a case report

Few reports have described a submucosal tumor (SMT)-like colon tumor together with appendiceal cancer. Moreover, some appendiceal tumors may exhibit a cecal protuberance. Here, we report an uncommon case of appendiceal cancer with an SMT-like tumor, which was a protuberant lesion in the ascending colon. To our knowledge, this is the first report in Japan. Our case was a 50-year-old man with an ascending colon tumor presented at our hospital for further evaluation of this lesion. This was discovered as a cystic lesion near the ascending colon on colonoscopy. Our initial diagnosis was an ascending colon SMT-like tumor, and our treatment strategy was laparoscopic resection. The differential diagnosis was appendiceal cancer or mucocele. Postoperative pathological findings led to a diagnosis of adenocarcinoma of the appendix. The postoperative course was uneventful, and the patient was followed up with computed tomography and blood sampling on an outpatient basis.

Enhanced Clinical Utility of Molecular Budding Signature as a Recurrence Risk Determinant in Stage II and III Colon Cancer Patients

BACKGROUND

A molecular budding signature (MBS), which consists of seven tumor budding-related genes, was recently presented as a prominent prognostic indicator in colon cancer (CC) using microarray data acquired from frozen specimens. This study aimed to confirm the predictive power of MBS for recurrence risk based on formalin-fixed, paraffin-embedded (FFPE) materials.

METHODS

This research utilized the same microarray data from a prior multicenter study using FFPE whole tissue sections, which retrospectively reviewed 232 stage II CC patients without adjuvant chemotherapy and 302 stage III CC patients with adjuvant chemotherapy. All patients underwent upfront curative surgery without neoadjuvant therapy between 2009 and 2012. An MBS score was calculated using the mean of log2 [each signal] of seven genes (MSLN, SLC4A11, WNT11, SCEL, RUNX2, MGAT3, and FOXC1) as described before.

RESULTS

The MBS-low group exhibited a better relapse-free survival (RFS) than the MBS-high group in stage II (P = 0.0077) and in stage III CC patients (P = 0.0003). Multivariate analyses revealed that the MBS score was an independent prognostic factor in both stage II (P = 0.0257) and stage III patients (P = 0.0022). Especially among T4, N2, or both (high-risk) stage III patients, the MBS-low group demonstrated markedly better RFS compared with the MBS-high group (P = 0.0013).

CONCLUSIONS

This study confirmed the predictive power of the MBS for recurrence risk by employing FFPE materials in stage II/III CC patients.

The clinical impact of COVID-19 on endoscopic surgery in Japan: Analysis of data from the National Clinical Database

Aim

This study aimed to evaluate the impact of the coronavirus disease (COVID-19) pandemic on elective endoscopic surgeries in Japan using the National Clinical Database.

Methods

We retrospectively analyzed the clinicopathological factors and surgical outcomes of laparoscopic cholecystectomy (LC), laparoscopic distal gastrectomy (LDG), and laparoscopic low anterior resection (LLAR) and compared the monthly numbers of each procedure performed in 2020 with those in 2018 and 2019. The degree of infection in prefectures was classified into low and high groups.

Results

In 2020, the number of LCs (except for acute cholecystitis) was 76 079 (93.0% of that in 2019), the number of LDGs was 14 271 (85.9% of that in 2019), and the number of LLARs was 19 570 (88.1% of that in 2019). Although the number of robot-assisted LDG and LLAR cases increased in 2020, the growth rate was mild compared with that in 2019. There was little difference in the number of cases in the degree of infection in the prefectures. The numbers of LC, LDG, and LLAR cases decreased from May to June and recovered gradually. In late 2020, the proportion of T4 and N2 cases of gastric cancer and the number of T4 cases of rectal cancer increased compared with those in 2019. There was little difference between the proportions of postoperative complications and mortality in the three procedures between 2019 and 2020.

Conclusion

The number of endoscopic surgeries decreased in 2020 as a result of the COVID-19 pandemic. However, the procedures were performed safely in Japan.

Genome-Wide Association Study Identifies Genetic Polymorphisms Associated with Estimated Minimum Effective Concentration of Fentanyl in Patients Undergoing Laparoscopic-Assisted Colectomy

Sensitivity to opioids varies widely among individuals. To identify potential candidate single-nucleotide polymorphisms (SNPs) that may significantly contribute to individual differences in the minimum effective concentration (MEC) of an opioid, fentanyl, we conducted a three-stage genome-wide association study (GWAS) using whole-genome genotyping arrays in 350 patients who underwent laparoscopic-assisted colectomy. To estimate the MEC of fentanyl, plasma and effect-site concentrations of fentanyl over the 24 h postoperative period were estimated with a pharmacokinetic simulation model based on initial bolus doses and subsequent patient-controlled analgesia doses of fentanyl. Plasma and effect-site MECs of fentanyl were indicated by fentanyl concentrations, estimated immediately before each patient-controlled analgesia dose. The GWAS revealed that an intergenic SNP, rs966775, that mapped to 5p13 had significant associations with the plasma MEC averaged over the 6 h postoperative period and the effect-site MEC averaged over the 12 h postoperative period. The minor G allele of rs966775 was associated with increases in these MECs of fentanyl. The nearest protein-coding gene around this SNP was DRD1, encoding the dopamine D₁ receptor. In the gene-based analysis, the association was significant for the SERP2 gene in the dominant model. Our findings provide valuable information for personalized pain treatment after laparoscopic-assisted colectomy.

New Scale Predicting Distant Recurrence in Locally Advanced Lower Rectal Cancer Patients After Neoadjuvant Chemoradiotherapy

BACKGROUND/AIM

Neoadjuvant chemoradiotherapy (nCRT) for locally advanced lower rectal cancer (LALRC) is effective in preventing locoregional recurrence; however, it is less effective for preventing distant recurrence. This study aimed to evaluate a new scale for predicting distant recurrence before administering nCRT.

PATIENTS AND METHODS

Sixty-three patients underwent nCRT for LALRC between 2009 and 2016 at the Tokyo Women's Medical University. Of these, 51 consecutive patients who underwent curative surgery were enrolled in this study. Patients with ≥cT3 status or cN-positive LALRC were classified into three groups before nCRT based on the neutrophil-to-lymphocyte ratio (NLR) and lymphocyte-to-monocyte ratio (LMR): high-risk, NLR ≥3.2 and LMR <5.0; intermediate-risk, NLR <3.2 and LMR ≥5.0 or NLR ≥3.2 and LMR <5.0; and low-risk, NLR <3.2 and LMR ≥5.0. Independent risk factors associated with distant relapse-free survival were analysed using the Cox proportional hazards model. Relapse-free survival from distant metastasis was evaluated using the log-rank test.

RESULTS

Patient characteristics and tumour-associated factors were not significantly different between the groups. Distant recurrence in the high-, intermediate-, and low-risk groups was 61.5%, 42.9%, and 20.8% (p=0.046), respectively. In the multivariate analysis, the new scale was an independent risk factor for distant relapse-free survival (high-risk vs. low-risk groups, p=0.004 and intermediate-risk vs. low-risk groups, p=0.055). The 3-year distant relapse-free survival rate in the high-, intermediate-, and low-risk groups was 38.5%, 56.3%, and 81.7% (p=0.028), respectively.

CONCLUSION

A new scale combining the pre-nCRT NLR and LMR was independently associated with distant relapse-free survival. The new scale for LALRC may aid selection for total neoadjuvant chemotherapy.

Systemically Acting Diclofenac Sodium Patch for Control of Low Back Pain: A Randomized, Double-Blind, Placebo-Controlled Study in Japan

INTRODUCTION

Nonsteroidal antiinflammatory drugs (NSAIDs) are commonly used for pain disorders such as low back pain and exist in multiple formulations; however, no systemically acting transdermal formulations are available for low back pain. Transdermal formulations can be safely administered even to patients with trouble swallowing or at risk of aspiration, and without regard to the effect of food on drug absorption. Unlike locally acting formulations, systemically acting transdermal formulations need not be applied at the target site, so dosing is simple and the burden is not on one area of the skin. A patch with the systemically acting NSAID diclofenac sodium is approved in Japan for treatment of cancer-related pain, and we hypothesized that it would be useful for controlling low back pain.

METHODS

This randomized, double-blind, placebo-controlled study aimed to evaluate the efficacy and safety of diclofenac sodium patch in Japanese patients with low back pain. Eligible patients were randomized to receive diclofenac sodium patch 75 mg or 150 mg or placebo once daily for 2 weeks. The primary endpoint was pain intensity assessed on a visual analog scale (VAS).

RESULTS

Primary analysis of the primary endpoint showed that both doses of the diclofenac sodium patch (150 mg and 75 mg) were superior to placebo in terms of absolute change from baseline in mean 3-day VAS score after 2 weeks' treatment; the mean difference between the active and placebo treatments in this variable was -5.67 [95% confidence interval (CI) -9.34 to -2.00] mm in the 150 mg group and -5.68 (95% CI -9.34 to -2.01) mm in the 75 mg group. Most adverse events were mild. No serious adverse events occurred.

CONCLUSION

In Japanese patients, diclofenac sodium patch is effective for the relief of low back pain and is well tolerated.

TRIAL REGISTRATION

JPRN number, JPRN-JapicCTI-205134.

Skill-qualified surgeons positively affect short-term outcomes after laparoscopic gastrectomy for gastric cancer: a survey of the National Clinical Database of Japan

BACKGROUND

Proficiency of the operating surgeon is one of the most critical factors potentially associated with reductions in complications and surgery-related mortality. With video-rating systems having shown potential for assessing laparoscopic surgeons' proficiency, the Endoscopic Surgical Skill Qualification System (ESSQS) was developed by the Japan Society for Endoscopic Surgery to subjectively assess the proficiency of laparoscopic surgeons by rating applicants' non-edited case videos. We conducted a study to evaluate how ESSQS skill-qualified (SQ) surgeon involvement influences short-term outcomes of laparoscopic gastrectomy performed for gastric cancer.

METHODS

Data from the National Clinical Database regarding laparoscopic distal and total gastrectomy performed for gastric cancer between January 2016 and December 2018 were analyzed. Operative mortality, defined as 30-day mortality or 90-day in-hospital mortality, and anastomotic leakage rates were compared per involvement vs. non-involvement of an SQ surgeon. Outcomes were also compared per involvement of a gastrectomy-, colectomy-, or cholecystectomy-qualified surgeon. The association between the area of qualification and operative mortality/anastomotic leakage was also analyzed with a generalized estimating equation logistic regression model used to account for patient-level risk factors and institutional differences.

RESULTS

Of 104,093 laparoscopic distal gastrectomies, 52,143 were suitable for inclusion in the study; 30,366 (58.2%) were performed by an SQ surgeon. Of 43,978 laparoscopic total gastrectomies, 10,326 were suitable for inclusion; 6501 (63.0%) were performed by an SQ surgeon. Gastrectomy-qualified surgeons outperformed non-SQ surgeons in terms of both operative mortality and anastomotic leakage. They also outperformed cholecystectomy- and colectomy-qualified surgeons in terms of operative mortality or anastomotic leakage in distal and total gastrectomy, respectively.

CONCLUSION

The ESSQS appears to discriminate laparoscopic surgeons who can be expected to achieve significantly improved gastrectomy outcomes.

A case of musical hallucinations induced by tramadol

AIM

Although tramadol has been suggested to have a higher risk of producing hallucinations than other opioids, reports of musical hallucinations are extremely rare.

CASE PRESENTATION

A 72-year-old woman came to our department complaining of auditory hallucinations. She had been diagnosed with lumbar spinal canal stenosis associated with herniated and slipped disks. Due to persistent back pain, tramadol was started, and the dose was increased to 300 mg/day. The next day, she began to hear nursery rhymes, songs of the Ministry of Education, and folk songs. The musical auditory hallucinations disappeared with the use of antipsychotics and the discontinuation of tramadol. No relapse of musical auditory hallucinations was observed after the discontinuation of antipsychotics.

CONCLUSION

Based on the clinical course, we concluded that the auditory hallucinations were musical hallucinations induced by tramadol.

[A case of primary central nervous system lymphoma with marked cauda equina enlargement]

An 80-year-old woman presented with subacute right lower limb pain and bilateral lower limb weakness. MRI of the spine showed marked cauda equina enlargement with contrast enhancement. Cerebrospinal fluid (CSF) examination showed elevated cell count, decreased glucose, and elevated protein. Cytology of the CSF showed class V, which together with B-cell clonality by flow cytometry, led to the diagnosis of primary central nervous system lymphoma (PCNSL). The patient was treated with steroid, radiation, and chemotherapy. Despite the reduction in lesion size, her neurological symptoms revealed no improvement. PCNSL with cauda equina lesions are rare and often require highly invasive cauda equina biopsy for diagnosis. In recent years, some studies reported useful CSF biomarkers, but they may have some problems. Therefore, as in this case, the combination of cytology, flow cytometry and, CSF biomarkers could be a substitute method for invasive biopsies, and contribute to the early treatment of PCNSL.

Transplantation of hybrid adipose-derived stem cell sheet with autologous peritoneum: An in vivo feasibility study

Introduction

In regenerative medicine, cell sheet engineering has various advantages, including the retention of cells at the transplantation site for a longer period and the local delivery of growth factors and cytokines. Adipose-derived stem cell (ASC) is widely used owing to their various functions such as wound healing, immunomodulation, and nerve regeneration, in addition to their ability to differentiate into adipocytes, chondrocytes, and osteoblasts. ASC sheet generated using cell sheet engineering is considered effective in preventing anastomotic leakage, a serious postoperative complication in gastrointestinal surgery. However, the ASC sheet is too soft, thin, and brittle to handle with laparoscopic forceps during the operation. Therefore, we considered using the peritoneum, which is stiff and easy to collect while operating, as an alternative support. In this study, we explored the feasibility of using the peritoneum as a support for the precise transplantation of ASC sheets during surgery.

Methods

ASCs were isolated from the subcutaneous fat of the inguinal region of Sprague-Dawley (SD) transgenic rats expressing green fluorescent protein. ASCs were cultured until passage 3, seeded in temperature-responsive culture dishes, and the resulting ASC sheet was harvested at more than 80% confluency. Non-transgenic SD rats were used for transplant experiments. The wall peritoneum was harvested from SD rats following laparotomy, and hybrid adipose-derived stem cell (HASC) sheet was prepared by laminating the peritoneum with ASC sheet. The cell sheets were transplanted on the backs of SD rats following the incision. On post-transplantation days 3 and 7, the specimens were extracted. ASC and HASC sheets were then compared macroscopically and histopathologically.

Results

HASC sheet transplantation was macroscopically and histopathologically more effective than ASC sheet transplantation. The peritoneum provided sufficient stiffness as a support for precise transplantation.

Conclusion

The newly developed HASC sheet, which combine the advantages of ASC sheet with those of the peritoneum, could be more useful for clinical application than the ASC sheet alone.

The influence of vulnerability on depression among Japanese university athletes

Objective

This study examined the estimated causal relationship between vulnerability and depressive symptoms in Japanese university athletes and how the degree of vulnerability affects depressive symptoms.

Materials and methods

In Study 1, 248 Japanese university athletes completed a continual survey from Time 1 to Time 3. In Study 2, 562 Japanese university athletes responded to another survey during the same period. Structural equation modeling was performed to estimate the causal relationship using the cross-lagged effects model for the three waves. Next, a binomial logistic regression analysis was performed to examine the influence of vulnerability on depression.

Results

Results of the cross-lagged effects model showed that all paths from vulnerability to depressive symptoms were significant, and all paths from depressive symptoms to vulnerability were not significant. Thus, vulnerability was the causative variable and depressive symptoms were the outcome variables within the causal relationship. The logistic regression results showed that those with high vulnerability were 1.7 times more likely to have moderate or higher depressive symptoms than those with low vulnerability. Vulnerable individuals are at a higher risk for developing depressive symptoms. By verifying the causal relationship between vulnerability and depressive symptoms, we can contribute to the enhancement of mental health care in accordance with the weakest link model. Appropriate psychological support for athletes can decrease depression and improve their mental health.

Effect of High-radiant Emittance and Short Curing Time on Polymerization Shrinkage Vectors of Bulk Fill Composites

PURPOSE

To evaluate the effect of short curing time using a high-radiant emittance light on polymerization shrinkage vectors in different consistency bulk-fill composites (BFRCs) using micro-computed tomography.

METHODS AND MATERIALS

Radiopaque zirconia fillers were homogeneously incorporated and functioned as radiopaque tracers into two regular-paste: TBFill (Tetric EvoCeram Bulk Fill) and TPFill (Tetric PowerFill), and two flowable (n=6): TBFlow (Tetric EvoFlow Bulk Fill) and TPFlow (Tetric PowerFlow) resin composites. Class I cavities (4 mm depth × 4 mm length × 4 mm width) were 3D-printed and filled in a single increment: TBFill and TBFlow were light-activated using a Bluephase Style 20i (10 seconds in high-mode); TPFill and TPFlow were light-activated using a Bluephase PowerCure (three seconds). The same adhesive system (Adhese Universal) was used for all groups. Microcomputed tomography scans were obtained before and after light-activation. Filler particle movement was identified by polymerization shrinkage vectors at five depths (from 0-4 mm): top, top-middle, middle, middle-bottom and bottom.

RESULTS

TPFlow showed the lowest total vector displacement, followed by TBFlow, TBFill and TPFill, significantly different among each other (p<0.05). Generally, BFRCs showed decreased vector displacement with increased depth, and higher displacement at the top-surface (p<0.05). Qualitative analysis showed a similar pattern of vector magnitude and displacement for groups TBFill and TPFill, with displacement vectors on occlusal (top) surfaces toward the center of the restoration from the top to middle areas, and relatively limited displacement at the bottom. TBFlow and TPFlow showed more displacement on the occlusal (top).

CONCLUSIONS

Short curing time with high-radiant emittance on fast-curing BFRCs was shown to be a feasible option in terms of vector displacement. Flowable BFRCs presented lower vector displacement than their regular-viscosity versions.

Prognostic risk factors for pT4 colon cancer: A retrospective cohort study

The present study aimed to clarify the prognostic risk factors for pathological T4 (pT4) colon cancer and provide a basis for improved treatment in affected patients. The current retrospective cohort study included 83 consecutively enrolled patients who underwent curative surgery for primary pT4 colon cancer between January 2014 and December 2021 at Tokyo Medical Women's University (Tokyo, Japan). Oncological outcomes, including recurrence pattern, were compared between patients with pT4a and pT4b colon cancer. Independent risk factors associated with overall survival (OS) and relapse-free survival (RFS) were analyzed using a multivariate Cox regression model. The 3-year OS rates were 85.1 and 95.0% in the pT4a and pT4b groups (P=0.089) and 3-year RFS rates were 64.1 and 60.5% (P=0.589), respectively. Moreover, the 3-year peritoneal recurrence-free survival was 71.0 and 90.2% (P=0.085) in these groups, respectively. Independent risk factors for OS were histology (mucinous or poorly differentiated adenocarcinoma), tumor location (right-sided) and pN status (positive). The risk factors for RFS were histology and pN status. Patients with pT4b colon cancer and R₀ resection may not have a poorer prognosis compared with those with pT4a colon cancer. However, patients with pT4a colon cancer tended to have more peritoneal recurrence patterns. Histology and pN status were associated with OS and RFS, and right-sided colon cancer was also a risk factor for OS.

Management of inguinal lymph node metastases from rectal and anal canal adenocarcinoma

AIM

The surgical treatment of inguinal lymph node (ILN) metastases secondary to anorectal adenocarcinoma remains controversial. This study aimed to clarify the surgical treatment and management of ILN metastasis according to its classification.

METHODS

This retrospective, multi-centre, observational study included patients with synchronous or metachronous ILN metastases who were diagnosed with rectal or anal canal adenocarcinoma between January 1997 and December 2011. Treatment outcomes were analysed according to recurrence and prognosis.

RESULTS

Among 1181 consecutively enrolled patients who received treatment for rectal or anal canal adenocarcinoma at 20 referral hospitals, 76 (6.4%) and 65 (5.5%) had synchronous and metachronous ILN metastases, respectively. Among 141 patients with ILN metastasis, differentiated carcinoma, solitary ILN metastasis and ILN dissection were identified as independent predictive factors associated with a favourable prognosis. No significant difference was found in the frequency of recurrence after ILN dissection between patients with synchronous (80.6%) or metachronous (81.0%) ILN metastases. Patients who underwent R0 resection of the primary tumour and ILN dissection had a 5-year survival rate of 41.3% after ILN dissection (34.1% and 53.1% for patients with synchronous and metachronous ILN metastases, respectively, P = 0.55).

CONCLUSION

The ILN can be appropriately classified as a regional lymph node in rectal and anal canal adenocarcinoma. Moreover, aggressive ILN dissection might be effective in improving the prognosis of low rectal and anal canal adenocarcinoma with ILN metastases; thus, prophylactic ILN dissection is unnecessary.

Technical skills simulation in transplant surgery: a systematic review

Purpose

 Transplant surgery is a demanding field in which the technical skills of the surgeon correlates with patient outcomes. As such, there is potential for simulation-based training to play an important role in technical skill acquisition. This study provides a systematic assessment of the current literature regarding the use of simulation to improve surgeon technical skills in transplantation.

Methods

 Data were collected by performing an electronic search of the PubMed and Scopus database for articles describing simulation in transplant surgery. The abstracts were screened using the preferred reporting items for systematic reviews and meta-analysis (PRISMA) guidelines. Three reviewers analyzed 172 abstracts and agreed upon articles that met the inclusion criteria for the systematic review.

Results

 Simulators can be categorized into virtual reality simulators, cadaveric models, animal models (animate or inanimate) and synthetic physical models. No virtual reality simulators in transplant surgery are described in the literature. Three cadaveric models, seven animal models and eight synthetic physical models specific to transplant surgery are described. A total of 18 publications focusing on technical skills simulation in kidney, liver, lung, pancreas, and cardiac transplantation were found with the majority focusing on kidney transplantation.

Conclusions

 This systematic review identifies currently reported simulation models in transplant surgery. This will serve as a reference for general surgery and transplant surgery professionals interested in using simulation to enhance their technical skills.

Consensus statement on smoking cessation in patients with pain

Smoking is closely associated with the development of various cancers and tobacco-related illnesses such as cardiovascular and respiratory disorders. However, data are scarce on the relationship between smoking and both acute and chronic pain. In addition to nicotine, tobacco smoke contains more than 4000 different compounds. Although nicotine is not the sole cause of smoking-induced diseases, it plays a critical role in pain-related pathophysiology. Despite the acute analgesic effects of nicotine, long-term exposure leads to tolerance and increased pain sensitivity due to nicotinic acetylcholine receptor desensitization and neuronal plastic changes. The purpose of smoking cessation interventions in smoking patients with pain is primarily not only to reduce their pain and associated limitations in activities of daily living, but also to improve the outcomes of underlying pain-causing conditions and reduce the risks of tobacco-related disorders. This statement aims to summarize the available evidence on the impact of smoking on pain and to inform medical professionals of the significance of smoking cessation in patients with pain.

Aluminum potassium sulfate and tannic acid (ALTA) sclerotherapy complicating laparoscopic low anterior resection of rectal cancer: Case report

Introduction

Aluminum potassium sulfate and tannic acid (ALTA) sclerotherapy is increasingly popular for treating internal hemorrhoids. This injectable compound incites inflammation to dampen hemorrhoidal blood flow and inflict secondary fibrosis. Herein, we detail the implications of ALTA treatment for laparoscopic low anterior resection of rectal cancer.

Patient presentation

A 72-year-old man receiving ALTA sclerotherapy for internal hemorrhoids thereafter required laparoscopic low anterior resection for newly discovered early rectal cancer. Observed changes of anal canal resembled those of radiochemotherapy and proved problematic. There was mural thickening and sclerosis at the planned resection site. To ensure proper removal, the bowel was compressed and stapled slowly. A two-shot resection took place (without straining), anastomosis was performed, and a covering stoma was constructed. Recovery was uneventful, allowing discharge on postoperative Day 10. The ileostomy was closed at a later time.

Discussion

Although little information is available on long-term rectal pathology after ALTA therapy, existing data suggest that sclerosis persists well beyond injection timeframes. Hence, caution is required in dissecting and debriding sclerotic remnants. We have identified only four earlier reports in this setting, the present case providing added perspective.

Conclusion

Colonoscopy is highly advisable prior to ALTA therapy. A thorough work-up before rectal surgery is also essential, documenting any past treatments for anorectal disease, especially ALTA.

•

Rectal surgery after ALTA therapy requires caution due to mural thickening.

•

ALTA-induced tissue fibrosis is sustained for at least 5 years.

•

Careful preoperative histories of prior anorectal treatments are essential.

•

Colonoscopy is strongly recommended prior to treatment of anorectal disease.

Cost-effectiveness of 12 months of capecitabine as adjuvant chemotherapy for stage III colon cancer: preplanned cost-effectiveness analysis of the JFMC37-0801 study

OBJECTIVES

We evaluated the cost-effectiveness of a 12-month regimen of oral capecitabine versus a standard 6-month regimen as postoperative adjuvant chemotherapy for stage III colon cancer.

METHODS

We utilized patient-level data from a multi-institutional randomized controlled trial (JFMC37-0801) that investigated prolonged oral fluoropyrimidine monotherapy. The analysis considered three health states: stable disease, post-metastasis, and death. A parametric statistical model with a cure model was used to estimate the survival curve. The analysis was conducted from the Japanese public healthcare payer's perspective, considering only direct medical costs. A lifetime horizon was used, with a discount rate of 2% for both cost and health outcomes. Health outcomes were evaluated in terms of quality-adjusted life-years (QALYs).

RESULTS

The estimated cure rates for colon cancer were 0.726 [95% confidence interval (CI) 0.676-0.776] and 0.694 (95% CI 0.655-0.733) with the 12- and 6-month regimens, respectively; and the estimated 5-year relapse-free survival rates were 74.4% and 69.8%, respectively. The estimated lifetime cost for 12 months of capecitabine was JPY 3.365 million (USD 31,159), compared with JPY 3.376 million (USD 31,262) for 6 months. The estimated QALY were 12.48 and 11.77 for the 12- and 6-month regimens, respectively. Thus, the 12-month capecitabine regimen was dominant. Using a willingness-to-pay threshold of JPY 5 million per QALY, we determined a 97.4% probability that the 12-month capecitabine regimen is more cost-effective than the 6-month regimen.

CONCLUSIONS

Twelve months of capecitabine is the favorable option for postoperative adjuvant chemotherapy for stage III colon cancer from the perspective of cost-effectiveness.

Prevalence of and Risk Factors for Prescription Opioid Misuse, Abuse, Diversion and Doctor Shopping in Japan: A Survey Study

INTRODUCTION

Opioid use disorder is a global problem. Although opioid analgesics are prescribed less frequently in Japan than in many other countries, the rate of aberrant prescription opioid-taking behaviors in Japan is unknown.

METHODS

An internet survey was conducted to estimate the prevalence of and risk factors for prescription opioid misuse, abuse, diversion and doctor shopping in Japanese subjects with chronic pain who had been prescribed opioid analgesics.

RESULTS

The proportion of respondents (n = 387) who reported opioid misuse was 45.5% (95% confidence interval [CI]: 40.4-50.6); rates were: 24.6% (95% CI: 20.3-29.2) for abuse; 15.0% (95% CI: 11.6-19.0) for diversion; and 10.6% (95% CI: 7.7-14.1) for doctor shopping. Aberrant prescription opioid-taking behaviors were higher in participants with chronic post-cancer treatment pain (misuse, 64.2%; abuse, 52.2%) or chronic cancer pain (misuse, 57.4%; abuse, 26.2%) than in those with chronic noncancer pain (misuse, 37.8%; abuse, 17.0%). Younger age, male sex, smoking, habitual drinking, diagnosis of psychiatric disease, use of opioids other than tramadol, and use of opioids for chronic post-cancer treatment pain and chronic cancer pain were identified as risk factors for aberrant prescription opioid-taking behaviors.

CONCLUSION

Even in Japan, which has not experienced the surge in opioid consumption documented in other countries, aberrant prescription opioid-taking behaviors were observed. When prescribing opioid analgesics, universal precautions should always be taken for both cancer and non-cancer patients.

TRIAL REGISTRATION

UMIN000041788.

Japanese multicenter prospective study investigating laparoscopic surgery for locally advanced rectal cancer with evaluation of CRM and TME quality (PRODUCT trial)

Aim

In Japan, we have not been able to validate the results of laparoscopic surgery for locally advanced rectal cancer using the universal index “circumferential resection margin (CRM).” Previously, we established a semi‐opened circular specimen processing method and validated its feasibility. In the PRODUCT trial, we aimed to assess CRM in patients with locally advanced rectal cancer who underwent laparoscopic rectal resection.

Methods

This was a multicenter, prospective, observational study. Eligible patients had histologically confirmed rectal adenocarcinoma located at or below 12 cm above the anal verge with clinical stage II or III and were scheduled for laparoscopic or robotic surgery. The primary endpoint was pathological CRM. CRM ≤1 mm was defined as positive.

Results

A total of 303 patients operated on between August 2018 and January 2020 were included in the primary analysis. The number of patients with clinical stage II and III was 139 and 164, respectively. Upfront surgery was performed for 213 patients and neoadjuvant therapy for 90 patients. The median CRM was 4.0 mm (IQR, 2.1‐8.0 mm), and CRM was positive in 26 cases (8.6%). Univariate and multivariate analyses demonstrated that a predicted CRM from the mesorectal fascia of ≤1 mm on MRI was the significant factor for positive CRM (P = .0012 and P = .0045, respectively).

Conclusion

This study showed the quality of laparoscopic rectal resection based on the CRM in Japan. Preoperative MRI is recommended for locally advanced rectal cancer to prevent CRM positivity.

Impact of Endoscopic Surgical Skill Qualification on Laparoscopic Resections for Rectal Cancer in Japan: The EnSSURE Study

Objective

This cohort study investigated short- and long-term postoperative outcomes of laparoscopic procedures for rectal cancer performed with versus without certified surgeons.

Background

In Japan, the Endoscopic Surgical Skill Qualification System (ESSQS) evaluates surgical skills deemed essential for laparoscopic surgery; however, it is unknown whether this certification contributes to procedural safety.

Methods

Outcomes of laparoscopic rectal resections for cStage II and III rectal cancer performed from 2014 to 2016 at 56 Japanese hospitals were retrospectively reviewed. The impact of having versus not having certified surgeons on postoperative complications and other short- and long-term outcomes were assessed. In cases with ESSQS-certified surgeons, surgeons attended surgery in the capacity of an operator, assistant, scope operator, or advisor.

Results

Overall, 3188 procedures were analyzed, with 2644 procedures performed with and 544 without ESSQS-certified surgeons. A multivariate logistic regression model showed that the adjusted odds ratio of postoperative complications after procedures performed with ESSQS-certified surgeons was 0.68 (95% confidence interval, 0.51-0.91; P = 0.009). The adjusted odds ratios for conversion and pathological R0 resection rates with ESSQS-certified surgeons were 0.20 (P < 0.001) and 2.10 (P = 0.04), respectively. Multiple linear regression analyses showed significantly shorter surgical duration and more harvested lymph nodes for operations performed with ESSQS-certified surgeons. Multivariate Cox regression showed that the adjusted hazard ratios for poor overall and recurrence-free survival after operations performed with ESSQS-certified surgeons were 0.88 (P = 0.35) and 1.04 (P = 0.71), respectively.

Conclusions

This study showed the superiority of the short-term postoperative results for laparoscopic rectal procedures performed with ESSQS-certified surgeons.

OP0008 A NOVEL SITE-SPECIFIC PEGYLATED IL-2 WITH POTENT AND TREG-SELECTIVE ACTIVITY IN VIVO

Background

Decreased regulatory T cells (Tregs) and Treg dysfunction are hallmarks of a various autoimmune and inflammatory diseases. While low-dose IL-2 therapy induces Treg expansion in vivo and has clinical benefits in some diseases (e.g., SLE and chronic graft-versus-host disease [GvHD]), there are many concerns about adverse events due to low Treg-selectivity. Furthermore, frequent dosing is needed due to the short half-life.

Objectives

We discovered a novel site-specific PEGylated IL-2 variant, KKC80, with high Treg selectivity and a long half-life in vivo, which overcomes the issues of low-dose IL-2 therapy.

Methods

Based on the co-crystal structure of wild-type IL-2 and its heterotrimeric receptor (PBD ID: 2ERJ), amino acid residues that were to be PEGylation sites were substituted with oAzZLys, an azide-containing lysine derivative. The PEG molecule was site-specifically attached to oAzZLys-incorporated IL-2 by copper-free click chemistry. The binding property to the IL-2 receptors were measured by surface plasmon resonance (SPR). In vitro, Treg selectivity was evaluated by the IL-2-dependent proliferation activity of Tregs and NK cells from human peripheral blood mononuclear cells (PBMCs). In vivo pharmacological activity after the single subcutaneous administration in cynomolgus monkeys was measured by changes in Treg count and Treg activation status in peripheral blood by flow cytometry. Pharmacokinetic parameters were calculated according to serum PEGylated IL-2 concentration. Efficacy in mouse xenogeneic GvHD model using human PBMC-transplanted NOG mice and in monkey DTH model were evaluated.

Results

A novel PEGylated IL-2, KKC80 (human IL-2 desA1/C125S /I129oAzZLys_W-shaped 80 kDa PEG) was discovered by optimizing the PEGylation site and PEG structure based on Treg selectivity and PK. SPR analysis showed that the binding affinity of KKC80 to CD25 was moderately decreased from wild-type IL-2, while binding affinity of KKC80 to IL-2Rβγ was remarkably decreased due to a significant change of the association rate constant. In vitro, wild-type IL-2 activated both Tregs and NK cells in the same concentration range, whereas KKC80 selectively activated Tregs. The Treg selectivity of KKC80 was comparable to another IL-2 mutein, Fc.IL-2 V91K. KKC80, but not Fc.IL-2 V91K, retained its biological activity, even in the presence of a large amount of recombinant soluble CD25, which mimicked the endogenous decoy receptor for IL-2. In monkeys, KKC80 selectively increased peripheral blood Tregs in a dose-dependent manner; the average maximum rate of increase of Treg count in animals treated with 0.01, 0.03, 0.1, 0.3 and 1 mg/kg was 1.5, 3.5, 28, 50 and 154-fold, respectively. In contrast to Tregs, the rates of increase of conventional CD4+ T, CD8+ T and NK cells were low. The Treg increase peaked on day 8 or 11 and lasted for over day 29. KKC80 showed a more sustained upregulation of functional Treg markers (e.g., Foxp3 and CD25) in comparison to Fc.IL-2 V91K. The half-life of KKC80 was calculated as 83.5 to 150 h. At high doses, inflammation-related adverse effects, including increased CRP (≥0.3 mg/kg) and deterioration of general conditions (1 mg/kg) were observed. In the mouse xenogenic GvHD model, KKC80 ameliorated GvHD symptoms and suppressed multiple tissue inflammation markers. Decreased soluble CD25 and IFN-γ were also confirmed, suggesting Treg-mediated anti-inflammatory effect by KKC80 administration were exerted in vivo. In the monkey DTH model, KKC80 suppressed skin inflammation and antibody production.

Conclusion

Among next-generation IL-2 variants, KKC80 showed a best-in-class biological profile for Treg activation. A drastic and sustained increase of Tregs with high Treg-selectivity and anti-inflammatory effects were observed in vivo. These data suggest that in comparison to current IL-2 therapy, KKC80 provides superior therapeutic index and efficacy in patients with autoimmune and inflammatory diseases.

Figure 1.

Disclosure of Interests

Masahiro Ikeda Employee of: Kyowa Kirin Co., Ltd., Shinpei Yamaguchi Employee of: Kyowa Kirin Co., Ltd., Masumi Murakami Employee of: Kyowa Kirin Co., Ltd., Shigeki Takaoka Employee of: Kyowa Kirin Co., Ltd., Yasuko Sakaguchi Employee of: Kyowa Kirin Co., Ltd., Shunki Yasui Employee of: Kyowa Kirin Co., Ltd., Kousuke Iijima Employee of: Kyowa Kirin Co., Ltd., Kenichiro Nanya Employee of: Kyowa Kirin Co., Ltd., Hideyuki Onodera Employee of: Kyowa Kirin Co., Ltd., Toru Amano Employee of: Kyowa Kirin Co., Ltd.

Optimal opioid treatment requires a consensual approach

This phase III multicenter randomized double-blind placebo-controlled comparative study evaluated the efficacy and safety of diclofenac sodium patches for the treatment of cancer pain. The study consisted of a 2-week to 4-week open-label dose-titration phase and a 4-week double-blind phase. In the double-blind phase, patients who were expected to continue treatment of cancer pain with nonopioid analgesics alone were randomized to the diclofenac sodium patch or placebo group. Once-daily diclofenac sodium patches were started at 150 mg/day (2 patches) and could be increased up to 225 mg/day (3 patches). The primary efficacy endpoint was the time to insufficient analgesic response. Statistical analysis of the double-blind phase included data from 120 patients of the diclofenac sodium patch group and 118 patients of the placebo group. Time to insufficient analgesic response was significantly longer with diclofenac sodium patches than with placebo (P = 0.0016). The hazard ratio for insufficient response for diclofenac sodium patch vs placebo was 0.459 (95% confidence interval, 0.275-0.768). Regarding sleep quality during the double-blind phase, the proportion of patients with “very good sleep” or “good sleep” in the diclofenac sodium patch and placebo groups was 90.8% and 88.1% at the start of the double-blind phase and 81.4% and 78.6% at the final assessment, respectively. The incidence of adverse events was 60.8% (73/120) in the diclofenac sodium patch group and 60.2% (71/118) in the placebo group. Once-daily diclofenac sodium patches are effective in treating cancer pain and are well tolerated.

Interpretable AI Explores Effective Components of CAD/CAM Resin Composites

High flexural strength of computer-aided manufacturing resin composite blocks (CAD/CAM RCBs) are required in clinical scenarios. However, the conventional in vitro approach of modifying materials’ composition by trial and error was not efficient to explore the effective components that contribute to the flexural strength. Machine learning (ML) is a powerful tool to achieve the above goals. Therefore, the aim of this study was to develop ML models to predict the flexural strength of CAD/CAM RCBs and explore the components that affect flexural strength as the first step. The composition of 12 commercially available products and flexural strength were collected from the manufacturers and literature. The initial data consisted of 16 attributes and 12 samples. Considering that the input data for each sample were recognized as a multidimensional vector, a fluctuation range of 0.1 was proposed for each vector and the number of samples was augmented to 120. Regression algorithms—that is, random forest (RF), extra trees, gradient boosting decision tree, light gradient boosting machine, and extreme gradient boosting—were used to develop 5 ML models to predict flexural strength. An exhaustive search and feature importance analysis were conducted to analyze the effective components that affected flexural strength. The R2 values for each model were 0.947, 0.997, 0.998, 0.983, and 0.927, respectively. The relative errors of all the algorithms were within 15%. Among the high predicted flexural strength group in the exhaustive search, urethane dimethacrylate was contained in all compositions. Filler content and triethylene glycol dimethacrylate were the top 2 features predicted by all models in the feature importance analysis. ZrSiO4 was the third important feature for all models, except the RF model. The ML models established in this study successfully predicted the flexural strength of CAD/CAM RCBs and identified the effective components that affected flexural strength based on the available data set.

Feasibility of the semi-opened method of specimen resection for a circumferential resection margin in rectal cancer surgery: a multicenter study

PURPOSE

A circumferential resection margin (CRM) > 1 mm is a surrogate marker of oncologic outcomes in rectal cancer patients. In Japan, because the mesentery is removed from the rectum, the CRM cannot be measured. This multicenter prospective study evaluates the feasibility of a resected specimen processing method that allows CRM measurement.

METHODS

Fifty patients with rectal cancer were enrolled. Resected specimens were processed as previously reported. The primary outcomes were CRM measurement and the rate of CRM positivity. The secondary outcomes were the quality of total mesorectal excision, the possibility to visualize and sample the tumor, the number of harvested lymph nodes, and comparison between the pathological CRM and preoperative mesorectal fascia (MRF) involvement. This study was registered in the University Hospital Medical Information Network (UMIN) Clinical Trials Registry under identification number UMIN000031735.

RESULTS

The CRM was measurable in all patients and found to be positive in three (6%). We confirmed tumor localization, sampled the tumor, and measured the distal margin in all patients. A median of 20 lymph nodes were harvested. The concordance rate between preoperative MRF involvement and pathological CRM status was 90%.

CONCLUSION

A semi-opened rectal specimen with transverse slicing is a feasible method for measuring the CRM.

Current Status of Endoscopic Surgery in Japan: The 15th National Survey of Endoscopic Surgery by the Japan Society for Endoscopic Surgery

In Japan, the first endoscopic surgery, a laparoscopic cholecystectomy, was performed in 1990. Since then, operative procedures have been standardized, and the safety and efficacy of endoscopic surgery have been evaluated. In accordance with the social acceptance of endoscopic surgery as a less invasive type of surgery, the number of endoscopic procedures performed has increased in all surgical domains. The Japan Society for Endoscopic Surgery (JSES) has played an important role in the development of endoscopic surgery in Japan. Notably, a technical skills certification system for surgeons was established by the JSES to train instructors on how to teach safe endoscopic surgery. Furthermore, the JSES has conducted a national survey every 2 years. In 2019, 291,792 patients underwent endoscopic surgery in all surgical domains, such as abdominal, thoracic, mammary and thyroid gland, cardiovascular, obstetrics and gynecology, urologic, orthopedic, and plastic surgery. The 15th National Survey of Endoscopic Surgery conducted by the JSES demonstrated the status of laparoscopic surgery in Japan in 2018-2019.

Multiple intestinal lymphangiomas with episodic hemorrhage requiring partial laparoscopic resection: a case report

Background

Lymphangioma is a non-epithelial tumor marked by aggregates of abnormally dilated lymphatics. Mesenteric occurrences account for < 1% of all cases, and < 0.05% involve the gastrointestinal tract. Most are confined to children, rarely affecting adults.

Case presentation

Herein, we describe an elderly Japanese woman with anemia, hypoalbuminemia, and episodic bleeding due to multiple intestinal lymphangiomas. Abdominal computed tomography revealed multiple low-density defects of mesentery, with areas of intermediate (T1 images) or high (T2 images) signal intensity similarly dispersed in magnetic resonance scanning sequences. Single-balloon enteroscopy was undertaken, enabling identification and tattooing of a small intestinal bleeding source. Laparoscopy-assisted resection at this site served to control related hemorrhage, removing a histologically confirmed hemolymphangioma. Having recovered uneventfully, the patient remained stable 2 months postoperatively.

Conclusions

Although rare in adults, mesenteric or gastrointestinal lymphangiomas must be considered in a setting of anemia and hypoalbuminemia. Complete resection is advantageous to improve patient symptoms, but limited resection of multiple lesions may be equally effective.

Characteristics of anal canal cancer in Japan

Anal canal cancer (ACC) has been reported to be an uncommon cancer in Japan, as in the USA, Europe, and Australia. This retrospective multi‐institutional study was conducted to clarify the characteristics of ACC in Japan. First, the histological ACC type cases treated between 1991 and 2015 were collected. A detailed analysis of the characteristics of anal canal squamous cell carcinoma (SCC) cases was then conducted. The results of the histological types revealed that of the 1781 ACC cases, 435 cases (24.4%) including seven cases of adenosquamous cell carcinomas were SCC and 1260 cases (70.7%) were adenocarcinoma. However, the most common histological type reported in the USA, Europe, and Australia is SCC. Most ACC cases are adenocarcinomas and there is a low incidence of SCC in Japan which is different from the above‐mentioned countries. Moreover, we reclassified T4 into the following two groups based on tumor size: T4a (tumor diameter of 5 cm or less) and T4b (tumor diameter of more than 5 cm). The results of the TNM classification of SCC revealed that the hazard ratio (HR) to T1 of T2, T3, T4a, and T4b was 2.45, 2.28, 2.89, and 4.97, respectively. As T4b cases had a worse prognosis than T4a cases, we propose that T4 for anal canal SCC in Japan be subclassified into T4a and T4b.

Suitable indicator of heat stress for genetic evaluation of heat tolerance in Holstein cows in Japan

Only a few, principal, weather stations in Japanese prefectures have the daily humidity records required to calculate the temperature-humidity index (THI) as a dairy cow heat-stress indicator. We compared three heat-stress indices: (1) THI calculated from daily average temperature and daily relative humidity at a principal weather station (PTHI); (2) daily average temperature at each herd's closest local weather station (TEMP); and (3) THI calculated from daily average temperature at each herd's closest local weather station and daily relative humidity at the principal weather station (HTHI). We used daily records from 532 provincial weather stations and test-day records of milk production from Days 6 to 305 post-first-calving in Holsteins to compare the indices as indicators of heat-stress effects on milk yield and somatic cell score (SCS). The models used the BLUPF90 package to analyze the effects of herd-year, calving age, days in milk, and PTHI, TEMP, or HTHI. We estimated each model's mean square error (MSE) and compared suitabilities among indices for each trait. TEMP heat-stress thresholds were ~18°C (milk yield) and 15-20°C (SCS). The MSE of the HTHI model was the smallest, but no significant differences were found among the indices for milk yield.

Safety, efficacy, and operability of a newly developed absorbable adhesion barrier (GM142) in patients with primary rectal cancer scheduled for diverting ileostomy during laparoscopic surgery: Randomized controlled trial

Aim

The aim of this study was to compare the outcomes of GM142, a newly developed gelatin film with a concave and convex structure to a commercially available conventional film, hyaluronate‐carboxymethylcellulose.

Methods

Patients with primary rectal cancer who were scheduled for diverting ileostomy during laparoscopic surgery were eligible for this study. Patients were randomized before surgery and an antiadhesion film was applied under the umbilical incision. The primary outcome was the incidence of adhesion under the midline incision confirmed by second‐look surgery for diverting ileostomy closure. The secondary outcomes were the adhesion severity score, the extent of adhesion score, the presence of intestinal obstruction, and the success of all patching.

Results

A total of 146 patients were enrolled. A total of 123 patients were included in the full analysis set. The primary outcome of “no adhesion” was observed in 66.1% in the GM142 group and 55.7% in the conventional film group. The noninferiority of GM142 to conventional film was confirmed (P = .0005). The secondary outcomes were similar between the groups. For the safety evaluation, there were no safety concerns regarding allergic reactions to gelatin or increased gelatin‐specific IgE antibody titers.

Conclusions

The noninferiority of GM142 to conventional film was shown. GM142 showed no major safety issues. The clinical safety profiles of GM142 suggested certain physiological benefits of the gelatin film as an adhesion barrier.

An Open-Label Study of the Pharmacokinetics and Tolerability of Once-a-Day Fentanyl Citrate Patch in Japanese Pediatric and Adolescent Patients with Cancer Pain

BACKGROUND

Transdermal fentanyl is not yet approved for pediatric and adolescent use in Japan.

OBJECTIVE

Serum fentanyl concentration and the safety and efficacy of once-a-day fentanyl citrate patch were investigated in pediatric and adolescent patients with cancer pain.

METHODS

In this open-label, uncontrolled study, cancer patients aged 2-19 years being treated with strong opioid analgesics were switched to fentanyl citrate patch for 2 weeks. Serum fentanyl concentration was measured at steady state, and severity of pain was evaluated.

RESULTS

Eleven patients (four patients aged 2-5 years and seven patients aged 6-19 years) were enrolled. No patient received a dose exceeding 2 mg. Mean serum fentanyl concentrations after administration of 0.5 mg, 1 mg, and 2 mg were 144 pg/mL (n = 4), 277 pg/mL (n = 3), and 2070 pg/mL (n = 4), respectively. All patients were included in the efficacy and safety analysis, but one patient was excluded from the pharmacokinetic analysis because blood was sampled on the day after blood transfusion. A subgroup analysis showed that the mean serum fentanyl concentration tended to be higher in pre-school patients (aged 2-5 years) than in school-aged and adolescent patients (aged 6-19 years) and than in reports of adult patients (aged 20 years and above) who received the same dose. No respiratory adverse events were observed, and pain was well controlled.

CONCLUSION

Fentanyl citrate patch tended to result in a higher serum fentanyl concentration in pre-school patients than in school-aged, adolescent, and adult patients who received the same dose. The patch provided adequate pain control, was well tolerated, and did not cause respiratory adverse events.

TRIAL REGISTRATION NUMBER

JPRN-JapicCTI-183909.

Superdrainage Using the Cephalic Vein Due to Unsuitable Internal Thoracic Vein for Microvascular Anastomosis in Esophageal Reconstruction Using Pedicled Jejunum

The progress and popularization of microvascular surgical techniques may improve the outcomes of esophageal reconstruction using non-gastric tube (GT) grafts. A pedicled jejunum (PJ) with microvascular anastomoses is frequently selected as a reconstructed conduit for esophageal reconstruction when the GT is unavailable, and the internal thoracic (IT) vein is frequently selected as a recipient blood vessel for microvascular anastomosis. However, the IT vein may be inadequate for microvascular anastomosis because of its absence or underdevelopment. Since it is difficult to preoperatively predict such rare cases, it becomes necessary to urgently and rapidly prepare an alternative blood vessel. Herein, we present surgical procedures for superdrainage using the cephalic vein (CeV). Due the superficial nature of the CeV, it is both easy to identify and collect sufficient length. Thus, the CeV is very useful as an urgent substitute blood vessel when the IT vein is unavailable for microvascular anastomosis in esophageal reconstruction.

Lateral pelvic lymph nodes for rectal cancer: A review of diagnosis and management

The current status and future prospects for diagnosis and treatment of lateral pelvic lymph node (LPLN) metastasis of rectal cancer are described in this review. Magnetic resonance imaging (MRI) is recommended for the diagnosis of LPLN metastasis. A LPLN-positive status on MRI is a strong risk factor for metastasis, and evaluation by MRI is important for deciding treatment strategy. LPLN dissection (LPLD) has an advantage of reducing recurrence in the lateral pelvis but also has a disadvantage of complications; therefore, LPLD may not be appropriate for cases that are less likely to have LPLN metastasis. Radiation therapy (RT) and chemoradiation therapy (CRT) have limited effects in cases with suspected LPLN metastasis, but a combination of preoperative CRT and LPLD may improve the treatment outcome. Thus, RT and CRT plus selective LPLD may be a rational strategy to omit unnecessary LPLD and produce a favorable treatment outcome.

Stage II colon cancer staging using the number of retrieved lymph nodes may be superior to current TNM staging for prognosis stratification: the Japanese study group for postoperative follow-up of colorectal cancer

PURPOSE

The purpose of the study was to compare staging of stage II colon cancer using the number of retrieved lymph nodes (RN) to current TNM staging for stratification of prognosis.

METHODS

The subjects were 6307 patients with stage II colon cancer who underwent curative resection at 24 Japanese institutions. The cutoff for the number of RN was established using Akaike information criterion (AIC) values for relapse-free survival (RFS) and overall survival (OS). Comparison of survival using TNM and T + RN (TRN) staging was performed using a Cox proportional hazards regression model.

RESULTS

AIC was lowest for 14 retrieved lymph nodes for RFS and OS. This number was used as the cutoff. In multivariate analysis, age (≥ 69), male gender, V1, CEA (> 5), pT (T4a, T4b), and RN-L were independent factors associated with RFS and OS. Six combinations of pT and RN categories were used to establish three subgroups: TRN stages IIA, IIB, and IIC. The 5-year RFS was 83.9%, 72.3%, and 71.8% in TNM stages IIA, IIB, and IIC; and 86.0%, 76.9%, and 60.3% in TRN stages IIA, IIB, and IIC. The 5-year OS was 90.0%, 81.3%, and 82.6% for the TNM stages; and 91.6%, 85.0%, and 71.9% for the TRN stages. The AIC for RFS was lower for TRN (22,318.2) than for TNM (22,390.6), and that for OS was also lower for TRN (16,285.3) than for TNM (16,355.1).

CONCLUSION

Stage II colon cancer staging using the number of retrieved lymph nodes may be superior to current TNM staging for prognosis stratification.

First experience using the Senhance surgical system in laparoscopic local gastrectomy for gastrointestinal stromal tumor

Various innovative robotic systems have been developed to improve surgery precision. The Senhance Surgical System (SSS) is a digital laparoscopic system offering eye tracking and haptic feedback. Several reports have described application of the SSS to general surgeries, including cholecystectomy and colectomy. However, use of the SSS for gastric tumor has not been reported. We experienced a case of laparoscopic local gastrectomy (LLG) for gastrointestinal stromal tumor (GIST) with the SSS. A 74-year-old man diagnosed with GIST underwent LLG with the SSS. Operation, docking, and console times were 117, 11, and 59 minutes, respectively. No perioperative complications were encountered. This study is the first to report LLG for GIST with the SSS. LLG with the SSS was safe and feasible. The SSS can use reusable forceps and contribute to reducing medical costs. The development of instruments is also progressing, and various kinds of surgery are likely to be indicated.

A multicenter, randomized, double-blind, placebo-controlled, comparative study to evaluate the efficacy and safety of newly developed diclofenac patches in patients with cancer pain

ABSTRACT

This phase III multicenter randomized double-blind placebo-controlled comparative study evaluated the efficacy and safety of diclofenac sodium patches for the treatment of cancer pain. The study consisted of a 2-week to 4-week open-label dose-titration phase and a 4-week double-blind phase. In the double-blind phase, patients who were expected to continue treatment of cancer pain with nonopioid analgesics alone were randomized to the diclofenac sodium patch or placebo group. Once-daily diclofenac sodium patches were started at 150 mg/day (2 patches) and could be increased up to 225 mg/day (3 patches). The primary efficacy endpoint was the time to insufficient analgesic response. Statistical analysis of the double-blind phase included data from 120 patients of the diclofenac sodium patch group and 118 patients of the placebo group. Time to insufficient analgesic response was significantly longer with diclofenac sodium patches than with placebo (P = 0.0016). The hazard ratio for insufficient response for diclofenac sodium patch vs placebo was 0.459 (95% confidence interval, 0.275-0.768). Regarding sleep quality during the double-blind phase, the proportion of patients with "very good sleep" or "good sleep" in the diclofenac sodium patch and placebo groups was 90.8% and 88.1% at the start of the double-blind phase and 81.4% and 78.6% at the final assessment, respectively. The incidence of adverse events was 60.8% (73/120) in the diclofenac sodium patch group and 60.2% (71/118) in the placebo group. Once-daily diclofenac sodium patches are effective in treating cancer pain and are well tolerated.

Pedunculated early colorectal cancer with nodal metastasis: a case report

Background

Pedunculated polyps are more likely to be amenable to complete resection than non-pedunculated early colorectal cancers and rarely require additional surgery. We encountered a patient with a pedunculated early colorectal cancer that consisted of poorly differentiated adenocarcinoma with lymphatic invasion. We performed an additional bowel resection and found nodal metastasis.

Case presentation

A 43-year-old woman underwent colonoscopy after a positive fecal occult blood test. The colonoscopist found a 20-mm pedunculated polyp in the descending colon and performed endoscopic resection. Histopathologic examination revealed non-solid type poorly differentiated adenocarcinoma. The lesion invaded the submucosa (3500 μm from the muscularis mucosa) and demonstrated lymphatic invasion. In spite of the early stage of this cancer, the patient was considered at high risk for nodal metastasis. She was referred to our institution, where she underwent bowel resection. Although there was no residual cancer after her endoscopic resection, a metastatic lesion was found in one regional lymph node. The patient is undergoing postoperative adjuvant chemotherapy, and there has been no evidence of recurrence 3 months after the second surgery.

Conclusions

Additional bowel resection is indicated for patients with pedunculated polyps and multiple risk factors for nodal metastasis, such as poorly differentiated adenocarcinoma and lymphatic invasion. We encountered just such a patient who did have a nodal metastasis; herein, we report her case history with a review of the literature.