Impact of combined resection of the internal iliac artery on loss of volume of the gluteus muscles after pelvic exenteration.

PURPOSE: To clarify the influence of additional internal iliac artery (IIA) resection on the loss of the gluteus muscle volume after pelvic exenteration (PE). METHODS: The subjects of this retrospective analysis were 78 patients who underwent PE with or without IIA resection (n = 44 and n = 34, respectively) between 2006 and 2018. The areas of gluteal muscles (GMs) and psoas muscles (PSMs) were calculated using CT images before and 6 months after PE, and the difference was compared. RESULTS: The volumes of the GMs and PSMs were significantly reduced after PE (P < 0.001 and P = 0.005, respectively). In the IIA resection group, the GMs were significantly reduced after surgery, but the PSMs were not. The maximum GM (Gmax) was the most atrophied among the GMs. Multivariable analysis revealed that complete IIA resection was an independent promotor of the loss of volume of the Gmax (P = 0.044). In 18 patients with unilateral IIA resection, the downsizing rate of the Gmax was significantly greater on the resected side than on the non-resected side (P = 0.008). CONCLUSIONS: The GMs and PSMs were significantly smaller after PE. Complete IIA resection reduced the Gmax area remarkably. Preservation of the superior gluteus artery is likely to help maintain Gmax size, suggesting a potential preventative measure against secondary sarcopenia.

Current status of transanal total mesorectal excision for rectal cancer and the expanding indications of the transanal approach for extended pelvic surgeries.

Transanal total mesorectal excision (taTME) has been rapidly accepted as a promising surgical approach to the distal rectum. The benefits include ease of access to the bottom of the deep pelvis linearly over a short distance in order to easily visualize the important anatomy. Furthermore, the distal resection margins can be secured under direct vision. Additionally, a two-team approach combining taTME with a transabdominal approach could decrease the operative time and conversion rate. Although taTME was expected to become more rapidly popularized worldwide, enthusiasm for it has stalled due to unfamiliar intraoperative complications, a lack of oncologic evidence from randomized trials, and the widespread use of robotic surgery. While international registries have reported favorable short- and medium-term outcomes from taTME, a Norwegian national study reported a high local recurrence rate of 9.5%. The characteristics of the recurrences included rapid, multifocal growth in the pelvis, which was quite different from recurrences following traditional transabdominal TME; thus, the Norwegian Colorectal Cancer Group reached a consensus for a temporary moratorium on the performance of taTME. To ensure acceptable baseline quality and patient safety, taTME should be performed by well-trained colorectal surgeons. Although the appropriate indications for taTME remain controversial, the transanal approach is extremely important as a means of goal setting in difficult TME cases and as an aid to the transabdominal approach in various types of extended pelvic surgeries. The benefits in transanal lateral lymph node dissection and pelvic exenteration are presented herein.

Malignant Features in Pretreatment Metastatic Lateral Lymph Nodes in Locally Advanced Low Rectal Cancer Predict Distant Metastases.

INTRODUCTION: Pretreatment enlarged lateral lymph nodes (LLN) in patients with locally advanced low rectal cancer are predictive for local recurrences after neoadjuvant (chemo)radiotherapy (n(C)RT) followed by total mesorectal excision (TME). Not much is known of the impact on oncological outcomes when in addition malignant features are present in enlarged LLN. PATIENTS AND METHODS: A multicenter retrospective cohort study was conducted at five tertiary referral centers in the Netherlands and Australia. All patients were diagnosed with locally advanced low rectal cancer with LLN on pretreatment magnetic resonance imaging (MRI) and underwent n(C)RT followed by TME. LLN were considered enlarged with a short axis of ≥ 5 mm. Malignant features were defined as nodes with internal heterogeneity and/or border irregularity. Outcomes of interest were local recurrence-free survival (LRFS), distant metastatic-free survival (DMFS), and overall survival (OS). RESULTS: Out of 115 patients, the majority was male (75%) and the median age was 64 years (range 26-85 years). Median pretreatment LLN short axis was 7 mm (range 5-28 mm), and 60 patients (52%) had malignant features. After a median follow-up of 47 months, patients with larger LLN (7 + mm) had a worse LRFS (p = 0.01) but no difference in DMFS (p = 0.37) and OS (p = 0.54) compared with patients with smaller LLN (5-6 mm). LLN patients with malignant features had no difference in LRFS (p = 0.20) but worse DMFS (p = 0.004) and OS (p = 0.006) compared with patients without malignant features in the LLN. Cox regression analysis identified LLN short axis as an independent factor for LR. Malignant features in LLN were an independent factor for DMFS. CONCLUSION: The current study suggests that pretreatment enlarged LLN that also harbor malignant features are predictive of a worse DMFS. More studies will be required to further explore the role of malignant features in LLN.

Role of resection for extrahepatopulmonary metastases of colon cancer.

BACKGROUND: Although surgical resection for liver or lung metastases of colorectal cancer has been widely accepted, the use of this approach for extrahepatopulmonary metastases remains debatable due to the systemic nature of the disease. The aim of this study was to clarify the utility of resection along with perioperative chemotherapy for patients with extrahepatopulmonary metastases of colon cancer. METHODS: This is a retrospective single-arm study at a single institution. Forty-two patients with resectable extrahepatopulmonary metastases who underwent metastasectomy with curative intent between 2009 and 2018 at Nagoya University Hospital were retrospectively analyzed. The primary outcomes measured were overall and relapse-free survival. RESULTS: The most common metastatic site was the peritoneum (n = 31), followed by the distant lymph nodes (n = 10), ovary (n = 1) and spleen (n = 1), with overlaps. Preoperative and postoperative chemotherapies were administered to 22 and 8 patients, respectively; the remaining 14 patients received surgery alone. R0 resection was achieved in 36 patients (85.7%). The 5-year overall survival and 3-year relapse-free survival rates were 58.6% and 33.8%, respectively. In the univariate analysis, R1 resection was associated with a poor relapse-free survival rate (P = 0.02). In the multivariate analysis, the absence of perioperative chemotherapy was an independent risk factor for poor overall survival rates (P = 0.02). CONCLUSIONS: Surgical resection benefited selected patients with extrahepatopulmonary metastases with favorable long-term survival outcomes. Surgery alone without systemic chemotherapy is likely to bring poor outcome; therefore, preoperative induction might be promising to keep up with chemotherapy.

Early volume loss of skeletal muscle after esophagectomy: a risk for late-onset postoperative pneumonia.

Late-onset postoperative pneumonia (LOPP) after esophagectomy is poorly understood. This study was designed to clarify the features and risk factors for this event. Patients who underwent esophagectomy for esophageal cancer between 2006 and 2016 were included. LOPP was defined as radiologically proven pneumonia that occurred over 3 months after surgery, and clinically relevant late-onset postoperative pneumonia (CR-LOPP) was defined as LOPP that required administration of oxygen and antibiotics in the hospital and/or more intensive treatment. The total psoas muscle area (TPA) was measured using preoperative and postoperative (at 3 months after surgery) computed tomography scan images. Potential risk factors for CR-LOPP were investigated. Among 175 study patients, 46 (26.3%) had LOPP, 29 (16.6%) of whom exhibited CR-LOPP with a cumulative incidence of 15.6% at 3 years and 22.4% at 5 years. Four (13.8%) of these patients died of LOPP. Univariable analysis showed that clinical stage ≥III (P = 0.005), preoperative prognostic nutritional index (PNI) <45 (P = 0.035), arrhythmia (P = 0.014), postoperative hospital stay ≥40 days (P = 0.003), and percent decrease of TPA more than 5% (P < 0.001) were associated with CR-LOPP but not early onset postoperative pneumonia. Multivariable analysis revealed that clinical stage ≥III (hazard ratio [HR] 3.01, P = 0.004), postoperative hospital stay ≥40 days (HR 2.51, P = 0.015), and percent decrease of TPA >5% (HR 9.93, P < 0.001) were independent risk factors for CR-LOPP. CR-LOPP occurred in over 20% of patients at 5 years, and early postoperative loss of TPA was a potential trigger for this delayed complication.

Stoma creation is associated with a low incidence of midline incisional hernia after colorectal surgery: the "fighting over the fascia" theory concerning the incision and stoma hole.

PURPOSE: Parastomal hernia (PH) develops more frequently than incisional hernia (IH) after colorectal surgery with stoma. This study evaluated our hypothesis that inward traction of the fascia when closing a midline incision widens the stoma hole and increases the incidence of PH. METHODS: A total of 795 patients who underwent colorectal resection between 2006 and 2016 were retrospectively analyzed. The risk classification was constructed from IH risk factors extracted from the non-stoma group. Then, the classification was extrapolated to the stoma group for predicting midline IH and PH. RESULTS: The incidence of IH was 5.3% in the stoma group and 12.5% in the non-stoma group (p = 0.005). PH developed in 19.6% of 97 patients with permanent stoma. The risk classification was able to predict PH without a significant difference but was well balanced in patients with permanent stoma; however, it failed to predict IH in the stoma group. CONCLUSION: The risk classification constructed from the non-stoma group was useful for predicting not midline IH but PH, suggesting that the stoma site was the most vulnerable for herniation. The "fighting over the fascia" theory between the midline incision and stoma hole may explain the causal relationship between the midline IH and PH.

Synthesis, characterization and application of intracellular Ag/AgCl nanohybrids biosynthesized in Scenedesmus sp. as neutral lipid inducer and antibacterial agent.

The current research focuses on the Intracellular biosynthesis of Ag/AgCl nanohybrids in microalgae, Scenedesmus sp. The effect of biosynthesis process on growth and lipid profile of cells is key element of this study. Ag/AgCl nanohybrids synthesized intracellularly were characterized by UV-Vis spectrophotometer, Powder X-Ray Diffraction (P-XRD), Scanning Electron Microscopy (SEM), High Resolution Transmission Electron Microscopy (HRTEM). 10-20 nm and 10-50 nm sized spherical shaped nanoparticles of polycrystalline nature were grown using 0.5 and 1 mM of AgNO3 precursor, respectively and Scenedesmus sp. as reducing agent. Total lipid content of the cells treated with 0.5 mM and 1 mM AgNO3 was static and found to be 43.2 ± 0.01 µg/mL and 48.2 ± 0.02 µg/mL respectively at 120 h of Ag/AgCl nanoparticles biosynthesis. FAME (Fatty Acid Methyl Ester) profile was improved due to intracellular nanoparticles biosynthesis with maximum C16:0 (palmitic acid) (35.7%) in cells treated with 0.5 mM AgNO3 used for Ag/AgCl nanohybrids synthesis. Palmitic acid in cells exposed to 0.5 mM concentration of metallic precursor increased by 75.86%. Synthesized nanoparticles were tested on four bacterial strains to establish its antibacterial efficiency showing appropriate zone of inhibition at varying concentrations. Present study efficiently demonstrates the utility of microalgae integrating nanoparticles biosynthesis and lipid accumulation.

The significance of the time to arterial perfusion in intraoperative ICG angiography during colorectal surgery.

BACKGROUND: Intraoperative indocyanine green angiography (ICG-A) is a promising tool to confirm blood supply; however, the assessment is difficult without clear demarcation. In this study, the clinical impact of the time to arterial perfusion (TAP) on anastomotic leakage (AL) was evaluated, especially in patients without ICG demarcation. METHODS: The TAP was assessed using ICG-A during colorectal surgery in 110 patients. ICG demarcation required changing the transection line, and the TAP was measured at the new stump. The patients were divided into marginal flow (MF) and direct flow (DF) groups according to the arterial route. Delayed TAP was defined as the third quartile or slower TAP in each group. RESULTS: Sixty-six patients (60%) were classified into the MF group, including 64 patients who underwent rectal or sigmoid resection with high ligation of the inferior mesenteric artery. The cut-off value of the delayed TAP in the MF group was significantly slower than that in the DF group (30 and 22 s, respectively, p < 0.001). In the entire cohort, the transection line was changed in 2 patients, resulting in no AL. Nevertheless, AL still developed in 6 patients (5.4%), 5 of whom were in the MF group, and delayed TAP was found in 5 of 6 patients. Delayed TAP was significantly associated with AL in the MF group (p = 0.046). CONCLUSIONS: In patients without ICG demarcation, delayed TAP might be helpful for predicting the high-risk patients with AL in the MF group; however, performing diverting stoma or strictly careful observation might be a realistic reaction.

The survival benefit of neoadjuvant chemotherapy for resectable colorectal liver metastases with high tumor burden score.

BACKGROUND: The indications for neoadjuvant chemotherapy (NAC) in resectable colorectal liver metastases (CRLMs) remain unclear. Tumor burden score (TBS) is a prognostic tool based on tumor size and number of tumors. However, its utility in the NAC setting for initially resectable CRLM has never been investigated. METHODS: TBS is a distance from the origin on a Cartesian plane to the coordinates (x, y) = (tumor size in centimeter, number of tumors). TBS < 3 was defined as "TBS-low", whereas TBS ≥ 3 as "TBS-high". Between 2008 and 2018, 102 patients who underwent hepatectomy for resectable CRLM were retrospectively analyzed using the Kaplan-Meier method and Cox proportional hazards regression models. RESULTS: Among the TBS-low (n = 46) and TBS-high (n = 56) groups, baseline patient characteristics were mostly similar except for TBS-related parameters. NAC was more frequently administered in the TBS-high group (p = 0.038). The overall survival (OS) rates were similar between the two groups. Subgroup analysis showed that NAC was associated with non-significantly improved 5-year OS in the TBS-high group [76.1% with NAC and 54.9% without NAC (p = 0.093)]. In multivariate analysis, NAC was an independent prognostic factor for favorable OS only in the TBS-high group, while adjuvant chemotherapy (AC) was associated with improved OS only in the TBS-low group. CONCLUSION: In patients with resectable CRLM, the TBS-high population had a survival benefit from NAC, while the TBS-low population benefited from AC. TBS may serve as an indicator for patients who will benefit from NAC.

The carcinoembryonic antigen ratio is a potential predictor of survival in recurrent colorectal cancer.

BACKGROUND: The carcinoembryonic antigen (CEA) "value" itself is often useless in patients with a normal CEA level at initial presentation and those with tumor-irrelevant elevated CEA. Although the unified marker using CEA has been desirable for recurrent tumor staging as well as for primary tumor staging, little is known concerning its relationship with the survival of patients with recurrent colorectal cancer in particular. METHODS: This retrospective historical study included patients who experienced disease relapse after curative surgery for stage I-III colorectal cancer between 2006 and 2018. A total of 129 patients with recurrent disease after curative surgery for colorectal cancer were included. We focused on the CEA "ratio" (CEA-R: the ratio of the CEA level at the time of recurrence to that measured 3 months before recurrence) and aimed to evaluate the correlation between CEA-R and survival in recurrent colorectal cancer. RESULTS: Patients with a high CEA-R (≥ 2) exhibited significantly worse 2 year survival than those with a low CEA-R (< 2) (88.1% vs. 44.9%, P < 0.001), irrespective of the CEA value before primary resection. Multivariate analyses demonstrated that the CEA-R (HR; 3.270, 95% CI 1.646-6.497, P = 0.001) was a significant prognostic factor. CONCLUSION: The CEA-R is a potential marker stratifying the survival of patients with disease relapse who exhibit aggressive biology at recurrent disease foci. As a novel marker, the CEA-R would serve as a clinical guide for tailoring treatment strategies at the time of disease relapse in patients with colorectal cancer.

A novel circular ssDNA virus of the phylum Cressdnaviricota discovered in metagenomic data from otter clams (Lutraria rhynchaena).

In this study, we present an analysis of metagenome sequences obtained from a filtrate of a siphon tissue homogenate of otter clams (Lutraria rhynchaena) with swollen-siphon disease. The viral signal was mined from the metagenomic data, and a novel circular ssDNA virus was identified. Genomic features and phylogenetic analysis showed that the virus belongs to the phylum Cressdnaviricota, which consists of viruses with circular, single-stranded DNA (ssDNA) genomes. Members of this phylum have been identified in various species and in environmental samples. The newly found virus is distantly related to the currently known members of the phylum Cressdnaviricota.

What is the impact of systemic chemotherapy for lateral lymph nodes in patients with locally advanced low rectal cancer?

PURPOSE: Systemic chemotherapy (SC) before surgery is a potential treatment to improve survival in patients with advanced rectal cancer. However, the impact of SC on lateral lymph nodes (LLNs) remains unclear. METHODS: A total of 78 patients with stage II/III low rectal cancer, who received 3-month oxaliplatin-based SC followed by LLN dissection (LLND) in principle, were analysed retrospectively. "Total lateral lymph node metastases (tLLNMs)" was defined as having either pathological LLNMs (pLLNMs) or lateral local recurrences (LLRs). Patients with the maximum short-axis size of LLNs ≥ 7 mm were classified into the swollen group (n = 21). RESULTS: In the total cohort, tLLNMs included 6 pLLNMs (7.7%) and 2 LLRs (2.6%). In the non-swollen group, no patients had pLLNMs, but one had LLR (1.8%). In the swollen group, pLLNMs and LLRs were detected in 6 (28.6%) and 1 (4.8%), respectively. The swollen group was an independent risk factor for tLLNMs (P < 0.001), leading to the significantly worse 5-year relapse-free survival (RFS) of 52.4% than the others. CONCLUSION: For patients without swollen LLNs, SC could allow for omission both of lateral irradiation and LLND. For patients with swollen LLNs, the lateral local control was favourable after SC and LLND without chemoradiotherapy (CRT); however, oxaliplatin-based SC might be insufficient to improve survival, requiring more intensive chemotherapy. CRT should be indicated according to the other risk factors of central local recurrence, although the swollen LLNs should be removed.

Pelvic exenteration associated with future renal dysfunction.

PURPOSE: This study aimed to clarify the long-term change in the renal function after pelvic exenteration (PE) and to evaluate the risk factors for any future dysfunction. METHODS: This study comprised 40 patients. A greater than 25% decline in the estimated glomerular filtration rate (eGFR) at 3 years was defined as early renal function disorder (ERFD), possibly predicting future chronic kidney disease (CKD). RESULTS: In the entire cohort, the median eGFR decreased by 23% at 3 years, and CKD developed in 50%. The patients were divided into the ERFD (n = 16) and non-ERFD (n = 24) groups. In the ERFD group, the eGFR significantly decreased by 28% during the first 1.5 years and continued to decline after that, resulting in 81.3% of patients reaching CKD, whereas it was 4% and 37.5%, respectively, in the non-ERFD group. In a growth model analysis, late urinary tract complications (UTC) and small bowel obstruction were shown to be risk factors for ERFD. CONCLUSION: Although PE was associated with a high incidence of future CKD, ERFD could predict it. Close observation of the eGFR decline over 1.5 years might be beneficial to identify ERFD patients. High-risk patients with late UTC and small bowel obstruction should, therefore, be observed carefully.

Importance of the neoadjuvant rectal (NAR) score to the outcome of neoadjuvant chemotherapy alone for locally advanced rectal cancer.

PURPOSE: The neoadjuvant rectal (NAR) score is a promising indicator of survival after preoperative chemoradiotherapy for rectal cancer. However, its effectiveness after neoadjuvant chemotherapy (NAC) alone has not been fully investigated. METHODS: We analyzed data retrospectively on 61 patients with rectal cancer, who received NAC followed by surgical resection between 2010 and 2015, and evaluated the impact of the NAR score on survival. RESULTS: The median NAR score was 14.9. Of the 61 patients, 13, 35, and 13 were classified as having NAR-low (< 8), NAR-intermediate (8-16), and NAR-high (> 16) scores, respectively. The median observation period was 49.0 months. According to the NAR score, the 3-year DFS in the NAR-low group was 100%, which was significantly better than that in the NAR-intermediate (64.8%, p = 0.041), and NAR-high (61.5%, p = 0.018) groups. When the NAR-intermediate and NAR-high groups were investigated as a single high-risk group, the 3-year DFS of the patients who received adjuvant chemotherapy was 88.7%, which was significantly better than that of the patients who did not receive adjuvant chemotherapy (53.3%, p = 0.042). CONCLUSIONS: The NAR score may predict the DFS and could serve as a favorable indicator of adjuvant chemotherapy after NAC alone.

Neoadjuvant (chemo)radiotherapy and Lateral Node Dissection: Is It Mutually Exclusive?

The importance of total mesorectal excision (TME) has been the global standard of care in patients with rectal cancer. However, there is no universal strategy for lateral lymph nodes (LLN). The treatment of the lateral compartment remains controversial and has gone to the opposite directions between Eastern and Western countries in the past decades. In the East, mainly Japan, surgeons consider LLN metastases as regional disease and have performed TME with lateral lymph node dissection (LLND) without neoadjuvant (chemo)radiotherapy ([C]RT) in patients with clinical Stage II/III rectal cancer below the peritoneal reflection. In the West, neoadjuvant radiotherapy or has been the standard, and surgeons do not perform LLND assuming the (C)RT can sterilize most lateral lymph node metastasis (LLNM). Recent evidences show that lateral nodes are the major cause of local recurrence after (C)RT plus TME, and LLND reduces local recurrence particularly from the lateral compartment. Probably a combination of the two strategies, that is, neoadjuvant (C)RT plus LLND, would be needed to improve outcomes in patients with lateral nodal disease.

Clinical value of enzyme immunoassay that detects rubella-specific immunoglobulin M immediately after disease onset.

A total of 300 patients with nucleic acid test-confirmed rubella, mostly adults, were investigated to determine the clinical value of a rubella-specific IgM test using an EIA kit. IgM titers increased after rash onset, the median IgM titer being significantly higher 3 days post-onset than on previous days (P < 0.0001). Similarly, the IgM-positive rate at 3 days post-onset (61.5%) was significantly higher than on previous days (P < 0.0001). This IgM test against rubella at 3 days or more post-disease onset provides the clinically relevant information.

De novo assembly of middle-sized genome using MinION and Illumina sequencers.

BACKGROUND: The plastid acquisition by secondary endosymbiosis is a driving force for the algal evolution, and the comparative genomics was required to examine the genomic change of symbiont. Therefore, we established a pipeline of a de novo assembly of middle-sized genomes at a low cost and with high quality using long and short reads. RESULTS: We sequenced symbiotic algae Chlorella variabilis using Oxfofrd Nanopore MinION as the long-read sequencer and Illumina HiSeq 4000 as the short-read sequencer and then assembled the genomes under various conditions. Subsequently, we evaluated these assemblies by the gene model quality and RNA-seq mapping rate. We found that long-read only assembly could not be suitable for the comparative genomics studies, but with short reads, we could obtain the acceptable assembly. On the basis of this result, we established the pipeline of de novo assembly for middle-sized algal genome using MinION. CONCLUSIONS: The genomic change during the early stages of plastid acquisition can now be revealed by sequencing and comparing many algal genomes. Moreover, this pipeline offers a solution for the assembly of various middle-sized eukaryotic genomes with high-quality and ease.

Comparative genome and transcriptome analysis of diatom, Skeletonema costatum, reveals evolution of genes for harmful algal bloom.

BACKGROUND: Diatoms play a great role in carbon fixation with about 20% of the whole fixation in the world. However, harmful algal bloom as known as red tide is a major problem in environment and fishery industry. Even though intensive studies have been conducted so far, the molecular mechanism behind harmful algal bloom was not fully understood. There are two major diatoms have been sequenced, but more diatoms should be examined at the whole genome level, and evolutionary genome studies were required to understand the landscape of molecular mechanism of the harmful algal bloom. RESULTS: Here we sequenced the genome of Skeletonema costatum, which is the dominant diatom in Japan causing a harmful algal bloom, and also performed RNA-sequencing analysis for conditions where harmful algal blooms often occur. As results, we found that both evolutionary genomic and comparative transcriptomic studies revealed genes for oxidative stress response and response to cytokinin is a key for the proliferation of the diatom. CONCLUSIONS: Diatoms causing harmful algal blooms have gained multi-copy of genes related to oxidative stress response and response to cytokinin and obtained an ability to intensive gene expression at the blooms.