Effects of preceding endoscopic treatment on laparoscopic surgery for early rectal cancer

AIM

Endoscopic treatment for rectal cancer, such as endoscopic mucosal resection and endoscopic submucosal dissection, causes inflammation, oedema and fibrosis in the surrounding tissue. However, little is known about the effect of these endoscopic therapies on salvage laparoscopic rectal surgery. The objective of this retrospective cohort study was to analyse the effect of preceding endoscopic treatment on the outcomes of laparoscopic surgery for rectal cancer.

METHOD

We analysed 53 patients who underwent laparoscopic surgery for rectal cancer with clinical Tis or T1 at our department between May 2011 and June 2019. Data from 30 patients who underwent laparoscopic surgery after preceding endoscopic treatment (Group E + S) were compared with those of 23 patients who underwent laparoscopic surgery alone (Group S).

RESULTS

There was no significant difference between the groups with respect to preoperative details. The mean operative time tended to be longer in Group E + S, and the volume of intra-operative blood loss was greater in Group E + S than in Group S (median 63 ml vs 10 ml, P = 0.049). There were no significant differences between the groups in other surgical parameters or oncological outcomes.

CONCLUSION

Laparoscopic surgery after endoscopic treatment for rectal cancer may be difficult due to an increased risk of intra-operative bleeding. Long-term prognosis after surgery was not affected by preceding endoscopic treatment in rectal cancer.

Vascular anatomy of the splenic flexure, focusing on the accessory middle colic artery and vein

AIM

Recently, the accessory middle colic artery (AMCA) has been recognized as the vessel that supplies blood to the splenic flexure. However, the positional relationship between the AMCA and inferior mesenteric vein (IMV) has not been evaluated. Herein, we aimed to evaluate the anatomy of the AMCA and the splenic flexure vein (SFV).

METHOD

Two hundred and five patients with colorectal cancer who underwent enhanced CT preoperatively were enrolled in the present study. The locations of the AMCA and IMV were evaluated, focusing on the positional relationship between the vessels and pancreas - below the pancreas or to the dorsal side of the pancreas.

RESULTS

The AMCA was observed in 74 (36.1%) patients whereas the SFV was found in 177 (86.3%) patients. The left colic artery (LCA) was the major artery accompanying the SFV in 87 (42.4%) of patients. The AMCA accompanied the SFV in 65 (32.7%) patients. In 15 (7.8%) patients, no artery accompanied the SFV. The origin of the AMCA was located on the dorsal side of the pancreas in 15 (20.3%) of these 74 patients. Similarly, the destination of the IMV was located on the dorsal side of the pancreas in 65 (31.7%) of patients.

CONCLUSION

The SFV was observed in most patients, and the LCA or AMCA was the common accompanying artery. In some patients these vessels were located on the dorsal side of the pancreas and not below it. Preoperative evaluation of this anatomy may be beneficial for lymph node dissection during left-sided hemicolectomy.

Incidence of and risk factors for lymphocele formation after lateral pelvic lymph node dissection for rectal cancer: a retrospective study

AIM

Pelvic lymphocele is a common complication that develops after pelvic lymph node dissection. The incidence of pelvic lymphocele formation has been reported to be 10.5-51% after gynaecological or urological procedures. However, no evidence has been reported thus far with regard to the development of pelvic lymphocele following lateral pelvic lymph node dissection (LPND) for low rectal cancer. The aim of this study was to investigate the incidence of and risk factors for lymphocele formation after LPND for low rectal cancer and to examine its clinical management.

METHOD

We retrospectively analysed the incidence of and risk factors for pelvic lymphocele formation after LPND for rectal cancer in our hospital between January 2012 and December 2017. We also compared the size of the lymphocele between asymptomatic and symptomatic patients by using CT volumetry and examined its clinical management.

RESULTS

A total of 30 out of 98 patients (30.8%) developed pelvic lymphocele after rectal LPND. The number of resected nodes was significantly higher in patients with a pelvic lymphocele (P < 0.01). The median volume was significantly higher in patients with symptomatic pelvic lymphocele (P = 0.011). Among the nine symptomatic patients, two underwent CT-guided drainage, one underwent transurethral ureteral stent placement and one underwent laparoscopic marsupialization.

CONCLUSION

It is essential to keep in mind the possibility of pelvic lymphocele formation during follow-up of patients who undergo LPND, and to consider an appropriate treatment when these patients are symptomatic.

[A Case of Advanced Breast Cancer with Altered Biology by Eribulin Chemotherapy]

In the treatment of advanced breast cancer, onlya few drugs confer overall survival(OS)benefit. Eribulin is a drug that was shown to extend OS in an international phase Ⅲtrial; however, the underlying mechanism is thought to involve cancer microenvironment regulation. The concept of "breast cancer subtype discordance" implies the biological changes that accompany treatment. Herein, we encountered a case of advanced breast cancer in a 54-year-old woman that showed biological changes after eribulin chemotherapy. The patient noticed a lump in her left breast and visited a nearby doctor, who referred her to our hospital for close examination and treatment. Ultrasonographyrevealed a large mass at the center of the left mammarygland and axillaryly mph node swelling. Core-needle biopsyconfirmed an invasive ductal carcinoma(ER stronglypositive, PgRnegative, HER-2 negative, Ki-67 low expression). CT findings showed multiple lung metastases. Letrozole was administered for cT4N2M1, stage Ⅳ, Luminal A, which showed progression to the left side with advances in breast cancer. Six months later, the primarytumor and axillaryly mph nodes showed progression. Subsequent treatment with eribulin was started, and partial response was obtained; however, new lymph node metastasis developed in the axilla after 11 cycles. The primary tumor and axillaryly mph nodes showed stronglypositive ER expression, were PgR-negative and HER2-positive, and showed Ki-67 low expression and HER2-positive conversion.

[A Case of Recurrent Breast Cancer Treated with Local Irradiation Using Leadless Pacemaker Implantation]

A 68-year-old woman noticed a tumor in her left breast and visited our hospital. She was diagnosed with left breast cancer cT2N2M0, stage ⅢA, and surgery was performed after the neoadjuvant chemotherapy. Although this case was indicated for radiation therapy(PMRT)after total mastectomy, postoperative radiation was not performed due to an implantable pacemaker placed in the left anterior chest. Therefore, postoperative adjuvant therapy with endocrine therapy was started. After 3 years of treatment, her left axillary lymph node was enlarged, and needle biopsy confirmed metastasis and recurrence. When local excision was performed, postoperative irradiation was deemed necessary because residual microlesions were suspected. Irradiation planning did not deny the possibility that the pacemaker in the anterior chest indwelling could become the irradia- tion range. Therefore, a leadless pacemaker was inserted, and local irradiation(50 Gy/20 Fr)was performed without complications. The next treatment is fulvestrant, and no recurrence has been observed 6months postoperatively.

MCR-ALS analysis of IR spectroscopy and XRD for the investigation of ibuprofen - nicotinamide cocrystal formation

To improve aqueous solubility, a poorly water-soluble active ingredient is classically combined with a conformer to form cocrystals. Hot melt extrusion is one preparation method for the formation of cocrystal solids. The aim of our study was to determine the optimal temperature conditions for the formation of ibuprofen and nicotinamide cocrystals using real-time infrared (IR) and X-ray diffraction (XRD) measurements. IR spectra and XRD patterns were subjected to multivariate curve resolution alternating least squares (MCR-ALS) analysis and decomposed into several components. Each component was descriptive of a specific step in the formation of the cocrystal. Cocrystal formation was followed by a separation phase between amorphous ibuprofen and crystalline nicotinamide. Our results suggest that, when using the hot melt exclusion method, careful consideration should be made towards optimizing processing temperatures in order to prevent amorphization and promote control over the process of cocrystal formation.

Sorafenib inhibits vascular endothelial cell proliferation stimulated by anaplastic thyroid cancer cells regardless of BRAF mutation status

Anaplastic thyroid cancer (ATC) is a rare refractory disease, frequently associated with BRAF mutations and aberrant vascular endothelial growth factor (VEGF) secretion. The antitumor effects of sorafenib were evaluated, and its mechanisms of action were investigated. Four human ATC cell lines were used: OCUT‑4, which possesses a BRAF mutation; OCUT‑6 and ACT‑1, which carry NRAS mutations; and OCUT‑2, which possesses mutations in BRAF and PI3KCA. The viability of Sorafenib was evaluated by MTT assay. In order to examine the inhibitory effect of Sorafenib on intracellular signal transduction, expression of mitogen‑activated protein kinase kinase was examined by western blotting. In addition, cell cycle analysis was performed using flow cytometry. The inhibitory effects of sorafenib on the growth of ATC cells and human umbilical vein endothelial cells (HUVECs) stimulated with conditioned media from ATC cells were examined. Sorafenib inhibited the viability of OCUT‑4 more effectively than other ATC cell lines; these effects may have been mediated cytostatically by suppressing mitogen‑activated protein kinase kinase phosphorylation. Conversely, similar suppression was not observed in OCUT‑6 cells, which possess an NRAS mutation. The four cell lines secreted different quantities of VEGF, and the proliferation of HUVECs was differentially stimulated by their conditioned media. Both anti‑VEGF antibody and sorafenib prevented this stimulation of proliferation. In conclusion, sorafenib more effectively inhibited RAF‑generated growth signals in ATC cells compared with signals generated by its upstream gene, RAS. ATC cells stimulated the growth of HUVECs via humoral factors, including VEGF; this effect was clearly inhibited by sorafenib. The present findings highlighted the potential of sorafenib for the treatment of ATC and provided insight into its mechanism of action.

Adenoid Cystic Carcinoma of the Breast: A Case Report

Adenoid cystic carcinomas (ACCs) are malignant tumors that most often occur in the salivary glands and bronchi, with occurrence in the breast being rare. ACCs of the breast reportedly give rise to few lymph node metastases or distant metastases and have a favorable prognosis. A 56-year-old woman with a left breast mass identified by mammographic screening was examined at our institute. Breast ultrasound revealed a sharply marginated, hypoechoic mass 12.7 × 9.4 × 8.7 mm in size in the upper outer quadrant of the left breast, and a vacuum-assisted biopsy (VAB) was performed at the mass site. Pathological examination of the VAB specimen revealed atypical cells with a cribriform growth pattern, and mucosal fluid surrounding tumor nests and within tumor ducts. The area around the tumor nests and inside of tumor ducts were also positively stained with alcian blue. These findings, we reached a pathological diagnosis of ACC. The preoperative diagnosis was stage I (cT1N0M0) triple-negative left breast cancer. Surgery consisted of breast-conserving surgery and sentinel node biopsy. The excised specimen was a 15.0 × 12.1 × 9.7 mm mass with a greyish white cut surface. Pathological examination of the excised specimen revealed a so-called adenoid cystic pattern. Results from immunohistochemical staining were identical to those from a VAB specimen, as they were estrogen receptor-negative, progesterone receptors-negative, and human epidermal growth factor receptor 2-negative, with low Ki67 expression. The final diagnosis, given the above findings, was left breast cancer (ACC) pT1N0M0 stage I triple-negative subtype.

Continuous intraoperative neuromonitoring for thyroid cancer surgery: A prospective study

Objective

We evaluated the utility of continuous intraoperative neuromonitoring (CIONM) during surgery for thyroid cancer (TC) in an educational university hospital.

Study Design

Prospective observational study.

Methods

During the period April 2016 to March 2017, 43 patients who underwent standardized surgery with CIONM were prospectively included: 5 men and 38 women, 24–87 years old (median 52 years); 23 lobectomies and 20 total thyroidectomies with node dissection were conducted. Thirty‐six operations were performed by a supervising surgeon, and seven were performed by trainees.

Results

Temporal vocal cord paresis (VCP) was identified in 9 of 63 nerves at risk (14.3%) by postoperative laryngoscopy. VCP was not related to clinical factors including the surgeon's experience or the severe nerve stress demonstrated by CIONM. A significant relation only between VCP and loss of signal (LOS) was demonstrated (P = .002). The recovery of VCP was rapid (<1 month) in patients with global injury even when LOS was demonstrated, but was prolonged in patients demonstrating obvious segmental nerve injury and LOS.

Conclusion

The present standard protocol of CIONM was useful to some extent to protect prolonged VCP, but not enough to detect every nerve stress causing VCP during TC surgery. On the other hand, CIONM is a promising method that could contribute surgical education at training hospitals enabling the instant confirmation of the procedure safely.

Levels of Evidence

3b

Nomograms predicting survival and recurrence in colonic cancer in the era of complete mesocolic excision

Background

More extensive lymphadenectomy may improve survival after resection of colonic cancer. Nomograms were created predicting overall survival and recurrence for patients who undergo D2-D3 lymph node dissection, and their validity determined.

Methods

This was a multicentre study of patients with colonic cancer who underwent resection with D2-D3 lymph node dissection in Japan. Inclusion criteria included R0 resection. A training cohort of patients operated on from 2007 to 2008 was analysed to construct prognostic models predicting survival and recurrence. Discrimination and calibration were performed using an external validation cohort from the Japanese colorectal cancer registry (procedures in 2005-2006).

Results

The training cohort consisted of 2746 patients. Predictors of survival were: age (hazard ratio (HR) 1·04), female sex (HR 0·71), depth of tumour invasion (HR 1·15, 1·22, 2·96 and 3·14 for T2, T3, T4a and T4b respectively versus T1), lymphatic invasion (HR 1·11, 1·15 and 2·95 for ly1, ly2 and ly3 versus ly0), preoperative carcinoembryonic antigen (CEA) level (HR 1·21, 1·59 and 1·99 for 5·1-10·0, 10·1-20·0 and 20·1 and over versus 0-5·0 ng/ml), number of metastatic lymph nodes (HR 1·07), number of lymph nodes examined (HR 0·98) and extent of lymphadenectomy (HR 0·23, 0·13 and 0·11 for D1, D2 and D3 versus D0). Predictors of recurrence were: female sex (HR 0·82), macroscopic type (HR 3·82, 4·56, 6·66, 7·74 and 3·22 for types I, II, III, IV and V versus type 0), depth of invasion (HR 1·25, 2·66, 5·32 and 6·43 for T2, T3, T4a and T4b versus T1), venous invasion (HR 1·43, 3·05 and 4·79 for v1, v2 and v3 versus v0), preoperative CEA level (HR 1·39, 1·43, 1·56 and 1·85 for 5·1-10·0, 10·1-20·0, 20·1-40·0 and 40·1 or more versus 0-5 ng/ml), number of metastatic lymph nodes (HR 1·07) and number of lymph nodes examined (HR 0·98). The validation cohort comprised 4446 patients. The internal and external validated Harrell's C-index values for the nomogram predicting survival were 0·75 and 0·74 respectively. Corresponding values for recurrence were 0·78 and 0·75.

Conclusion

These nomograms could predict survival and recurrence after curative resection of colonic cancer.

Obstruction is associated with perineural invasion in T3/T4 colon cancer

AIM

Perineural invasion (PNI) is a risk factor for recurrence and metastasis and consequently leads to decreased survival in patients with various malignancies. Recent studies showed that stent placement in obstructive colon cancer increases the frequency of PNI. We hypothesized that mechanical stress including obstruction itself may be associated with PNI.

METHOD

We retrospectively reviewed 496 patients with pathological T3 or T4 colon cancer who did not receive preoperative treatment. Data were collected from medical charts and pathological findings. The relationships between PNI and other clinicopathological factors were analysed using univariate and multivariate analyses.

RESULTS

PNI was observed in 239 (48%) patients. Obstruction was markedly more frequent in PNI-positive cancer (39%) than in PNI-negative cancer (24%, P = 0.0003). Multivariate analyses identified obstruction as one of the significant factors associated with PNI (OR 1.68, P = 0.028). Moreover, in 414 patients without distant metastasis who underwent complete resection, PNI was an independent factor associated with poor recurrence-free survival (hazard ratio 2.35, P = 0.003). The coexistence of PNI and obstruction resulted in greater decreases in recurrence-free survival than PNI-negative and/or non-obstructive cases.

CONCLUSION

Our results suggest that obstruction is associated with PNI and consequently contributes to an increased postoperative recurrence in colon cancer.

[A Case of Invasive Ductal Carcinoma with Paget's Disease of the Breast]

Paget's disease of the breast is usually localized in the nipple epidermis and lactiferous duct located near the nipple. Here, we report a rare case of synchronous breast carcinoma with Paget's disease and invasive ductal carcinoma. A 50-year-old woman was admitted to our hospital because of abnormalities in screening mammography findings. Ultrasonography(US) findings showed a 2.4×1.3×1.6 cm sized hypoechoic lesion in a region of the left mammary gland. Computed tomography (CT)findings did not reveal distant metastasis. Magnetic resonance imaging(MRI)revealed an approximately 2.2 cm sized irregular tumor. The pretreatment diagnosis was left non-invasive ductal carcinoma(cTisN0M0, Stage 0), and surgery was performed. The tumor was found in the range of 40.2×15.0 mm, many of which were breast ductal growth. An infiltrated image was confirmed at multiple sites, but the maximum size was 2.5×1.5 mm. Pathological findings of the main lesion revealed papillotubular carcinoma. Agglomeration of heterotypic cells with abundant cytoplasm was observed in the epidermis of the papilla. The final diagnosis was invasive breast cancer(pT1aN3M0, Stage Ⅲc, Luminal HER2)coexisting with Paget's disease.

Probing ultrafast spin-relaxation and precession dynamics in a cuprate Mott insulator with seven-femtosecond optical pulses

A charge excitation in a two-dimensional Mott insulator is strongly coupled with the surrounding spins, which is observed as magnetic-polaron formations of doped carriers and a magnon sideband in the Mott-gap transition spectrum. However, the dynamics related to the spin sector are difficult to measure. Here, we show that pump-probe reflection spectroscopy with seven-femtosecond laser pulses can detect the optically induced spin dynamics in Nd2CuO4, a typical cuprate Mott insulator. The bleaching signal at the Mott-gap transition is enhanced at ~18 fs. This time constant is attributable to the spin-relaxation time during magnetic-polaron formation, which is characterized by the exchange interaction. More importantly, ultrafast coherent oscillations appear in the time evolution of the reflectivity changes, and their frequencies (1400-2700 cm-1) are equal to the probe energy measured from the Mott-gap transition peak. These oscillations can be interpreted as the interference between charge excitations with two magnons originating from charge-spin coupling.