Improved Measurements of Muonic Helium Ground-State Hyperfine Structure at a Near-Zero Magnetic Field

Muonic helium atom hyperfine structure (HFS) measurements are a sensitive tool to test the three-body atomic system and bound-state quantum electrodynamics theory, and determine fundamental constants of the negative muon magnetic moment and mass. The world's most intense pulsed negative muon beam at the Muon Science Facility of the Japan Proton Accelerator Research Complex allows improvement of previous measurements and testing further CPT invariance by comparing the magnetic moments and masses of positive and negative muons (second-generation leptons). We report new ground-state HFS measurements of muonic helium-4 atoms at a near-zero magnetic field, performed for the first time using a small admixture of CH_{4} as an electron donor to form neutral muonic helium atoms efficiently. Our analysis gives Δν=4464.980(20)  MHz (4.5 ppm), which is more precise than both previous measurements at weak and high fields. The muonium ground-state HFS was also measured under the same conditions to investigate the isotopic effect on the frequency shift due to the gas density dependence in He with CH_{4} admixture and compared with previous studies. Muonium and muonic helium can be regarded as light and heavy hydrogen isotopes with an isotopic mass ratio of 36. No isotopic effect was observed within the current experimental precision.

[Hemorrhagic Colon Cancer with Left Atrial Thrombus Formation after Anticoagulant Therapy Discontinuation-A Case Report]

The patient was a 72-year-old female. She had been taking rivaroxaban for chronic atrial fibrillation; however, she stopped taking it due to anemia and was hospitalized urgently. A contrast-enhanced computed tomography(CT)scan showed a 30 mm mass in the ascending colon, and a colonoscopy revealed ascending colon cancer(cT3, cN0, cM0, cStage Ⅱa). The tumor was hemorrhagic and was thought to have caused the anemia. On day 6 of hospitalization, another contrast- enhanced CT scan showed a poorly contrast-enhanced area in the left atrium, and transesophageal echocardiography revealed 2 left atrial thrombi(27 mm and 17 mm). Since early induction of anticoagulation therapy was considered, an emergency open right colectomy was performed to remove the cause of the bleeding. Intravenous heparin therapy was started the day after surgery and was switched to oral apixaban therapy on the fourth postoperative day. The postoperative course was good, and she was discharged home on the 17th postoperative day. This patient had conflicting clinical problems simultaneously; however, immediate decision-making and initiation of treatment were effective.

Successful omental flap coverage repair of a rectovaginal fistula after low anterior resection: a case report

BACKGROUND

Rectovaginal fistula (RVF) is a troublesome and refractory complication after low anterior resection (LAR) for rectal cancer. An omental flap repair was performed for the RVF caused due to Crohn's disease and childbirth trauma. However, there are few cases of an omental flap repair for RVF after LAR. Herein, we present a successfully repaired case of RVF by omental flap coverage after LAR for rectal cancer.

CASE PRESENTATION

A 50-year-old female patient with advanced rectal cancer underwent laparoscopic LAR with double-stapling technique anastomosis and achieved curative resection. She complained of a stool from the vagina and was diagnosed with RVF on the postoperative day (POD) 18. Conservative therapy was ineffective. We performed laparoscopic fistula resection and direct closure of the vagina and rectum, designed the omentum that could reach the pelvis, repaired RVF by omental flap coverage, and performed transverse colostomy on POD 25. She was discharged on initial POD 48. Seven months after the initial operation, colostomy closure was administered. There was no recurrence of RVF found 1 year after the initial operation.

CONCLUSIONS

The patient achieved an omental flap coverage for RVF. We successfully performed the omental flap coverage repair in patients with RVF after the leakage of LAR. An omental flap may become an alternative treatment for muscle flap or an effective treatment for RVF.

Hepatic artery resection in distal cholangiocarcinoma

PURPOSE

This study aimed to elucidate the safety and oncological outcomes of surgery with hepatic artery resection (HAR) for patients with distal cholangiocarcinoma.

METHODS

The clinical data of patients with distal cholangiocarcinoma who underwent curative intent surgery at Hiroshima University between March 2009 and January 2021 were retrospectively analyzed. Eligible patients were classified according to the presence or absence of HAR (HAR and non-HAR group), and clinicopathological features and disease-free survival rates were compared between the two groups.

RESULTS

Among the 60 patients analyzed, eight patients had received HAR, and the remaining 52 patients had not. The rate of portal vein resection, T stage, and the number of metastasized lymph nodes in the HAR group were significantly greater than those in the non-HAR group (p < 0.001, p = 0.00695, and p = 0.0480, respectively). Postoperative severe complication was confirmed in one patient, and there were no in-hospital deaths in the HAR group. Seven of 8 patients in the HAR group showed recurrence during follow-up, and of those, six patients showed early recurrence within 1 year postoperatively. The disease-free survival time in the HAR group was significantly shorter than that in the non-HAR group (median: 7.4 m vs. 34.2 m, respectively) (p < 0.001). Multivariate analysis revealed that lymph node metastasis and HAR were significant risk factors for predicting the adverse disease-free survival time (hazard ratio (HR), 3.21; p = 0.0142; HR, 4.47; p = 0.0346, respectively).

CONCLUSIONS

Patients with distal cholangiocarcinoma who underwent surgery with HAR tended to show early recurrences, although HAR could be performed safely.

Optimal lymph-node dissection for pancreatic tail cancer

PURPOSE

The optimal range of lymph-node dissection for pancreatic tail cancer remains unclear. We investigated the location and frequency of lymph-node metastases to identify the correct range of lymph-node dissection for pancreatic tail cancer.

METHODS

We analyzed clinical data retrospectively, on patients who underwent distal pancreatectomy for resectable left-sided pancreatic cancer, between February, 2006 and March, 2021. Eligible patients were divided into two groups according to the tumor location: those with pancreatic tail cancer (Pt group) and those with pancreatic body or body and tail cancer (non-Pt group).

RESULTS

Of the 96 patients analyzed, 61 (64%) were assigned to the Pt group and 35 (36%) were assigned to the non-Pt group. Metastases to stations 7, 8, 9, 10, 11, 14, and 18 were found in 0 (0%), 0 (0%), 0 (0%), 4 (7%), 18 (30%), 2 (4%), and 10 (17%) patients in the Pt group, and in 1 (3%), 4 (12%), 2 (6%), 1 (3%), 18 (51%), 3 (9%), and 6 (17%) patients in the non-Pt group, respectively.

CONCLUSION

Lymph-node dissection at stations 7, 8, and 9 might not be necessary in patients with resectable pancreatic cancer confined to the pancreatic tail.

Prognosis following an extended duration of adjuvant gemcitabine plus S-1 chemotherapy in patients with pancreatic ductal adenocarcinoma: Analysis using inverse probability of treatment weighting

BACKGROUND/PURPOSE

The aim of this study was to assess whether the duration of adjuvant gemcitabine plus S-1 (GS) chemotherapy has any effect on survival in patients with pancreatic ductal adenocarcinoma (PDAC).

METHODS

Of the 290 patients who received adjuvant GS chemotherapy, 100 (34%) received the standard duration (20-29 weeks) and 190 (66%) received an extended duration (≥30 weeks). To reduce selection bias, the prognostic impact (recurrence-free survival [RFS] and overall survival [OS]) based on the duration of adjuvant GS chemotherapy was analyzed using inverse probability of treatment weighting (IPTW). Moreover, to reduce immortal time bias, time-dependent multivariate analyses in which implementation of adjuvant GS chemotherapy was treated as time-varying covariate was also performed.

RESULTS

Extended duration of adjuvant GS chemotherapy was significantly correlated with prolonged RFS (P < .001) and OS (P < .001) after IPTW adjustment. Time-dependent multivariate analyses revealed that extended duration of adjuvant GS chemotherapy was an independent prognostic factor for prolonged RFS (hazard ratio [HR], 0.58, P = .002) and OS (HR, 0.56, P = .005).

CONCLUSION

Extended duration (≥30 weeks) of adjuvant GS chemotherapy in patients with PDAC was associated with an improved prognosis. These findings warrant a further prospective trial on PDAC to investigate the survival benefit of extended adjuvant chemotherapy.

Long-term survival after distal pancreatectomy with celiac axis resection and hepatic artery reconstruction in the setting of locally advanced unresectable pancreatic cancer

The long-term survival of patients with locally advanced, unresectable pancreatic cancer is extremely poor. We present our experience with a 67-year-old woman who had a 40-mm mass in the body of the pancreas. Tumor infiltration reached the gastroduodenal artery, celiac artery, common hepatic artery, and splenic artery. After 10 courses of FOLFIRINOX, 2 courses of gemcitabine plus nab-paclitaxel, and 6 courses of gemcitabine alone, we performed distal pancreatectomy with celiac axis resection and hepatic artery reconstruction. The bifurcation of the gastroduodenal artery and the proper hepatic artery had to be resected, after which we created 2 anastomoses: proper hepatic-to-middle colic artery, and second jejunal-to-right gastroepiploic artery. Histopathologic examination revealed an Evans grade IIb histologic response to prior treatment and verified the R0 resection status. The patient was discharged on postoperative day 30 after treatment of a grade B pancreatic fistula and is still alive, without recurrence, more than 5 years after initiation of treatment. This patient with locally advanced, unresectable pancreatic cancer achieved long-term survival through perioperative multidisciplinary treatment, including distal pancreatectomy with celiac axis resection and hepatic artery reconstruction. This aggressive procedure could be a treatment option for patients with locally advanced, unresectable pancreatic cancer.

Preoperative risk factors for positivity of peritoneal lavage cytology in patients with pancreatic ductal adenocarcinoma in the era of neoadjuvant therapy

BACKGROUND

The preoperative risk factors for positive peritoneal lavage cytology (CY) are unknown, especially in patients who received neoadjuvant therapy. In addition, the optimal indications for staging laparoscopy (SL) are still unclear. The aim of this study was to investigate the preoperative risk factors of CY positivity in patients with pancreatic ductal adenocarcinoma (PDAC) treated with surgical resection and to determine the optimal indications for SL.

METHODS

We retrospectively analyzed 493 patients with PDAC, including 356 treated with upfront surgery and 137 treated with neoadjuvant chemotherapy (NAC). The preoperative risk factor for CY positivity was investigated along with stratification according to NAC.

RESULTS

Among the 493 patients, 36 (7.3%) were CY-positive. The CY-positive frequency in patients who received and did not receive NAC was 9 (6.6%) and 27 (7.6%), respectively. In the multivariate analyses, no independent preoperative predictive factor was found in patients who received NAC, whereas body and tail PDAC were identified as an independent risk factor for CY positivity in patients who did not receive NAC.

CONCLUSIONS

The preoperative risk factors of CY-positive PDAC are body and tail PDAC in 356 patients who did not receive NAC. However, there is no useful predictive factor for CY positivity in patients treated with NAC. Based on these results, it was difficult to determine the optimal indication for SL especially in NAC cases.

Clinicopathological features of gastric cancer after pancreaticoduodenectomy: reporting of three institutional cases and review of the global literature

PURPOSE

Gastric cancer after pancreaticoduodenectomy was firstly reported in 1995, and the number of reports about this topic has increased in the past years. This review aimed to elucidate the clinicopathological features of this disease.

METHODS

Data for 32 cases were obtained using literature search, and three cases in our institution were added.

RESULTS

Twenty cases were reported from Japan, and fifteen cases were from the Western countries (Germany: 1 case, France: 2 cases, USA: 12 cases). In Japanese and the Western cases, the most dominant indication for pancreaticoduodenectomy was distal bile duct cancer and pancreatic ductal adenocarcinoma, respectively. The most frequently applied procedure of pancreaticoduodenectomy was pylorus-preserving pancreatoduodenectomy with pancreaticogastrostomy and pancreaticoduodenectomy with pancreaticojejunostomy, respectively. The median length of time interval from pancreaticoduodenectomy to GC detection tended to be shorter in the Japanese cases (61.5 months vs. 115 months). Of all cases, thirteen (37.1%) patients with gastric cancer showed no abdominal symptoms, and eight were diagnosed at regular gastroscopy. Surgical gastrectomy was performed in 30 patients, and among them, concomitant pancreatectomy was performed in six patients. Four patients received reanastomosis of remnant pancreas using pancreaticojejunostomy. Twenty-two (73.3%) patients had undifferentiated carcinomas, and stage 1, 2, 3, and 4 cancer was identified in 14, six, six, and four patients, respectively. All eight patients who had received routine gastroscopy were T1N0M0 stage 1.

CONCLUSION

Gastric cancers after pancreaticoduodenectomy including newly reported Japanese cases and our institutional cases were reviewed to make Japanese studies available to a broader scientific audience. Further investigation is necessary to elucidate the most important carcinogens among the various potential local and systemic factors.

Impact of disintegrin and metalloproteinase domain-containing protein 12 on pancreatic ductal adenocarcinoma treated with surgical resection and perioperative chemotherapy

BACKGROUND/OBJECTIVES

A disintegrin and metalloproteinase domain-containing protein 12 (ADAM12) has been reported to influence tumor progression and chemosensitivity in human cancers. We assessed the prognostic impact of ADAM12 and its predictive value for neoadjuvant chemotherapy (NAC) in patients with pancreatic ductal adenocarcinoma (PDAC) treated with surgical resection.

METHODS

ADAM12 expression was immunohistochemically examined in 428 patients with PDAC who underwent surgical resection. The association of ADAM12 expression with clinicopathological factors and survival was also analyzed.

RESULTS

Patients with high ADAM12 expression exhibited significantly shorter median disease-free survival (DFS) (high ADAM12: 17.8 vs. low ADAM12: 37.9 months; P < 0.001) and overall survival (OS) (high ADAM12: 33.1 vs. low ADAM12: 65.0 months; P < 0.001). A multivariate analysis revealed that high ADAM12 expression was an independent risk factor for poor DFS (P < 0.001) and OS (P < 0.001) in all eligible patients. Of 100 patients who received neoadjuvant chemotherapy (NAC), high ADAM12 expression was significantly associated with poor DFS in a subset of patients treated with the nab-paclitaxel (PTX) neoadjuvant regimen (P = 0.03), whereas the prognostic value of ADAM12 was not evident in patients not treated with nab-PTX (P = 0.12).

CONCLUSIONS

A negative prognostic value of high ADAM12 expression was observed in patients with PDAC treated with surgical resection, which was enhanced in patients treated with NAC, including nab-PTX. These results suggested that ADAM12 expression can predict nab-PTX chemosensitivity in PDAC and reflect PDAC progression.

Increased clostridium difficile infection in the era of preoperative chemotherapy for pancreatic cancer

BACKGROUND

In recent trend of preoperative chemotherapy, postoperative clostridium difficile infection (CDI) might be increasing in pancreatic ductal adenocarcinoma (PDAC) patients. This study aimed to elucidate the inducement of postoperative CDI in the new era of preoperative chemotherapy.

METHODS

Eligible patients were those who received pancreaticoduodenectomy for PDAC. Patients were classified into two groups according to the presence or absence of postoperative CDI, and the independently associated factors for postoperative CDI were investigated. Additionally, eligible patients were classified using the identified associated factors, and the duration of preoperative antimicrobial administration and incidence of CDI were compared between the groups.

RESULTS

Two hundred PDAC patients were eligible for this study, and postoperative CDI was detected in 15 (7.5%) patients. Multivariate analysis revealed that preoperative biliary tract infection (BTI) and chemotherapy (Chemo) were independently associated with postoperative CDI (OR, 4.05; 95% CI, 1.25-13.1; p = 0.0200 and OR, 3.64; 95% CI, 1.14-11.6; p = 0.0209, respectively). The patients were classified into four groups according to the presence or absence of preoperative BTI and Chemo (BTI-/Chemo-, BTI-/Chemo+, BTI+/Chemo- and BTI+/Chemo + group). The median durations of preoperative antimicrobial administration were 0, 2, 8 and 15 days in each group, respectively. Postoperative CDI was detected in 3.7%, 10.0%, 10.5% and 31.3% in each group, respectively, and patients in BTI+/Chemo + group suffered CDI more frequently compared to those in BTI-/Chemo-group (p = 0.00778).

CONCLUSIONS

Preoperative BTI and chemotherapy might induce postoperative CDI for PDAC patients.

A phase II study of gemcitabine/nab-paclitaxel/S-1 combination neoadjuvant chemotherapy for patients with borderline resectable pancreatic cancer with arterial contact

BACKGROUND

The prognosis of patients with borderline resectable pancreatic cancer with arterial contact (BRPC-A) is extremely poor, and effective preoperative treatment is indispensable. We evaluated the clinical efficacy and safety of neoadjuvant chemotherapy, including gemcitabine, nab-paclitaxel and S-1 (GAS), for patients with BRPC-A.

MATERIAL AND METHODS

A multicentre, single-arm, phase II study was performed. Patients were administered 1000 mg/m² gemcitabine on day 1, 125 mg/m² nab-paclitaxel on day 1 and 60-100 mg/day S-1 on days 1-7 during a 14-day cycle. Patients were then assessed for resectability and response to treatment after six cycles. The primary end-points were 2-year overall survival (OS) rate and median OS time (trial registration: jRCTs061180045, UMIN000016630).

RESULTS

Forty-seven patients with BRPC-A were eligible for the present study. Six courses of neoadjuvant GAS regimen were completed in all eligible patients. The rate of grade III/IV toxicities occurred in 14 (30%) patients during the neoadjuvant GAS regimen. The response and disease control rates were 43% and 96%, respectively. Forty-five (96%) patients received potentially curative pancreatectomy, whereas two did not owing to disease progression. R0 resection was performed in 40 (86%) of 47 eligible patients. Eleven (24%) patients experienced postoperative major complications (>grade III), including one mortality. The 2-year OS rate and median OS time among 47 eligible patients were 70.1% and 41.0 months, respectively.

CONCLUSIONS

The neoadjuvant GAS chemotherapy regimen for BRPC-A showed good efficacy with mild toxicity, resulting in a high R0 resection rate and prolonged survival in patients with BRPC-A.

Prognostic Value of Peritoneal Lavage Cytology in Patients with Pancreatic Ductal Adenocarcinoma Stratified by the Resectability Status

BACKGROUND

The prognostic value of peritoneal lavage cytology (CY) for pancreatic ductal adenocarcinoma (PDAC) remains controversial. We assessed the prognostic impact of CY status stratified by resectability in PDAC patients treated with surgical resection.

METHODS

Clinical data from 440 patients with PDAC who underwent surgical resection were retrospectively analyzed to examine the association of CY status with clinicopathological factors and survival.

RESULTS

Positive CY status (CY+) was found in 30 patients (7%). These patients had significantly worse overall survival in both the resectable (R) (P = 0.002) and borderline resectable (BR) (P < 0.001) groups. The median survival time of CY+ patients in the R and BR groups was 25.6 and 6.7 months, respectively. Multivariate analysis revealed that CY+ was an independent prognostic factor in the BR group (P < 0.001) but not in the R group (P = 0.08). In the R group, CY+ patients who received adjuvant chemotherapy had significantly longer overall survival than those without adjuvant chemotherapy (34.3 vs. 9.8 months, respectively; P < 0.001).

CONCLUSIONS

The prognosis of CY+ patients in the BR group was extremely poor. In the R group, surgical resection combined with adjuvant chemotherapy may improve the prognosis of CY+ patients.

Neoadjuvant therapy contributes to nodal downstaging of pancreatic cancer

PURPOSE

This study aimed to assess the impact of neoadjuvant therapy (NAT) for borderline resectable or locally advanced pancreatic cancer (BR/LAPC) on the American Joint Commission on Cancer (AJCC) nodal status.

METHODS

The medical records of BR/LAPC patients who underwent surgery with curative intent were retrospectively reviewed. The nodal status was compared between patients who underwent upfront surgery (UFS) and those who received NAT. Moreover, clinicopathological factors and prognostic factors for overall survival were analyzed.

RESULTS

In all, 200 patients with BR/LAPC, 78 with UFS, and 122 with NAT were enrolled. The nodal status was significantly lower in patients after NAT than after UFS (p = 0.011). A multivariate analysis of overall survival showed that UFS (hazard ratio (HR) 1.61, p = 0.024) and N2 status (HR 2.69, p < 0.001) were independent poor prognostic factors. The median serum carbohydrate antigen (CA) 19-9 level after NAT in N2 patients was 105 U/mL, which was significantly higher than that of patients with N0 (p = 0.004) and N1 (p = 0.008) status.

CONCLUSION

Patients with BR/LAPC who underwent surgery after NAT had significantly lower N2 status and better prognosis than patients who underwent UFS. Elevated CA19-9 levels after NAT indicated a higher nodal status.

Is surgery justified for elderly patients with extrahepatic cholangiocarcinoma? Reappraisal from a viewpoint of comorbidity and organ function

PURPOSE

The benefit of surgery for older patients with extrahepatic cholangiocarcinoma (EHCC) has not been established and the differences in the general condition of younger vs. older patients remain unclear.

METHODS

Patients who underwent curative surgery for EHCC were divided into two groups according to age: those younger than 75 years old (younger group) and those aged 75 years or older (older group). We analyzed the clinical data of the two groups retrospectively.

RESULTS

Among the 116 patients analyzed, 45 (38.8%) were in the older group. Regarding comorbidity, only cardiac disease was significantly more common in the older patients; however, the cardiac function of the two groups was identical. There were no significant differences in the prevalence of kidney and lung disease, but renal function was significantly deteriorated and the incidence of the mixed ventilatory defect was significantly greater in the older group. The overall 5-year survival rates for the younger and older groups were 52.4% vs. 50.4% of all cholangiocarcinoma patients (p = 0.458), 42.4% vs. 51.3% of those with hilar cholangiocarcinoma (p = 0.718), and 69.0% vs. 49.1% of those with distal cholangiocarcinoma (p = 0.534), respectively.

CONCLUSIONS

Improved survival after surgery can be expected in well-selected older cholangiocarcinoma patients. Comorbidities were not necessarily reflected in organ function, with precise organ function assessment being more important when selecting surgical candidates.

Survival impact of distal pancreatectomy with en bloc celiac axis resection combined with neoadjuvant chemotherapy for borderline resectable or locally advanced pancreatic body carcinoma

BACKGROUND

The survival benefit associated with distal pancreatectomy with en bloc celiac axis resection (DP-CAR) for patients with borderline resectable or locally advanced pancreatic body carcinoma is controversial. The aim of this study was to evaluate the impact of DP-CAR following neoadjuvant chemotherapy on survival in patients with borderline resectable or locally advanced pancreatic body carcinoma.

METHODS

Medical records of patients with pancreatic ductal adenocarcinoma who underwent distal pancreatectomy (DP, n = 102) and DP-CAR following neoadjuvant chemotherapy (n = 32) between 2008 and 2019 were analyzed retrospectively. Short- and long-term outcomes were compared between the two groups.

RESULTS

All patients who underwent DP-CAR had tumor contact with the celiac axis. Of these, 30 patients underwent preoperative embolization of the common hepatic artery. The pretreatment tumor size of patients who underwent DP-CAR was larger (P < 0.001), and rates of blood transfusion (P = 0.003) and postoperative complications (P = 0.016) were higher in patients who underwent DP-CAR compared with patients who underwent DP. The 5-year survival rate of patients who underwent DP and DP-CAR were 50.6% and 41.1%, respectively (median survival time, 65.9 vs 37.0 months). For all 134 patients, pretreatment serum CA19-9 levels (P < 0.001), adjuvant chemotherapy (P < 0.001), and lymph node status (P = 0.035) were independent prognostic factors of overall survival by multivariate analysis.

CONCLUSIONS

DP-CAR following neoadjuvant chemotherapy for patients with borderline resectable or locally advanced pancreatic body carcinoma may bring the same survival impact as DP, despite increased morbidity.

The prognostic impact of peritoneal washing cytology for otherwise resectable extrahepatic cholangiocarcinoma patients

The clinical importance of peritoneal washing cytology (PWC) for cholangiocarcinoma patients remains unclear. The clinical data of 137 extrahepatic cholangiocarcinoma patients who received PWC and curative surgery were retrospectively analyzed. Among the 137 patients analyzed, five (3.6%) had positive PWC, and 132 (96.4%) had negative PWC. The median survival time in patients with negative PWC was 6.45 years, and the overall 1-, 2-, and 5-year survival rates were 86.5%, 75.3%, and 51.6%, respectively. The median survival time in patients with positive PWC was 2.56 years, and the overall 1-, 2-, and 5-year survival rates were 60.0%, 60.0%, and 40.0%, respectively. A multivariate analysis revealed that positive lymph node metastasis (P < 0.001), positive perineural invasion (P = 0.014) and no use of adjuvant chemotherapy (P < 0.001), but not positive PWC were independently associated with a worse overall survival. In conclusion, surgery and subsequent chemotherapy might be a therapeutic option for cholangiocarcinoma patients with positive PWC.

Identification of Preoperative Risk Factors for Poor Survival in Patients with Resectable Pancreatic Cancer Treated with Upfront Surgery

INTRODUCTION

The aim of this study was to identify preoperative risk factors for poor survival in patients with resectable pancreatic ductal adenocarcinoma (PDAC) treated with upfront surgery.

METHODS

Medical records of 268 patients with resectable PDAC defined by resectability status who underwent upfront surgery were reviewed retrospectively. Multivariate analyses were performed to identify preoperative risk factors for recurrence-free survival (RFS) and overall survival (OS). Moreover, a binary logistic regression model was built to determine preoperative independent risk factors of 2- and 3-year recurrence and survival.

RESULTS

Multivariate analyses identified CA19-9 (≥100 U/mL, p < 0.001) as an independent risk factor for poor RFS, and worse performance status (1 or 2, p = 0.03), platelet:lymphocyte ratio (<150, p = 0.04), and preoperative CA19-9 (≥100 U/mL, p < 0.001) as independent risk factors for poor OS. Moreover, preoperative CA19-9 (≥100 U/mL) was the only independent risk factor identified for 2- and 3-year recurrence and survival.

DISCUSSION/CONCLUSION

Preoperative CA19-9 (≥100 U/mL) was the most reliable preoperative predictive factor for poor survival in resectable PDAC treated with upfront surgery. These findings warrant further clinical trials investigating efficacy of neoadjuvant therapy targeting the subset of patients with resectable PDAC who have elevated preoperative CA19-9, namely, those with high risk of poor prognosis.

Pre-Transplant Marital Status and Hematopoietic Cell Transplantation Outcomes

Background

Evidence about the impact of marital status before hematopoietic cell transplantation (hct) on outcomes after hct is conflicting.

Methods

We identified patients 40 years of age and older within the Center for International Blood and Marrow Transplant Research registry who underwent hct between January 2008 and December 2015. Marital status before hct was declared as one of: married or living with a partner, single (never married), separated or divorced, and widowed. We performed a multivariable analysis to determine the association of marital status with outcomes after hct.

Results

We identified 10,226 allogeneic and 5714 autologous hct cases with, respectively, a median follow-up of 37 months (range: 1-102 months) and 40 months (range: 1-106 months). No association between marital status and overall survival was observed in either the allogeneic (p = 0.58) or autologous (p = 0.17) setting. However, marital status was associated with grades 2-4 acute graft-versus-host disease (gvhd), p < 0.001, and chronic gvhd, p = 0.04. The risk of grades 2-4 acute gvhd was increased in separated compared with married patients [hazard ratio (hr): 1.13; 95% confidence interval (ci): 1.03 to 1.24], and single patients had a reduced risk of grades 2-4 acute gvhd (hr: 0.87; 95% ci: 0.77 to 0.98). The risk of chronic gvhd was lower in widowed compared with married patients (hr: 0.82; 95% ci: 0.67 to 0.99).

Conclusions

Overall survival after hct is not influenced by marital status, but associations were evident between marital status and grades 2-4 acute and chronic gvhd. To better appreciate the effects of marital status and social support, future research should consider using validated scales to measure social support and patient and caregiver reports of caregiver commitment, and to assess health-related quality of life together with health care utilization.

Clinical Implications of Pre- and Postoperative Circulating Tumor DNA in Patients with Resected Pancreatic Ductal Adenocarcinoma

BACKGROUND

The clinical implications of pre- and postoperative KRAS-mutated circulating tumor DNA (ctDNA) present in patients with pancreatic ductal adenocarcinoma (PDAC) have remained an unresolved issue. This study sought to investigate the clinical significance of pre- and postoperative ctDNA analyses and their impact on the prognosis of PDAC patients.

METHODS

Digital droplet polymerase chain reaction detected ctDNA in pre- and postoperative plasma samples prospectively obtained from patients with resectable and borderline-resectable PDAC. Its associations with recurrence-free survival (RFS) and overall survival (OS) were analyzed. The patients were sorted according to the presence of pre- and postoperative ctDNA, and its ability to stratify prognosis was evaluated.

RESULTS

The study analyzed 97 patients. Both pre- and postoperative ctDNA were detected in 9 patients, and neither was detected in 55 patients. Whereas 15 patients harbored only preoperative ctDNA, 18 patients had only postoperative ctDNA. The multivariate analysis showed that the presence of preoperative ctDNA was associated with poorer OS (P = 0.008) and that postoperative ctDNA was not associated with either RFS or OS. Survival did not differ significantly between the patients with a positive shift in ctDNA status and those without detectable pre- or postoperative ctDNA.

CONCLUSIONS

For the patients with PDAC, the presence of preoperative ctDNA was significantly associated poor OS, whereas postoperative ctDNA was not associated with poor survival. A positive change in ctDNA did not affect patients' survival.

Clinical characteristics of initial recurrence in lung after surgical resection for pancreatic ductal adenocarcinoma

BACKGROUND

The clinical characteristic differences at the initial recurrence site after resection for pancreatic ductal adenocarcinoma (PDAC) remain unknown. We investigated the clinical characteristics in patients with lung recurrence after surgical resection and evaluated the outcome of resection for isolated lung recurrence.

METHODS

Of 442 consecutive PDAC patients who underwent surgical resection between 2002 and 2018, 229 had recurrence on imaging. Initial recurrence sites were the liver, lung, local, peritoneal, multiple organs, and others. We analyzed the clinicopathologic factors and outcomes, comparing by initial recurrence site, and investigated the outcomes of resection for isolated lung recurrence.

RESULTS

Liver recurrences were the most frequent (n = 60, 26%), followed by lung recurrence (n = 48, 21%). The interval from surgery to recurrence was significantly longer in lung recurrence (P = 0.0001). Patients with lung recurrence had significantly longer overall survival after diagnosis (P < 0.0001). Patients who underwent surgical resection of lung recurrence had a significantly prolonged overall survival rate after recurrence diagnosis (P = 0.004).

CONCLUSIONS

Patients with lung recurrence had significantly prolonged survival than those with other recurrence patterns. Resection for isolated lung recurrence represented relatively good prognosis, and possibly may be beneficial in highly-selected patients.

New surgical technique for pancreatic lithotripsy without coring-out

The Frey procedure, which involves longitudinal pancreaticojejunostomy with coring-out of the pancreatic head, is considered the ideal surgical procedure for chronic pancreatitis with pancreas head stone. Long-term relief from abdominal pain after the Frey procedure was reported to reach about 90%, and this is the most common surgical procedure for chronic pancreatitis in Japan. However, coring-out has the potential risk of severe complications such as bile duct injury, pancreatic fistula, and postoperative hemorrhage. Therefore, we introduce a new lithotripsy technique using laparoscopic coagulation shear without coring-out.

Immunohistological evaluation of mismatch repair deficiency in pancreatic ductal adenocarcinoma treated with surgical resection

BACKGROUND

The frequency and prognosis of resected deficient mismatch repair (dMMR) pancreatic ductal adenocarcinoma (PDAC) remain unclear. This study was designed to assess the frequency of dMMR and its clinicopathological relevance in Japanese patients with PDAC treated with surgical resection.

METHODS

A total of 400 consecutive patients with PDAC who underwent surgical resection at Hiroshima University were enrolled. Immunohistochemical staining with four antibodies including MLH1, MSH2, MSH6, and PMS2 was used to determine the presence of dMMR in PDAC specimens. Statistical analyses were applied to evaluate the frequency and clinical outcomes of these patients.

RESULTS

Of these 400 patients, five (1.3%) had dMMR (two had MLH1 deficiency, two had PMS2 deficiency, and one had MSH2 deficiency). We found a significantly different histological differentiation pattern between patients with dMMR and those with proficient mismatch repair (pMMR) (P = .03). Univariate survival analysis revealed no significant differences between dMMR and pMMR in recurrence-free survival (P = .268) or overall survival (P = .173).

CONCLUSIONS

The incidence of dMMR in Japanese patients with resected PDAC is low, and we found no ethnic-specific differences when comparing the incidence to that in Caucasian patients. In the current study, no significant difference was found in recurrence-free and overall survival between patients with dMMR and pMMR.

Neoadjuvant therapy for pancreatic cancer: an intention-to-treat analysis

PURPOSE

This study aimed to reassess the duration of neoadjuvant therapy (NAT) for patients with borderline resectable pancreatic cancer (BRPC).

METHODS

The medical records of patients with BRPC who received NAT before intended curative resection were retrospectively reviewed. Patient demographics, clinicopathological factors, and prognostic factors for overall survival were analyzed. The serum carbohydrate antigen (CA) 19-9 level was examined monthly during NAT.

RESULTS

A total of 118 patients with BRPC were enrolled. The median survival time and 5-year overall survival were 28.0 months and 31%, respectively. Three months after NAT, the CA19-9 levels were normal in 57% of the patients, and 92% underwent resection. Multivariate analysis showed that radiological partial response (hazard ratio (HR), 0.53; 95% confidence interval (CI), 0.26-0.99; p = 0.047); a normal CA19-9 level after NAT (HR, 0.30; 95% CI, 0.22-0.66; p = 0.006); and tumor resection (HR, 0.29; 95% CI, 0.13-0.67; p = 0.005) were independent predictors of better survival. The median CA19-9 level and the rate of normal CA19-9 levels before and after NAT were 256 (interquartile range (IQR), 23-1197) U/mL and 33%, and 27 (IQR, 7-176) U/mL and 57%, respectively.

CONCLUSION

A normal CA19-9 level after NAT was an independent predictor of better survival in patients with BRPC. A longer NAT duration might contribute to improved prognosis of patients with elevated CA19-9 levels.

Reappraisal of the validity of surgery for patients with pancreatic cancer aged 80 years or older stratified by resectability status

PURPOSE

The aim of this study was to assess the validity of surgical resection for patients with pancreatic ductal adenocarcinoma (PDAC) aged ≥80 years stratified by resectability status.

METHODS

Medical records of 245 patients with resectable (R) and 169 with borderline resectable/unresectable (BR/UR) PDAC were reviewed retrospectively. Of the total of 414 patients, 56 (14%) were ≥80 years. The prognostic impact of age ≥80 years was analyzed with stratification by resectability status.

RESULTS

No significant difference was found in the incidence of major complications between patients aged ≥80 versus <80 years (12% vs. 16% respectively; P = 0.53). However, patients aged ≥80 years were significantly less likely to receive adjuvant gemcitabine + S-1 chemotherapy than those <80 years (39% vs. 83%, respectively; P < 0.001). Multivariate analyses identified age ≥80 years as an independent risk factor for poor survival in the BR/UR group (P = 0.01), whereas it did not affect survival in the R group.

CONCLUSION

Patients aged ≥80 years had a similar prognosis to <80 years in R PDAC, whereas they had significantly worse prognosis in BR/UR PDAC. These findings suggest that surgical resection for patients with PDAC aged ≥80 years is validated in R PDAC, whereas its survival benefit might be limited in BR/UR PDAC.

A case of hepatic pseudolymphoma in a patient with primary biliary cirrhosis

Hepatic pseudolymphoma is a very rare benign reactive lymphoid hyperplasia associated with autoimmunity and chronic inflammatory liver diseases such as primary biliary cirrhosis and may mimic hepatocellular carcinoma. This diagnosis should be suspected in female with a suspicious single tumor. Close monitoring is needed in view of its premalignant nature.

Prognostic Significance of Lymph Node Metastasis and Micrometastasis Along the Left Side of Superior Mesenteric Artery in Pancreatic Head Cancer

BACKGROUNDS AND OBJECTIVES

Although metastasis in lymph nodes along the left side of superior mesenteric artery (SMA-LNs-lt) is sometimes found, survival benefit of SMA-LN-lt dissection for pancreatic head cancer is still unclear. The purpose of this study is to evaluate the prognostic significance of SMA-LN-lt metastasis and micrometastasis.

METHODS

A total of 166 patients with pancreatic head cancer who underwent pancreatectomy with lymphadenectomy including SMA-LNs-lt between 2002 and 2017 were reviewed retrospectively. Micrometastasis was evaluated by immunohistochemistry.

RESULTS

Twenty patients (12%) had SMA-LN-lt metastasis detected by hematoxylin and eosin (HE) staining, and eight patients (5%) had micrometastasis. Patients with SMA-LN-lt HE-positive or micrometastasis group experienced significantly shorter overall survival (OS) than those without (p = .015). In multivariate analysis, SMA-LN-lt HE-positive or micrometastasis (p = .034), portal vein resection (p = .002), histologic grade 2/3 (p = .046), LN metastasis (p = .002), and lack of adjuvant chemotherapy (p < .001) were independent risk factors. Within a subset of SMA-LN-lt HE-positive or micrometastasis group, lack of adjuvant chemotherapy (p = .003) was the independent poor prognostic factor.

CONCLUSIONS

In pancreatic head cancer, the rate of SMA-LN-lt HE-positive and micrometastasis was found in 12% and 5%, respectively. Adjuvant chemotherapy may contribute to improvement of prognosis in patients with LN metastasis including SMA-LN-lt metastasis and micrometastasis.

Exogenous β-mannanase supplementation improved immunological and metabolic responses in lactating dairy cows

Exogenous enzymes have been used to improve nutrient utilization in several species of livestock, particularly swine and poultry. In addition, improved immunological and metabolic traits have been reported in nonruminants. The objective of this study was to determine the effects of β-mannanase supplementation on milk yield and composition, and immunological and metabolic responses in lactating Holstein dairy cows. Two weeks after calving, 20 Holstein cows (10 multiparous and 10 primiparous) were blocked by parity and assigned to 1 of 2 diets for 182 d. All cows were housed in the same environment and fed the same basal diet. The basal diet of the treatment group was supplemented with β-mannanase (CTCBio Inc., Seoul, South Korea) at 0.1% of concentrate dry matter. No differences were detected between the control and enzyme supplement groups in milk yield parameters or milk composition. Supplementation of β-mannanase enzyme reduced blood haptoglobin levels in supplemented multiparous cows compared with controls. Furthermore, nonesterified fatty acid concentration levels tended to be lower in cows fed β-mannanase, regardless of parity. Neither immunoglobulin G nor milk somatic cell count was affected by β-mannanase supplementation, regardless of parity. The number of insemination services tended to be lower in cows fed diets supplemented with β-mannanase. Results from this study suggest that supplementation of β-mannanase exogenous enzyme could help to reduce instances of systemic inflammation and decrease fat mobilization in lactating Holstein cows. Multiparous cows are considered susceptible to acute infections and inflammation; thus, the enzyme had a greater effect in multiparous cows.

New precise measurements of muonium hyperfine structure at J-PARC MUSE

High precision measurements of the ground state hyperfine structure (HFS) of muonium is a stringent tool for testing bound-state quantum electrodynamics (QED) theory, determining fundamental constants of the muon magnetic moment and mass, and searches for new physics. Muonium is the most suitable system to test QED because both theoretical and experimental values can be precisely determined. Previous measurements were performed decades ago at LAMPF with uncertainties mostly dominated by statistical errors. At the J-PARC Muon Science Facility (MUSE), the MuSEUM collaboration is planning complementary measurements of muonium HFS both at zero and high magnetic field. The new high-intensity muon beam that will soon be available at H-Line will provide an opportunity to improve the precision of these measurements by one order of magnitude. An overview of the different aspects of these new muonium HFS measurements, the current status of the preparation for high-field measurements, and the latest results at zero field are presented.

Usefulness of TSH receptor antibodies as biomarkers for Graves' ophthalmopathy: a systematic review

PURPOSE

Over the past several decades, many papers have been published about the usefulness of thyrotropin receptor antibodies (TRAbs) as biomarkers of Graves' ophthalmopathy (GO). However, results have been inconsistent. The purpose of this analysis is to determine a possible cause of these discrepancies and to examine the usefulness of TRAbs as biomarkers for GO, especially 'thyrotropin-binding inhibiting immunoglobulin (TBII)' and 'thyroid-stimulating antibody (TSAb)'.

METHOD

26 articles discussing the association between TRAbs and GO were selected which were then divided into three groups based on the study method and whether or not the patients had been treated for hyperthyroidism. From the results of the papers reviewed, a provisional conclusion was made and a theoretical model on the TBII-TSAb coordinate plane was developed to confirm that conclusion.

RESULTS

TSAb is reported to be significantly or strongly associated with GO in the studies of pre- and post-treated patients for hyperthyroidism. TBII is positively correlated, negatively correlated or uncorrelated with GO in studies of pre-treated patients. However, it is generally agreed upon that TBII and GO are closely correlated in studies of post-treated patients.

CONCLUSION

We conclude that the level of TBII may not be a reliable indicator of the current state of GO in pre-treated patients. Whereas, in post-treated patients, due to changes in the correlation between TBII and TSAb due to the effect of hyperthyroidism treatment, the level of TBII can be a more reliable indicator of GO. Furthermore, the current level of TBII is closely associated with the onset and severity of GO in the future and it can be a valid predictor of GO. However, the TSAb level appears to be more reliable.