Prognostic Role of Preoperative Chemotherapy in Liver-Limited Metastasis from Gastric Cancer

BACKGROUND

We investigated the prognostic role of preoperative chemotherapy in patients who underwent hepatectomy for liver-limited metastasis (LLM) from gastric cancer (GC).

METHODS

A retrospective analysis was conducted for 52 consecutive patients who underwent macroscopically complete (R0 or R1) resection for synchronous or metachronous LLM from GC.

RESULTS

Of the 52 patients, 18 (35%) received preoperative chemotherapy (PC group), while 34 (65%) underwent upfront surgery (US group). The PC group had a significantly longer overall survival than the US group (cumulative 5-year OS rate: 47.6% vs. 24.8%, p = 0.041). Multivariate analysis of OS revealed that preoperative chemotherapy was an independent favorable prognostic factor (hazard ratio: 0.445, p = 0.036). Patients showing a partial response to preoperative chemotherapy on RECIST had an improved OS compared with those exhibiting stable or progressive disease after preoperative chemotherapy and with US (p = 0.025), even among those with solitary LLM (p = 0.062) and multiple LLM (p = 0.026). At recurrence after hepatectomy for LLM, the PC group had a significantly higher incidence of solitary tumors than the US group (p = 0.043) and had a higher chance to undergo surgical resection for recurrent sites (p = 0.006).

CONCLUSIONS

Preoperative chemotherapy can be recommended for patients with LLM from GC. The evaluation of the efficacy of preoperative chemotherapy offers additional information to determine the surgical indication for LLM.

Activin a Receptor Type 2A Mutation Affects the Tumor Biology of Microsatellite Instability-High Gastric Cancer

BACKGROUND

Activin A receptor type 2A (ACVR2A) is one of the most frequently mutated genes in microsatellite instability-high (MSI-H) gastric cancer. However, the clinical relevance of the ACVR2A mutation in MSI-H gastric cancer patients remains unclear. The aims of this study were to explore the effect of ACVR2A mutation on the tumor behavior and to identify the clinicopathological characteristics of gastric cancer patients with ACVR2A mutations.

METHODS

An in vitro study was performed to investigate the biological role of ACVR2A via CRISPR/Cas9-mediated ACVR2A knockout MKN74 human gastric cancer cells. One hundred twenty-four patients with gastric cancer were retrospectively analyzed, and relations between MSI status, ACVR2A mutations, and clinicopathological factors were evaluated.

RESULTS

ACVR2A knockout cells showed less aggressive tumor biology than mock-transfected cells, displaying reduced proliferation, migration, and invasion (P < 0.05). MSI mutations were found in 10% (13/124) of gastric cancer patients, and ACVR2A mutations were found in 8.1% (10/124) of patients. All ACVR2A mutations were accompanied by MSI. The 5-year overall survival rates of ACVR2A wild-type patients and ACVR2A-mutated patients were 57% and 90%, respectively (P = 0.048). Multivariate analysis revealed that older age (P = 0.015), distant metastasis (P < 0.001), and ACVR2A wild-type status (P = 0.040) were independent prognostic factors for overall survival.

CONCLUSIONS

Our study demonstrated that gastric cancer patients with ACVR2A mutation have a significantly better prognosis than those without. Dysfunction of ACVR2A in MKN74 human gastric cancer cells caused less aggressive tumor biology, indicating the importance of ACVR2A in the progression of MSI-H tumors.

Profiling of host genetic alterations and intra-tumor microbiomes in colorectal cancer

Some bacteria are symbiotic in tumor tissues, and metabolites of several bacterial species have been found to cause DNA damage. However, to date, the association between bacteria and host genetic alterations in colorectal cancer (CRC) has not been fully investigated. We evaluated the association between the intra-tumor microbiome and host genetic alterations in 29 Japanese CRC patients. The tumor and non-tumor tissues were extracted from the patients, and 16S rRNA genes were sequenced for each sample. We identified enriched bacteria in tumor and non-tumor tissues. Some bacteria, such as Fusobacterium, which is already known to be enriched in CRC, were found to be enriched in tumor tissues. Interestingly, Bacteroides, which is also known to be enriched in CRC, was enriched in non-tumor tissues. Furthermore, it was shown that certain bacteria that often coexist within tumor tissue were enriched in the presence of a mutated gene or signal pathway with mutated genes in the host cells. Fusobacterium was associated with many mutated genes, as well as cell cycle-related pathways including mutated genes. In addition, the patients with a high abundance of Campylobacter were suggested to be associated with mutational signature 3 indicating failure of double-strand DNA break repairs. These results suggest that CRC development may be partly caused by DNA damage caused by substances released by bacterial infection. Taken together, the identification of distinct gut microbiome patterns and their host specific genetic alterations might facilitate targeted interventions, such as modulation of the microbiome in addition to anticancer agents or immunotherapy.

NQO1 as a Marker of Chemosensitivity and Prognosis for Colorectal Liver Metastasis

BACKGROUND/AIM

This study aimed to evaluate how NAD(P)H: quinone oxidoreductase-1 (NQO1) affects survival after hepatectomy in patients with colorectal liver metastasis (CRLM).

PATIENTS AND METHODS

A retrospective analysis was conducted of 88 consecutive patients who underwent hepatectomy for CRLM. Of the 88 patients, preoperative chemotherapy was administered to 30 patients. Immunohistochemistry of the resected specimens was conducted using monoclonal anti-NQO1 antibody.

RESULTS

NQO1-positive expression in tumor cells of CRLM was associated with worse overall survival (p=0.026) and was an independent adverse prognostic factor in multivariate analysis (hazard ratio=5.296, p=0.007). Among 30 patients who received preoperative chemotherapy, patients with loss of NQO1 expression in non-neoplastic epithelial cells of the bile ducts (NQO1 polymorphism: n=19) showed significantly better response to preoperative chemotherapy for CRLM (p=0.004).

CONCLUSION

NQO1-positive expression in tumor cells of CRLM may be an adverse prognostic factor after hepatectomy for CRLM.

Outcome of radical surgery for gallbladder carcinoma according to TNM stage: implications for adjuvant therapeutic strategies

PURPOSE

Outcomes following surgery for advanced gallbladder carcinoma remain unsatisfactory. This study aimed to determine the surgical outcome and effectiveness of adjuvant chemotherapy according to TNM stage in patients with gallbladder carcinoma.

METHODS

A total of 200 patients undergoing surgery for gallbladder carcinoma were enrolled. Clinicopathological data were evaluated and surgical outcomes were compared between patients with and without adjuvant chemotherapy according to TNM stage.

RESULTS

The 5-year overall survival (OS) after resection for patients with stage I (n = 27), IIA (n = 18), IIB (n = 28), IIIA (n = 25), IIIB (n = 43), IVA (n = 7), and IVB (n = 52) disease was 90.8%, 94.4%, 73.6%, 33.7%, 57.7%, 14.3%, and 11.8%, respectively (p < 0.001). R0 resection was performed in all patients with stage I or II disease, in 89.7% of those with stage III disease, and 69.5% of those with stage IV disease. For patients with stage III disease, adjuvant chemotherapy was associated with improved OS (5-year OS, 60.9% vs. 41.1%; p = 0.028) and was an independent prognostic factor (hazard ratio, 2.045; p = 0.039). For patients with stage IV disease, adjuvant chemotherapy appeared to affect OS (5-year OS, 25.1% vs. 5.3%; p = 0.041); R0 resection (hazard ratio, 1.882; p = 0.040) was the only independent prognostic factor.

CONCLUSION

TNM stage clearly predicts survival after resection of gallbladder carcinoma. R0 resection with adjuvant chemotherapy is recommended for long-term survival in the multimodal management of patients with stage III or IV gallbladder carcinoma.

[Long-Term Survival after Surgery with Postoperative Chemotherapy for Perihilar Cholangiocarcinoma with Residual Invasive Carcinoma at Ductal Resection Margins-A Case Report]

A 64-year-old man with liver dysfunction was given a diagnosis of perihilar cholangiocarcinoma(Bismuth type Ⅳ). The tumor was predominantly right-sided and invaded to the bifurcation of the right and left portal veins. After confirming sufficient liver functional reserve and future liver remnant, the patient underwent extended right hepatectomy, extrahepatic bile duct resection, and portal vein resection and reconstruction. Intraoperative examination of frozen sections revealed the presence of residual invasive carcinoma on both the hepatic and duodenal sides of the ductal resection margins. However, we did not perform pancreaticoduodenectomy or additional resection of the margin-positive proximal bile duct considering the curability and invasiveness of these procedures. He received postoperative chemotherapy with biweekly gemcitabine plus cisplatin for 1 year, followed by gemcitabine monotherapy for 1 year, and S-1 monotherapy has been performed since then. He remains alive and well with no evidence of disease 63 months after surgery.

[A Case of Umbilical Metastasis from Pancreatic Cancer after Surgery]

The patient was a 63-year-old woman with diagnosis of pancreatic cancer. Abdominal CT showed pancreatic head tumor and paraaortic lymph node metastasis. We performed chemotherapy with nab-paclitaxel plus gemcitabine. After 5 courses of chemotherapy, the tumor reduced in size. Pancreaticoduodenectomy followed by adjuvant chemotherapy with S-1 was performed. Fourteen months after surgery, umbilical metastasis(Sister Mary Joseph's nodule: SMJN)was found in the umbilicus near the abdominal incisional hernia. There was no evidence of metastasis except in the umbilicus, we performed the umbilical tumor resection and abdominal incisional hernia repair. Pathological diagnosis was pancreatic cancer metastasis. Although following chemotherapy, multiple skin metastases was found in the lower abdomen 3 months after umbilical resection. We performed skin metastases resection to relieve pain and symptoms of bleeding. But she died 29 months after the initial therapy(7 months after umbilical resection).

Inguinal Herniation After Living Donor Kidney Transplantation: A Case Report

A 68-year-old male patient received a living donor kidney transplantation 8 years earlier for end-stage kidney disease secondary to IgA nephropathy. His post-transplantation follow-up had been routinely performed with laboratory examinations, ultrasound, and computed tomography (CT). His kidney graft function had been excellent and stable, as shown by a baseline serum creatinine level of 1.0 mg/dL. At referral, regular follow-up ultrasound and CT showed allograft hydroureteronephrosis. He did not have any complaints, but his physical examination revealed right inguinal bulging that was 3.5 × 3.5 cm. Abdominal enhanced CT revealed transplant allograft hydroureteronephrosis due to ipsilateral herniation of ureteroneocystostomy into the right inguinal canal. His serum creatinine level was slightly elevated (1.1 mg/dL). Then, he underwent an open right inguinal hernia repair. Paraperitoneal allograft hydroureteronephrosis and bladder herniation was confirmed at surgery, and hernioplasty with polypropylene mesh reinforcement was successfully performed. The postoperative course was uneventful. He was discharged on the seventh day after surgery. Six weeks after surgery, CT revealed disappearance of allograft hydroureteronephrosis and no sign of inguinal hernia recurrence with the serum creatinine stable at 1.0 mg/dL. Transplant ureteral obstruction due to inguinal hernia is a rare complication after kidney transplantation. However, transplant ureter or bladder herniation should be considered in the differential diagnosis of graft hydroureteronephrosis for preventing allograft loss.

Long-term outcomes of surgical resection for T1b gallbladder cancer: an institutional evaluation

BACKGROUND

There is no comprehensive agreement concerning the overall performance of radical resection for T1b gallbladder cancer (GBC). This research focused on addressing whether T1b GBC may spread loco-regionally and whether radical resection is necessary.

METHODS

A retrospective analysis was conducted of 1032 patients with GBC who underwent surgical resection at our centre and its affiliated institutions between January 1982 and December 2018. A total of 47 patients with T1b GBC, 29 (62%) of whom underwent simple cholecystectomy and 18 (38%) of whom underwent radical resection with regional lymph node dissection, were enrolled in the study.

RESULTS

GBC was diagnosed pre-operatively in 16 patients (34%), whereas 31 patients (66%) had incidental GBC. There was no blood venous or perineural invasion in any patient on histology evaluation, except for lymphatic vessel invasion in a single patient. There were no metastases in any analysed lymph nodes. The open surgical approach was more prevalent among the 18 patients who underwent radical resection (open in all 18 patients) than among the 29 patients who underwent simple cholecystectomy (open in 21; laparoscopic in 8) (P = 0.017). The cumulative 10- and 20-year overall survival rates were 65 and 25%, respectively. The outcome following simple cholecystectomy (10-year overall survival rate of 66%) was akin to that following radical resection (64%, P = 0.618). The cumulative 10- and 20-year disease-specific survival rates were 93 and 93%, respectively. The outcome following simple cholecystectomy (10-year disease-specific survival rate of 100%) was equivalent to that following radical resection (that of 86%, P = 0.151). While age (> 70 years, hazard ratio 5.285, P = 0.003) and gender (female, hazard ratio 0.272, P = 0.007) had a strong effect on patient overall survival, surgical procedure (simple cholecystectomy vs. radical resection) and surgical approach (open vs. laparoscopic) did not.

CONCLUSIONS

Most T1b GBCs represent local disease. As pre-operative diagnosis, including tumour penetration of T1b GBC, is difficult, the decision of radical resection is justified. Additional radical resection is not required following simple cholecystectomy provided that the penetration depth is restricted towards the muscular layer and that surgical margins are uninvolved.

[A Case of Peritoneal Metastases after Radiofrequency Ablation for Liver Metastasis from a Pancreatic Neuroendocrine Tumor]

A 77-year-old woman presented with peritoneal metastases from a pancreatic neuroendocrine tumor(p-NET). At the age of 56 years, she underwent distal pancreatectomy for p-NET, which was pathologically diagnosed as G2. She underwent right hemihepatectomy for liver metastasis(S6)from the p-NET 10 years post-pancreatectomy. Eight years post-hepatectomy, radiofrequency ablation(RFA)was attempted for liver metastasis(S4)from the p-NET. However, RFA was not completed because of hematoma development along the needle tract of RFA. She underwent partial hepatectomy for this lesion 6 months post-RFA. Two years post-RFA, localized peritoneal metastases on the right diaphragm were detected. She underwent en bloc tumor resection with partial resection of the diaphragm. She remains alive and well with no evidence of disease 2 years post-resection of the peritoneal metastases from the p-NET.

Early-stage T1b adenocarcinoma arising in the remnant cystic duct after laparoscopic cholecystectomy: a case report and literature review

Background

The cystic duct has been included in the staging classification scheme for gallbladder cancer since the 2010 publication of the AJCC Cancer Staging Manual (7th edition). To our knowledge, only seven other cases of adenocarcinoma arising in the remnant cystic duct following cholecystectomy have been reported in the English-language literature, and none has been reported as primary early-stage T1b remnant cystic duct cancer (CDC). We report, herein, a case of primary adenocarcinoma arising in the remnant cystic duct in a patient with history of laparoscopic cholecystectomy for gallstone disease.

Case presentation

An 81-year-old female presented with abdominal pain. Her medical history included a laparoscopic cholecystectomy for cholecystolithiasis two years prior. Jaundice was observed; imaging studies suggested that this was caused by choledocholithiasis. Blood chemistry findings showed severe liver dysfunction. Endoscopic retrograde cholangiography revealed haemobilia from the common bile duct with no evidence of choledocholithiasis. A bile sample showed Papanicolaou class IV cytology. As the extent of tumour spread was undetermined by abdominal ultrasonography and endoscopic ultrasonography, peroral cholangioscopy (POCS) was performed, which revealed tiny papillary lesions within the confluence of cystic duct, and fine granular lesions in the centre of bile ducts, signifying early-stage remnant CDC. Extrahepatic bile duct resection with regional lymphadenectomy was done. Histopathological findings revealed a 42-mm tubular adenocarcinoma originating from the remnant cystic duct with the considerable shallow spread across the extrahepatic bile ducts. It invaded the fibromuscular layer, with no lymphovascular or perineural invasion, no lymph node metastasis (13 nodes examined), and uninvolved surgical resection margin (R0 resection), and was staged as pT1bN0M0, Stage I.

Conclusions

Primary early-stage T1b remnant CDC is an uncommon condition for which early diagnosis is challenging; if intraoperatively recognized, it can complicate surgery. Our experience of this case and an overview of the English literature suggest that POCS is an efficient tool to diagnosis this tumour and assess its spread along the extrahepatic bile ducts.

Lymphatic spread of T2 gallbladder carcinoma: Regional lymphadenectomy is required independent of tumor location

BACKGROUND

This study aimed to investigate the incidence and distribution of regional lymph node metastasis according to tumor location, and to clarify whether tumor location could determine the extent of regional lymphadenectomy in patients with pathological T2 (pT2) gallbladder carcinoma.

METHODS

In total, 81 patients with pT2 gallbladder carcinoma (25 with pT2a tumors and 56 with pT2b tumors) who underwent radical resection were enrolled. Tumor location was determined histologically in each gallbladder specimen.

RESULTS

Survival after resection was significantly worse in patients with pT2b tumors than those with pT2a tumors (5-year survival, 72% vs. 96%; p = 0.027). Tumor location was an independent prognostic factor on multivariate analysis (hazard ratio, 14.162; p = 0.018). The incidence of regional lymph node metastasis was significantly higher in patients with pT2b tumors than in those with pT2a tumors (46% vs. 20%; p = 0.028). However, the number of positive nodes was similar between the two groups (median, 2 vs. 2; p = 0.910). For node-positive patients with pT2b tumors, metastasis was found in every regional node group (12%-63%), whereas even for node-positive patients with pT2a tumors, metastasis was observed in regional node groups outside the hepatoduodenal ligament.

CONCLUSIONS

Tumor location in patients with pT2 gallbladder carcinoma can predict the presence or absence of regional lymph node metastasis but not the number and anatomical distribution of positive regional lymph nodes. The extent of regional lymphadenectomy should not be changed even in patients with pT2a tumors, provided that they are fit enough for surgery.

[Surgical Resection after Transarterial Chemoembolization for Hepatocellular Carcinoma with Bile Duct Tumor Thrombus-Report of a Long-Term Survivor]

A 78-year-old woman with jaundice was referred to our hospital. On admission, serological testing for viral hepatitis was negative and serum levels of AFP and PIVKA-Ⅱ were elevated(925 ng/mL and 6,820 mAU/mL, respectively). Computed tomography revealed a main tumor measuring 3 cm in size at segment 1 of the liver and bile duct tumor thrombus extending to the right hepatic duct. A diagnosis of hepatocellular carcinoma with a bile duct tumor thrombus was made. After endoscopic biliary drainage for obstructive jaundice and transarterial chemoembolization for the lesions, she underwent left hepatectomy, resection of the caudate lobe, extrahepatic bile duct resection, and cholecystectomy. The hepatic side of the extrahepatic bile duct was transected at the confluence of the right anterior and posterior ducts because invasion of the tumor thrombus to the right hepatic duct was suspected on cholangioscopy. Histological examination revealed the tumor to be a moderately differentiated hepatocellular carcinoma with bile duct tumor thrombus. Surgical margins were negative, and vascular invasion was not found. She remains alive and well with no evidence of disease 64 months after hepatectomy.

[A Case of Peritoneal Recurrence of Invasive Ductal Carcinoma Derived from Intraductal Papillary Mucinous Neoplasm after Surgery Treated with Palliative Radiation Therapy and Chemotherapy]

An 82-year-old man with a diagnosis ofintraductal papillary mucinous carcinoma(IPMC)underwent pancreaticoduodenectomy followed by adjuvant chemotherapy with S-1. Six months after surgery, he had upper abdominal pain, and CT demonstrated a recurrent intraabdominal tumor located at the surgical incision scar. It was diagnosed as a solitary peritoneal recurrence, and palliative radiation therapy at a dose of 30 Gy was performed for the relief of abdominal pain after administration ofoxycodone. He was free ofpain without pharmacological therapy and received subsequent chemotherapy with nabpaclitaxel plus gemcitabine(GnP). He remains free ofpain and alive without progression ofthe disease 24 months after recurrence. Hypofractionated-accelerated radiotherapy is feasible and results in pain relief for local recurrence of IPMC.

[Pancreaticoduodenectomy for Recurrent Retroperitoneal Liposarcoma]

A 56-year-old woman was referred to our hospital with complaints of appetite loss and abdominal distension. Enhanced abdominal computed tomography revealed a giant retroperitoneal tumor. We performed en bloc tumor resection. The histological diagnosis was of a dedifferentiated liposarcoma. One year after the initial surgery, 2 tumors were detected around the pancreas using computed tomography. We made a diagnosis of recurrent retroperitoneal liposarcoma and attempted surgical removal of the tumors. However, 1 of the tumors firmly adhered to the pancreas and duodenum; thus, we performed subtotal stomach-preserving pancreaticoduodenectomy to remove the tumors. The histological diagnosis was the same as that obtained during the initial surgery: a dedifferentiated liposarcoma. The patient remains alive and well with no evidence of disease 2 years after the initial surgery.

[A Case of Long-Term Survival after Reoperation for Neck Lymph Node Metastasis Occurring Seven Years after Pancreaticoduodenectomy for Pancreatic Adenocarcinoma]

A 59-year-old woman with pancreatic cancer underwent pancreaticoduodenectomy. The tumor was histologically diagnosed as a well-differentiated tubular adenocarcinoma with a small amount of mucinous component. After resection, the patient underwent hepatic perfusion therapy using 5-FU and gemcitabine chemotherapy for 1 year. 7 years after the initial surgery, CT and PET-CT revealed an isolated enlarged lymph node in the left neck. As the patient had no other metastasis, lymphadenectomy was performed. A diagnosis of lymph node metastasis originating from pancreatic cancer was confirmed on the basis of histological and immunohistopathological assessments. After the second resection, chemotherapy with S-1 was administered for 1 year. The patient has been alive without tumor relapse for 11 years. In patients with late recurrence after pancreatectomy, aggressive isolated lymph node resection and maintained chemotherapy may contribute to the improvement in prognosis.

[Surgical Resection for Peritoneal Metastasis in Hepatocellular Carcinoma-A Report of Three Cases]

Peritoneal metastasis is relatively rare in patients with hepatocellular carcinoma(HCC). No consensus has been reached regarding the treatment of this type of metastasis. Herein, we report 3 patients who underwent resection of peritoneal metastasis due to HCC. Case 1: A 48-year-old man underwent hepatectomy twice and radiofrequency ablation(RFA)once for HCC. Eight years after the initial resection, he underwent resection of peritoneal metastasis in the pelvic floor. He is alive with disease 17 months after the last operation. Case 2: A 71-year-old man with a history of percutaneous ablation therapy for HCC 3 times underwent hepatectomy for recurrent HCC. During the laparotomy, a peritoneal metastatic tumor was found near the live tumor, and simultaneous resection of both the tumors was performed. The patient died of recurrent disease 20 months after the last resection. Case 3: A 58-year-old man underwent hepatectomy for HCC and RFA for its recurrence. Peritoneal metastasis that invaded the duodenum was detected 8 years after the hepatectomy. Although the metastatic tumor was resected, he died of the carcinoma 2 months after the resection. We concluded that resection of peritoneal metastasis provides a survival benefit for selected patients with HCC.

Common driver mutations and smoking history affect tumor mutation burden in lung adenocarcinoma

BACKGROUND

Recent progress in genomic analysis using next-generation sequencing technology has enabled the comprehensive detection of mutations and tumor mutation burden (TMB) in patients. A high TMB (TMB-H) tumor is defined as one with high somatic mutational rates, which correlates with clinical responses to certain treatments such as immunotherapies. We determined TMB in lung adenocarcinoma and clarified the characteristics of patients with TMB-H in relation to common driver mutations and smoking history.

MATERIALS AND METHODS

Genomic aberrations and TMB were determined in Japanese patients with lung adenocarcinoma (n = 100) using next-generation sequencing of 415 known cancer genes. TMB-H was defined as > 20 mutations per megabase (Mb) of sequenced DNA.

RESULTS

The median TMB was 13.5 (5-33) mutations/Mb. Ten of 100 (10%) patients showed TMB-H, and the others showed low TMB (TMB-L). Only two of 10 (20%) patients with TMB-H had one of the common driver mutations (ALK and ERBB2 mutation), whereas 57 of 90 (63%) patients with TMB-L had one of the driver mutations, including ALK, EGFR, ERBB2, ROS, RET, and MET (P < 0.05). Notably, no EGFR mutation was observed in patients with TMB-H. Eight of 10 (80%) patients with TMB-H had recent smoking history, whereas only 17 of 90 (19%) patients with TMB-L had recent smoking history (P < 0.001).

CONCLUSIONS

We found that TMB-H is associated with smoking history, whereas TMB-L is associated with the common driver mutations in lung adenocarcinoma, which may impact treatment strategies for these patients.

Generation of sphingosine-1-phosphate is enhanced in biliary tract cancer patients and is associated with lymphatic metastasis

Lymphatic metastasis is known to contribute to worse prognosis of biliary tract cancer (BTC). Recently, sphingosine-1-phosphate (S1P), a bioactive lipid mediator generated by sphingosine kinase 1 (SPHK1), has been shown to play an important role in lymphangiogenesis and lymph node metastasis in several types of cancer. However, the role of the lipid mediator in BTC has never been examined. Here we found that S1P is elevated in BTC with the activation of ceramide-synthetic pathways, suggesting that BTC utilizes SPHK1 to promote lymphatic metastasis. We found that S1P, sphingosine and ceramide precursors such as monohexosyl-ceramide and sphingomyelin, but not ceramide, were significantly increased in BTC compared to normal biliary tract tissue using LC-ESI-MS/MS. Utilizing The Cancer Genome Atlas cohort, we demonstrated that S1P in BTC is generated via de novo pathway and exported via ABCC1. Further, we found that SPHK1 expression positively correlated with factors related to lymphatic metastasis in BTC. Finally, immunohistochemical examination revealed that gallbladder cancer with lymph node metastasis had significantly higher expression of phospho-SPHK1 than that without. Taken together, our data suggest that S1P generated in BTC contributes to lymphatic metastasis.

Upregulation of phosphorylated sphingosine kinase 1 expression in colitis-associated cancer

BACKGROUND

Colitis-associated cancer (CAC) is the most serious complication of inflammatory bowel disease. Sphingosine-1-phosphate (S1P) is a bioactive lipid mediator that is generated by sphingosine kinase 1 (SphK1) and is known to play an important role in inflammation and cancer progression. Moreover, SphK1 and S1P act as upstream mediators of proinflammatory cytokine interleukin 6 (IL-6) and signal transducer and activator of transcription-3 (STAT3). We hypothesized that the expression levels of phosphorylated SphK1 (pSphK1), phosphorylated STAT3 (pSTAT3), and IL-6 are universally higher in CAC patients than in sporadic colorectal cancer (CRC) patients because all of these factors are associated with inflammation. In this study, we determined the expression levels of pSphK1 in patients with sporadic CRC and CAC and clarified the importance of S1P in CAC patients.

MATERIALS AND METHODS

We randomly selected 10 sporadic CRC patients and 10 CAC patients who underwent curative resection, and we examined their surgical specimens by immunohistochemistry. We determined the expression levels of pSphK1, pSTAT3, and IL-6 in these samples.

RESULTS

We found pSphK1 expression to be more prevalent in CAC patients (P = 0.019) and to have a higher immunohistochemistry score (P = 0.005) than in sporadic CRC patients. However, the expression of pSTAT3 and IL-6 did not differ between the patient groups.

CONCLUSIONS

To our knowledge, this is the first report comparing pSphK1 expression levels in CAC with those in sporadic CRC. The high levels of pSphK1 expression in CAC suggest an important role of S1P in the disease process of CAC.

Targeting the SphK1/S1P/S1PR1 Axis That Links Obesity, Chronic Inflammation, and Breast Cancer Metastasis

Although obesity with associated inflammation is now recognized as a risk factor for breast cancer and distant metastases, the functional basis for these connections remain poorly understood. Here, we show that in breast cancer patients and in animal breast cancer models, obesity is a sufficient cause for increased expression of the bioactive sphingolipid mediator sphingosine-1-phosphate (S1P), which mediates cancer pathogenesis. A high-fat diet was sufficient to upregulate expression of sphingosine kinase 1 (SphK1), the enzyme that produces S1P, along with its receptor S1PR1 in syngeneic and spontaneous breast tumors. Targeting the SphK1/S1P/S1PR1 axis with FTY720/fingolimod attenuated key proinflammatory cytokines, macrophage infiltration, and tumor progression induced by obesity. S1P produced in the lung premetastatic niche by tumor-induced SphK1 increased macrophage recruitment into the lung and induced IL6 and signaling pathways important for lung metastatic colonization. Conversely, FTY720 suppressed IL6, macrophage infiltration, and S1P-mediated signaling pathways in the lung induced by a high-fat diet, and it dramatically reduced formation of metastatic foci. In tumor-bearing mice, FTY720 similarly reduced obesity-related inflammation, S1P signaling, and pulmonary metastasis, thereby prolonging survival. Taken together, our results establish a critical role for circulating S1P produced by tumors and the SphK1/S1P/S1PR1 axis in obesity-related inflammation, formation of lung metastatic niches, and breast cancer metastasis, with potential implications for prevention and treatment.Significance: These findings offer a preclinical proof of concept that signaling by a sphingolipid may be an effective target to prevent obesity-related breast cancer metastasis. Cancer Res; 78(7); 1713-25. ©2018 AACR.

Hypermutation and microsatellite instability in gastrointestinal cancers

Recent progress in cancer genome analysis using next-generation sequencing has revealed a high mutation burden in some tumors. The particularly high rate of somatic mutation in these tumors correlates with the generation of neo-antigens capable of eliciting an immune response. Identification of hypermutated tumors is therefore clinically valuable for selecting patients suitable for immunotherapy treatment. There are several known causes of hypermutation in tumors, such as ultraviolet light in melanoma, tobacco smoke in lung cancer, and excessive APOBEC (apolipoprotein B mRNA editing enzyme, catalytic polypeptide-like) activity in breast and gastric cancer. In gastrointestinal cancers, one of the leading causes of hypermutation is a defect in DNA mismatch repair, which results in microsatellite instability (MSI). This review will focus on the frequency, characteristics and genomic signature of hypermutated gastrointestinal cancers with MSI. Detection of tumor hypermutation in cancer is expected to not only predict the clinical benefit of immune checkpoint inhibitor treatment, but also to provide better surgical strategies for the patients with hypermutated tumors. Thus, in an era of precision medicine, identification of hypermutation and MSI will play an important role directing surgical and chemotherapeutic treatment.

[Mixed Type Liposarcoma with Intra-Abdominal Bleeding - Report of a Case]

A 71-year-old man presented with sudden abdominal pain. He had past history of atrial fibrillation, cerebral infarction and heart-valve replacement and received anticoagulant therapy with warfarin. Computed tomography of the abdomen revealed bloody ascites and a huge mass in contact with the third portion of the duodenum. The mass was encapsulated and consisted of a solid component with calcification and hematoma. Under the preoperative diagnosis of gastrointestinal stromal tumor with intra-abdominal bleeding, laparotomy was performed. Intraoperative findings revealed the tumor arising from the right mesocolon and excision of the tumor with right hemicolectomy was performed. Histologic examination confirmed a diagnosis of mixed type liposarcoma. No postoperative complication was observed and he was discharged home on the 8th postoperative day. He remains alive and well with no evidence of disease 52 months after resection.

[A Case of Hepatocellular Carcinoma with Lymph Node Metastasis Successfully Treated by Multidisciplinary Treatment]

Lymph node metastasis has a poor prognosis in patients with hepatocellular carcinoma(HCC). We report a case of HCC with lymph node metastasis successfully treated by multidisciplinary treatment. An 81-year-old woman who was followed up for liver cirrhosis received a diagnosis of HCC, which was detected by CT as a solitary tumor 20mm in diameter in the couinaud segment 7 of the liver. She underwent transcatheter arterial chemoembolization(TACE)twice for HCC because of her advanced age and no intention to undergo hepatectomy. Some 12 months later, local recurrence was managed by repeat TACE and paraaortic lymph node metastasis by surgical resection. The patient received radiotherapy for mediastinal nodal disease 6 months after the resection. She remains alive and well without no evidence of disease 84 months after the initial treatment. This case and a review of the literature suggest that multidisciplinary treatment with TACE, surgical resection and radiotherapy may provide a survival benefit for selected patients with HCC with isolated lymph node metastasis.

Hand-assisted laparoscopic Hassab's procedure for esophagogastric varices with portal hypertension

Background

Laparoscopic surgery for patients with portal hypertension is considered to be contraindicated because of the high risk of massive intraoperative hemorrhaging. However, recent reports have shown hand-assisted laparoscopic surgery for devascularization and splenectomy to be a safe and effective method of treating esophagogastric varices with portal hypertension. The aim of this study is to evaluate the efficacy of hand-assisted laparoscopic devascularization and splenectomy (HALS Hassab’s procedure) for the treatment of esophagogastric varices with portal hypertension.

Case presentation

From 2009 to 2016, seven patients with esophagogastric varices with portal hypertension were treated with hand-assisted laparoscopic devascularization and splenectomy in our institute. Four men and three women with a median age of 61 years (range 35–71) were enrolled in this series. We retrospectively reviewed the medical records for the perioperative variables, postoperative mortality and morbidity, and postoperative outcomes of esophagogastric varices. The median operative time was 455 (range 310–671) min. The median intraoperative blood loss was 695 (range 15–2395) ml. The median weight of removed spleen was 507 (range 242–1835) g. The conversion rate to open surgery was 0%. The median postoperative hospital stay was 21 (range 13–81) days. During a median 21 (range 3–43) months of follow-up, the mortality rate was 0%. Four postoperative complications (massive ascites, enteritis, intra-abdominal abscess, and intestinal ulcer) were observed in two patients. Those complications were treated successfully without re-operation. Esophagogastric varices in all patients disappeared or improved. Bleeding from esophagogastric varices was not observed during the follow-up period.

Conclusion

Although our data are preliminary, hand-assisted laparoscopic devascularization and splenectomy proved an effective procedure for treating esophagogastric varices in patients with portal hypertension.

Genomic overview of right-sided and left-sided colorectal cancer using comprehensive genomic sequencing

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Background: Although the difference in right vs. left sidedness of colorectal cancer (CRC) in response to targeted therapy has been reported, we hypothesized that right-sided colorectal cancer (RCC) is more likely to have genetic alterations associated with resistance of anti-EGFR therapy. We tested this hypothesis using comprehensive genomic sequencing (CGS) on a set of samples from well-characterized CRC patients. Methods: Two-hundred-one primary colon cancer patients with either RCC or left-sided colorectal cancer (LCC) were analyzed. We investigated gene alterations using 415 gene panel, which includes the gene alterations associated with resistance of anti-EGFR therapy: TK receptors ( ERBB2, MET, EGFR, FGFR1, and PDGFRA), RAS pathway ( KRAS, NRAS, HRAS, BRAF, and MAPK2K1), and PI3K pathway ( PTEN and PIK3CA). We defined the patients who had no alterations in any of the genes as “all wild-type”, who are theoretically considered as responders of anti-EGFR therapy. Other patients with genetic alterations in resistance pathways were defined as “mutant-type”. Results: Fifty-six patients (28%) and 145 patients (72%) had RCC and LCC, respectively. Mutation of PIK3CA, BRAF, ACVR2A, MSH6, and CTNNB1 were significantly associated with RCC. Conversely, mutation of APC and TP53 were significantly associated with LCC. Regarding the gene alterations associated with anti-EGFR therapy, only 6 of 56 patients (11%) of RCC were “all wild-type”; in contrast to 41 of 145 patients (28%) of LCC that were “all wild-type” ( P = 0.009). In 45 Stage IV patients treated with anti-EGFR therapy, RCC showed significantly worse progression-free survival (PFS) than LCC ( P = 0.019), and “mutant-type” RCC showed worse PFS compared to the others ( P = 0.018). Conclusions: RCC is more likely to have the genetic alterations associated with resistance of anti-EGFR therapy compared to LCC. Primary tumor sidedness is a surrogate for the non-random distribution of molecular subtypes in CRC.

Association of activin type II receptor mutation with microsatellite instability in gastric cancer

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Background: Microsatellite instability-high status (MSI-H) and alterations in the DNA mismatch repair pathway associate with the efficacy of 5-FU and immune checkpoint inhibitors in patients with gastrointestinal cancers. The activin type II receptor (ACVR2) that binds to the transforming growth factor beta superfamily of ligands is frequently mutated in MSI-H colorectal cancer. However, the incidence of ACVR2 mutations in gastric cancer patients remains unclear. The aim of this study is to reveal the incidence and to examine the association between the MSI-H and ACVR2A mutations in gastric cancer patients. Methods: 124 archived FFPE gastric cancer tissues (stage I-IV), who were operated at Niigata University Medical and Dental Hospital or Niigata Cancer Center Hospital, were analyzed for ACVR2A mutation and MSI status with the NGS-based comprehensive genomic test platform. Clinicopathological characteristics of the patients were also examined. Results: All 124 gastric cancer patients were successfully analyzed. 13 out of 124 patients (10.4%) showed MSI-H status. Interestingly, 10 of 13 MSI-H patients (76.9%) showed ACVR2A mutation, where none (0%) was found among patients with microsatellite stable status (P < 0.001), indicating the strong association between ACVR2A mutation and MSI status in gastric cancer patients. In the ACVR2A mutated group, there was a female predominance (P < 0.05), and cancers of the lower part of the stomach were more common (P < 0.05), compared with the wild type group. Only one of 10 patients with ACVR2A mutation died, and the patients with ACVR2A mutation show a 5-year overall survival rate of 90%. No statistically significant difference in survival was achieved between patients with ACVR2A mutation and wild type; this is probably due to the small number of patients. Conclusions: 10 of 13 MSI-H patients showed ACVR2A mutation. Our results indicate a strong association between ACVR2A mutation and MSI-H in gastric cancer patients.

Comprehensive genomic sequencing for triple negative breast cancer in Japan

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Background: Breast cancer is the leading cancer among women both in US and Japan. Triple negative breast cancer (TNBC) is the subset of breast cancers that are negative for estrogen receptor (ER), progesterone receptor, and HER2. While the selective ER modulator tamoxifen or anti-HER2 therapy for breast cancer patients with ER positive or HER2 protein overexpression are the most successful examples of targeted therapies, only limited therapies are available for patients with TNBCs, which are associated with a poor prognosis. Advance in next-generation sequencing enables us to identify actionable driver mutations that can be potentially treated by targeted therapies in each cancer patient. The aim of this study is to examine actionable driver mutations in TNBCs in Japan by comprehensive genomic sequencing (CGS) with 435 gene panel, and compare the driver events in Japan with TCGA database to validate the utility of CGS. Methods: We examined all exons of 435 known cancer genes in Japanese TNBC patients (N = 53) by CGS and evaluated for concordance among independent data obtained from The Cancer Genome Atlas-TNBC whole exome sequencing database (N = 123). Results: Oncogenic driver mutations were identified in 51 of 53 Japanese patients (96%) with TNBC and 36 of 53 patients (67%) harbored mutations in genes associated with FDA-approved targeted therapies, indicating the potential clinical utility of a large gene panel for evaluating patients with TNBC. Among 80 total genetic alterations, frequently mutated genes ( > 10% patients) were TP53, PIK3CA and PTEN. Overall, the mutation spectrum of the Japanese patients is similar to that of the TCGA population, except amplification of MYC. Conclusions: Use of a CGS panel of 435 genes can reliably identify all of the critical mutations in TNBC patients, which are similar as TCGA data. The information derived from CGS can be used to determine the optimal treatment for TNBC patients.

Genomic profiling using a 435-gene panel provides a vision for precision medicine in Japanese gastric cancer

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Background: Molecular heterogeneity represents a significant hurdle in realizing precision medicine for gastric cancer (GC). Large-scale whole exome sequencing projects have identified distinct molecular subtypes to help define the heterogeneity of GC. However, it remains unclear whether the targeted gene panel-based sequencing can provide optimum targeted therapies and clinical utility in GC. The aim of this study is to generate comprehensive genomic profiling data and classify Japanese GC into actionable clusters associated with targeted therapies. Methods: FFPE tumor tissues were obtained from surgical or biopsy specimens of 207 Japanese patients with GC. Extracted DNA was subjected to genomic sequencing for 435 cancer related genes including 69 druggable genes with FDA approved targeted therapies. Somatic mutations, copy number alterations (SCNA), microsatellite instability (MSI) and Epstein-Barr virus (EBV) infection were evaluated using sequencing data. Results: Genomic sequencing identified at least one alteration of 435 genes in 194 pts (94%), and that of 69 druggable genes in 141 pts (68%). The most frequently altered druggable gene was ERBB2 (14%), following BRCA2 (11%) and ATM (10%). We successfully classified 207 tumors into four molecular subtypes, similar to the previously report; EBV (4%), MSI (8%), chromosomal instability (58%) and genomically stable subtype (30%). Frequent alterations of druggable genes ( > 5%) were widely observed through these subtypes. To discover the novel classifications associated with targeted therapies, we classified 207 tumors using mutation rate and hierarchical clustering. We identified a hypermutated group (n = 32), and a remaining non-hypermutated group (n = 175) which were sub-divided into six clusters including five actionable ones; ERBB2 (n = 25), CDKN2A and CDKN2B (n = 10), KRAS (n = 10), BRCA2 (n = 9) and ATM cluster (n = 12). Interestingly, we experienced a case of unresectable GC with a remarkable response for anti-HER2 therapy in the ERBB2 cluster. Conclusions: Genomic sequencing using a 435-gene panel has the potential to provide the information of optimum targeted therapies for upcoming precision medicine in Japanese GC.

[Long-Term Survival after Reoperation for Lung Metastasis of Resected Pancreatic Adenocarcinoma - A Case Report]

A 66-year-old woman with pancreatic cancer underwent resection of the pancreatic body and tail. Thirty-seven months after the initial surgery, a tumor was found in S4 of the right lung, for which resection of the middle lobe of the lung was performed. A diagnosis of lung metastasis originating from pancreatic cancer was confirmed based on histological and immunohistopathological assessments. Sixty-seven months after the initial surgery, despite the gemcitabine-based adjuvant chemotherapy, a tumor was detected in S3 of the left lung, for which partial lung resection was performed. Similar to the previous diagnosis, the tumor was diagnosed as lung metastasis of pancreatic cancer on the basis of the pathological findings. After the third operation, despite gemcitabine and S-1 chemotherapy, widespread pulmonary metastasis developed. One hundred and thirty months after the initial surgery, the patient died of respiratory failure due to carcinomatous pleurisy.

[Surgical Resection for Carcinoma Arising from the Remnant Intrapancreatic Bile Duct after Excision of a Congenital Choledochal Cyst - A Case Report]

A 77-year-old woman presented with a high fever. She had a history of resection of the extrahepatic bile duct, cholecystectomy, and hepaticojejunostomy for a congenital choledochal cyst, 23 years previously. Computed tomography showed a tumor measuring 90mm behind the head of the pancreas. This tumor appeared to invade the duodenum and pancreas, although swollen lymph nodes and distant metastasis were not detected. The patient was diagnosed with a carcinoma arising from the intrapancreatic remnant bile duct. A subtotal stomach-preserving pancreaticoduodenectomy and regional lymphadenectomy were performed. The patient remains alive and well with no evidence of disease 11 months after resection.

[Lymph Node Recurrence of Small Cell Carcinoma of the Extrahepatic Bile Ducts Effectively Treated with Cisplatin plus Irinotecan Chemotherapy - Report of a Case]

A 78-year-old man with jaundice was diagnosed with perihilar cholangiocarcinoma(Bismuth type I ). After endoscopic biliary drainage for jaundice, a subtotal stomach-preserving pancreaticoduodenectomy was performed. Histologic examination and immunohistochemical staining with chromogranin A, synaptophysin, and CD56 resulted in a diagnosis of small cell carcinoma. Of the 18 dissected lymph nodes, 8 nodes contained a metastatic tumor. Left supraclavicular and paraaortic lymph node metastases were detected by computed tomography 5 months after the resection. He received cisplatin plus irinotecan chemotherapy, and after 2 courses of the chemotherapy, both metastatic lesions were reduced in size. He remains alive and well with no evidence of progressive disease after 6 courses of chemotherapy.

The roles of bile acids and sphingosine-1-phosphate signaling in the hepatobiliary diseases

Based on research carried out over the last decade, it has become increasingly evident that bile acids act not only as detergents, but also as important signaling molecules that exert various biological effects via activation of specific nuclear receptors and cell signaling pathways. Bile acids also regulate the expression of numerous genes encoding enzymes and proteins involved in the synthesis and metabolism of bile acids, glucose, fatty acids, and lipoproteins, as well as energy metabolism. Receptors activated by bile acids include, farnesoid X receptor α, pregnane X receptor, vitamin D receptor, and G protein-coupled receptors, TGR5, muscarinic receptor 2, and sphingosine-1-phosphate receptor (S1PR)2. The ligand of S1PR2, sphingosine-1-phosphate (S1P), is a bioactive lipid mediator that regulates various physiological and pathophysiological cellular processes. We have recently reported that conjugated bile acids, via S1PR2, activate and upregulate nuclear sphingosine kinase 2, increase nuclear S1P, and induce genes encoding enzymes and transporters involved in lipid and sterol metabolism in the liver. Here, we discuss the role of bile acids and S1P signaling in the regulation of hepatic lipid metabolism and in hepatobiliary diseases.

Successful Endoscopic Management of Acute Necrotic Pancreatitis and Walled Off Necrosis After Auxiliary Partial Orthotopic Living-Donor Liver Transplantation: A Case Report

Endoscopic management of acute necrotic pancreatitis and walled off necrosis is less invasive than surgical treatment and has become the 1st choice for treating pancreatic necrosis and abscess. We treated a case of acute necrotic pancreatitis and walled off necrosis after auxiliary partial orthotopic living-donor liver transplantation (APOLT). A 24-year-old woman was admitted to our university hospital for removal of the internal biliary stent, which had already been placed endoscopically for the treatment of biliary stricture after APOLT. She had been treated for acute liver failure by APOLT 10 years before. After we removed the internal stent with the use of an endoscopic retrograde approach, she presented with severe abdominal pain and a high fever. Her diagnosis was severe acute pancreatitis after endoscopic retrograde cholangiography (ERC). Her symptoms worsened, and she had multiple organ failure. She was transferred to the intensive care unit (ICU). Immunosuppression was discontinued because infection treatment was necessary and the native liver had already recovered sufficiently. After she had been treated for 19 days in the ICU, she recovered from her multiple organ failure. However, abdominal computerized tomography demonstrated the formation of pancreatic walled off necrosis and an abscess on the 20th day after ERC. We performed endoscopic ultrasonography-guided abscess drainage and repeated endoscopic necrosectomy. The walled off necrosis diminished gradually in size, and the symptoms disappeared. The patient was discharged on the 87th day after ERC. This is the 1st report of a case of acute necrotic pancreatitis and walled off necrosis that was successfully treated by endoscopic management after APOLT.

Six-Year Graft Survival After Partial Pancreas Heterotopic Auto-Transplantation: A Case Report

BACKGROUND

Long-term graft survival of partial pancreas auto-transplantation after total pancreatectomy has not been clarified. The clinical implications of repeat completion pancreatectomy for locally recurrent pancreatic carcinoma in the remnant pancreas after initial pancreatectomy also have not been clarified.

METHODS

We have previously reported a 61-year-old woman presenting with re-sectable carcinoma of the remnant pancreas at 3 years after undergoing a pylorus-preserving pancreaticoduodenectomy for invasive ductal carcinoma of the pancreas head. We also performed distal pancreas auto-transplantation with the use of a part of the resected pancreas to preserve endocrine function.

RESULTS

The patient was discharged at 20 days after surgery without any complications. She had been followed regularly in our outpatient clinic. She had been treated with S-1 as adjuvant chemotherapy; 72 months after the completion total pancreatectomy with distal partial pancreas auto-transplantation, the patient was alive without any evidence of the pancreatic carcinoma recurrence. The pancreas graft was still functioning with a blood glucose level of 112 mg/dL, HbA1C of 6.7%, and serum C-peptide of 1.2 ng/mL; and urinary C-peptide was 11.6 μg/d.

CONCLUSIONS

Our patient demonstrated that repeated pancreatectomies can provide a chance for survival after a locally recurrent pancreatic carcinoma if the disease is limited to the remnant pancreas. An additional partial pancreas auto-transplantation was successfully performed to preserve endocrine function. However, the indications for pancreas auto-transplantation should be decided carefully in the context of pancreatic carcinoma recurrence.

[Repeated Pancreatic Resections with Parenchymal Preservation for Pancreatic Metastases of Renal Cell Carcinoma--Report of a Case]

A 51-year-old man underwent right nephrectomy for renal cell carcinoma. Six months later, a solitary metastatic tumor was detected in the pancreatic tail and he underwent distal pancreatectomy and splenectomy. One year and 6 months after the initial resection, a solitary metastatic tumor was detected in the pancreas head, and he underwent partial pancreatectomy. A solitary metastatic tumor was detected again in the remnant pancreatic body 3 years and 10 months after the initial resection. Partial resection of the distal part of the remnant pancreas was performed. The patient remains alive and well with no evidence of remnant disease 4 years after the initial resection.

[Signet-Ring Cell Carcinoma of the Ampulla of Vater--Report of a Case]

A 62-year-old man presented with pruritus caused by obstructive jaundice. He was diagnosed with carcinoma of the ampulla of Vater and underwent pylorus-preserving pancreaticoduodenectomy. Histologic examination revealed signet-ring cell carcinoma without nodal metastasis. The patient underwent a partial resection of the small bowel for small bowel obstruction 38 months after the initial resection. Histologic examination disclosed signet-ring cell carcinoma at the surface of the resected small bowel, and the diagnosis of peritoneal recurrence was confirmed. He received oral S-1(100 mg/day) every other day for 14 months until bowel obstruction caused by peritoneal carcinomatosis became apparent. The patient died of the disease 58 months after the initial resection.

[A Case of Solitary Paraaortic Lymph Node Recurrence after Surgical Resection for Combined Hepatocellular and Cholangiocarcinoma]

A 46-year-old woman underwent right hemihepatectomy, cholecystectomy, and sampling of the hilar lymph nodes for combined hepatocellular and cholangiocarcinoma. She received oral S-1 after hepatectomy. However, her serum level of carcinoembryonic antigen gradually increased, and solitary paraaortic lymph node recurrence was detected on positron emission tomography-computed tomography 12 months after hepatectomy. The patient underwent paraaortic lymph node dissection. Histologic examination revealed solitary paraaortic lymph node metastasis composed of hepatocellular carcinoma. After paraaortic lymph node dissection, she was administered sorafenib, and she remains alive and healthy with no evidence of disease 17 months after the initial resection.

[A Case of Radical Resection for Locally Advanced Pancreatic Cancer with Positive Peritoneal Cytology Treated with Chemoradiotherapy]

A 54-year-old female patient was admitted with obstructive jaundice. The patient was diagnosed with locally advanced unresectable pancreatic cancer of the head with invasion to the super mesenteric artery and the third portion of the duodenum. A biliary- and gastric-enteric bypass surgery was performed, and peritoneal lavage cytology was positive during surgery. After 6 courses of gemcitabine and S-1 combination chemotherapy, the CA19-9 level was normalized and the primary tumor shrank to 79% of its original size. Diagnostic laparoscopy revealed that distant metastasis was not detected and the peritoneal lavage cytology was negative. After additional chemoradiation therapy, a pancreaticoduodenectomy was perfomed. Microscopic investigation revealed that about 60% of the cancer tissue had been replaced by fibrosis and no cancer cells were found at the surgical margin. The patient was alive with no evidence of recurrence 17 months after radical surgery.