Surgical site infection (SSI) is one of the severe complications in thoracic surgery. Skin sealants are skin microbe sealants that physically confine the skin microflora that remains after disinfection, and they have the effect of preventing bacterial migration and expression, thus preventing SSI. There have been some reports that a skin sealant is effective for preventing SSI in cardiovascular surgery and orthopedic surgery. However, in thoracic surgery, its usefulness is still unknown. In 146 cases of thoracotomy surgery under standard sterilization from September 2012 to March 2013, there were 107 cases with risk factors for SSI onset, of which 7 developed SSIs. Therefore, skin sealants were used in 30 cases that were judged as at risk for SSI from among 120 cases of thoracotomy from April 2013 to September 2013. Similar to the 107 cases, the 30 cases were high-risk cases for SSI onset, but no SSI cases were observed. It has been suggested that skin sealants may also decrease the incidence of SSI in the field of thoracic surgery.

Patients with acute diffuse peritonitis due to lower gastrointestinal perforation have an extremely high rate of postoperative surgical site infection (SSI), and if this occurs, the wound takes a long time to heal. In our hospital, rather than closing such wounds immediately with skin sutures, since 2014 we have been providing local negative-pressure wound therapy (NPWT) for open wounds and carrying out delayed primary closure at a later date as a measure to prevent SSIs. Of the 53 patients who underwent emergency surgery for acute diffuse peritonitis due to lower gastrointestinal perforation in our hospital between February 2014 and December 2018, 27 underwent postoperative NPWT (Group A), and 26 underwent primary skin suturing as part of the original surgery (Group B). Single-stage double-layer suturing was performed for patients in Group B. There were 4 SSI cases (14.8%) in Group A and 9 (34.6%) in Group B. The mean time to delayed primary suturing in Group A was 9.0 days. Our experience with the use of NPWT suggests that it may be useful for preventing wound SSIs.

The open new simplified totally extraperitoneal (ONSTEP) technique is a technique for the repair of inguinal hernia through the anterior approach. This technique places the mesh in the preperitoneal space medially and between the internal and external oblique abdominis muscles laterally. It has been performed in our country as a novel technique since November 2016. We have also introduced the technique as a day-surgery since 2017 and experienced a total of 367 lesions in 345 patients for two years. Recurrence occurred in only one case (0.27%). Complications included subcutaneous hemorrhage in eight cases, hematoma in three, seroma in four, surgical wound infection in two, and mesh infection in one. No serious complications such as postoperative intestinal obstruction, chronic pain and bladder injury were encountered. The mean operating time was 26 ± 7 min. Since the ONSTEP technique does not require any technique for dissecting the lateral preperitoneal space, it shortens the operating time compared with other transinguinal preperitoneal repairs (TIPP). From these findings, the ONSTEP technique appears to be a simple and highly safe technique that can be used as a day-surgery. We should wait accumulation of clinical experiences as to the long-term results, but we have gained favorable short-middle term results.

Local wide excision with axillary lymph node dissection is the standard procedure for axillary accessory breast cancer, though some literatures report that no axillary lymph node metastasis is found in >50% of all accessory breast cancer cases. To reduce the risk of upper limb and shoulder joint disorders and to maintain patients' quality of life, we consider rationale to perform sentinel lymph node biopsy instead of axillary lymph node dissection, if it is possible.

Here, we report a case of axillary accessory breast cancer in which local wide excision with sentinel lymph node biopsy was performed. We also investigated the indication of sentinel lymph node biopsy for accessory breast cancer and reviewed the literature.

A 74-year-old woman noticed a hard mass measuring 1.5 cm in diameter in her right axilla. A close examination led to the diagnosis of right axillary accessory breast cancer with no lymph node metastasis. We performed a local wide excision and sentinel lymph node biopsy, using two methods : radioisotope method and dyeing method. We confirmed the presence of sentinel lymph nodes in the right axilla with the radioisotope method and then performed surgery. Since no metastasis was confirmed in the sentinel lymph nodes, we could omit additional axillary lymph node dissection.

A 53-year-old woman presented to the hospital to have a detailed examination and treatment of a 20-cm cancer of the right breast with skin invasion and necrotic ulcer. Distant metastasis was not detected but axillary lymph node metastasis was found. The blood test showed an abnormally high WBC count of 47,200/μL. Although inflammatory findings were scarce, the serum G-CSF was measured to be abnormally high. Chemotherapy was initiated for the locally advanced breast cancer, but it became difficult to continue therapy due to bleeding from the cancer and protein leakage. Therefore, primary cancer resection and lymphadenectomy were performed for local control and quality of life improvement. The pathological findings revealed a metaplastic breast cancer with HER2 protein overexpression and anti-G-CSF antibody-positive chondroid differentiation. G-CSF-producing breast cancer has a high biological malignancy and poor prognosis. This is the first report of G-CSF-producing breast cancer with HER2 overexpression and chondroid differentiation.

We experienced difficulty in differentiating tuberculous lymphadenitis of the supraclavicular lymph nodes from breast cancer metastasis in two cases.

Case 1 : A 63-year-old woman presented to our hospital with a lump on her left clavicle. Chest computed tomography showed a swelling of the left supraclavicular lymph nodes and a left mammary tumor. We performed a core needle biopsy and ultrasonography of the tumor and lymph nodes, respectively. The patient was diagnosed with left breast cancer (cT1N0M0 cStage I) and tuberculous lymphadenitis via imaging and pathological findings. She started taking anti-tuberculosis drugs for tuberculosis and underwent surgery for breast cancer.

Case 2 : At another hospital, a 77-year-old woman received endocrine therapy for left breast cancer (cT4N3M1(LYM) cStage IV) with right supraclavicular lymph node metastasis. When she was transferred to our hospital during her treatment, we noted a mass in her left breast and swelling of the right supraclavicular lymph node. Since we recognized that she had gradually developed resistance to endocrine therapy and because there were no other metastases, we performed left mastectomy and right supraclavicular lymph node excision. No metastasis was found in the lymph node, and tuberculous lymphadenitis was diagnosed.

Case 1. A 64-year-old woman was diagnosed with right breast cancer, ER negative and HER2 positive. Metastasis to the transverse colon was suspected by CT scan and severe stricture of the lumen was confirmed by colonoscopy. To prevent bowel obstruction, laparoscopic partial colectomy (transverse colon) was performed and colonic metastasis of breast cancer was diagnosed. The patient has been receiving postoperative medical regimen and is alive without having gastrointestinal symptoms as of 3 years and one month after the operation. Case 2. A woman who was 68 years old when she had first presented to our hospital underwent left mastectomy with axillary lymph node dissection for Stage I left breast cancer (ER positive and HER2 negative). CT scan conducted 10 years and 2 months after the mastectomy suggested descending colon metastasis from breast cancer. Colonoscopy revealed severe stricture of the lumen of the colon. To prevent intestinal obstruction, laparoscopic partial colectomy (descending colon) was performed and colonic metastasis of left breast cancer was diagnosed. After the operation she has been on endocrine therapy and is alive without intestinal symptoms, as of 2 years after the operation. Solitary colonic metastasis of breast cancer can be managed by local resection and medical treatment that might allow the patient to escape from intestinal symptoms and to live long.

The patient was a 56-year-old female who had subtotal esophagectomy and ileocolic reconstruction for esophageal cancer (pT1bN0M0, Stage I) two years previously. A small tumor at the anterior mediastinum was unexpectedly found by a follow-up enhanced CT scan and it gradually enlarged with time. Further examination including EUS-FNA for the ileum used for reconstruction could not make diagnosis and a possibility of recurrence of esophageal cancer could not be ruled out, so we performed operation for diagnostic treatment. Histopathological examination showed a desmoid tumor. No signs of recurrence have been seen.

Desmoid tumors are considered benign and, therefore, carry no malignant potential ; they never metastasize. However, they tend to infiltrate into the adjacent tissue. Although there are many cases of mesenteric desmoid tumor after abdominal surgery, desmoid tumor arisen in the ileum mesentery after reconstruction has not been described in the literature. We must bear in mind that a desmoid tumor can affect the ileum used for reconstruction.

Rhabdomyolysis is a reported adverse event of TS-1. The case of a patient with rhabdomyolysis believed to have been caused by TS-1 is presented. A 74-year-old man had previously taken oral medication for diabetes and hypertension, but he was not currently taking any such medication. He had undergone total gastrectomy, D2 lymph node dissection, and Roux-en-Y reconstruction for gastric cancer 18 months previously. The pathological diagnosis was T3 (SS) N0(0/52) H0 P0 CY0 M0 Stage IIA. From postoperative Day 42, postoperative adjuvant chemotherapy was started with TS-1 on a schedule of 2 weeks' oral administration and 1 week drug holiday. The patient was able to tolerate this regimen with no obvious adverse events. In Month 15 of this treatment, which had been continued at the patient's request, he became aware of generalized loss of muscle strength and weakness in the legs. He became unable to walk and was examined on Day 2 after the symptoms appeared. Abnormal blood test results were WBC 23,600/μl, LDH 544 U/l, CK 20,052 U/l, and CRP 26.7 mg/dl, and blood and urinary myoglobin were both elevated, at 360 ng/ml and 2,800 ng/ml, respectively. Rhabdomyolysis was diagnosed on the basis of these results. The symptoms improved after the patient was admitted for intravenous therapy, and he was discharged improved on Day 11. This case of rhabdomyolysis during treatment with oral TS-1 is reported, together with a discussion of the literature.

(Case 1) A 76-year-old man was treated for prostate cancer. Follow-up computed tomography (CT) revealed a heterogeneous tumor at the border between the stomach wall and lesser omentum. The tumor demonstrated 18-F-fluorodeoxyglucose (FDG) uptake, with a maximum standardized uptake value (SUVmax) of 3.7. Colonoscopy revealed a simultaneous rectal adenoma with surgical indication. We performed laparoscopic resection of the tumor located in the lesser omentum and laparoscopic low anterior resection. The tumor in the lessor omentum was 60 mm in diameter and was fed by the left gastric artery. We were able to resect the whole tumor without breakage, and it was histologically diagnosed as a gastrointestinal stromal tumor (GIST) of the lesser omentum.

(Case 2) A 65-year-old woman underwent a complete medical checkup, in which laboratory examination showed a high level of serum CA19-9. CT revealed an irregularly shaped, heterogenous bulky mass located on the ventral side of the gastric body. FDG positron emission tomography revealed FDG accumulation, with an SUVmax of 4.9. Endoscopic ultrasound - guided fine - needle aspiration biopisy was performed ; based on the results, we diagnosed a GIST that was weakly positive for c-kit and positive for CD34. Due to the size, we performed laparotomy. The tumor was 150 mm in diameter and located in the lesser omentum. There was an adhesion with the stomach wall and greater omentum that did not combine with the gastric wall. We were able to completely resect the specimen without breakage.

Cases 1 and 2 both involved high-risk GISTs of the lesser omentum. Although the patients refused adjuvant chemotherapy, patients 1 and 2 have been living without recurrence for 31 months and 109 months, respectively.

A 68-year-old man underwent distal gastrectomy and D2 dissection for early gastric cancer in 2004. It was histopathologically diagnosed as T1b (SM), N2 (7, # 4d, 5, 6, 8a), ly0, v0, stage II, according to the Japanese Classification of Gastric carcinoma, 13th edition. Twelve years later, he visited a local doctor because of back pain and was referred to our hospital due to an increased serum alkaline phosphatase. Computed tomography (CT) showed osteogenic changes in the spine and pelvic bone, and FDG-positron emission tomography (PET) showed high FDG accumulation in the bones. Biopsy from the spine showed adenocarcinoma that was considered metastasis of gastric cancer because its histology was similar to that of the resected gastric cancer, positive for human gastric mucin and negative for prostate-specific antigen. Early gastric cancer can recur to bone more than 10 years after resection.

The patient was a 62-year-old male, who presented with a one-week history of fever while receiving chemotherapy for multiple myeloma. Abdominal CT demonstrated an abscess around the ileocecal area and rupture of the appendix. An emergency laparotomy was performed with the suspected diagnosis of perforated appendicitis. The appendix was enclosed in the abscess on the dorsal side of the ileocecum, and ileocecal resection was performed. Postoperatively, the low-grade fever and diarrhea persisted. Serum test for cytomegalovirus (CMV) antigen prior to surgery came back positive. Based on this result, the patient was finally diagnosed as having CMV enteritis and started on treatment with valganciclovir. Both fever and diarrhea improved within a few days after the start of valganciclovir treatment. Histopathologically, a deep ulcer perforating the terminal ileum, with abscess formation was noted. CMV-infected cells were identified in the tissue around the ulcer. From the clinical course and histopathological findings, we made the final diagnosis of CMV enteritis with perforation of the ileum and secondary rupture of the appendix. In this case, it was difficult to differentiate the actual diagnosis from primary perforated appendicitis prior to the surgery. In regard to gastrointestinal perforation in immunocompromised patients, it is necessary to bear in mind the possibility of CMV enteritis, even though it is an extremely rarely encountered condition. Prompt serological testing for CMV antigenemia is useful for early diagnosis and treatment.

Negative pressure wound therapy (NPWT) effectively promotes wound healing ; however, it is contraindicated for the management of enterocutaneous fistula. We describe two cases of an open wound associated with an enterocutaneous fistula treated with NPWT. The exposed bowel was protected with non-adhesive gauze following drainage and closure of the fistula, and this strategy led to significantly improted wound healing.

Case 1 : A 67-year-old woman who underwent Hartmann's procedure for a perforated sigmoid colon diverticulum developed wound dehiscence secondary to colon stump necrosis. The exposed bowel was covered and protected with nonadhesive gauze prior to NPWT application.

Case 2 : A 65-year-old woman who underwent pelvic exenteration for radiation enterocolitis and rectal cancer developed midline wound dehiscence secondary to Procedure-induced bowel injury. The exposed bowel was covered and protected with nonadhesive gauze prior to NPWT application. In both cases, low suction pressure was used, and initially, we performed dressing exchanges on a daily basis. The suction pressure was gradually increased and the rate of exchange was reduced. Finally, uncomplicated wound healing occurred in both patients. We emphasize that NPWT can be safely performed even in open wounds with enterocutaneous fistula after ensuring that the exposed bowel is adequately protected following fistula closure.

A 70-year-old woman was referred to our hospital with complaints of high fever, abdominal pain, and loss of appetite. Abdominal computed tomography (CT) showed a giant multiple cystic tumor with a maximum diameter of about 25 cm in the mesentery of the right colon. She was diagnosed as having a huge mesenteric cyst. Since antibiotics were ineffective for relieving the abdominal pain, surgery was performed. However, a giant cyst was not confirmed, and a dark-red, hard mass of about 6 cm was found in the mesentery of the transverse colon. The mass was excised with partial resection of the transverse colon. Histological findings showed inflammatory cell infiltration with no malignant cells. Thus, the mass was diagnosed as an inflammatory pseudotumor. There has been no evidence of recurrence on follow-up. To the best of our knowledge, there is no prior report in the Japanese literature of a case of mesenteric inflammatory pseudotumor suspected to be due to rupture of a mesenteric cyst. Therefore, this case is reported as an example of a unique and very rare mesenteric inflammatory pseudotumor.

A 78-year-old man who was brought into our hospital by ambulance because of unconsciousness was admitted for the purpose of close exploration and treatment. Following abdominal CT scanning and double-balloon enteroscopy, a small bowel tumor was diagnosed. Laparoscopic partial excision of the small intestine was thus performed. The removed specimen included a 95 × 50 × 35 mm solid tumor which was negative for c-kit, CD34, DOG1, S-100, desmin, and calponin, and was partially positive for α-SMA, the Ki-67 index being 80%. The final diagnosis was poorly differentiated leiomyosarcoma of the small intestine. About 50 days later, he was diagnosed with recurrence and underwent resection of the tumor again. Then he experienced recurrence to the abdominal wall about 3 months and died of the disease about 4 months after the initial operation.

With a recent establishment of the diagnosis criteria for gastrointestinal mesenchymal tumors, relatively rare cases have been diagnosed as gastrointestinal leiomyosarcoma. As we experienced a case of a patient who revealed a high Ki-67 index and was diagnosed with small bowel leiomyosarcoma which had progressed so rapidly, the case is presented here.

Multiple small bowel metastases from cutaneous malignant melanoma with gastrointestinal bleeding are rarely treated surgically. Moreover, the procedure for the control of such bleeding has not been established. A case of malignant melanoma leading to gastrointestinal bleeding secondary to small bowel metastasis that was treated by intestinal resections is reported. A 70-year-old man presented with dizziness and palpitations. Abdominal enhanced computed tomography showed multiple small bowel tumors, swelling of the abdominal lymph nodes, and stones in the gallbladder. Laparoscopic lymph node biopsy and cholecystectomy were performed. Microscopic examination of the resected small bowel mesenteric lymph node specimen showed malignant melanoma. Furthermore, at the time of the operation, cutaneous black tumors were noted on the back. Based on these findings, multiple cutaneous and small bowel metastases from malignant melanoma were diagnosed. Subsequently, continuous gastrointestinal bleeding warranted frequent transfusions. Hemorrhagic scintigraphy showed the source of bleeding, and small bowel resections were performed. The patient's postoperative course was unremarkable. Hemorrhagic scintigraphy and small bowel resections were useful for the diagnosis and control of gastrointestinal bleeding secondary to small bowel metastases from cutaneous malignant melanoma. This enabled successful administration of immunotherapy and chemotherapy to the patient.

Neuroendocrine carcinoma is rare, with an incidence rate of 3 to 5 per 100,000 people. And its prognosis is considered to be poor. A 65-year-old woman was pointed out having both multiple hepatic nodules and a small bowel tumor by a follow-up ultrasonography for viral hepatitis type C. Pathological examination of a liver biopsy revealed that it was positive for AE1 / AE3, CD56, chromogranin A, and synaptophysin, and that the Ki-67 index was 66%. Based on these findings we finally diagnosed her disease as small bowel neuroendocrine carcinoma with multiple liver and lymph node metastases, multiple peritoneal and pleural dissemination. Because bowel obstruction developed, laparotomy was performed. The tumor was found at the end of the ileum, but it was unresectable because of direct invasion to the common iliac artery, common iliac vein and iliopsoas muscle. Subsequently we performed bypass surgery by ileo-transverse colon anastomosis. Since the pathological diagnosis of peritoneal dissemination, which was sampled at laparotomy, was metastasis of neuroendocrine carcinoma, the primary lesion was considered to have arisen in the ileum. She received VP-16 combined with CDDP and the therapeutic effect was PR. As to chemotherapy against unresectable small bowel neuroendocrine carcinoma, VP-16 and CDDP can be effective treatments, though standard treatment has not been established as yet.

A 41-year-old man presenting with fever and abdominal pain was found to have perforated acute appendicitis with abscess formation and a metallic foreign matter at the same site. By keeping an avoidance of extended surgery in mind, we decided to employ interval appendectomy (IA) and performed laparoscopic appendectomy after conservative therapy. To ensure the recovery of the foreign matter as well as to treat the appendiceal root, we performed the treatment and transection of the root outside of the peritoneum and under the direct vision by mobilizing the ileocecal region. We recovered the about 7-mm metallic foreign matter. His postoperative course was uneventful. Although we sometimes encounter clinical cases of appendicitis due to a foreign matter, those in which laparoscopic surgery, especially IA, was performed are rare. Ours is of the first domestic case in which IA was successfully done as far as we could review.

Recently a variety of advantages of IA have been advocated for acute appendicitis with locally serious inflammation like our case, and IA is one of promising therapeutic strategies. However, the indication of IA for acute appendicitis caused by a foreign matter has rarely been reported and resultantly its effect is still unknown. As this case appears to be important in terms of the indication and usefulness of IA for acute appendicitis due to a foreign matter, we present the case with a review of the literature.

A 23-year-old woman was admitted to our hospital complaining of epigastric and right lower abdominal pain. Hematological examination at admission revealed evidence of a low-grade inflammatory response, with increase of the WBC count and serum CRP level. Abdominal USG showed an irregular hypoechoic mass measuring about 15 × 10 mm in size near the appendiceal root in the ileocecal region. Abdominal dynamic CT showed an irregular low-density mass measuring about 14 × 14 mm in diameter in the same region, showing delayed enhancement, and enlarged ileocolic lymph nodes measuring about 10 mm in diameter. Colonoscopy showed a 20-mm bulge that appeared to represent extramural compression by a mass on the cecal side of the ileocecal valve. However, biopsy of the mass in the region of the ileocecal valve revealed no evidence of malignancy. Taken together, based on the preoperative imaging and other findings, the patient was diagnosed as having an appendiceal mucocele. Laparoscopic ileocecal resection was performed, with D3 lymph node dissection, as malignancy could not be excluded owing to the enlarged lymph nodes. Macroscopic examination of the resected specimen revealed a yellow tumor measuring about 10 × 10 × 3 mm in size in the appendiceal lumen, and histological examination revealed numerous foam cells in the appendiceal submucosa.

Xanthogranulomatous inflammation is most often observed in the gallbladder or kidney, and xanthogranulomatous appendicitis is extremely rare. This disease is of particular clinical significance as it is difficult to differentiate from appendiceal cancer. This case serves to underscore the importance of bearing in mind the possibility, even if remote, of xanthogranulomatous appendicitis in patients presenting with appendiceal tumors.

An 88-year-old woman presented to our hospital because of a 2-day history of abdominal pain and nausea. An abdominal CT scan revealed a small intestine thickened like an edema in the right lower quadrant of abdomen. A narrowing portion was identified at the transitional part from the dilated small intestine to the thickened intestine. We suspected strangulated ileus and performed emergency laparoscopic operation. Observation of the abdominal cavity revealed the small intestine invaginating dorsally through a defect in the ascending mesocolon. Hiatal hernia of the ascending mesocolon was diagnosed. Since the invaginated small intestine could not be reduced with traction, the hiatus was incised to enlarge the defect and the ileum 70 cm to 100 cm distal to the Bauhen valve was reduced into the abdomen. No ischemic change was observed in the invaginated small intestine, so that no bowel resection was needed. We present a case of hiatal hernia of the ascending mesocolon, an extremely rare entity, which was diagnosed laparoscopically and was performed reduction of the incarceration and closure of the hiatus.

A 43-year-old woman presented with diarrhea and abdominal pain. Physical examination showed elevated body temperature (37.8°C), and palpation revealed tenderness across her upper abdomen. Laboratory investigations revealed an elevated serum C-reactive protein level of 22 mg/dL. Abdominal computed tomography revealed markedly dilated colonic loops between the right diaphragm and liver, and a whirl sign in the left upper abdomen suggested colonic volvulus. Emergency colonoscopy revealed mucosal necrosis of the dilated colon, and an emergency operation was performed for a diagnosis of colonic volvulus accompanying Chilaiditi syndrome. The descending colon was not attached to the retroperitoneum ; therefore, the patient was diagnosed with a persistent descending mesocolon. Left hemicolectomy (including removal of the dilated colon) was performed, and the patient's postoperative course was unremarkable. Interposition of the proximal jejunum between the small intestinal mesocolon and transverse colon led to intestinal obstruction soon after discharge ; however, intestinal obstruction was successfully treated with conservative treatment. We report a case of persistent descending mesocolon accompanying colonic volvulus in Chilaiditi syndrome, followed by Chilaiditi syndrome presenting with small intestinal involvement.

A 60-year-old woman who had undergone right hemicolectomy for Stage IIIa adenocarcinoma of the ascending colon with regional lymph node metastasis received a follow-up colonoscopy 7 months after the operation. It disclosed a 6-mm type Ip polyp at the sigmoid colon. Consequently, endoscopic submucosal resection was performed. The histopathological diagnosis was IgG λ type extramedullary plasmacytoma. Since the surgical stump was positive, sigmoidectomy with regional lymph node dissection was performed. We did not identify histopathological local tumor remnant nor lymph node metastasis. The patient has been alive without recurrence as of 112 months after the operation.

Extramedullary plasmacytoma of the colon is rare and this is the 10th case reported in Japan. Furthermore, this case is so rare that she had synchronous double cancer, namely colon cancer and extramedullary plasmacytoma of the sigmoid colon. It is known that extramedullary plasmacytoma is highly sensitive to radiation therapy. However, the therapeutic guidelines for the disease arisen in the colon recommend surgical resection as the first-line therapy, where we would have to achieve a complete resection as far as possible. This paper deals with our case, together with a review of the literature.

A 69-year-old woman was admitted to our hospital complaining of left shoulder and abdominal pain 2 days after she had a fall. She had been diagnosed, by abdominal CT performed 7 years earlier, as having a giant hepatic cyst measuring 25 × 18 × 12 cm in size, in the right lobe of the liver. She had remained asymptomatic and not received any treatment for the cyst. Abdominal CT at the present admission revealed a ruptured liver cyst. Because her general condition was good and physical examination revealed no evidence of peritoneal irritation, she was kept under close follow-up as an out-patient. After 5 days, her abdominal pain worsened and signs of peritoneal irritation became obvious. A diagnosis of acute generalized peritonitis due to rupture of the liver cyst was made and urgent laparoscopic surgery was performed. Intraoperatively, hemorrhagic ascites was noted, and unroofing of the cyst was performed. The postoperative course was uneventful and the patient was discharged on POD 8. Two years after this surgery, the patient visited us again complaining of back pain and fever. Hepatic cyst recurrence with cyst infection was suspected, which was treated by only percutaneous drainage. Since then, the patient has remained asymptomatic.

A 75-year-old woman was admitted to our hospital with right hypochondralgia and fever. The abdomen was flat and soft and there was tenderness in the right hypochondriac region. The laboratory tests revealed an elevation of CRP. Abdominal contrast-enhanced computed tomography revealed a 10-cm multilocular cyst in the medial segment of the liver. The drainage and antibacterial treatment to this cystic lesion suggestive of an infected hepatic cyst were ineffective. Therefore, we performed left hepatic lobectomy including the lesion. The resected specimen contained a 65×70×70 mm mucinous multilocular cystic tumor. Histopathological examination revealed that the tumor contained ovarian-like stroma, and there were no malignant components. We thus diagnosed the tumor as mucinous cystic neoplasm (MCN) of the liver. We report a case of MCN of the liver mimicking a liver abscess, together with a review of the literature.

A 38-year-old male was admitted in emergency following a blunt abdominal trauma in a car accident. Since abdominal contrast CT showed bleeding from the posterior superior pancreaticoduodenal artery, pancreaticoduodectomy (PD) was performed on the pancreatic head injury after hemostasis was echieved, with interventional radiology (IVR). Postoperatively, the patient developed both abdominal compartment syndrome and deviation of a pancreatic duct tube, resulting in an external pancreatic fistula. Thereafter, the patient underwent pancreaticogastrostomy 188 days post-injury and was successfully discharged. PD is required in cases of severe pancreatic head injury. The mortality of PD in pancreatic injury exceeds 15% and the frequency of complications is high, therefore careful judgement is necessary for its application. Following successful surgery, it is also common for a large volume of fluid to accumulate at the injury site, thus the risk of developing acute coronary syndrome (ACS) is high. Two-stage PD should also be considered to prevent complications. Preventive procedures such as intraoperative open abdominal management should also be considered to reduce mortality.

A 64-year-old woman presented with easy fatigue and abdominal distension ; initial laboratory analysis showed anemia, a low platelet count, and low prothrombin (PT) activity. She was diagnosed with a huge tumor (diameter, 25 cm) of unknown origin located below the right liver and above the right kidney that was mostly hypovascular on enhanced computed tomography (CT). Magnetic resonance imaging (MRI) showed a macular high and low-intensity area inside the tumor on T2-weighted images, suggesting hemorrhage at different time phases. ¹⁸F-FDG-positron emission tomography (PET)/CT showed no significant accumulation of ¹⁸F-FDG in the tumor. Considering these findings, the preoperative diagnosis of the tumor was a retroperitoneal chronic expanding hematoma (CEH), and it was resected. The tumor did not invade but adhered to surrounding structures, and blood transfusion was needed because of blood loss of 4 L, mainly from the exfoliated surface. Postoperative bile leakage was stopped conservatively, and the patient was discharged on postoperative day 13 with a normal platelet count and normal PT activity. Histopathology showed an extrarenal angiomyolipoma (AML), resulting in a huge retroperitoneal hematoma.

CEH and AML are both rarely found in the retroperitoneal cavity. A case of a huge retroperitoneal hematoma caused by AML with a preoperative blood coagulation disorder is presented along with a review of the literature.

A 41-year-old woman was examined at another institution for abdominal distension. She was referred to us with a lower abdominal mass. Computed tomography and magnetic resonance imaging showed a massive tumor extending from the lower surface of the liver to the pelvic cavity, and liposarcoma was suspected. Initial surgery was performed to resect as much of the tumor as possible, and a tumor measuring 400 × 290 × 170 mm and weighing 7,108 g was removed. Primary retroperitoneal malignant fibrous histiocytoma (now known as undifferentiated pleomorphic sarcoma) was diagnosed, and postoperative follow-up showed the recurrence of a mass measuring 105 × 65 × 105 mm in the right abdomen 30 months postoperatively. Surgery was subsequently performed each time the tumor regrew, and the patient underwent 12 operations during the 11-year period after onset. A few months after the final operation, rapid tumor growth occurred, and the patient died 134 months after the initial surgery. Undifferentiated pleomorphic sarcoma is a form of sarcoma that most commonly occurs in the soft tissue of the limbs, and since curative surgery is difficult, its prognosis is poor. Since recurrence is common, the role of cytoreductive surgery to improve symptoms is unknown. The case of a patient who underwent surgery 12 times and survived for the extended period of 11 years is reported, together with a discussion of the literature.