Giant insulinoma: report of a case and review of published reports.

BACKGROUND: Larger insulinomas are reportedly more likely to be malignant; however, their biological behavior has not been clearly elucidated. We here report the characteristics and treatment of a giant insulinoma with local invasion and lymph node metastasis. We also review published reports concerning the clinical features of giant insulinomas and comparing their grading with that of pancreatic neuroendocrine tumors. CASE PRESENTATION: A 71-year-old man was referred to our hospital for investigation of persistent hypoglycemia. On the current presentation, laboratory tests showed serum glucose, immunoreactive insulin, and C peptide concentrations of 45 mg/dL, 17.2 µIU/mL and 4.1 ng/mL, respectively. Dynamic magnetic resonance imaging showed a hypervascular tumor measuring 13.5 cm in the head of the pancreas. Computed tomography scanning demonstrated local invasion and lymph node involvement. He thus had Whipple's triad, which is associated with malignant insulinoma. No distant metastases having been identified, pancreaticoduodenectomy was performed. Intraoperatively, three separate tumors were identified in the pancreatic head. Pathological examination showed all three tumors were pancreatic neuroendocrine tumors; the tumor cells in the largest mass were strongly immunoreactive for insulin. The Ki-67 index was 2-5% in most parts of the largest tumor and over 20% in the poorly differentiated areas. This tumor was classified as neuroendocrine carcinoma in accordance with the 2010 World Health Organization classification of pancreatic endocrine neoplasms. He remains free of evidence of recurrence 2 years postsurgery. A review of published reports indicated that giant insulinomas are more malignant than smaller ones, and metastatic disease is found on presentation in 56% of patients with giant insulinomas; however, we were unable to identify any correlation between grade of pancreatic neuroendocrine tumor and biological behavior of giant insulinomas. CONCLUSIONS: Giant insulinomas more frequently exhibit malignant behavior, such as local invasion, lymph node involvement, and liver metastasis, than smaller ones. However, there was no relationship between grade and rate of metastases or survival in this small case series. Identification of useful biological markers is necessary.

Primary gastrointestinal stromal tumor of the liver: a case report and review of the literature.

BACKGROUND: Recently, gastrointestinal stromal tumors that have developed outside of the digestive tract have been reported. These tumors are collectively termed extra-gastrointestinal stromal tumors. Extra-gastrointestinal stromal tumors can also develop in the liver. Only eight case reports involving primary GIST of the liver have been published. We report a case and review the literature regarding this disease. CASE PRESENTATION: A 70-year-old woman with a past history of gastric cancer visited our hospital for regular inspection. With extensive radiological imaging, a computed tomography scan revealed a mass with a size of 6.8 cm in the lateral segment of the liver. (18)F-Fluoro-2-deoxyglucose positron emission tomography revealed no other malignancies except for the liver tumor. Because the lesion was suspected of being a primary malignant hepatic tumor, lateral segmentectomy was performed. The immunohistochemical analysis supported the diagnosis of gastrointestinal stromal tumors in the liver. The patient has had no evidence of recurrence during the 10-month follow-up period; imatinib chemotherapy was not administered. CONCLUSIONS: Primary hepatic gastrointestinal stromal tumors had no characteristics that distinguished them from ordinary tumors in imaging examinations. Primary gastrointestinal stromal tumors might have developed from interstitial Cajal-like cells.

[An elderly case of post-gastrectomy aspiration pneumonia following an influenza virus A infection].

A 85-year-old female was admitted to our hospital because of a fever and unconsciousness. Three days prior to admission, she had been diagnosed to have influenza A, and oseltamivir was therefore prescribed. The symptoms due to the influenza infection, including the fever, thereafter rapidly resolved. She regularly took 10 mg zopiclone for insomnia before sleeping. On the day of admission, she was drowsy with fever. Chest radiography showed bilateral massive infiltration of the lungs. Chest CT images revealed multilobar and nodular infiltration on both lungs. She underwent the partial gastrectomy 10 years ago due to the gastrointestinal bleeding. After that, gastro-esophageal reflux syndrome was occurred in the patient. A bronchoscope was easily inserted into the trachea without anesthesia. Aspirated saliva was found in trachea. Based on her post-gastrectomy state, post-gastrectomy aspiration pneumonia was diagnosed. Sulbactam/ampicillin (SBT/ABPC) (6 g) was administered daily, which led to reduced inflammatory responses and lung infiltration. Although influenza itself is sometimes critical for the elderly, careful attention should be paid to subsequent bacterial infections in patients who are at risk for developing aspiration pneumonia.