Human epidermal growth factor receptor 2 expression in mixed gastric carcinoma

AIM: To investigate human epidermal growth factor receptor 2 (HER2) amplification and protein expression in mixed gastric carcinoma.

METHODS: Fluorescence in situ hybridization and immunohistochemistry were used to detect HER2 amplification and protein expression in 277 cases of mixed gastric carcinoma. Protein staining intensity was rate as 1+, 2+, or 3+.

RESULTS: Of the 277 cases, 114 (41.2%) expressed HER2 protein. HER2 3+ staining was observed in 28/277 (10.1%) cases, 2+ in 37/277 (13.4%) cases, and 1+ in 49/277 (17.7%) cases. A HER2 amplification rate of 17% was detected, of which 25/28 (89.3%) were observed in the HER2 3+ staining group, 17/37 (45.9%) in 2+, and 5/49 (10.2%) in 1+. Of the 47 patients with HER2 amplification who received chemotherapy plus trastuzumab, 22 demonstrated median progression-free and overall survivals of 9.1 mo and 16.7 mo, respectively, which were significantly better than those achieved with chemotherapy alone (5.6 mo and 12.1 mo, respectively) in 19 previously treated patients (Ps < 0.05).

CONCLUSION: HER2 detection in mixed gastric carcinoma displays high heterogeneity. Relatively quantitative parameters are needed for assessing the level of HER2 amplification and protein expression.

Pancreatic adenocarcinosarcoma of monoclonal origin: A case report

Adenocarcinosarcoma, a neoplasm containing both carcinomatous and sarcomatous components, is a rare form of a cancer and the pathophysiology is currently poorly understood. Moreover, definitive treatment guidelines for this disease have not yet been established. Pancreatic adenocarcinosarcoma is even more rare and the prognosis is fatal. Here, we report a case of a 77-year-old male with pancreatic adenocarcinosarcoma and metastasis to the liver. The patient presented at our hospital with uncontrolled glucose levels and diabetes mellitus. The patient’s laboratory findings were unremarkable with the exception of elevated carbohydrate antigen 19-9 levels. Biopsies of the tumors in the pancreas and the liver revealed two types of tumors: pancreatic adenocarcinoma and a poorly differentiated sarcoma. To determine if KRAS mutations were present, we performed a peptide nucleic acid (PNA) clamp PCR-based assay. DNA sequencing by PNA clamp PCR identified a point mutation in codon 12 of exon 2 within KRAS from both tumor types. Because the KRAS mutation is observed in both tumor components, our findings support a monoclonal tumor origin followed by subsequent divergent differentiation into the sarcomatous and carcinomatous tumor populations. After we considered the patient’s status and the late stage of tumor detection, gemcitabine chemotherapy was administered.

Intraabdominal desmoplastic small round cell tumor: results of ifosfamide-based chemotherapy

Intraabdominal desmoplastic small round cell tumor (IDSRT) is a rare neoplasm, which is malignant and typically occurs in young adults. Although IDSRT is chemotherapy-sensitive, most cases do not achieve a complete response (CR). Even if some cases achieve a CR, they often relapse and result in poor prognosis. We report two cases of IDSRT, in a 24-year-old man and a 23-year-old man, who were treated with ifosfamide-based chemotherapy. Case 1, a 24-year-old man, presented with an abdominal mass, and the diagnosis of the biopsy specimen at laparoscopy was IDSRT. He received 7 courses of ifosfamide-based chemotherapy, which obtained a partial response (PR). He had no surgical resection, except for the biopsy procedure, and he underwent a total of 21 courses of chemotherapy. He died 36 months after diagnosis because of tumor regrowth and peritoneal bleeding. Case 2, a 23-year-old man, whose biopsy material allowed a diagnosis of IDSRT, was treated with 18 courses of chemotherapy, using ifosfamide, that resulted in a PR. This was followed by resection of the abdominal lesions, and he received an additional 2 courses of adjuvant chemotherapy. Four months after, completion of these 2 courses, the tumor recurred, and he died of diffuse pulmonary metastasis 36 months after diagnosis. This case report examines the results of ifosfamide-based chemotherapy in our two patients.

Pharmacokinetics of irinotecan and its metabolites SN-38 and APC in children with recurrent solid tumors after protracted low-dose irinotecan

Irinotecan (IRN), a topoisomerase I interactive agent, has significant antitumor activity in early Phase I studies in children with recurrent solid tumors. However, the disposition of IRN and its metabolites, SN-38 and APC, in children has not been reported. Children with solid tumors refractory to conventional therapy received IRN by a 1-h i.v. infusion at either 20, 24, or 29 mg/m2 daily for 5 consecutive days for 2 weeks. Serial blood samples were collected after doses 1 and 10 of the first course. IRN, SN-38, and APC lactone concentrations were determined by an isocratic high-performance liquid chromatography assay. A linear four-compartment model was fit simultaneously to the IRN, SN-38, and APC plasma concentration versus time data. Systemic clearance rate for IRN was 58.7 +/- 18.8 liters/h/m2 (mean +/- SD). The mean +/- SD ng/ml x h single-day lactone SN-38 area under the concentration-time curve (AUC(0-->6) was 90.9 +/- 96.4, 103.7 +/- 62.4, and 95.3 +/- 63.9 at IRN doses of 20, 24, and 29 mg/m2, respectively. The relative extent of IRN conversion to SN-38 and metabolism to APC measured after dose 1 were 0.49 +/- 0.33 and 0.29 +/- 0.17 (mean +/- SD). No statistically significant intrapatient difference was noted for SN-38 area under the concentration-time curve. Large interpatient variability in IRN and metabolite disposition was observed. The relative extent of conversion and the SN-38 systemic exposure achieved with this protracted schedule of administration were much greater than reported in adults or children receiving larger intermittent doses.