Can long-term follow-up strategies be determined using a nomogram-based prediction model of malignancy among intraductal papillary mucinous neoplasms of the pancreas?

OBJECTIVES: This study investigated whether a risk assessment nomogram can predict the malignant potential of intraductal papillary mucinous neoplasms (IPMNs) and provide valuable information for the follow-up and counseling strategies of such patients. METHODS: We studied 126 of 589 patients with IPMN who were followed up for at least 36 months with annual endoscopic ultrasonography. We analyzed scores derived from our nomogram, incorporating the parameters of sex, lesion type, mural nodule height, and pancreatic juice cytology determined at the initial IPMN evaluation. RESULTS: The rate of malignant IPMNs was 5.5% (7/126). The initial average nomogram score was 19.8 (range, 0-55), and the final follow-up average was 23.8 (range, 0-109). When a cutoff score was set at 35 points, the sensitivity, specificity, and accuracy of the nomogram to assess malignancy risk were 87.5%, 96.6%, and 96%, respectively. The area under the receiver operating characteristic curve of malignant IPMN prediction during follow-up was 0.865. CONCLUSIONS: The ability of the nomogram to predict malignancy in patients with IPMN was validated. Our findings can suggest that a follow-up for patients at high and low risk for cancer progression could be scheduled every 3 to 6 and 12 months, respectively.

Clinical characteristics of adenosquamous carcinoma of the pancreas: a matched case-control study.

OBJECTIVES: Adenosquamous carcinoma of the pancreas (ASC) is a variant of pancreatic ductal adenocarcinoma (PDAC), but the prognosis remains unclear. The purpose of this study was to clarify the prognosis of ASC using a matched case-control design. METHODS: We evaluated clinical characteristics of ASC treated between 2001 and 2011 in our institution. As controls, PDAC cases matched with ASC cases for sex, age, pretreatment Eastern Cooperative Oncology Group performance status, location, initial therapy and American Joint Committee on Cancer TNM staging for pancreatic cancer were also evaluated. RESULTS: Of the 914 cases of pancreatic neoplasm, 28 cases (3.06%) of ASC were identified, and 56 cases of PDAC were matched as controls. Median overall survival (OS) was significantly worse for ASC (8.38 months) than for PDAC (15.75 months; hazard ratio [HR], 1.94; 95% confidence interval, 1.07-3.51; P = 0.026). Of the 22 unresected cases, median OS was again significantly worse for ASC (4.67 months) than for PDAC (12.36 months; HR, 2.39; 95% confidence interval, 1.27-4.51; P = 0.007). CONCLUSION: These results demonstrate that ASC is more aggressive than PDAC.

Evaluation of Ki-67 index in EUS-FNA specimens for the assessment of malignancy risk in pancreatic neuroendocrine tumors.

BACKGROUND AND STUDY AIM: Malignancy in pancreatic neuroendocrine tumors (PNETs) is graded by assessing the resected specimens according to the World Health Organization (WHO) 2010 criteria. The feasibility of such grading using endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) specimens remains unclear. The aim of this study was to ascertain the optimal method of measuring the Ki-67 index in EUS-FNA specimens, using resected specimens as the criterion standard. PATIENTS AND METHODS: A total of 58 consecutive patients diagnosed with PNETs between March 1998 and May 2011 were included. The study measured intratumoral Ki-67 index heterogeneity, concordance rates of PNET grading by EUS-FNA with grade of the resected tumor, optimal method of measuring the Ki-67 index in EUS-FNA specimens, and survival analysis based on EUS-FNA specimen grading. RESULTS: Intratumoral dispersion of Ki-67 index in resected specimens was 0.033 for Grade 1 and 0.782 for Grade 2 tumors (P<0.001). Concordance rates for WHO classification between EUS-FNA and resected specimens were 74.0% using the mean Ki-67 index in EUS-FNA specimens and 77.8% using the highest Ki-67 index. The concordance rate rose to 90% when EUS-FNA samples with less than 2000 tumor cells were excluded (26% of EUS-FNA cases). The Kaplan-Meier survival curves were significantly stratified by the EUS-FNA grading of PNETs with 5-year survival rates of 100%, 58.3%, and 0%, for Grade 1, Grade 2, and neuroendocrine carcinoma (NEC) tumors, respectively. CONCLUSIONS: Grading of PNETs by the highest Ki-67 index in EUS-FNA specimens with adequate cellularity has a high concordance with grading of resected specimens, and can predict long term patient survival with high accuracy.

[Clinicopathological features of 8 patients with metastatic gastric tumors].

We examined the clinicopathological features of metastatic gastric tumor, using 9 tumors of 8 patients. Histological diagnosis with all biopsy specimens were adenocarcinoma. Most of the metastatic sites were located in the middle or upper gastric corpus. Endoscopic features of the lesion showed a submucosal tumor-like (5 cases) and primary gastric cancer-like (3 cases) appearance. Immunohistochemical staining of cytokeratins, TTF-1, surfactant protein, ER, or MGB1 identified the primary site; 6 in the lung and 2 in the breast. One case was diagnosed based on the EGFR mutation analysis. In conclusion, immunohistochemical staining and molecular method are useful tools to distinguish metastatic gastric tumor from primary gastric cancer.