Role of pancreatic juice cytology in the preoperative management of intraductal papillary mucinous neoplasm of the pancreas in the era of international consensus guidelines 2012.

BACKGROUND: Routine endoscopic retrograde pancreatography (ERP) for pancreatic juice cytology (PJC) during management of intraductal papillary mucinous neoplasm (IPMN) is not recommended in the international consensus guidelines 2012. The aim of the present study was to investigate the roles of PJC in relation to the new stratification of clinical findings in the consensus guidelines 2012. METHODS: Medical records of 70 consecutive patients who underwent preoperative PJC, subsequent pancreatectomy, and a pathological diagnosis of IPMN were reviewed. Diagnostic ability of PJC to detect malignant lesions was calculated by the stratification of clinical findings. RESULTS: Forty patients had malignant lesions, including 29 with malignant IPMN, 10 with concomitant pancreatic adenocarcinoma, and one with both. Accuracies of PJC in all 70 patients and in 59 patients with IPMN alone were 77 and 80 %, respectively. The sensitivity and accuracy of PJC in patients with "worrisome features" were 100 and 94 %, respectively. Eight of 11 patients with concomitant pancreatic adenocarcinoma had non-malignant IPMN without risk factors, and 3 significant lesions could be diagnosed only by ERP/PJC. In addition, the management plan based on imaging study changed from observation to resection in two patients who had the single "worrisome feature" of branch duct IPMN and positive PJC results. As a result, PJC altered the management plan in 5 patients. CONCLUSIONS: Pancreatic juice cytology potentially has important roles to determine the adequate treatment choice in patients with IPMNs with "worrisome features," and to detect significant lesions that could not be detected by other imaging modalities.

Role of ERCP in the era of EUS-FNA for preoperative cytological confirmation of resectable pancreatic ductal adenocarcinoma.

PURPOSE: In patients with pancreatic ductal carcinoma (PDAC), EUS-FNA carries a risk of cancer seeding. To avoid this risk, we attempted to obtain preoperative cytological confirmation of adenocarcinoma by ERCP. The aim of this study was to assess the validity of our diagnostic strategy. METHODS: The medical records of 124 consecutive patients who were investigated for potentially resectable PDAC were retrospectively reviewed, and the ability to detect adenocarcinoma by ERCP was evaluated. RESULTS: ERCP was performed in 115 patients, 69 of whom had positive cytology results. Thirty-four patients underwent EUS-FNA, 29 of whom had positive cytology results. A total of 98 patients (79 %), therefore, had preoperative cytological confirmation of adenocarcinoma, which was more frequent in patients with lesions of the head of the pancreas than in those with lesions of the body or tail of the pancreas. The postoperative pathological diagnosis demonstrated malignant pancreatic neoplasms in 122 patients (98 %), including 111 with PDAC. EUS-FNA did not affect the rate of postoperative peritoneal dissemination. CONCLUSIONS: Our strategy using ERCP as the initial diagnostic modality for obtaining cytological confirmation of potentially resectable PDAC seems to be adequate, yielding a high rate of positive cytology, especially in cases with tumors of the head of the pancreas.

Reappraisal of bone and soft tissue cytopathology classification using the modified Milan system.

BACKGROUND: A standardized reporting system for bone and soft tissue tumor cytopathology has not yet been established. The objective of this study was to explore the potential utility of a classification modified from the Milan System for Salivary Gland Cytopathology and compared it with the upcoming World Health Organization (WHO) system for fine-needle aspiration of soft tissue lesions. METHODS: The authors reviewed 285 cytology cases of bone/joint (n = 173) and soft tissue (n = 112) lesions, scoring each within diagnostic categories. The results were compared with histologic diagnoses and the risk of malignancy (ROM) for each category, and diagnostic reliability was analyzed. RESULTS: All 285 cases were successfully classified into one of the following categories: nondiagnostic (6.3%), non-neoplastic (11.9%), atypia of uncertain significance (11.9%), benign neoplasm (5.6%), bone and soft tissue neoplasm of uncertain malignant potential (25.3%), suspicious for malignancy (1.4%), and malignant (37.5%). The ROM was 44.4% (eight of /18 cases) in nondiagnostic, 0% (zero of 34 cases) in non-neoplastic, 32.4% (11 of 34 cases) in atypia of uncertain significance, 0% (zero of 16 cases) in benign neoplasm, 16.7% (12 of 72 cases) in bone and soft tissue neoplasm of uncertain malignant potential, 75.0% (three of four cases) in suspicious for malignancy, and 100% (107 of 107 cases) in malignant categories. Using the WHO system, the proportion and ROM of the benign category (non-neoplastic and benign neoplasm) was 17.5% and 0%, respectively. Among benign and malignant lesions, the diagnostic accuracy, sensitivity, and specificity for detecting malignancy were 99.4%, 100%, and 98.0%, respectively. CONCLUSIONS: The modified Milan system as well as the WHO system may be a useful cytopathologic classification tool for both bone and soft tissue lesions.

Clinical importance of intraoperative peritoneal cytology in patients with pancreatic cancer.

BACKGROUND: The clinical importance of intraoperative peritoneal cytology in patients with pancreatic cancer remains incompletely understood. METHODS: Peritoneal washing samples were collected from 411 consecutive patients with pancreatic ductal adenocarcinoma from 1996 to 2014. Of the 411 patients, 335 underwent macroscopically curative resection and 76 with noncurative factors did not undergo resection. We compared long-term outcomes between patients with positive cytology (cytology+) and those with negative cytology (cytology-) and investigated the importance of clinicopathologic factors. RESULTS: Of 335 patients with curative resection, 300 (89.6%) were cytology- and 35 (10.4%) were cytology+. The median overall survival of cytology+ patients was less than that of cytology- patients (16 vs 31 months, respectively; P < .0001). The median overall survival of cytology+ patients with noncurative factors was significantly worse than that of cytology+ patients with curative resection (6.9 vs 16.0 months, respectively; P = .0023). The median disease-free survival of cytology+ patients was less than that of cytology- patients (6.5 vs 16 months, respectively; P < .0001). In the multivariate analysis, cytology+ was an independent prognostic factor for overall survival and disease-free survival. CONCLUSION: Cytology+ without noncurative factors was a predictive factor for a poor prognosis. Therefore, it is important to regard patients with pancreatic cancer characterized by cytology+ as a special group that may warrant more aggressive adjuvant therapy.

Highly sensitive and quantitative evaluation of the EGFR T790M mutation by nanofluidic digital PCR.

The mutation of T790M in EGFR is a major mechanism of resistance to treatment with EGFR-TKIs. Only qualitative detection (presence or absence) of T790M has been described to date, however. Digital PCR (dPCR) analysis has recently been applied to the quantitative detection of target molecules in cancer with high sensitivity. In the present study, 25 tumor samples (13 obtained before and 12 after EGFR-TKI treatment) from 18 NSCLC patients with activating EGFR mutations were evaluated for T790M with dPCR. The ratio of the number of T790M alleles to that of activating mutation alleles (T/A) was determined. dPCR detected T790M in all 25 samples. Although T790M was present in all pre-TKI samples from 13 patients, 10 of these patients had a low T/A ratio and manifested substantial tumor shrinkage during treatment with EGFR-TKIs. In six of seven patients for whom both pre- and post-TKI samples were available, the T/A ratio increased markedly during EGFR-TKI treatment. Highly sensitive dPCR thus detected T790M in all NSCLC patients harboring activating EGFR mutations whether or not they had received EGFR-TKI treatment. Not only highly sensitive but also quantitative detection of T790M is important for evaluation of the contribution of T790M to EGFR-TKI resistance.

Identification of intranuclear inclusions is useful for the cytological diagnosis of ovarian clear cell carcinoma.

OBJECTIVE: The aim of this study was to clarify the diagnostic significance of the presence of intranuclear inclusions in clear cell carcinoma (CCC). MATERIALS AND METHODS: We analyzed 98 imprint specimens and 53 ascites specimens from 98 ovarian carcinoma cases [28 CCCs, 37 serous carcinomas (SCs), 22 endometrioid carcinomas (ECs), and 11 mucinous carcinomas (MCs)]. We examined (1) frequency of intranuclear inclusion-positive cases of each ovarian carcinoma subtype, using imprint specimens, (2) frequency of intranuclear inclusion-positive cells of each ovarian carcinoma subtype, using imprint specimens, (3) frequency of intranuclear inclusion-positive cases of each ovarian carcinoma subtype, using ascites specimens, and (4) sensitivity and specificity of the presence of intranuclear inclusions for the cytological diagnosis of CCC. RESULTS: (1) The frequency of intranuclear inclusion-positive cases in CCC (96.4%) was significantly higher than in SC (13.5%), EC (13.6%), and MC (18.2%) (P < 0.001). Two or more intranuclear inclusions in a single nucleus were observed only in CCC. (2) The frequency of intranuclear inclusion-positive cells in CCC (median, 0.41%) was significantly higher than in non-CCC subtypes (0.010%) (P < 0.001). (3) Using ascites specimens, the frequency of intranuclear inclusion-positive cases in CCC (78.6%) was significantly higher than in SC (10.3%), EC (0%), and MC (0%) (P < 0.001). (4) The sensitivity of intranuclear inclusions was 96.4%, and the specificity was 85.7%. CONCLUSIONS: The identification of intranuclear inclusions, in particular a high frequency and multiple intranuclear inclusions in a single nucleus, is useful for the cytological diagnosis of CCC. Furthermore, these results may be applicable to ascites cytology.

Intraoperative irrigation cytology of the remnant pancreas to detect remnant distinct pancreatic ductal adenocarcinoma in patients with intraductal papillary mucinous neoplasm undergoing partial pancreatectomy.

BACKGROUND: Patients with intraductal papillary mucinous neoplasm (IPMN) of the pancreas may have concomitant distinct pancreatic ductal adenocarcinoma (PDAC). We evaluated the safety and usefulness of intraoperative irrigation cytology of the remnant pancreas (IICP) during pancreatectomy to detect remnant distinct PDAC in patients with IPMN. METHODS: The records of all 48 patients with IPMN who underwent IICP during partial pancreatectomy at our institution from April 2007 to March 2012 were reviewed retrospectively. After division of the pancreas, a 4-French tube was inserted into the main pancreatic duct of the remnant pancreas from the cut edge, and fluid for cytologic examination was obtained by saline irrigation through the tube. If the third IICP was positive, patients underwent additional pancreatic resection. Clinical and pathologic outcomes were evaluated. RESULTS: The third IICP was positive in 5 patients. Postoperative pathologic examination showed that these patients all had remnant distinct PDAC in the additionally resected specimen, which was not detectable on preoperative imaging examination or on intraoperative macroscopic examination, ultrasonography, or palpation. This PDAC was stage 0 in 4 patients and stage III in 1 patient. No procedure-related complications were observed. One patient developed peritoneal metastasis after 10 months, 1 developed liver metastasis after 20 months, and 1 developed PDAC in the remnant pancreas after 24 months. CONCLUSION: IICP seems to be a safe and useful method for detection of early stage PDAC concomitant with IPMN that cannot be detected by preoperative imaging or intraoperative examination.