Diagnostic Accuracy of Quantitative Micro-Elastography for Margin Assessment in Breast-Conserving Surgery.

Inadequate margins in breast-conserving surgery (BCS) are associated with an increased likelihood of local recurrence of breast cancer. Currently, approximately 20% of BCS patients require repeat surgery due to inadequate margins at the initial operation. Implementation of an accurate, intraoperative margin assessment tool may reduce this re-excision rate. This study determined, for the first time, the diagnostic accuracy of quantitative micro-elastography (QME), an optical coherence tomography (OCT)-based elastography technique that produces images of tissue microscale elasticity, for detecting tumor within 1 mm of the margins of BCS specimens. Simultaneous OCT and QME were performed on the margins of intact, freshly excised specimens from 83 patients undergoing BCS and on dissected specimens from 7 patients undergoing mastectomy. The resulting three-dimensional images (45 × 45 × 1 mm) were coregistered with postoperative histology to determine tissue types present in each scan. Data from 12 BCS patients and the 7 mastectomy patients served to build a set of images for reader training. One hundred and fifty-four subimages (10 × 10 × 1 mm) from the remaining 71 BCS patients were included in a blinded reader study, which resulted in 69.0% sensitivity and 79.0% specificity using OCT images, versus 92.9% sensitivity and 96.4% specificity using elasticity images. The quantitative nature of QME also facilitated development of an automated reader, which resulted in 100.0% sensitivity and 97.7% specificity. These results demonstrate high accuracy of QME for detecting tumor within 1 mm of the margin and the potential for this technique to improve outcomes in BCS. SIGNIFICANCE: An optical imaging technology probes breast tissue elasticity to provide accurate assessment of tumor margin involvement in breast-conserving surgery.

Preoperative Radiographic Assessment Predicts Incomplete Cytoreduction in Patients with Low Grade Mucinous Adenocarcinoma of the Appendix.

BACKGROUND: Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) for patients with low-grade mucinous adenocarcinoma (LGMA) is most effective when complete cytoreduction is achieved. We externally validated two radiographic scoring systems to predict resectability and assessed radiographic response to systemic chemotherapy (SCT). METHODS: Patients with LGMA who received preoperative SCT followed by CRS/HIPEC from 2013 to 2016 were identified. CT scans were graded by six physicians using the simplified radiologic score (SRS) and simplified preoperative assessment of appendiceal tumor (SPAAT) systems. Positive and negative predictive values (PPV, NPV) were calculated by comparing to completeness of cytoreduction. Inter-rater agreement was assessed using the intraclass correlation coefficient (ICC). RESULTS: Twenty-four patients had preoperative SCT followed by CRS/HIPEC. Thirteen patients underwent incomplete CRS and 11 patients complete CRS. Scoring of the preoperative CT had a PPV of complete cytoreduction of 75% and 66.7% for SRS and SPAAT, respectively. NPV was 83.4% and 88.9% for SRS and SPAAT, respectively. ICC for the preoperative SRS and SPAAT score was 0.826 (95% confidence interval [CI]: 0.720-0.910] and 0.788 [0.667-0.888). Comparison of CT scans before and after SCT recorded an increase in calculated scores in 45.8% (SRS) and 50% (SPAAT) of patients. CONCLUSIONS: External validation of two radiographic scoring systems to predict complete cytoreduction showed that inter-rater agreement for both systems was good. Both scoring systems predicted incomplete cytoreduction. Applying a systematic approach to preoperative imaging review is recommended to improve treatment selection by minimizing morbidity associated with incomplete CRS and help to set patient expectations.

Quantitative MRI assessment of mucinous rectal adenocarcinoma to predict tumour response after neoadjuvant therapy.

AIM: To evaluate the association between volume ratio of the mucus pool and tumour response to neoadjuvant therapy in patients with mucinous rectal adenocarcinoma (MC). MATERIALS AND METHODS: The volume of the mucus pool and whole tumour on pre-therapeutic T2-weighted magnetic resonance imaging (MRI) of 79 patients was measured using semi-automated software. Mucus pool volume, whole tumour volume, and volume ratio of the mucus pool were compared to tumour response and tumour and lymph node downstaging after neoadjuvant therapy using receiver operating characteristic curve (ROC) and multivariate logistic regression analysis. RESULTS: After preoperative neoadjuvant therapy of rectal MC, the rate of pathological complete response, tumour downstaging, tumour response, and lymph node downstaging were 9%, 48%, 39% and 58%, respectively. Tumour downstaging more frequently occurred in patients with a mucus pool volume ratio of at least 68.3% (area under the ROC curve [AUC], 0.793 with 95% confidence interval [CI]: 0.693-0.893), and at least 62.1% for identifying those with a higher tumour response with an AUC of 0.739 (95% CI: 0.630-0.847). CONCLUSION: A higher volume ratio of mucus pool in patients with MC may be related to more tumour downstaging and therapy response, and therefore, could serve as an independent imaging biomarker for predicting tumour response to neoadjuvant therapy.

Are pancreatic IPMN volumes measured on MRI images more reproducible than diameters? An assessment in a large single-institution cohort.

OBJECTIVES: To assess reproducibility of volume and diameter measurement of intraductal papillary mucinous neoplasms (IPMNs) on MRI images. METHODS: Three readers measured the diameters and volumes of 164 IPMNs on axial T2-weighted images and coronal thin-slice navigator heavily T2-weighted images using manual and semiautomatic techniques. Interobserver reproducibility and variability were assessed. RESULTS: Interobserver intraclass correlation coefficients (ICCs) for the largest diameter measured using manual and semiautomatic techniques were 0.979 and 0.909 in the axial plane, and 0.969 and 0.961 in the coronal plane, respectively. Interobserver ICCs for the volume measurements were 0.973 and 0.970 in axial and coronal planes, respectively. The highest intraobserver reproducibility was noted for coronal manual measurements (ICC 0.981) followed by axial manual measurements (ICC 0.969). For the diameter measurements, Bland-Altman analysis revealed the lowest interobserver variability for manual axial measurements with an average range of 95% limits of agreement (LOA) of 0.68 cm. Axial and coronal volume measurements showed similar 95% LOA ranges (8.9 cm3 and 9.4 cm3, respectively). CONCLUSIONS: Volume and diameter measurements on axial and coronal images show good interobserver and intraobserver reproducibility. The single largest diameter measured manually on axial images showed the highest reproducibility and lowest variability. The 95% LOA may help define reproducible size changes in these lesions using measurements from different readers. KEY POINTS: • MRI measurements by different radiologists can be used for IPMN follow-up. • Both diameter and volume measurements demonstrate excellent interobserver and intraobserver reproducibility. • Manual axial measurements show the highest interobserver reproducibility in determining size. • Axial and coronal volume measurements show similar limits of agreement. • Manual axial measurements show the lowest variability in agreement range.

Diagnostic Usefulness of Combination of Diffusion-weighted Imaging and T2WI, Including Apparent Diffusion Coefficient in Breast Lesions: Assessment of Histologic Grade.

PURPOSE: This study aimed to compare the diagnostic values of a combination of diffusion-weighted imaging and T2-weighted imaging (DWI-T2WI) with dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI), and to evaluate the correlation of DWI with the histologic grade in breast cancer. MATERIALS AND METHODS: This study evaluated a total of 169 breast lesions from 136 patients who underwent both DCE-MRI and DWI (b value, 1000s/mm2). Morphologic and kinetic analyses for DCE-MRI were classified according to the Breast Imaging-Reporting and Data System. For the DWI-T2WI set, a DWI-T2WI score for lesion characterization that compared signal intensity of DWI and T2WI (benign: DWI-T2WI score of 1, 2; malignant: DWI-T2WI score of 3, 4, 5) was used. The diagnostic values of DCE-MRI, DWI-T2WI set, and combined assessment of DCE and DWI-T2WI were calculated. RESULTS: Of 169 breast lesions, 48 were benign and 121 were malignant (89 invasive ductal carcinoma, 24 ductal carcinoma in situ, 4 invasive lobular carcinoma, 4 mucinous carcinoma). The mean apparent diffusion coefficient (ADC) of invasive ductal carcinoma (0.92 ± 0.19 × 10-3 mm2/s) and ductal carcinoma in situ (1.11 ± 0.13 × 10-3 mm2/s) was significantly lower than the value seen in benign lesions (1.36 ± 0.22 × 10-3 mm2/s). The specificity, positive predictive value (PPV), and accuracy of DWI-T2WI set and combined assessment of DCE and DWI-T2WI (specificity, 87.5% and 91.7%; PPV, 94.3% and 96.2%; accuracy, Az = 0.876 and 0.922) were significantly higher than those of the DCE-MRI (specificity, 45.8%; PPV, 81.7%; accuracy, Az = 0.854; P < .05). A low ADC value and the presence of rim enhancement were associated with a higher histologic grade cancer (P < .05). CONCLUSION: Combining DWI, T2WI, and ADC values provides increased accuracy for differentiation between benign and malignant lesions, compared with DCE-MRI. A lower ADC value was associated with a higher histologic grade cancer.

Uptodate in the assessment and management of intraductal papillary mucinous neoplasms of the pancreas.

Intraductal Papillary Mucinous Neoplasms (IPMNs) are the most common cystic tumors of the pancreas and are considered premalignant lesions. IPMNs are characterized by the papillary growth of the ductal epithelium with rich mucin production, which is responsible for cystic segmental or diffuse dilatation of the main pancreatic duct (MPD) and/or its branches. According to the different involvement of pancreatic duct system, IPMNs are divided into main duct type (MD-IPMN), branch duct type (BD-IPMN), and mixed type (MT-IPMN). IPMNs may be incidentally discovered in asymptomatic patients, particularly in those with BD-IPMNs, when imaging studies are performed for unrelated indications. The increase in their frequency may reflect the combined effects of new diagnostic techniques, the improvement of radiologic exams and progress in the recognition of the pathology. MD-IPMNs present a higher risk of malignant progression than BD-IPMNs; as a consequence, all the guidelines strictly suggest the need of surgery for MD- and MT- IPMNs with MPD > 10 mm, while the management of BD-IPMNs is still controversial and depends on several cysts and patients features. The choice between non-operative and surgical management depends on the distinction between benign and invasive IPMN forms, assessment of malignancy risk, patient's wellness and its preferences. This manuscript revises the different guidelines for the management of IPMNs that have been published in different world countries: the international (Sendai 2006 and Fukuoka 2012), the 2013 European, the 2014 Italian, and finally the 2015 American guidelines. In summary, this review will integrate the recent insights in the combination of diagnostic techniques, such as Magnetic Resonance Imaging (MRI) and endoscopic ultrasound (EUS), pathology classification, and management of IPMNs.

Rectal Mucinous Adenocarcinoma: MR Imaging Assessment of Response to Concurrent Chemotherapy and Radiation Therapy-A Hypothesis-generating Study.

Purpose To develop a system for assessment of tumor regression grade (TRG) with magnetic resonance (MR) imaging that is applicable to rectal mucinous adenocarcinoma (RMAC) and to obtain a preliminary evaluation of the association of MR imaging assessment of TRG with response to preoperative concurrent chemotherapy and radiation therapy (CCRT). Materials and Methods This retrospective study was approved by the institutional review board, and informed consent was waived. Pre- and post-CCRT MR images of 59 patients with RMAC (median age, 59 years; range, 29-80 years; 42 men [median age, 59 years; range, 36-80 years] and 17 women [median age, 57 years; range, 29-79 years]) who underwent CCRT and subsequent elective resection from July 2005 to June 2015 were analyzed. Two experienced gastrointestinal radiologists independently analyzed imaging parameters such as T stage, mesorectal fascia status, extramural vascular invasion status, and TRG by using modified criteria developed for assessment of RMAC. Interobserver variability was calculated with weighted κ analysis, and disagreement was settled in consensus. MR imaging TRG results were compared with those from pathologic TRG analysis (Mandard grade). Logistic regression analyses were performed to evaluate associations between imaging parameters and pathologic TRG. Results There was moderate to substantial agreement for imaging parameters (post-CCRT T stage-weighted κ, 0.7134; post-CCRT mesorectal fascia status, 0.618; TRG, 0.5023). Modified MR imaging TRG results were significantly associated with pathologic responsiveness (responsive group, Mandard grade 1 or 2; nonresponsive group, Mandard grades 3-5; P = .023). Results of univariate and multivariate logistic regression analyses indicated that MR imaging TRG was the only factor significantly associated with CCRT responsiveness (univariate analysis, P = .023; multivariate analysis, P = .0261). Conclusion The modified MR imaging assessment of TRG was associated with treatment response to CCRT in patients with RMAC. © RSNA, 2017 Online supplemental material is available for this article.

Computed Tomography Follow-Up Assessment of Patients with Low-Grade Appendiceal Mucinous Neoplasms: Evaluation of Risk for Pseudomyxoma Peritonei.

BACKGROUND: Low-grade appendiceal mucinous neoplasms are rare. Both classification and management vary. This study aimed to follow up on patients with a diagnosis of LAMN after primary surgery with computer tomography (CT) scans to examine the risk for the development of pseudomyxoma peritonei (PMP). METHODS: This population-based prospective study investigated patients who underwent appendectomy between 2007 and 2013 and had histology results demonstrating the presence of LAMN. The patients were followed up with a CT scan every 6 months for 2 years, until December 2015. RESULTS: The study investigated 41 patients (20 females) with a median age of 65 years (range 20-87 years). The entire appendix was processed and examined, with results showing that 12 were perforated, and 3 had a positive margin. Extra-appendiceal mucin on the surface of the appendix was found in ten cases, and in two cases, extra-mucinous epithelial cells were detected. During a median follow-up period of 5.1 years (range 2-8.6 years), none of the patients experienced the development of PMP. CONCLUSIONS: These data suggest that for patients with LAMN confined to the appendix, involvement of the appendectomy margin or perforation with mucin locally, even with epithelial cells, did not predict the development of PMP, and a conservative approach seems justified. No reoperation was needed, and regular follow-up evaluation with CT scans was sufficient.

External Validation of the Simplified Preoperative Assessment for Low-Grade Mucinous Adenocarcinoma of the Appendix.

BACKGROUND: MD Anderson Cancer Center developed a computed tomography (CT)-based preoperative assessment tool simplified preoperative assessment for appendix tumor (SPAAT) for predicting incomplete cytoreduction (IC) in low-grade mucinous adenocarcinoma (LGMA) of the appendix, based on preoperative CT scans. This study independently evaluates the tool's performance. METHODS: Seventy-six preoperative CT scans of LGMA patients were evaluated by two surgeons unfamiliar with the patients' medical history. Scores were assigned based on SPAAT criteria, with a SPAAT ≥3 predictive of IC. Binary regression analyses and area under the receiver operating characteristic (AUROC) curve analyses were performed. Patients with splenic resection were excluded due to the structure of the SPAAT assessment tool. RESULTS: Seventy-six LGMA patients underwent attempted cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS/HIPEC). Of 68 patients, 58 had complete cytoreduction and 10 had IC; 8 patients were ineligible due to prior splenectomy. The mean SPAAT score was 0.8, with six patients having SPAAT scores ≥3. SPAAT scores ≥3 were predictive of IC, with a hazard ratio (HR) of 19 (95% confidence interval 2.8-124.1) (p = 0.002). Sensitivity, specificity, positive predictive value (PPV), and negative predictive value were 40, 97, 50, and 90%, respectively. A SPAAT score ≥3 was not associated with worse survival prognosis. Median follow-up was 2.4 years and AUROC curve was 71%. SPAAT components with respective HR and p-values were foreshortening of the bowel mesentery (29.5; p = 0.004), and scalloping of the pancreas (9; p = 0.008), spleen (4.3; p = 0.04), portal vein (3.1; p = 0.4), and liver (2.1; p = 0.3). CONCLUSION: A SPAAT score ≥3 predicted IC based on a binary regression model. The clinical value of this score is controversial due to low sensitivity and PPV.

Assessment of a Revised Management Strategy for Patients With Intraductal Papillary Mucinous Neoplasms Involving the Main Pancreatic Duct.

Importance: According to the 2012 International Consensus Guidelines, the diagnostic criterion of intraductal papillary mucinous neoplasms (IPMNs) involving the main duct (MD IPMNs) or the main and branch ducts (mixed IPMNs) of the pancreatic system is a main pancreatic duct (MPD) diameter of 5.0 mm or greater on computed tomography (CT) or magnetic resonance imaging (MRI). However, surgical resection is recommended for patients with an MPD diameter of 10.0 mm or greater, which is characterized as a high-risk stigma. An MPD diameter of 5.0 to 9.0 mm is not an indication for immediate resection. Objectives: To determine an appropriate cutoff (ie, one with high sensitivity and negative predictive value) of the MPD diameter on CT or MRI as a prognostic factor for malignant disease and to propose a new management algorithm for patients with MD or mixed IPMNs. Design, Setting, and Participants: This retrospective cohort study included 103 patients who underwent surgical resection for a preoperative diagnosis of MD or mixed IPMN and in whom IPMN was confirmed by surgical pathologic findings at a single institution from July 1, 1996, to December 31, 2015. Main Outcomes and Measures: Malignant disease was defined as high-grade dysplasia or invasive adenocarcinoma on results of surgical pathologic evaluation. An appropriate MPD diameter on preoperative CT or MRI to predict malignant disease was determined using a receiver operating characteristic curve analysis. The prognostic value of the new management algorithm that incorporated the new MPD diameter cutoff was evaluated. Results: Among the 103 patients undergoing resection for an MD or mixed IPMN (59 men [57.3%]; 44 women [42.7%]; median [range] age, 71 [48-86] years), 64 (62.1%) had malignant disease. Diagnostic accuracy for malignant neoplasms was highest at an MPD diameter cutoff of 7.2 mm (area under the receiver operating characteristic curve, 0.70; 95% CI, 0.59-0.81). An MPD diameter of 7.2 mm or greater was also an independent prognostic factor for malignant neoplasms (odds ratio, 12.76; 95% CI, 2.43-66.88; P = .003) on logistic regression analysis after controlling for preoperative variables. The new management algorithm, which included an MPD diameter of 7.2 mm or greater as one of the high-risk stigmata, had a higher sensitivity (100%), negative predictive value (100%), and accuracy (66%) for malignant disease than the 2012 version of the International Consensus Guidelines (95%, 57%, and 63%, respectively). Conclusions and Relevance: In this single-center, retrospective analysis, an MPD diameter of 7.2 mm was identified as an optimal cutoff for a prognostic factor for malignant disease in MD or mixed IPMN. These data support lowering the accepted criteria for MPD diameter when selecting patients for resection vs surveillance so as not to overlook cancer in IPMN.

Assessment of Malignant Potential in Intraductal Papillary Mucinous Neoplasms of the Pancreas: Comparison between Multidetector CT and MR Imaging with MR Cholangiopancreatography.

PURPOSE: To compare the diagnostic performance of multidetector computed tomography (CT) and magnetic resonance (MR) imaging with MR cholangiopancreatography (MRCP) in identifying the malignant potential of pancreatic intraductal papillary neoplasms (IPMNs) and evaluate their intermodality agreement. MATERIALS AND METHODS: Institutional review board approval was obtained, and the requirement for informed consent was waived for this retrospective study. In 129 patients with pathologically proved pancreatic IPMNs, three reviewers independently evaluated their preoperative CT and MR imaging with MRCP findings. Intermodality agreement between multidetector CT and MR imaging with MRCP, as well as interobserver agreement of each imaging modality, for depicting high-risk stigmata and worrisome features were assessed. Diagnostic values of other signs of overt malignancy, including the presence of a parenchymal mass and local-regional extension, were analyzed. Diagnostic performance and intermodality agreement were assessed by using receiver operating characteristics (ROC) curve analysis and weighted κ statistics. RESULTS: Overall, multidetector CT and MR imaging with MRCP were similar in their ability to depict signs suspicious or indicative of malignancy in patients with IPMN (area under the ROC curve [AUC] = 0.82 for both), with good intermodality agreement (κ = 0.75) and moderate interobserver agreement (κ = 0.47-0.59) when high-grade dysplasia was used as the cutoff for malignancy. When parenchymal masses and local-regional extensions were also considered as overt signs of malignancy, the ability to identify invasive IPMNs significantly increased (AUC = 0.87 for CT and AUC = 0.88 for MR imaging), with high sensitivity (94.3%), while maintaining specificity (69.1%). CONCLUSION: The diagnostic performance of multidetector CT and MR imaging with MRCP for identifying the malignant potential of pancreatic IPMNs was similar and showed good intermodality agreement, suggesting that follow-up with either modality may be used.

A Simplified Preoperative Assessment Predicts Complete Cytoreduction and Outcomes in Patients with Low-Grade Mucinous Adenocarcinoma of the Appendix.

BACKGROUND: Complete cytoreduction with hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) has been shown to improve survival in patients with low-grade mucinous adenocarcinoma (LGMA). However, incomplete cytoreduction exposes patients to significant morbidity without a similar survival benefit. Preoperative assessment of the ability to achieve CRS is therefore a critical step in selecting patients for CRS/HIPEC. OBJECTIVE: The aim of this study was to develop and validate a preoperative scoring system to accurately predict the ability to achieve complete cytoreduction in patients with LGMA of the appendix. METHODS: A simplified preoperative assessment for appendix tumor (SPAAT) score was developed based on computed tomography scan findings thought to predict incomplete cytoreduction. We applied the SPAAT score to patients with LGMA to determine the ability of the score to predict complete cytoreduction. This scoring system was then applied to a separate cohort of patients from a different institution. Sensitivity and specificity were determined for the SPAAT score. Survival was calculated and correlated with the SPAAT score and the completeness of cytoreduction score. RESULTS: A SPAAT score of <3 is a significant predictor of complete cytoreduction in the derivation cohort. In the validation cohort, 40 of 42 patients with a SPAAT score <3 achieved a complete cytoreduction, for a positive predictive value of 95.2 % and a negative predictive value of 100 %. Additionally, the SPAAT score was a significant predictor of disease-free survival. CONCLUSIONS: The SPAAT score is a useful tool in the preoperative assessment of patients with LGMA who are under consideration for cytoreductive surgery. Prospective analysis of this scoring system is warranted to appropriately select patients who will benefit from CRS/HIPEC.

Risk for malignant and borderline ovarian neoplasms following basic preoperative evaluation by ultrasonography, ca125 level and age.

OBJECTIVE: To verify the basic preoperative evaluation in the discrimination between benign and malignant adnexal masses in our clinical practice. MATERIALS AND METHODS: Data were collected on the records of 636 women with adnexal masses who had undergone surgery either by open or endoscopic approaches. Those with obvious signs of malignancy, any history of cancer, emergency surgeries without basic evaluation were excluded. The preoperative features by age, ultrasound and serum Ca125 level were compared with final histopathological diagnosis at the four departments of the institution. These are the general gynecology (Group 1: exploratory laparotomy), the gynecologic endoscopy (Group 2: laparoscopy and adnexectomy), the gynecological oncology (Group 3: staging laparotomy) and the gynecologic endocrinology and infertility (Group 4: laparoscopy and cystectomy). RESULTS: There were simple and complex cyst rates of 22.3% and 77.2%, respectively. There were 86.3% benign, 4.1% (n:20) borderline ovarian tumor (BOT) and 6.4% (n:48) malignant lesions. There were 3 BOT and 9 ovarian cancers in Group 1 and one BOT and two ovarian cancer in the Group 2. During the surgery, 15 BOT (75%) and 37 ovarian cancer (77%) were detected in the Group 3, only one BOT was encountered in the Group 4. The risk of rate of unsuspected borderline or focally invasive ovarian cancer significantly increased by age, size, complex morphology and Ca125 (95% CI, OR=2.72, OR=6.60, OR=6.66 and OR=4.69, respectively). CONCLUSIONS: Basic preoperative evaluation by comprehensive ultrasound imaging combined with age and Ca125 level has proved highly accurate for prediction of unexpected malignancies. Neither novel markers nor new imaging techniques provide better information that allow clinicians to assess the feasibility of the planned surgery; consequently, the risk of inadvertent cyst rupture during laparoscopy may be significantly decreased in selected cases.

CT findings of intraductal papillary neoplasm of the bile duct: assessment with multiphase contrast-enhanced examination using multi-detector CT.

AIM: To evaluate multi-detector computed tomography (MDCT) findings of intraductal papillary neoplasm of the bile duct (IPNB), a neoplasm that is considered to be the biliary counterpart of pancreatic intraductal papillary mucinous neoplasm. MATERIALS AND METHODS: Two radiologists retrospectively evaluated multiphase contrast-enhanced CT images with 0.5 or 1mm collimation in 37 consecutive patients with resected IPNB diagnosed by a single pathologist. The CT findings were correlated with the pathological findings concerning invasion of the surrounding organs and vessels. RESULTS: All patients showed bile duct dilatation. An intraductal mass was detected in 36 patients and the following findings were observed: extensive infiltration along the bile duct more than 20mm (n=32), compared with normal hepatic parenchyma, isodense or hyperdense during the late arterial phase (n=31), not hyperdense during the portal-venous and delayed phases (n=36), and intense enhancement rim at the base of the mass during the portal-venous or delayed phase (n=27). Parenchymal invasion of the surrounding organs was seen in eight of 16 tumours showing irregular or bulging margins. Vascular invasion was false positive in four of eight tumours. CONCLUSIONS: IPNB exhibits relatively characteristic findings with multiphase contrast-enhanced examination using MDCT. A tendency to overestimate invasion of the surrounding organs and vessels was seen.

Intraductal papillary mucinous neoplasm of the pancreas: assessment of the likelihood of invasiveness with multisection CT.

PURPOSE: To evaluate the capabilities of multisection computed tomography (CT) in determining the likelihood of invasiveness of intraductal papillary mucinous neoplasm (IPMN). MATERIALS AND METHODS: The institutional review board approved this research and waived informed consent from the patients. Two radiologists blinded to the pathologic assessment of malignancy or parenchymal invasion of IPMN retrospectively evaluated CT images of 61 consecutive surgically resected tumors (26 adenomas, 15 noninvasive carcinomas, and 20 invasive carcinomas) in patients who underwent multiphase contrast material-enhanced CT with 0.5- or 1-mm collimation. The findings were statistically analyzed by using univariate and multivariate analyses, with the optimal cutoff levels of each continuous parameter determined by generating receiver operating characteristic curves. RESULTS: The following findings showed significant differences among the three groups: maximum diameter of the main pancreatic duct (MPD), size (length of major axis) of the largest mural nodule in the MPD or in any associated cystic lesion, abnormal attenuating area in the surrounding parenchyma, calcification in the lesion, protrusion of the MPD into the ampulla of Vater, and bile duct dilatation. An MPD diameter of 6 mm or larger, a mural nodule of 3 mm or larger, and an abnormal attenuating area were independently predictive of malignancy. A mural nodule of 6.3 mm or larger in the MPD and an abnormal attenuating area were independently predictive of parenchymal invasion. According to these criteria, the sensitivity, specificity, and accuracy for identifying malignancy were 83%, 81%, and 82% and for identifying parenchymal invasion were 90%, 88%, and 89%, respectively. CONCLUSION: Multisection CT is useful for distinguishing among adenoma, noninvasive carcinoma, and invasive carcinoma in patients with IPMN.

Usefulness of FDG-PET scan in the assessment of suspected metastatic or recurrent adenocarcinoma of the colon and rectum.

PURPOSE: The purpose of this study was to evaluate the clinical efficacy of positron emission tomography with 2-[18F] fluoro-2-deoxy-D-glucose compared with computed tomography plus other conventional diagnostic studies in patients suspected of having metastatic or recurrent colorectal adenocarcinoma. METHODS: The records of 105 patients who underwent 101 computed tomography and 109 2-[18F] fluoro-2-deoxy-D-glucose positron emission tomography scans for suspected metastatic or recurrent colorectal adenocarcinoma were reviewed. Clinical correlation was confirmed at time of operation, histopathologically, or by clinical course. RESULTS: The overall sensitivity and specificity of 2-[18F] fluoro-2-deoxy-D-glucose positron emission tomography in detection of clinically relevant tumor were higher (87 and 68 percent) than for computed tomography plus other conventional diagnostic studies (66 and 59 percent). The sensitivity of 2-[18F] fluoro-2-deoxy-D-glucose positron emission tomography in detecting mucinous cancer was lower (58 percent; n = 16) than for nonmucinous cancer (92 percent; n = 93). The sensitivity of 2-[18F] fluoro-2-deoxy-D-glucose positron emission tomography in detecting locoregional recurrence (n = 70) was higher than for computed tomography plus colonoscopy (90 vs. 71 percent, respectively). The sensitivity of 2-[18F] fluoro-2-deoxy-D-glucose positron emission tomography in detecting hepatic metastasis (n = 101) was higher than for computed tomography (89 vs. 71 percent). The sensitivity of 2-[18F] fluoro-2-deoxy-D-glucose positron emission tomography in detecting extrahepatic metastases exclusive of locoregional recurrence (n = 101) was higher than for computed tomography plus other conventional diagnostic studies (94 vs. 67 percent). 2-[18F] fluoro-2-deoxy-D-glucose positron emission tomography altered clinical management in a beneficial manner in 26 percent of cases (26/101) when compared with evaluation by computed tomography plus other conventional diagnostic studies. CONCLUSION: 2-[18F] fluoro-2-deoxy-D-glucose positron emission tomography is more sensitive than computed tomography for the detection of metastatic or recurrent colorectal cancer and may improve clinical management in one-quarter of cases. However, 2-[18F] fluoro-2-deoxy-D-glucose positron emission tomography is not as sensitive in detecting mucinous adenocarcinoma, possibly because of the relative hypocellularity of these tumors.

Prospective assessment of primary rectal cancer response to preoperative radiation and chemotherapy using 18-fluorodeoxyglucose positron emission tomography.

PURPOSE: The purpose of this prospective study was to determine the ability of fluorine-18 fluorodeoxyglucose positron emission tomography to assess extent of pathologically confirmed rectal cancer response to preoperative radiation and 5-fluorouracil-based chemotherapy. METHODS: Patients with primary rectal cancer deemed eligible for preoperative radiation and 5-fluorouracil-based chemotherapy because of a clinically bulky or tethered tumor or endorectal ultrasound evidence of T3 and/or N1 were prospectively enrolled. Positron emission tomography and CT scans were obtained before preoperative radiation and 5-fluorouracil-based chemotherapy (5,040 cGy to the pelvis and 2 cycles of bolus 5-fluorouracil with leucovorin) and repeated four to five weeks after completion of radiation and 5-fluorouracil-based chemotherapy. In addition to routine pathologic staging, detailed assessment of rectal cancer response to preoperative radiation and 5-fluorouracil-based chemotherapy was performed independently by two pathologists. Positron emission tomography parameters studied included conventional measures such as standardized uptake value (average and maximum), positron emission tomography-derived tumor volume (size), and two novel parameters: visual response score and change in total lesion glycolysis. RESULTS: Of 21 patients enrolled, prospective data (pretreatment and posttreatment positron emission tomography, and complete pathologic assessment) were available on 15 patients. All 15 demonstrated pathologic response to preoperative radiation and 5-fluorouracil-based chemotherapy. This was confirmed in 100 percent of the cases by positron emission tomography compared with 78 percent (7/9) by CT. In addition, one positron emission tomography parameter (visual response score) accurately estimated the extent of pathologic response in 60 percent (9/15) of cases compared with 22 percent (2/9) of cases with CT. CONCLUSIONS: This pilot study demonstrates that fluorine-18 fluorodeoxyglucose positron emission tomography imaging adds incremental information to the preoperative assessment of patients with rectal cancer. However, further studies in a larger series of patients are needed to verify these findings and to determine the value of fluorine-18 fluorodeoxyglucose positron emission tomography in a preoperative strategy aimed at identifying patients suitable for sphincter-preserving rectal cancer surgery.

Internal mammary lymphoscintigraphy in the assessment of patients with ovarian carcinoma.

Radiocolloid internal mammary lymphoscintigraphy (IML) was evaluated in 364 patients with ovarian carcinoma to determine the frequency of abnormalities in post-operative patients, the association between the results of the lymphoscintigram and known clinical prognostic variables, and to establish whether IML yielded predictive information independent of these variables. Results of IML showed a correlation with established clinical prognostic features and yielded independent prognostic information. The sensitivity and specificity of IML in predicting relapse are 51% and 71% respectively, indicating that a single post-operative IML does not predict relapse or freedom from relapse with sufficient accuracy to make it a clinically useful test even though it provides an independent prediction of relapse.