Magnetic resonance (MR) imaging is a noninvasive means of providing images of the human body at high spatial resolution and contrast sensitivity. The contrast can be manipulated to depend on different properties of tissue water, enabling the study of a variety of biological processes. In some cases, endogenous or exogenous paramagnetic MR contrast agents are used to alter the MRI contrast by perturbing the tissue water environment. Recently, new MRI hardware has also enabled techniques having high temporal resolution. Using the unique contrast properties of MRI and the higher spatial/temporal resolution, noninvasive techniques can be devised to study neuronal activity, tissue perfusion, water mobility (diffusion), and neuronal fiber pathways in the human brain. The goals of Dr. Conturo's research lab are to develop and apply MR imaging techniques for quantitative imaging of cerebral perfusion, brain function, water diffusion, and neuronal fiber pathways. These techniques utilize the MR signal effects of exogenous bolus-injected contrast agents, endogenous hemoglobin, and microscopic water diffusion. Long-term goals are to apply these methodologies toward imaging and understanding tissue structure, function, and physiology in the brain and other organs in normal and abnormal conditions. The approaches that are used in this laboratory cover a broad range of areas, including MRI physics, MRI pulse sequence development, theoretical derivations, computer simulations, image-processing, computer graphics, custom contrast agent design and syntheois, phantom studies, animal models, human studies, clinical patient studies, and comparison with other imaging modalities.

https://link.springer.com/content/pdf/10.1007%2FBF02955327.pdf

Department of radiology

The determination of the incidence and prevalence of rare diseases is important for economists and health-care providers. Pseudomyxoma peritonei (PMP) is a rare, slow-growing abdominal cancer that represents a substantial burden on both patients and health-care systems. The incidence rate was previously approximated at 1–2 people per million per year; this incidence has never been challenged, and the prevalence has not been estimated. Epidemiological data from Norway and England were obtained and analysed to calculate a minimum incidence rate based on the number of patients having a first surgical intervention for PMP. A novel method was then used to determine a prevalence rate for PMP, incorporating incidence, death, and cure rates in a multi-year analysis that accounted for the increasing population of Europe over a 10-year period. An incidence rate of 3.2 people per million per year was calculated, with a corresponding estimated prevalence rate of 22 people per million per year. By this calculation, 11,736 people in Europe were estimated to be living with PMP in 2018. Incidence and prevalence are essential tools for assessment of the financial and human cost of a disease. For rare diseases, such as PMP, the lack of accurate registries presents a particular challenge in determining such health-related statistical parameters. Based on our calculations, a significant number of people are living with PMP in Europe, underlining the need for appropriate resource allocation to ensure that adequate health-care measures are provided.

/pdf/estimating-the-prevalence-of-pseudomyxoma-peritonei-in-4119h6tk8w.pdf

Estimating the Prevalence of Pseudomyxoma Peritonei in Europe Using a Novel Statistical Method

Epithelial appendiceal neoplasms are uncommon peritoneal malignancies causing a spectrum of disease including pseudomyxoma peritonei (PMP). The optimal management is cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC). Despite complete CRS (CCRS), recurrence develops in almost 45% of patients. No consensus exists for the optimal treatment of recurrent disease, with treatment strategies including repeat CRS, watch-and-wait, and palliative chemotherapy. This report aims to describe evolving management strategies for a large cohort with recurrence after CCRS. This retrospective study analyzed a prospective database of patients with recurrence after CCRS for appendiceal neoplasms from 1994 to 2017 who had long-term follow-up evaluation with tumor markers and computed tomography (CT). Overall, 430 (37.6%) of 1145 PMP patients experienced recurrence at a median of 19 months. Of these 430 patients 145 (33.7%) underwent repeat CRS, 119 (27.7%) had a watch-and-wait approach, and 119 (27.7%) had palliative chemotherapy. The patients with recurrence had a median overall survival (OS) of 39 months, a 3-year survival of 74.6%, a 5-year survival of 57.4%, and a 10-year survival of 36.5%. In the multivariate analysis, the patients who had recurrence within 1 year after primary CRS (hazard ratio [HR], 3.55), symptoms at recurrence (HR, 3.08), a high grade of disease or adenocarcinoma pathology (HR, 2.94), signet ring cells (HR, 1.91), extraperitoneal metastatic disease (HR, 1.71), or male gender (HR, 1.61) had worse OS. The OS was longer for the patients who had repeat CRS (HR, 0.41). The patients who underwent repeat CCRS had a 3-year OS of 87.5%, a 5-year OS of 78.1%, and a 10-year OS of 67.9%. Dilemmas persist around the optimal management of patients with recurrence after CRS and HIPEC for appendiceal tumors. Selected patients benefit from repeat CRS, particularly those with favorable tumor biology and focal disease.

Managing Recurrent Pseudomyxoma Peritonei in 430 Patients After Complete Cytoreduction and HIPEC: A Dilemma for Patients and Surgeons.

Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) provide long-term survival for low-grade pseudomyxoma peritonei (PMP) and multicystic peritoneal mesothelioma (MM). Feasibility of laparoscopic CRS-HIPEC has been reported for selected patients but data regarding long-term outcomes are missing to assess the oncological interest. This study aimed to report long-term outcomes for low-grade PMP and MM treated by laparoscopic approach. From a prospectively maintained CRS-HIPEC database, all patients who underwent laparoscopic CRS-HIPEC with curative intent were analyzed. Selection criteria for laparoscopic approach were low-grade PMP or MM, with pathological confirmation prior to CRS-HIPEC, ASA 2, age < 75 years, no extrap-eritoneal disease, Peritoneal Cancer Index (PCI) < 10, and a limited history of abdominal surgery. Between March 2009 and June 2017, 43 patients were scheduled for laparoscopic CRS and HIPEC. Laparoscopic CRS and HIPEC was completed (LSC) in 32 patients and 11 patients were converted to open surgery (CONV). Median age was 44.5 years (17.13–71.4) in the LSC group and 54.9 years (22.5–70.5) in the CONV group (p = 0.086). Median BMI was not different between groups, 21.2 and 23.9 for LSC and CONV groups, respectively (p = 0.267). There were 21 and 11 patients in the LSC group, and 8 and 3 in the CONV group, with PMP and MM, respectively (p = 0.794). Median PCI was 2.5 (0–9) and 7 (1–15) in the LSC and CONV groups, respectively (p = 0.004). There was no difference in the completeness of cytoreduction score (p = 0.256). After a median follow-up of 31.6 months (95% CI 19.3–36.4), 2 patients in the LSC group and 2 patients in the CONV group presented with peritoneal recurrence. For selected patients with low aggressive peritoneal disease, laparoscopic CRS-HIPEC provides interesting long-term outcomes.

Long-term results of laparoscopic cytoreductive surgery and HIPEC for the curative treatment of low-grade pseudomyxoma peritonei and multicystic mesothelioma.

Cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) is a major operation frequently necessitating red blood cell transfusion. Using multi-institutional data from the U.S. HIPEC Collaborative, this study sought to determine the association of perioperative allogenic blood transfusion (PABT) with perioperative outcomes after CRS/HIPEC. This retrospective cohort study analyzed patients who underwent CRS/HIPEC for peritoneal surface malignancy between 2000 and 2017. Propensity score-matching was performed to mitigate bias. Univariate analysis was used to compare demographic, preoperative, intraoperative, and postoperative variables. Factors independently associated with PABT were identified using multivariate analysis. The inclusion criteria were met by 1717 patients, 510 (29.7%) of whom required PABT. The mean Peritoneal Cancer Index (PCI) of our cohort was 14.8 ± 9.3. Propensity score-matching showed an independent association between PABT and postoperative risk of pleural effusion, hemorrhage, pulmonary embolism, enteric fistula formation, Clavien-Dindo grades 3 and 4 morbidity, longer hospital stay, and reoperation (all P < 0.05 in the multivariate analysis). Compared with the patients who received 1 to 5 red blood cell (RBC) units, the patients who received more than 5 units had a greater risk of renal impairment, a longer intensive care unit (ICU) stay, and more postoperative infections. Finally, PABT was an independent predictor of worse survival for patients with appendiceal and colorectal primaries. Even low levels of PABT for patients undergoing CRS/HIPEC are independently associated with a greater risk of infectious and non-infectious postoperative complications, and this risk is increased for patients receiving more than 5 RBC units. Worse survival was independently predicted by PABT for patients with peritoneal carcinomatosis of an appendiceal or colorectal origin.

Impact of Perioperative Blood Transfusions on Outcomes After Hyperthermic Intraperitoneal Chemotherapy: A Propensity-Matched Analysis

Background Pseudomyxoma peritonei (PMP) is a rare clinical condition characterized by mucinous ascites, typically related to appendiceal or ovarian tumours. Current standard treatment involves cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC), but recurrences occur in 20-30 per cent of patients. The aim of this study was to define the timing and patterns of recurrence to provide a basis for modifying follow-up of these patients. Methods This observational study examined a prospectively developed multicentre national database (RENAPE working group) to identify patients with recurrence after optimal CRS and HIPEC for PMP. Postoperative complications, long-term outcomes and potential prognostic factors were evaluated. Results Of 1411 patients with proven PMP, 948 were identified who had undergone curative CRS and HIPEC. Among these patients, 229 first recurrences (24·2 per cent) were identified: 196 (20·7 per cent) occurred within the first 5 years (early recurrence) and 30 (3·2 per cent) occurred between 5 and 10 years. Three patients developed a first recurrence more than 10 years after the original treatment. The mean(s.d.) time to first recurrence was 2·36(2·21) years. Preoperative chemotherapy and high-grade pathology were significant factors for early recurrence. Overall survival for the entire group was 77·9 and 63·1 per cent at 5 and 10 years respectively. The principal site of recurrence was the peritoneum. Conclusion Recurrence of PMP was rare after 5 years and exceptional after 10 years.

https://bjssjournals.onlinelibrary.wiley.com/doi/pdf/10.1002/bjs5.97

F Dumont

Papers

Recurrence of pseudomyxoma peritonei after cytoreductive surgery and hyperthermic intraperitoneal chemotherapy.