Multi-institutional analysis of recurrence and survival after hepatectomy for fibrolamellar carcinoma.

BACKGROUND AND OBJECTIVES: Fibrolamellar carcinoma (FLC) presents in young, otherwise-healthy individuals. This study examined recurrence and survival characteristics after surgical resection for FLC by utilizing an international multi-institutional database. METHODS: Consecutive patients undergoing hepatectomy for FLC from six institutions (1993-2010) were reviewed retrospectively. Survival was studied with life tables and Cox regression models. RESULTS: Thirty-five patients (13 female, 37%) were included (median age: 32 years). R0 resection was achieved in all curative-intent operations (n = 30), and palliative operations were performed for five patients. Crude 30-day morbidity and mortality rates were 22% and 3%, respectively. For curative-intent surgery, overall and recurrence-free survivals at 5 years were 62% and 45%, respectively. In patients who achieved a 4-year disease-free interval after surgery, none subsequently developed recurrence. In multivariate models, presence of extrahepatic disease was the only factor that independently predicted overall (hazard ratio [HR]: 5.58, 95% confidence interval [CI]: 1.38-22.55, P = 0.016) and recurrence-free survival (HR: 5.64, 95% CI: 1.48-21.49, P = 0.011). CONCLUSIONS: Patients with surgically amenable FLC had encouraging long-term survival. Recurrence-free survival to 4 years suggested possible freedom from disease thereafter. Recurrent resectable disease was associated with an excellent prognosis, and repeat surgery should be strongly considered.

Recurrence after microwave ablation of liver malignancies: a single institution experience.

BACKGROUND: Microwave ablation (MWA) is increasingly used to achieve local control for liver tumours. This study sought to examine a monocentric experience with MWA, with a primary hypothesis that primary tumour histology was a significant predictor of early recurrence. METHODS: Retrospective single-institution review identified consecutive patients with liver tumours treated by MWA. Cox proportional hazards models assessed significance of prognostic variables. RESULTS: Seventy-two patients (43 female, 60%) underwent 83 MWA procedures for 157 tumours. Tumour histologies included hepatocellular cancer (10 operations), colorectal metastases (39), metastatic carcinoid (20) and other (14). The median tumour size was 2.0 cm. A concomitant liver resection was performed in 50 cases (60%). Crude peri-operative morbidity and mortality rates were 16% and 1%, respectively. The median follow-up was 16 months. Ablations were complete for 149 out of 157 tumours (95%). The median overall and recurrence-free survivals were 36 and 18 months, respectively. There was no difference in time to recurrence between the primary tumour types. In multivariable models, recurrence-free survival was independently associated with the use of neoadjuvant [hazard ratio (HR): 2.90, 95% confidence interval (CI): 1.09-7.76, P = 0.034] and adjuvant chemotherapy (HR: 0.36, 95% CI: 0.15-0.82, P = 0.016). CONCLUSIONS: MWA is a safe and feasible approach for local control of liver tumours. While chemotherapy administration was associated with time to recurrence after MWA, larger studies are needed to corroborate these findings.

Rapid size-controlled synthesis of dextran-coated, 64Cu-doped iron oxide nanoparticles.

Research into developing dual modality probes enabled for magnetic resonance imaging (MRI) and positron emission tomography (PET) has been on the rise recently due to the potential to combine the high resolution of MRI and the high sensitivity of PET. Current synthesis techniques for developing multimodal probes is largely hindered in part by prolonged reaction times during radioisotope incorporation--leading to a weakening of the radioactivity. Along with a time-efficient synthesis, the resulting products must fit within a critical size range (between 20 and 100 nm) to increase blood retention time. In this work, we describe a novel, rapid, microwave-based synthesis technique to grow dextran-coated iron oxide nanoparticles doped with copper (DIO/Cu). Traditional methods for coprecipitation of dextran-coated iron oxide nanoparticles require refluxing for 2 h and result in approximately 50 nm diameter particles. We demonstrate that microwave synthesis can produce 50 nm nanoparticles with 5 min of heating. We discuss the various parameters used in the microwave synthesis protocol to vary the size distribution of DIO/Cu and demonstrate the successful incorporation of (64)Cu into these particles with the aim of future use for dual-mode MR/PET imaging.

Comparison of iatrogenic splenectomy during open and laparoscopic colon resection.

Iatrogenic splenic injury requiring splenectomy is a well-recognized and potentially serious complication of colon resection. Iatrogenic splenectomy is associated with significant morbidity and mortality, including bleeding and the postsplenectomy sepsis syndrome. Our study aims to compare the incidence of iatrogenic splenectomy in laparoscopic colon resection with that of open colon resection over an 11-year-period at Mount Sinai. A retrospective chart review of all patients undergoing colon resection at Mount Sinai Medical Center during the last 11 years was performed to identify patient demographics, procedure, indication, and outcome. There was a significant difference (P=0.03) in the incidence of iatrogenic splenectomy during open colectomy (13/5477, 0.24%) versus laparoscopic colectomy (0/1911, 0%). All cases complicated by iatrogenic splenectomy involved splenic flexure mobilization. Laparoscopy has many recognized advantages over open procedures, including shorter recovery and length of stay. This retrospective review of our experience at Mount Sinai presents another potential benefit of the laparoscopic approach to colon resection.

Extensive genomic plasticity in Pseudomonas aeruginosa revealed by identification and distribution studies of novel genes among clinical isolates.

The distributed genome hypothesis (DGH) states that each strain within a bacterial species receives a unique distribution of genes from a population-based supragenome that is many times larger than the genome of any given strain. The observations that natural infecting populations are often polyclonal and that most chronic bacterial pathogens have highly developed mechanisms for horizontal gene transfer suggested the DGH and provided the means and the mechanisms to explain how chronic infections persist in the face of a mammalian host's adaptive defense mechanisms. Having previously established the validity of the DGH for obligate pathogens, we wished to evaluate its applicability to an opportunistic bacterial pathogen. This was accomplished by construction and analysis of a highly redundant pooled genomic library containing approximately 216,000 functional clones that was constructed from 12 low-passage clinical isolates of Pseudomonas aeruginosa, 6 otorrheic isolates and 6 from other body sites. Sequence analysis of 3,214 randomly picked clones (mean insert size, approximately 1.4 kb) from this library demonstrated that 348 (10.8%) of the clones were unique with respect to all genomic sequences of the P. aeruginosa prototype strain, PAO1. Hypothetical translations of the open reading frames within these unique sequences demonstrated protein homologies to a number of bacterial virulence factors and other proteins not previously identified in P. aeruginosa. PCR and reverse transcription-PCR-based assays were performed to analyze the distribution and expression patterns of a 70-open reading frame subset of these sequences among 11 of the clinical strains. These sequences were unevenly distributed among the clinical isolates, with nearly half (34/70) of the novel sequences being present in only one or two of the individual strains. Expression profiling revealed that a vast majority of these sequences are expressed, strongly suggesting they encode functional proteins.

Clerkship sharing on inpatient internal medicine rotations: an emerging clerkship model.

BACKGROUND: "Clerkship sharing" is the coexistence of students from 2 or more medical schools rotating on the same specialty at a single clerkship site. PURPOSE: Clerkship sharing was characterized by answering three related questions regarding the prevalence of clerkship sharing on internal medicine inpatient rotations, stakeholders views of the advantages and disadvantages of clerkship sharing, and the ways that clerkship sharing affects medical student outcomes at an institution. METHODS: In 2001, the Clerkship Directors in Internal Medicine (CDIM) surveyed its members; 1 section addressed clerkship sharing on inpatient rotations. In addition, the authors surveyed a convenience sample of teachers and learners at 41% of schools with clerkship sharing. Finally, using a 10-year database from one institution, we searched for differences in clerkship outcomes among students who rotated at clerkship sites with or without clerkship sharing. RESULTS: The overall clerkship director (CD) survey response rate was 78% (96/123); 22 of 96 (23%) of CDs reported having clerkship sharing on inpatient rotations. Advantages reported included a greater diversity of clinical exposure for students (77%) and a fostering of collegial relationships (73%). We also collected 79 teacher and 77 medical student surveys from 9 (41%) medical schools identified as having clerkship sharing. The majority of these teachers and learners believed that sharing improves teaching and the overall rotation quality. All surveyed groups were concerned that clerkship sharing affected the clarity of clerkship goals, objectives, and grading. However, clerkship outcomes from 1 institution demonstrated no effect of clerkship sharing on faculty ratings of students or student examination performance. CONCLUSIONS: Clerkship sharing appears to be an emerging clerkship model, and, although it may have inherent advantages that benefit student education, CDs should address challenges such as common goals and expectations for students and teachers.