Close distal margin is associated with locoregional rectal cancer recurrence: A multicenter study.

BACKGROUND AND OBJECTIVES: The importance of the radial margin for rectal cancer resection is well understood. However, surgeons have deemphasized the distal margin, accepting very close distal margins to perform sphincter-preserving surgery. We hypothesized that distal margins < 1 cm would be an independent risk factor for locoregional recurrence. The objective was to determine whether close distal margins are associated with increased locoregional recurrence risk. METHODS: This was a multi-institutional retrospective cohort study conducted at six academic medical centers including patients who received low anterior resection surgery for primary rectal cancer between 2007 and 2018. RESULTS: Of 556 low anterior resection patients, the rate of close distal margin was 12.8% (n = 71), and the locoregional recurrence rate was 5.0% (n = 28). The locoregional recurrence rate for close distal margin cases was 9.9% (n = 7) compared to 4.3% (n = 21) for distal margins ≥1.0 cm. In multivariable analysis, the only factor significantly associated with locoregional recurrence was close distal margin (adjusted odds ratio: 2.80, confidence interval: 1.08-7.25, p = 0.035). CONCLUSIONS: Rectal cancer patients with close distal margins (<1 cm) following low anterior resection had a significantly higher risk for locoregional recurrence. Therefore, the decision to perform low anterior resection with margins < 1 cm should be taken with caution.

Management and Outcomes of Pathologic Upstaging of Clinical Stage I Rectal Cancers: An Exploratory Analysis.

BACKGROUND: Preoperative staging of clinical stage I rectal cancer can fail to diagnose T3 or nodal disease. Adjuvant treatment of these upstaged patients remains controversial. OBJECTIVE: The objective was to identify predictors of clinical stage I rectal cancer upstaging and quantify rates of local and systemic recurrence. DESIGN: This was a retrospective cohort study. SETTINGS: The study was conducted using data from the United States Rectal Cancer Consortium, a registry of 1881 rectal cancer resections performed at 6 academic medical centers. PATIENTS: There were a total of 94 clinical stage I rectal cancer patients who underwent proctectomy without preoperative therapy. MAIN OUTCOME MEASURES: The primary measures were incidence of pathologic upstaging, recurrence (local and systemic), and overall survival. RESULTS: Among 94 clinical stage I patients who underwent proctectomy without preoperative therapy, 23 (24.5%) were upstaged by surgical pathology. There were 6 pT3N0 patients, 8 pT1-2N+ patients, and 9 pT3N+ patients. There were no significant differences in demographic or clinical characteristics between upstaged and nonupstaged patients. Of the 6 patients who were upstaged to T3N0 disease, none received adjuvant therapy and none developed recurrence. Of the 17 patients who were upstaged to N+ disease, 14 (82%) received adjuvant chemotherapy and 6 (35%) received adjuvant chemoradiation. None developed a local recurrence, but 4 (24%) developed systemic recurrence, and 2 (12%) died of disease over a mean of 36 months of follow-up. Among the 9 pT3N+ patients, the systemic recurrence rate was 33%, despite 8 of 9 patients receiving adjuvant fluorouracil, leucovorin, and oxaliplatin. LIMITATIONS: Small sample size hinders the ability to draw significant conclusions. CONCLUSIONS: One in 4 patients with stage I rectal cancer had unrecognized T3 or nodal disease found on operative pathology. Occult nodal disease was associated with worse outcomes, despite receiving adjuvant therapy. Systemic recurrence was more common than local recurrence. See Video Abstract at http://links.lww.com/DCR/B885 . MANEJO Y RESULTADOS DEL AUMENTO DEL ESTADIO PATOLGICO DE LOS CNCERES DE RECTO EN ESTADIO CLNICO I UN ANLISIS EXPLORATORIO: ANTECEDENTES:El estadiaje pre-operatorio del cáncer de recto en fase clínica I puede ser erróneo en el diagnóstico T3 o en la diseminación ganglionar. El tratamiento adyuvante de estos pacientes sobre-estadificados ​​sigue siendo controvertido.OBJETIVO:El identificar los factores predictivos en fase clínica I del cáncer de recto y cuantificar las tasas de recurrencia local y sistémica.DISEÑO:Estudio de cohortes retrospectivo.AJUSTE:El estudio se realizó utilizando los datos del Consorcio del Cáncer de Recto de los Estados Unidos, con un registro de 1.881 resecciones oncológicas rectales realizadas en seis centros médicos académicos.PACIENTES:Un total de 94 pacientes con cáncer de recto en fase clínica I fueron sometidos a proctectomía sin terapia preoperatoria.PRINCIPALES MEDIDAS DE RESULTADO:Las medidas primarias fueron la incidencia del sobre-estadiaje histopatológico, la recurrencia (local y sistémica) y la sobrevida general.RESULTADOS:De 94 pacientes en fase clínica I que se sometieron a una proctectomía sin terapia preoperatoria, 23 (24,5%) fueron sobre-estadiados ​​por la histopatología quirúrgica. Hubieron 6 pacientes pT3N0, 8 pT1-2N + y 9 pT3N +. No hubo diferencias significativas en las características demográficas o clínicas entre los pacientes sobre-estadiados ​​y los no sobre-estadiados. De los 6 pacientes que fueron sobre-estadiados en la enfermedad T3N0, ninguno de ellos recibió terapia adyuvante y ninguno recidivó. De los 17 pacientes que fueron sobre-estadiados a la enfermedad N +, 14 (82%) recibieron quimioterapia adyuvante y 6 (35%) recibieron quimio-radioterapia adyuvante. Ninguno desarrolló recidiva local, pero 4 (24%) desarrollaron recidiva sistémica y 2 (12%) murieron a causa de la enfermedad durante el seguimiento medio de 36 meses. Entre los 9 pacientes con pT3N +, la tasa de recidiva sistémica fue del 33%, a pesar de que 8 de 9 pacientes recibieron fluorouracilo, leucovorina y oxaliplatino como quimio-adyuvantes.LIMITACIONES:El tamaño pequeño de la muestra dificulta la capacidad de obtener conclusiones significativas.CONCLUSIONES:Uno de cada cuatro pacientes con cáncer de recto en estadío I presentaba enfermedad ganglionar o T3 no descrita en la histopatología operatoria. La enfermedad ganglionar oculta se asoció con peores resultados, a pesar de recibir terapia adyuvante. La recidiva sistémica fue más común que la recidiva local. Consulte Video Resumen en http://links.lww.com/DCR/B885 . (Traducción-Dr. Xavier Delgadillo ).

A Multicenter Phase 1 Trial Evaluating Nanoliposomal Irinotecan for Heated Intraperitoneal Chemotherapy Combined with Cytoreductive Surgery for Patients with Peritoneal Surface Disease.

BACKGROUND: Nanoliposomal irinotecan (nal-IRI) is a promising novel hyperthermic intraperitoneal chemotherapy (HIPEC) agent given its enhanced efficacy against gastrointestinal tumors, safety profile, thermo-synergy, and heat stability. This report describes the first in-human phase 1 clinical trial of nal-IRI during cytoreductive surgery (CRS) and HIPEC. METHODS: Patients with peritoneal surface disease (PSD) from appendiceal and colorectal neoplasms were enrolled in a 3 + 3 dose-escalation trial using nal-IRI (70-280 mg/m2) during HIPEC for 30 min at 41 ± 1 °C. The primary outcome was safety. The secondary outcomes were pharmacokinetics (PK) and disease-free survival. Adverse events (AEs) categorized as grade 2 or higher were recorded. The serious AEs (SAEs) were mortality, grade ≥ 3 AEs, and dose-limiting toxicity (DLT). Irinotecan and active metabolite SN38 were measured in plasma and peritoneal washings. RESULTS: The study enrolled 18 patients, who received nal-IRI during HIPEC at 70 mg/m2 (n = 3), 140 mg/m2 (n = 6), 210 mg/m2 (n = 3), and 280 mg/m2 (n = 6). No DLT or mortality occurred. The overall morbidity for CRS/HIPEC was 39% (n = 7). Although one patient experienced neutropenia, no AE (n = 131) or SAE (n = 3) was definitively attributable to nal-IRI. At 280 mg/m2, plasma irinotecan and SN38 measurements showed maximum concentrations of 0.4 ± 0.6 µg/mL and 3.0 ± 2.4 ng/mL, a median time to maximum concentration of 24.5 and 26 h, and areas under the curve of 22.6 h*µg/mL and 168 h*ng/mL, respectively. At the 6-month follow-up visit, 83% (n = 15) of the patients remained disease-free. CONCLUSIONS: In this phase 1 HIPEC trial (NCT04088786), nal-IRI was observed to be safe, and PK profiling showed low systemic absorption overall. These data support future studies testing the efficacy of nal-IRI in CRS/HIPEC.

Perioperative Blood Transfusions Are Associated With Worse Overall Survival But Not Disease-Free Survival After Curative Rectal Cancer Resection: A Propensity Score-Matched Analysis.

BACKGROUND: The effects of blood transfusions on oncologic outcomes after surgery remain inconclusive. Thus, we examined the association between receiving a perioperative blood transfusion and oncologic outcomes in patients undergoing curative rectal cancer resection. OBJECTIVE: The purpose of this study was to assess the association between receiving a perioperative blood transfusion with disease-free and overall survival in patients undergoing curative resection of clinical stage I to III rectal cancer. We hypothesized that blood transfusion is associated with worse disease-free and overall survival in this patient cohort. DESIGN: This was a retrospective cohort study using a propensity score-matched analysis. SETTINGS: The study involved 6 tertiary academic medical centers in the United States contributing to the United States Rectal Cancer Consortium. PATIENTS: Patients who underwent curative resection for rectal cancer from 2010 to 2018 were included. MAIN OUTCOME MEASURES: The primary outcome was disease-free survival. The secondary outcomes were overall survival, intensive care unit length of stay, hospital length of stay, surgical site infection, and readmission. RESULTS: Of the 924 patients eligible for matching, 312 patients were matched, including 100 patients who received a transfusion and 212 who did not. In a propensity score-matched analysis, receiving a perioperative blood transfusion was not associated with worse 5-year disease-free survival (transfused, 78%; not transfused, 83%; p = 0.32) but was associated with worse 5-year overall survival (transfused 65% vs not transfused 86%; p < 0.001) and increased hospital length of stay (transfused, 9.9 d; not transfused, 7.6 d; p = 0.001). LIMITATIONS: Despite propensity matching, confounding may remain. Propensity matching may limit the power to detect a difference in disease-free survival. CONCLUSIONS: Receiving a perioperative blood transfusion is not associated with worse disease-free survival but is associated with worse overall survival. Such findings are important for clinicians and patients to understand when considering perioperative blood transfusions. See Video Abstract at http://links.lww.com/DCR/B531. LAS TRANSFUSIONES DE SANGRE PERIOPERATORIAS SE ASOCIAN CON UNA PEOR SOBREVIDA GLOBAL, PERO NO CON LA SOBREVIDA LIBRE DE ENFERMEDAD POSTERIOR A LA RESECCIN CURATIVA DEL CNCER DE RECTO UN PUNTAJE DE PROPENSIN POR ANLISIS DE CONCORDANCIA: ANTECEDENTES:El impacto de las transfusiones de sangre en los resultados oncológicos posteriores a la cirugía no son concluyentes. Por lo anterior, estudiamos la asociación entre recibir una transfusión de sangre perioperatoria y los resultados oncológicos en pacientes llevados a resección curativa de cáncer de recto.OBJETIVO:El propósito de este estudio fue evaluar la asociación entre recibir una transfusión de sangre perioperatoria con la sobrevida libre de enfermedad y la sobrevida general en pacientes llevados a resección curativa de cáncer de recto en estadio clínico I-III. Nuestra hipótesis es que la transfusión de sangre se asocia con una peor sobrevida global y libre de enfermedad en esta cohorte de pacientes.DISEÑO:Es un estudio de cohorte retrospectivo que utilizó un puntaje de propensión por análisis de concordancia.AMBITO:El estudio se realizó en seis centros médicos académicos de tercer nivel en los Estados Unidos que contribuían al Consorcio de Cáncer de Recto de los Estados Unidos.PACIENTES:Se incluyeron pacientes que fueron llevados a resección curativa por cáncer de recto entre 2010 y 2018.PRINCIPALES VARIABLES EVALUADAS:El objeitvo principal fue la sobrevida libre de enfermedad. Los objetivos secundarios fueron la sobrevida global, el tiempo de estancia en la unidad de cuidados intensivos, el tiempo de la estancia hospitalaria, la infección del sitio quirúrgico y el reingreso.RESULTADOS:De los 924 pacientes elegibles para el emparejamiento, se emparejaron 312 pacientes, incluidos 100 pacientes que recibieron una transfusión y 212 que no. En el puntaje de propensión por análisis de concordancia, recibir una transfusión de sangre perioperatoria no se asoció con una peor sobrevida libre de enfermedad a 5 años (TRANSFUSIÓN 78%; NO TRANSFUSIÓN 83%; p = 0,32), pero se asoció con una peor sobrevida global a 5 años (TRANSFUSION 65% vs NO TRANSFUSION 86%; p <0,001) y aumento de la estancia hospitalaria (TRANSFUSIÓN 9,9 días; NO TRANSFUSION 7,6 días; p = 0,001).LIMITACIONES:A pesar de la concordancia de propensión, pueden existir desviaciones. El emparejamiento de propensión puede limitar el poder para detectar una diferencia en la sobrevida libre de enfermedad.CONCLUSIONES:Recibir una transfusión de sangre perioperatoria no se asocia con una peor sobrevida libre de enfermedad, pero sí con una peor sobrevida global. Es importante que los médicos y los pacientes comprendan estos hallazgos al considerar las transfusiones de sangre perioperatorias. Consulte Video Resumen en http://links.lww.com/DCR/B531. (Traducción-Dr Lisbeth Alarcon-Bernes).

A US Rectal Cancer Consortium Study of Inferior Mesenteric Artery Versus Superior Rectal Artery Ligation: How High Do We Need to Go?

BACKGROUND: The optimal level of pedicle ligation during proctectomy for rectal cancer, either at the origin of the inferior mesenteric artery or the superior rectal artery, is still debated. OBJECTIVE: The objective was to determine whether superior rectal artery ligation portends equivalent technical or oncologic outcomes. DESIGN: This was a retrospective analysis of a rectal cancer database (2007-2017). SETTINGS: The study was conducted at 6 tertiary referral centers in the United States (Emory University, University of Michigan, University of Pittsburgh Medical Center, The Ohio State University Wexner Medical Center, Vanderbilt University Medical Center, and Washington University School of Medicine in St. Louis). PATIENTS: Patients with primary, nonmetastatic rectal cancer who underwent low anterior resection or abdominoperineal resection were included. MAIN OUTCOME MEASURES: Anastomotic leak, lymph node harvest, locoregional recurrence-free survival, recurrence-free survival, and overall survival were measured. RESULTS: Of 877 patients, 86% (n = 755) received an inferior mesenteric artery ligation, whereas 14% (n = 122) received a superior rectal artery ligation. A total of 12%, 33%, 24%, and 31% were pathologic stage 0, I, II, and III. Median follow-up was 31 months. Superior rectal artery ligation was associated with a similar anastomotic leak rate compared with inferior mesenteric artery ligation (9% vs 8%; p = 1.0). The median number of lymph nodes removed was identical (15 vs 15; p = 0.38). On multivariable analysis accounting for relevant clinicopathologic factors, superior rectal artery ligation was not associated with increased anastomotic leak rate, worse lymph node harvest, or worse locoregional recurrence-free survival, recurrence-free survival, or overall survival (all p values >0.1). LIMITATIONS: This was a retrospective design. CONCLUSIONS: Compared with inferior mesenteric artery ligation, superior rectal artery ligation is not associated with either worse technical or oncologic outcomes. Given the potential risks of inadequate blood flow to the proximal limb of the anastomosis and autonomic nerve injury, we advocate for increased use of superior rectal artery ligation. See Video Abstract at http://links.lww.com/DCR/B646. ESTUDIO DEL CONSORCIO DE CNCER DE RECTO DE ESTADOS UNIDOS DE LIGADURA BAJA DE LA ARTERIA MESENTRICA INFERIOR CONTRA LIGADURA ALTA DE LA ARTERIA MESENTRICA INFERIOR QU TAN ALTO DEBEMOS EXTENDERNOS: ANTECEDENTES:el nivel óptimo de la ligadura del pedículo en la proctectomía para el cáncer de recto, ya sea en el origen de la arteria mesentérica inferior o en la arteria rectal superior aún no esta definido.OBJETIVO:El objetivo era determinar si la ligadura de la arteria rectal superior pronostica resultados técnicos u oncológicos similares.DISEÑO:Análisis retrospectivo de una base de datos de cáncer de recto (2007-2017).ESCENARIO:el estudio se realizó en seis centros de referencia de tercer nivel en los Estados Unidos (Universidad de Emory, Universidad de Michigan, Centro médico de la Universidad de Pittsburgh, Centro médico Wexner de la Universidad Estatal de Ohio, Centro médico de la Universidad de Vanderbilt y Escuela de Medicina de la Universidad de Washington en St. Louis).PACIENTES:Se incluyeron pacientes con cáncer de recto primario no metastásico que se sometieron a resección anterior baja o resección abdominoperineal.PRINCIPALES VARIABLES ANALIZADAS:Se midió la fuga anastomótica, los ganglios linfáticos recuperados, la sobrevida sin recidiva locorregional, la sobrevida sin recidiva y la sobrevida global.RESULTADOS:De 877 pacientes, en el 86% (n = 755) se realizó una ligadura de la arteria mesentérica inferior, y en el 14% (n = 122) se realizó una ligadura de la arteria rectal superior. El 12%, 33%, 24% y 31% estaban en estadio patológico 0, I, II y III respectivamente. La mediana de seguimiento fue de 31 meses. La ligadura de la arteria rectal superior se asoció con una tasa de fuga anastomótica similar a la ligadura de la arteria mesentérica inferior (9 vs 8%, p = 1,0). La mediana del número de ganglios linfáticos extirpados fue idéntica (15 contra 15, p = 0,38). En el análisis multivariado que tiene en cuenta los factores clínico-patológicos relevantes, la ligadura de la arteria rectal superior no se asoció con una mayor tasa de fuga anastomótica, una peor cosecha de ganglios linfáticos o una peor sobrevida libre de recurrencia locorregional, sobrevida libre de recurrencia o sobrevida global (todos p> 0,1).LIMITACIONES:Diseño retrospectivo.CONCLUSIONES:En comparación con la ligadura de la arteria mesentérica inferior, la ligadura de la arteria rectal superior no se asocia a peores resultados técnicos ni oncológicos. Debido a los riesgos potenciales de un flujo sanguíneo inadecuado del muñon proximal de la anastomosis y la lesión de los nervios autonómicos, proponemos una mayor realización de la ligadura de la arteria rectal superior. Consulte Video Resumen en http://links.lww.com/DCR/B646.

Targeting BRAF Mutations in High-Grade Neuroendocrine Carcinoma of the Colon.

Mutations in the RAS/RAF/MEK/ERK pathway leading to constitutive activation and uncontrolled cellular growth have been identified in various human malignancies, making this pathway a target for potential therapeutics. The activating BRAFV600E mutation is one well-characterized oncogenic mutation that has been described and targeted with clinical success in various malignancies, including melanoma and hairy cell leukemia. Although BRAF-directed treatments have yielded clinical benefit in a subset of tumor types, such as melanoma, thyroid cancer, and lung cancer, BRAF inhibition fails to confer a clinical benefit in colon cancer. Identification of patients for whom BRAF inhibition may produce clinically meaningful outcomes is imperative. The incidence of BRAF mutations in neuroendocrine carcinoma (NEC) is estimated to be 5% to 10%. A recent case series demonstrated benefit in targeting the BRAFV600E mutation in metastatic high-grade rectal NECs. Combination BRAF and MEK inhibition is known to yield improved outcomes compared with BRAF inhibition alone in melanoma. This report presents 2 patients with high-grade colorectal NECs who had different responses to treatment with combined BRAF/MEK inhibition after experiencing disease progression through first-line platinum-based chemotherapy. One patient experienced an excellent initial response to therapy before ultimately experiencing progression, and in the other patient initially had stable disease before eventually experiencing progression. These cases highlight the complicated role BRAF mutations play in gastrointestinal NECs, and the need for further research to identify not only patients who may benefit from BRAF-directed therapies but also strategies to avoid development of resistance.

Combination therapy with capecitabine and temozolomide in patients with low and high grade neuroendocrine tumors, with an exploratory analysis of O6-methylguanine DNA methyltransferase as a biomarker for response.

Recent advances in the treatment of neuroendocrine tumors (NET), including the combination regimen of capecitabine and temozolomide (CAPTEM), have mostly focused on grade 1 and 2 pancreatic neuroendocrine tumors (pNET). We undertook a retrospective review of 38 patients with advanced NET treated with CAPTEM, including patients with non-pancreatic tumors as well as grade 2 and 3 tumors. O6-methylguanine DNA methyltransferase (MGMT) expression was assessed as a predictive biomarker. We found that CAPTEM demonstrated activity in patients with all grades and in pNET and non-pNET. Median progression free survival (mPFS) was 13.0 months (95% CI: 5.6-17.0) and median overall survival (mOS) 29.3 months (95% CI 17.7 - 45.3). Among evaluable patients, there were 11 (38%) partial responses, 15 (52%) stable disease, and 3 (10%) progressive disease for a disease control rate of 90%. A higher rate of partial responses occurred in patients whose tumors had low levels of MGMT expression (63%) compared to intermediate-high (17%) (p=0.19). Our results show that CAPTEM therapy is active in patients with NET including in previously treated patients and in those with poorly-differentiated histology. We observed a trend towards increased response rate, median PFS, and median OS in patients whose tumors had low MGMT protein expression.

A Prospective Randomized Multicenter Trial of Distal Pancreatectomy With and Without Routine Intraperitoneal Drainage.

OBJECTIVE: The objective of this study was to test the hypothesis that distal pancreatectomy (DP) without intraperitoneal drainage does not affect the frequency of grade 2 or higher grade complications. BACKGROUND: The use of routine intraperitoneal drains during DP is controversial. Prior to this study, no prospective trial focusing on DP without intraperitoneal drainage has been reported. METHODS: Patients undergoing DP for all causes at 14 high-volume pancreas centers were preoperatively randomized to placement of a drain or no drain. Complications and their severity were tracked for 60 days and mortality for 90 days. The study was powered to detect a 15% positive or negative difference in the rate of grade 2 or higher grade complications. All data were collected prospectively and source documents were reviewed at the coordinating center to confirm completeness and accuracy. RESULTS: A total of 344 patients underwent DP with (N = 174) and without (N = 170) the use of intraperitoneal drainage. There were no differences between cohorts in demographics, comorbidities, pathology, pancreatic duct size, pancreas texture, or operative technique. There was no difference in the rate of grade 2 or higher grade complications (44% vs. 42%, P = 0.80). There was no difference in clinically relevant postoperative pancreatic fistula (18% vs 12%, P = 0.11) or mortality (0% vs 1%, P = 0.24). DP without routine intraperitoneal drainage was associated with a higher incidence of intra-abdominal fluid collection (9% vs 22%, P = 0.0004). There was no difference in the frequency of postoperative imaging, percutaneous drain placement, reoperation, readmission, or quality of life scores. CONCLUSIONS: This prospective randomized multicenter trial provides evidence that clinical outcomes are comparable in DP with or without intraperitoneal drainage.

Neoadjuvant Therapy for Rectal Cancer Affects Lymph Node Yield and Status Without Clear Implications on Outcome: The Case for Eliminating a Metric and Using Preoperative Staging to Guide Therapy.

BACKGROUND: Nodal status has long been considered pivotal to oncologic care, staging, and management. This has resulted in the establishment of rudimentary metrics regarding adequate lymph node yield in colon and rectal cancers for accurate cancer staging. In the era of neoadjuvant treatment, the implications of lymph node yield and status on patient outcomes remains unclear. PATIENT AND METHODS: This study included 1,680 patients with locally advanced rectal cancer from the NCCN prospective oncology database stratified into 3 groups based on preoperative therapy received: no neoadjuvant therapy, neoadjuvant chemoradiation, and neoadjuvant chemotherapy. Clinicopathologic characteristics and survival were compared between the groups, with univariate and multivariate analyses undertaken. RESULTS: The clinicopathologic characteristics demonstrated statistically significant differences and heterogeneity among the 3 groups. The neoadjuvant chemoradiation group demonstrated the statistically lowest median lymph node yield (n=15) compared with 17 and 18 for no-neoadjuvant and neoadjuvant chemotherapy, respectively (P<.0001). Neoadjuvant treatment did impact survival, with chemoradiation demonstrating increased median overall survival of 42.7 compared with 37.3 and 26.6 months for neoadjuvant chemotherapy and no-neoadjuvant therapy, respectively (P<.0001). Patients with a yield of fewer than 12 lymph nodes had improved median overall survival of 43.3 months compared with 36.6 months in patients with 12 or more lymph nodes (P=.009). Multivariate analysis demonstrated that neither node yield nor status were predictors for overall survival. DISCUSSION: This analysis reiterates that nodal yield in rectal cancer is multifactorial, with neoadjuvant therapy being a significant factor. Node yield and status were not significant predictors of overall survival. A nodal metric may not be clinically relevant in the era of neoadjuvant therapy, and guidelines for perioperative therapy may need reconsideration.

Changing intraoperative parathyroid hormone collection sites from peripheral to central does not affect predictive accuracy during minimally invasive parathyroidectomy.

BACKGROUND: Intraoperative parathyroid hormone (ioPTH) monitoring (IPM) is vital to minimally invasive parathyroidectomy. Techniques vary in assay sampling, potentially affecting predictive accuracy of operative success. Initial guidelines were established using peripheral sites, but central sites may be preferred or necessary when peripheral access is not feasible. We hypothesize that changing collection sites from preexcision peripheral sites to postexcision central sites would not affect IPM accuracy. METHODS: Analysis of 64 consecutive patients who underwent parathyroidectomy for primary hyperparathyroidism was undertaken. PTH assays were collected simultaneously from a peripheral vein (PV) and central vein (CV) preexcision and at a 10-min interval after initial parathyroid excision. IPM success was defined as PTH decrease ≥50% 10 min after initial excision. Predictive accuracy was determined by the need to resect another abnormal gland and biochemical normalization in the postoperative clinic. Receiver operating characteristic (ROC) method with area under the curve (AUC) compared diagnostic accuracy of different assay approaches. RESULTS: Centrally, a statistically higher mean pre- and postexcision ioPTH of 391 pg/ml and 58 pg/ml was found compared with peripheral means of 156 pg/ml and 49 pg/ml, respectively (p < 0.001). The AUC when changing from a PV preexcision to a CV postexcision ioPTH was 0.89, comparable to AUC for peripheral or central assay collections alone (AUC = 0.83 and 0.85, respectively). CONCLUSIONS: This study suggests that altering collection sites does not alter assay validity. In cases where peripheral sampling is compromised, changing from a peripheral to central sites will not likely alter the predictive accuracy of IPM significantly.

Failure of normalization of CA19-9 following resection for pancreatic cancer is tantamount to metastatic disease.

BACKGROUND: Multidisciplinary therapy for pancreatic cancer involves radical resection followed by gemcitabine-based chemotherapy. Carbohydrate antigen 19-9 (CA19-9), when elevated preoperatively, is a useful marker to monitor disease status following resection. However, little has been reported on outcomes of patients in whom CA19-9 never normalizes. We hypothesize that failure of CA19-9 normalization within 6 months is prognostically equivalent to metastatic disease. METHODS: From our pancreatectomy database, we identified 93 patients with pancreatic adenocarcinoma and elevated CA19-9 prior to resection with levels recorded postoperatively. Patients were grouped based on normalization or persistent elevation of CA19-9 at 6 months after resection. CA19-9 levels normalized (≤35 u/ml) after resection in 38 (41%) and remained elevated in 55 (59%). Clinicopathologic characteristics were compared using Student's t-test and contingency table analyses. Survival curves were constructed using Kaplan-Meier method and compared by log-rank analysis. Cox regression was used to determine predictors of survival. RESULTS: The two groups had comparable clinicopathologic characteristics except for nodal status and perineural invasion, which were higher in patients with persistently elevated CA19-9. Persistent CA19-9 conferred shorter median overall survival of 10.8 months compared with 23.8 months in patients with normalization (p < 0.001), which persisted when controlling for nodal status. Multivariate analysis demonstrated persistently elevated CA19-9 as the sole statistically significant negative predictor of survival [hazard ratio (HR) 2.20, p = 0.002]. CONCLUSIONS: Persistent CA19-9 elevation after pancreatectomy correlates with shorter survival analogous to unresected or metastatic disease and should be regarded as persistent disease regardless of radiographic findings. These patients should be considered for accrual to clinical trials or initiation of alternative therapy.

Liver anatomy.

Understanding the complexities of the liver has been a long-standing challenge to physicians and anatomists. Significant strides in the understanding of hepatic anatomy have facilitated major progress in liver-directed therapies--surgical interventions, such as transplantation, hepatic resection, hepatic artery infusion pumps, and hepatic ablation, and interventional radiologic procedures, such as transarterial chemoembolization, selective internal radiation therapy, and portal vein embolization. Without understanding hepatic anatomy, such progressive interventions would not be feasible. This article reviews the history, general anatomy, and the classification schemes of liver anatomy and their relevance to liver-directed therapies.