Effects of establishing a multidisciplinary pancreatic cancer clinic on time-to-treatment

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Background: Despite recent advances, pancreatic cancer remains an exceedingly morbid disease. This is often attributed to the lack of effective screening tools and the consequent late presentation of patients. The best prognosis is reserved for patients with resectable tumors thus highlighting the importance of swift evaluation and the initiation of treatment following a diagnosis. Multidisciplinary clinics allow for the expedient evaluation of patients by different subspecialties in the same day. Methods: A newly designed, multidisciplinary workflow (MDC-multidisciplinary care clinic) for patients recently diagnosed with pancreatic adenocarcinoma was established at a single, tertiary-care comprehensive cancer center in September of 2021. Patients presenting to MDC undergo same day consultation by surgical oncology, medical oncology, receive genetics counseling and testing, nutrition counseling, and additional support services as indicated. Patients from a prospectively maintained database were compared from before (n = 14) and after (n = 30) implementation of the new workflow. Average time to provider consultation, port placement, and initiation of neoadjuvant chemotherapy were compared using student’s t-test. Results: After a biopsy diagnosis of pancreatic adenocarcinoma, the time interval from initial surgical consultation to initial medical oncology consultation improved from 7d to 1d ( p=.003) with the implementation of MDC. Over 90% of patients were seen on the same day after the MDC was established, compared to just 7% before. There was no difference in the time from initial biopsy diagnosis to initial surgical consultation, biopsy to initial medical oncology consultation, biopsy to port placement, or biopsy to chemotherapy initiation. Conclusions: In this early experience with a new pancreatic cancer multidisciplinary clinic, patients experienced improvements in time to subspecialty evaluation by nearly 7 days. Additionally, prospective data on oncologic outcomes and patient quality-of-care metrics are ongoing; however, this quality improvement effort has already reduced patient burdens in accessing timely care. Our continued efforts focus on further improving care coordination along the entire patient cancer care trajectory.

Abstract 3609: Differential gene expression is associated with response to chemoradiation and relapse-free and overall survival in rectal adenocarcinoma

Background: Neoadjuvant chemoradiation is a standard therapy for stage II-III rectal adenocarcinoma, and the degree of pathologic response observed upon resection informs prognosis. However, there is a need to identify novel biomarkers of response to chemoradiation and survival after chemoradiation, particularly using modern next-generation sequencing methods.

Methods: We prospectively collected pretreatment endoscopic tumor biopsies from 43 patients with stage II-IV rectal adenocarcinoma prior to neoadjuvant chemoradiation with concurrent fluoropyrimidine. Tumor samples were fresh frozen, and subsequently RNA was extracted, paired end libraries for mRNA sequencing (RNASeq) were prepared using TruSeq RNA Access library prep kits (Illumina), and samples were sequenced on Illumina HiSeq. Differentially expressed genes were determined using DESeq2 and Ingenuity pathway analysis (Qiagen) was performed. Additionally, the association between “claudin-low”-like gene sets established in breast and bladder cancers and clinical outcomes was determined.

Results: Among the 36 patients with adequate RNA quality, 7 had a pathologic complete response (pCR) and 29 did not, with 22 differentially expressed genes with false discovery rate (FDR) <0.1 between the two cohorts, including EME2 (2.0-fold change, FDR p-value 0.00627). At 5 years of follow-up, 11 patients had known relapse and 11 were known to be relapse-free, with 33 differentially expressed genes with FDR<0.1 between the two cohorts. Pathway analysis demonstrated that p53 signaling and Wnt/β-catenin signaling pathways were associated with relapse, while dendritic cell maturation and Toll-like receptor signaling pathways were associated with relapse-free survival. Rectal cancers with greater expression of a “claudin-low”-like signature had significantly inferior relapse-free survival (HR 1.79, 95% CI 1.07-3.00) and overall survival (HR 1.91, 95% CI 1.17-3.12) on univariate Cox proportional hazards model.

Conclusions: There are multiple differentially expressed genes associated with response to neoadjuvant chemoradiation in rectal adenocarcinoma. EME2, which forms an endonuclease that cleaves stalled replication forks, was one of the most differentially expressed genes overexpressed in patients with pathologic complete response and thus is a rational target for further investigation. Extension of “claudin-low” gene expression signatures to rectal cancers may serve as a new prognostic biomarker. Further investigation into the association of gene expression subtypes and responses to neoadjuvant chemoradiation is warranted.

Citation Format: Michael S. Lee, Cheryl Carlson, Benjamin F. Calvo, Bert H. O'Neil, Dante S. Bortone, Benjamin G. Vincent. Differential gene expression is associated with response to chemoradiation and relapse-free and overall survival in rectal adenocarcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 3609.

Association of differential mucosal microbiome composition with clinicopathologic characteristics of rectal adenocarcinoma

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Background: Alterations in gut microbial composition are associated with development and progression of colorectal cancer (CRC), and may contribute to interpatient biologic and clinical heterogeneity. While recent studies have emphasized primary CRC tumor site as explaining much of these differences, there is still marked heterogeneity in clinical outcomes among the more homogeneous subgroup of rectal cancers. As such, we hypothesized that differential mucosal microbial populations are associated with distinct clinicopathologic characteristics among patients with locally advanced rectal cancer. Methods: Patients with T3-4 or N+ rectal adenocarcinoma were prospectively identified and underwent endoscopic tumor biopsy before starting neoadjuvant chemoradiation. Tumor samples were fresh frozen, bacterial DNA was extracted, and the V1-V2 region of the 16S bacterial ribosomal RNA was sequenced (IonTorrent). Sequences were processed through QIIME and an average of 16,189 reads per sample was obtained after quality filtering. Multivariate analyses were conducted using PRIMER VII and SPSS v24 software. P-values were determined using Mann-Whitney tests, and Benjamini-Hochberg procedure for false discovery rate was used and only results with false discovery rate < 0.25 are presented. Results: Among the 37 patients, mean age at diagnosis was 54 (range 30-77) and pre-treatment clinical stage was II (30%) vs. III-IV (70%). Younger patients (age < 50) had samples underrepresented for Streptococcus (0.9% vs 7.1%, p = 0.016, FDR 0.224) genus. Higher clinical stage was associated with enrichment of Fusobacterium (16.2% vs 5.6%, p = 0.019) and Parvimonas (4.6% vs 1.4%, p = 0.033) genera. Conclusions: Differential composition of tumor mucosal microbiota is associated with key clinical features among rectal adenocarcinomas, including age of diagnosis and tumor stage. Further investigation to determine associations between gut dysbiosis and transcriptomic subtypes may shed light on etiology of interpatient heterogeneity of rectal cancers.

Phase Ib/II study of neoadjuvant chemoradiotherapy with CRLX101 and capecitabine for locally advanced rectal cancer

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Background: There is strong interest in the development of novel agents to further improve the therapeutic ratio of neoadjuvant chemoradiotherapy for rectal cancer. CRLX101 is an investigational nanoparticle-drug conjugate with a camptothecin payload. The purpose of this Phase Ib/II study is to assess toxicity and to evaluate whether the addition of CRLX101 to chemoradiotherapy can improve pathologic complete response (pCR) for rectal cancer. Methods: This is a single-arm multicenter Phase Ib/II study examining the addition of CRLX101 to a standard capecitabine-based chemoradiotherapy regimen. Phase Ib employs a 3+3 dose escalation design with starting dose of 12 mg/m2 every other week (QOW). Dose level +1 was 15 mg/m2 (MTD for CRLX101 single agent QOW). Upon reaching MTD for QOW dosing, protocol was modified to evaluate QW CRLX101 dosing starting at 12 mg/m2 and 15 mg/m2as +1 level. Secondary endpoints included pCR and clinical outcome. Results: A total of 32 patients were enrolled on the trial. 26/32 had T3-4, 9/32 had N2 and 16/32 had N1 disease. For QOW dosing, 9 patients completed treatment without DLT and MTD was identified as 15 mg/m2 QOW. 14 patients were treated on the Phase II portion of the study at 15 mg/m2 QOW prior to the initiation of weekly dosing Phase Ib cohorts. For QW dosing, 0/3 patients experienced DLT at 12 mg/m2 and 1/6 patients experienced DLT at 15 mg/m2. The DLT was skin desquamation requiring treatment delay. QW MTD was identified as 15 mg/m2. Toxicities (all grade 3 except lymphopenia) that could possibly be attributed to CRLX101 are in Table 1. Full clinical and pathologic staging were available for 29/32 patients. Mean neoadjuvant rectal (NAR) score was 19 with standard deviation of 15. At the weekly MTD, 3/6 patients had pCR. Conclusions: CRLX101 weekly at 15 mg/m2+ standard capecitabine-based chemoradiotherapy appears to be well tolerated, with promising pCR rates that warrants further evaluation. A larger PhII trial should be considered with this regimen. Clinical trial information: NCT02010567. [Table: see text]

Abstract 5515: Neoadjuvant chemoradiotherapy for rectal cancer with CRLX101, an investigational nanoparticle-drug conjugate with a camptothecin payload

Background: There has been great interest in developing novel agents and strategies to improve chemoradiotherapy (CRT) for locally advanced rectal cancer. Irinotecan, a campothecin (CPT) analogue, held high potential, but the combination was clinically infeasible due to severe gastrointestinal toxicities. CRLX101, is an investigational nanoparticle drug conjugate (NDC). Preclinical experiments showed that CRLX101 differentially delivers CPT into cancer cells and appears to durably suppress HIF-1α as well as topoisomerase 1, but with less gastrointestinal toxicities than irinotecan. We therefore hypothesized that the addition of CRLX101 to rectal CRT (5-FU + XRT) may further improve the therapeutic index in this setting.

Methods: Synergy with CRLX101 in combination with either XRT or CRT was studied in vitro (SW480 and HT29 colorectal cancer cell lines) and in vivo (murine flank xenograft models). Skin toxicity and hematologic toxicity were also characterized. In order to test the synergy hypothesis in the clinic, a Phase Ib/II clinical trial (LCCC1315) evaluating the addition of CRLX101 to CRT in the neo-adjuvant treatment of rectal cancer is currently underway. A standard 3 + 3 design is being employed for the phase Ib with a CRLX101 starting dose of 12 mg/m2 in the first cohort escalating to the CRLX101 monotherapy MTD of 15 mg/m2 in the second. The primary phase 2 end-point is the pathological complete response (pCR) rate from treatment.

Results: CRLX101 was found to be as potent as camptothecin in vitro. We have demonstrated that CRLX101 functions by inhibition of both DNA repair and HIF-1α signaling. The addition of CRLX101 to radiotherapy increased and prolonged the number of γH2AX foci, even at 24 hours post radiotherapy. We also confirmed that CRLX101 decreased HIF-1α and its downstream targets VEGF and carbonic anhydrase IX in mice bearing HT29 xenografts. Our findings were further validated in vivo: we demonstrated that both CRLX101+5FU+XRT and CRLX101+XRT delayed tumor growth more than other regimens (p-values &lt; 0.05). More importantly, we found CRT with CRLX101+5FU is significantly more effective than CRT with oxaliplatin+5FU (25 days to double tumor volume vs. 11 days), a regimen that has been extensively studied clinically. Preclinical toxicity studies demonstrated that the addition of CRLX101 did not increase hematologic or skin toxicities. In the ongoing clinical trial, none of the first 6 patients enrolled have experienced dose-limiting toxicities, and 1 out of 3 patients who underwent surgery had a pCR. The other 2 patients had extensive treatment response with minimal residual tumor.

Conclusions: Preclinical data suggests that CRLX101 improves the therapeutic index of CRT for rectal cancer. Preliminary clinical data is encouraging, and supports further clinical assessment of CRLX101+5FU+XRT in patients with locally advanced rectal cancer.

Citation Format: XI TIAN, Minh Nguyen, Henry Foote, Kyle T. Wagner, Hanna K. Sanoff, Autumn J. McRee, Bert H. O'Neil, Benjamin F. Calvo, William A. Blackstock, Joel E. Tepper, Edward Garmey, Scott Eliasof, Andrew Z. Wang. Neoadjuvant chemoradiotherapy for rectal cancer with CRLX101, an investigational nanoparticle-drug conjugate with a camptothecin payload. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 5515. doi:10.1158/1538-7445.AM2015-5515

Intraoperative electron radiation therapy as an important treatment modality in retroperitoneal sarcoma

BACKGROUND

Local recurrence (LR) rates in patients with retroperitoneal sarcoma (RPS) are high, ranging from 40% to 80%, with no definitive studies describing the best way to administer radiation. Intraoperative electron beam radiation therapy (IOERT) provides a theoretical advantage for access to the tumor bed with reduced toxicity to surrounding structures. The goal of this study was to evaluate the role of IOERT in high-risk patients.

METHODS

An institutional review board approved, single institution sarcoma database was queried to identify patients who received IOERT for treatment of RPS from 2/2001 to 1/2009. Data were analyzed using the Kaplan-Meier method, Cox regression, and Fisher Exact tests.

RESULTS

Eighteen patients (median age 51 y, 25-76 y) underwent tumor resection with IOERT (median dose 1250 cGy) for primary (n = 13) and recurrent (n = 5) RPS. Seventeen patients received neoadjuvant radiotherapy. Eight high-grade and 10 low-grade tumors were identified. Median tumor size was 15 cm. Four patients died and two in the perioperative period. Median follow-up of survivors was 3.6 y. Five patients (31%) developed an LR in the irradiated field. Three patients with primary disease (25%) and two (50%) with recurrent disease developed an LR (P = 0.5). Four patients with high-grade tumors (57%) and one with a low-grade tumor (11%) developed an LR (P = 0.1). The 2- and 5-y OS rates were 100% and 72%. Two- and 5-y LR rates were 13% and 36%.

CONCLUSIONS

Using a multidisciplinary approach, we have achieved low LR rates in our high-risk patient population indicating that IOERT may play an important role in managing these patients.

Abstract 4527: The HER3-EREG axis and its role in colorectal cancer aggression

Yearly, 50,000 Americans die of colorectal cancer metastases to liver and lung. EGFR-targeted agents improve survival in a subset of metastatic colorectal cancer (mCRC) cases, and overexpression of the HER-family ligands amphiregulin (AREG) and epiregulin (EREG) correlates with EGFR-targeted agent susceptibility. Here we present evidence of association between EREG overexpression and disease aggression by showing that knockdown of EREG or HER3 impede anchorage independent growth in the HCT 116 CRC cell line. We also find that a HER3-EREG axis gene signature groups mCRC tumors into prognostically distinct groups. Snap-frozen CRC hepatic metastases (65) with patient matched normal liver, as well as 71 primary CRC tumors with patient matched normal colonic mucosa were analyzed via qRT-PCR for receptors (HER1-4) and ligands (AREG, and EREG). Among the mCRC cases HER2, HER3, AREG, and EREG were expressed at higher levels than unmatched normal mucosa (p&lt;0.005). HER2, AREG, and EREG were also overexpressed in mCRC compared to unmatched primary CRC tissue (p&lt;0.005). Expression of AREG and EREG were highly correlated (Rs=0.90), and higher EREG mRNA expression was associated with markedly decreased post-hepatectomy overall survival (OS) (p=0.018). In a panel of 9 CRC cell lines HCT 116 had the highest EREG expression. Using the pLKO.1 viral vector, shRNAs targeting EREG, and HER3 were introduced to HCT 116 cells. Empty vector was used as a control. mRNA levels for HER3 and EREG were knocked down by 87% and 73% respectively and protein downregulation was confirmed by western blot. Knockdown and control cells were grown in 0.35% soft agar at a density of 5000 cells per well in 6 well plates. Knockdowns impeded anchorage independent growth with a mean colony count (&gt;50 um diameter) of 170 for HER3, and 285 for EREG as compared to 530 for the empty vector (p&lt;0.005). RNA from 3 distinct sets of HER3, EREG, and empty vector infections was assayed on Agilent Human GE 4x44K v2 microarrays. Unsupervised Principle Component Analysis (PCA) suggested broad concordance in the impact of EREG or HER3 knockdown upon the expression profile. Statistical Analysis of Microarrays (SAM) comparing HER3, and EREG knockdowns to empty vector control revealed 205, and 432 differentially expressed genes with at least a 1.5 fold-change and a false discovery rate of 0%. When HER3 and EREG differential gene lists were compared, 95 overlapping genes with 100% directional agreement were observed. For 51 mCRC cases RNA was available for microarray analysis. A predictor of HER3-EREG activity was constructed from 250 genes that discriminate HER3/EREG knockdown and empty vector control cells and are generally variable in tumors. The predictor was used to assign a HER3-EREG activity score to each mCRC case. This score is significantly associated with OS (p=0.005) with the top 50% of patients by HER3-EREG score demonstrating 5 year OS of 23% as compared to 49% for cases in the lower half of HER3-EREG activity.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 4527. doi:1538-7445.AM2012-4527

KRAS mutation as a prognostic factor in patients undergoing hepatic resection for metastatic colorectal cancer

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Background: It is well known that KRAS mutations limit the efficacy of anti-EGFR therapy in patients with metastatic colorectal cancer (mCRC). However the role of KRAS mutations in patients who undergo a curative liver resection for mCRC is less clear. The purpose of our study was to evaluate the relationship between KRAS mutation status and survival in this patient population.

Methods: We examined an IRB approved tissue repository and retrospective database of 129 patients from 1998-2010 who underwent curative liver resection for mCRC. Tumors were sequenced for KRAS codons 12, 13, and 61 mutations using pyrosequencing. Overall survival (OS) and disease-free survival (DFS) were analyzed using the Kaplan-Meier method and compared using the log-rank test. Multivariate analysis was performed using the Cox proportional hazards regression method.

Results: The median follow-up for our cohort was 20.4mo (0.4-112). Mean age was 61.4±12.3. Prior to surgical resection 55 (43%) patients received chemotherapy. 35 (27%) tumors were KRAS mutant (mt), 83 (64%) were wild-type (wt), and 11 (9%) were not characterized. Median OS for KRAS wt patients was 40.3mo vs. 27.1mo for KRAS mt patients (p=0.046). Median DFS for KRAS wt was 13.6mo vs. 7.7mo for KRAS mt patients (p=0.037). 8 patients received cetuximab post–operatively. Cetuximab status was unknown in 50 patients. When we excluded those treated with cetuximab, the median OS was 40mo for KRAS wt vs. 25mo for KRAS mt patients (p=0.007). There were no differences in OS or DFS in patients who received cetuximab (p=0.7). In a multivariable model with pre-operative chemotherapy (p=0.2), extent of resection (p=0.053), and cetuximab therapy (p=0.7), the presence of KRAS mutation was independently associated with poor prognosis (HR=2.7 [1.3-5.5]).

Conclusions: In patients undergoing curative liver resection for mCRC, KRAS mutation status is independently predictive of a worse outcome regardless of cetuximab therapy. KRAS status may be associated with more aggressive tumor biology. Our data supports the critical need to define KRAS mutation status and to develop therapies against KRAS and its downstream effectors.

Utilization and morbidity associated with placement of a feeding jejunostomy at the time of gastroesophageal resection

BACKGROUND

The purpose of the study was to evaluate the utilization and morbidity associated with feeding jejunostomy tubes (JT) placed at the time of gastroesophageal resection (GER).

METHODS

Under institutional review board approval, a prospective database of patients undergoing GER from January 2004 to September 2010 was reviewed. Data analyzed included patient demographics, postoperative complications, JT use, and JT specific complications. Fisher's exact tests explored associations with utilization of a JT following resection.

RESULTS

Seventy-three patients (51 men, 22 women, median age of 59) underwent placement of a JT at the time of GER (total gastrectomy = 28, Ivor-Lewis = 28, subtotal gastrectomy = 8, proximal gastrectomy  = 6, and transhiatal esophagectomy  = 3) of both malignant (97%) and benign (3%) disease processes. Twenty-one JT specific complications (11 minor and 10 major) were identified. Reoperation was required in the management of two complications (small bowel obstructions), while all other complications were easily managed by an interventional radiologist (n = 8), bedside procedure (n = 5), or did not require intervention (n = 6). Eighty-six percent of patients were discharged tolerating a postgastrectomy diet, 10% nothing per orem, and 4% a liquid diet. Inpatient enteral nutrition (EN) was initiated in 68%, but continued on discharge in only 54% secondary to failure to thrive (54%), dysphagia (21%), anastomic leak (15%), chyle leak (3%), esophagostomy (3%), and duodenal stump leak (3%). The mean time to discontinuance of EN and removal of the JT was 44 days (range, 4-203) and 71 days (range, 15-337) respectively. Although only 13% (n = 5) of patients requiring adjuvant therapy were utilizing their JT at the commencement of therapy, 75% (n = 21) required EN during its course. The median time to adjuvant therapy was found to be slightly longer in those who required outpatient EN versus those who did not (61 vs. 90 days, p = 0.08). However, the median time to adjuvant therapy did not differ between those who were and were not receiving EN at the time of adjuvant therapy commencement (80 vs. 92 days, p = 0.2). Age (p = 0.4), number of co-morbidities (p = 0.2), preoperative percent body weight loss (p = 0.9), and clinical stage (p = 0.8) were not significantly associated with outpatient JT use. Patients who suffered a postoperative complication were most likely to require EN (p = 0.002), an association that strengthened as the number of complications increased (p = 0.0008). Although not statistically significant, a trend towards increased outpatient EN was noted in patients who underwent transhiatal esophagectomy and total gastrectomy (p = 0.06).

CONCLUSIONS

JT placement carries a considerable morbidity in patients undergoing GER. However, because it is difficult to preoperatively ascertain who will need prolonged EN, the routine placement of a JT is recommended, particularly in those who will likely require adjuvant therapy or are at high risk for postoperative complications. Despite patient desires for early removal of an unused JT, caution should be taken if adjuvant therapy is being considered.

Phospho-ERK and AKT status, but not KRAS mutation status, are associated with outcomes in rectal cancer treated with chemoradiotherapy

BACKGROUND

KRAS mutations may predict poor response to radiotherapy. Downstream events from KRAS, such as activation of BRAF, AKT and ERK, may also confer prognostic information but have not been tested in rectal cancer (RC). Our objective was to explore the relationships of KRAS and BRAF mutation status with p-AKT and p-ERK and outcomes in RC.

METHODS

Pre-radiotherapy RC tumor biopsies were evaluated. KRAS and BRAF mutations were assessed by pyrosequencing; p-AKT and p-ERK expression by immunohistochemistry.

RESULTS

Of 70 patients, mean age was 58; 36% stage II, 56% stage III, and 9% stage IV. Responses to neoadjuvant chemoradiotherapy: 64% limited, 19% major, and 17% pathologic complete response. 64% were KRAS WT, 95% were BRAF WT. High p-ERK levels were associated with improved OS but not for p-AKT. High levels of p-AKT and p-ERK expression were associated with better responses. KRAS WT correlated with lower p-AKT expression but not p-ERK expression. No differences in OS, residual disease, or tumor downstaging were detected by KRAS status.

CONCLUSIONS

KRAS mutation was not associated with lesser response to chemoradiotherapy or worse OS. High p-ERK expression was associated with better OS and response. Higher p-AKT expression was correlated with better response but not OS.

Utilization of Interventional Radiology in the Postoperative Management of Patients after Surgery for Locally Advanced and Recurrent Rectal Cancer

The surgical management of locally advanced primary rectal cancer and locally recurrent rectal cancer requires complex operations frequently resulting in complicated postoperative courses. We sought to evaluate the utilization of interventional radiologic (IR) procedures in the management of postoperative complications. Under Institutional Review Board approval, a prospective database of colorectal cancer patients undergoing resection from July 1999 to January 2010 was analyzed. Data collected included demographics, operative procedure, complications, length of stay, and IR utilization. Fisher's exact tests and logistic regression explored associations with necessitating an IR procedure during the postoperative period. Continuous variables were analyzed using Wilcoxon rank sum tests. One hundred and one patients underwent surgery and 66 received intraoperative electron radiotherapy (IOERT). Primary procedures included pelvic exenteration (n = 35), abdominoperineal resection (n = 25), low anterior resection (n = 23), paraaortic node dissection (n = 7), resection of isolated pelvic/retroperitoneal tumor (n = 7), and colectomy (n = 4). Sixty-two patients required multivisceral resection including partial/total cystectomy (n = 30), small bowel resection (n = 25), oophorectomy (n = 15), vaginectomy (n = 12), hysterectomy (n = 12), hepatectomy (n = 3), and nephrectomy (n = 3). Seventeen partial sacral resections and 47 pelvic sidewall resections were also required. One hundred and thirty-eight complications were identified in 72 patients, 30 of which required a procedural intervention. Twenty-seven IR procedures were performed including drainage of fluid collections (n = 14), nephrostomy tube placement (n = 8), arterial embolization (n = 2), inferior vena cava filter placement (n = 2), and pleural drainage (n = 1). Only three reoperations were required, none related to failure of IR procedures. There were no deaths. Estimated blood loss > 2000 mL ( P = 0.002), IOERT ( P = 0.03), and incomplete resection ( P = 0.02) were found to be associated with postoperative IR utilization. Surgery for locally advanced primary rectal cancer and locally recurrent rectal cancer is associated with significant morbidity but low mortality. IR procedures play a significant role in the postoperative management of these patients and may decrease the need for reoperation.

Utilization of interventional radiology in the postoperative management of patients after surgery for locally advanced and recurrent rectal cancer

The surgical management of locally advanced primary rectal cancer and locally recurrent rectal cancer requires complex operations frequently resulting in complicated postoperative courses. We sought to evaluate the utilization of interventional radiologic (IR) procedures in the management of postoperative complications. Under Institutional Review Board approval, a prospective database of colorectal cancer patients undergoing resection from July 1999 to January 2010 was analyzed. Data collected included demographics, operative procedure, complications, length of stay, and IR utilization. Fisher's exact tests and logistic regression explored associations with necessitating an IR procedure during the postoperative period. Continuous variables were analyzed using Wilcoxon rank sum tests. One hundred and one patients underwent surgery and 66 received intraoperative electron radiotherapy (IOERT). Primary procedures included pelvic exenteration (n = 35), abdominoperineal resection (n = 25), low anterior resection (n = 23), paraaortic node dissection (n = 7), resection of isolated pelvic/retroperitoneal tumor (n = 7), and colectomy (n = 4). Sixty-two patients required multivisceral resection including partial/total cystectomy (n = 30), small bowel resection (n = 25), oophorectomy (n = 15), vaginectomy (n = 12), hysterectomy (n = 12), hepatectomy (n = 3), and nephrectomy (n = 3). Seventeen partial sacral resections and 47 pelvic sidewall resections were also required. One hundred and thirty-eight complications were identified in 72 patients, 30 of which required a procedural intervention. Twenty-seven IR procedures were performed including drainage of fluid collections (n = 14), nephrostomy tube placement (n = 8), arterial embolization (n = 2), inferior vena cava filter placement (n = 2), and pleural drainage (n = 1). Only three reoperations were required, none related to failure of IR procedures. There were no deaths. Estimated blood loss > 2000 mL (P = 0.002), IOERT (P = 0.03), and incomplete resection (P = 0.02) were found to be associated with postoperative IR utilization. Surgery for locally advanced primary rectal cancer and locally recurrent rectal cancer is associated with significant morbidity but low mortality. IR procedures play a significant role in the postoperative management of these patients and may decrease the need for reoperation.

Subcutaneous Metastatic Adenocarcinoma: An Unusual Presentation of Colon Cancer - Case Report and Literature Review

Subcutaneous metastasis from a visceral malignancy is rare with an incidence of 5.3%. Skin involvement as the presenting sign of a silent internal malignancy is an even rarer event occurring in approximately 0.8%. We report a case of a patient who presented to her dermatologist complaining of rapidly developing subcutaneous nodules which subsequently proved to be metastatic colon cancer, and we provide a review of the literature.

A phase I study of bortezomib in combination with standard 5-fluorouracil and external-beam radiation therapy for the treatment of locally advanced or metastatic rectal cancer

BACKGROUND

Standard therapy for stage II/III rectal cancer consists of a fluoropyrimidine and radiation therapy followed by surgery. Preclinical data demonstrated that bortezomib functions as a radiosensitizer in colorectal cancer models. The purpose of this study was to determine the maximum tolerated dose (MTD) of bortezomib in combination with chemotherapy and radiation.

PATIENTS AND METHODS

Patients with locally advanced rectal adenocarcinomas, as staged by endoscopic ultrasound, were eligible. Bortezomib was administered on days 1, 4, 8, and 11 every 21 days for 2 cycles with 5-fluorouracil at 225 mg/m2/day continuously and 50.4 Gy of radiation. Dose escalation of bortezomib was conducted via a standard 3 + 3 dose escalation design. A subset of patients underwent serial tumor biopsies for correlative studies.

RESULTS

Nine patients in 2 dose cohorts were enrolled. Diarrhea was the principal dose-limiting toxicity and occurred at the 1.0-mg/m2 dose level. There was no clear evidence of suppression of nuclear factor-kappaB target gene expression in biopsy samples.

CONCLUSION

The MTD of bortezomib in combination with chemotherapy and radiation may be below a clinically relevant dose, limiting the clinical applicability of this combination. Performing biopsies before and during irradiation for determining gene expression in response to radiation therapy is feasible.

A six-gene signature predicts survival of patients with localized pancreatic ductal adenocarcinoma

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) remains a lethal disease. For patients with localized PDAC, surgery is the best option, but with a median survival of less than 2 years and a difficult and prolonged postoperative course for most, there is an urgent need to better identify patients who have the most aggressive disease.

METHODS AND FINDINGS

We analyzed the gene expression profiles of primary tumors from patients with localized compared to metastatic disease and identified a six-gene signature associated with metastatic disease. We evaluated the prognostic potential of this signature in a training set of 34 patients with localized and resected PDAC and selected a cut-point associated with outcome using X-tile. We then applied this cut-point to an independent test set of 67 patients with localized and resected PDAC and found that our signature was independently predictive of survival and superior to established clinical prognostic factors such as grade, tumor size, and nodal status, with a hazard ratio of 4.1 (95% confidence interval [CI] 1.7-10.0). Patients defined to be high-risk patients by the six-gene signature had a 1-year survival rate of 55% compared to 91% in the low-risk group.

CONCLUSIONS

Our six-gene signature may be used to better stage PDAC patients and assist in the difficult treatment decisions of surgery and to select patients whose tumor biology may benefit most from neoadjuvant therapy. The use of this six-gene signature should be investigated in prospective patient cohorts, and if confirmed, in future PDAC clinical trials, its potential as a biomarker should be investigated. Genes in this signature, or the pathways that they fall into, may represent new therapeutic targets. Please see later in the article for the Editors' Summary.

Radiosensitization of epidermal growth factor receptor/HER2-positive pancreatic cancer is mediated by inhibition of Akt independent of ras mutational status

PURPOSE

Epidermal growth factor receptor (EGFR) family members (e.g., EGFR, HER2, HER3, and HER4) are commonly overexpressed in pancreatic cancer. We investigated the effects of inhibition of EGFR/HER2 signaling on pancreatic cancer to elucidate the role(s) of EGFR/HER2 in radiosensitization and to provide evidence in support of further clinical investigations.

EXPERIMENTAL DESIGN

Expression of EGFR family members in pancreatic cancer lines was assessed by quantitative reverse transcription-PCR. Cell growth inhibition was determined by MTS assay. The effects of inhibition of EGFR family receptors and downstream signaling pathways on in vitro radiosensitivity were evaluated using clonogenic assays. Growth delay was used to evaluate the effects of nelfinavir on in vivo tumor radiosensitivity.

RESULTS

Lapatinib inhibited cell growth in four pancreatic cancer cell lines, but radiosensitized only wild-type K-ras-expressing T3M4 cells. Akt activation was blocked in a wild-type K-ras cell line, whereas constitutive phosphorylation of Akt and extracellular signal-regulated kinase (ERK) was seen in lines expressing mutant K-ras. Overexpression of constitutively active K-ras (G12V) abrogated lapatinib-mediated inhibition of both Akt phosphorylation and radiosensitization. Inhibition of MAP/ERK kinase/ERK signaling with U0126 had no effect on radiosensitization, whereas inhibition of activated Akt with LY294002 (enhancement ratio, 1.2-1.8) or nelfinavir (enhancement ratio, 1.2-1.4) radiosensitized cells regardless of K-ras mutation status. Oral nelfinavir administration to mice bearing mutant K-ras-containing Capan-2 xenografts resulted in a greater than additive increase in radiation-mediated tumor growth delay (synergy assessment ratio of 1.5).

CONCLUSIONS

Inhibition of EGFR/HER2 enhances radiosensitivity in wild-type K-ras pancreatic cancer. Nelfinavir, and other phosphoinositide 3-kinase/Akt inhibitors, are effective pancreatic radiosensitizers regardless of K-ras mutation status.

Postoperative Hypocalcemia after Parathyroidectomy for Renal Hyperparathyroidism in the Era of Cinacalcet

Chronic kidney disease is often accompanied by hyperparathyroidism. Cinacalcet, a recent addition to the medical armamentarium, has proven efficacious. It is unclear whether cinacalcet use has any impact on the postoperative course in patients progressing to surgery. The records of 77 patients operated on for renal hyperparathyroidism were reviewed. Sixty-three were treated before the use of cinacalcet and 14 after. Ten subtotal and 67 total parathyroidectomies were performed. Mean nadir serum calcium was similar (6.6 ± 1.3 vs 6.2 ± 1.4 mg/dL). More patients taking cinacalcet preoperatively required intravenous calcium postoperatively (62%) than those treated before its use (41%), although this did not reach statistical significance ( P = 0.09). In those undergoing total parathyroidectomy, cinacalcet use preoperatively (n = 11) led to a lower postoperative nadir calcium (5.8 ± 1.7 vs 6.6 ± 1.3 mg/dL) as compared with those who did not receive it (n = 56) ( P = 0.05). This translated to a greater need for intravenous calcium infusion postoperatively (72 vs 38%) ( P = 0.03). These data suggest a somewhat more aggressive postoperative course in patients who fail calcimimetic and require surgery. This may be useful to inform physicians and patients of expectations postoperatively, although it is not likely to alter management.

Postoperative hypocalcemia after parathyroidectomy for renal hyperparathyroidism in the era of cinacalcet

Chronic kidney disease is often accompanied by hyperparathyroidism. Cinacalcet, a recent addition to the medical armamentarium, has proven efficacious. It is unclear whether cinacalcet use has any impact on the postoperative course in patients progressing to surgery. The records of 77 patients operated on for renal hyperparathyroidism were reviewed. Sixty-three were treated before the use of cinacalcet and 14 after. Ten subtotal and 67 total parathyroidectomies were performed. Mean nadir serum calcium was similar (6.6 +/- 1.3 vs 6.2 +/- 1.4 mg/dL). More patients taking cinacalcet preoperatively required intravenous calcium postoperatively (62%) than those treated before its use (41%), although this did not reach statistical significance (P = 0.09). In those undergoing total parathyroidectomy, cinacalcet use preoperatively (n = 11) led to a lower postoperative nadir calcium (5.8 +/- 1.7 vs 6.6 +/- 1.3 mg/dL) as compared with those who did not receive it (n = 56) (P = 0.05). This translated to a greater need for intravenous calcium infusion postoperatively (72 vs 38%) (P = 0.03). These data suggest a somewhat more aggressive postoperative course in patients who fail calcimimetic and require surgery. This may be useful to inform physicians and patients of expectations postoperatively, although it is not likely to alter management.

Preoperative tyrosine kinase inhibition as an adjunct to debulking nephrectomy

OBJECTIVES

Since the introduction of tyrosine kinase inhibitors (TKI), treatment of metastatic renal cell carcinoma (RCC) has undergone dramatic changes. However, the use of TKI therapy in adjunctive settings remains to be defined. We present a single-institution experience of patients who received preoperative TKI before nephrectomy for metastatic or unresectable disease.

METHODS

The records of 9 patients with locally advanced or metastatic RCC treated with TKI therapy before nephrectomy at the University of North Carolina were reviewed. All procedures and radiographic images were performed at 1 institution. The cases were surveyed for the effect of TKI on tumor burden and surgical approach and timing.

RESULTS

The patients received systemic therapy with either sorafenib or sunitinib before proceeding to nephrectomy on clinical trials for metastatic disease or as the standard of care. The surgery was well tolerated by all patients, without an apparent effect from TKI therapy on the surgical technique or complications. Responses were observed in the primary tumor, as well as in the metastatic sites.

CONCLUSIONS

Neoadjuvant TKI therapy can induce responses in the primary tumor and has the potential advantage of cytoreduction when administered before nephrectomy for RCC. This setting also potentially provides an opportunity to evaluate the TKI responsiveness of patients with metastatic disease. However, prospective trials evaluating adjunctive surgical approaches to locally advanced and metastatic RCC are needed to determine the significant benefits of TKI therapy and to define the optimal agent, timing of therapy, and disease stage to derive benefit for preoperative therapy.

Diabetes mellitus affects response to neoadjuvant chemoradiotherapy in the management of rectal cancer

INTRODUCTION

Although diabetic patients with rectal cancer have poorer outcomes than their nondiabetic counterparts, few studies have looked at diabetics' response to therapy as an explanation for this disparity. This study compares the neoadjuvant chemoradiotherapy (CRT) response in diabetic and nondiabetic patients with locally advanced rectal cancers.

METHODS

This is a single-institution, retrospective review of rectal cancer patients who received CRT followed by resection from 1995 to 2006. Pretreatment tumor-node-metastasis (TNM) staging was determined using endorectal ultrasound, computed tomography (CT) scan, and magnetic resonance imaging (MRI); post-treatment staging was determined by pathological review.

RESULTS

110 patients were included; seventeen had diabetes and 93 were nondiabetics. Pretreatment staging was similar in both groups. Sixteen of the diabetics (94%) completed CRT compared to 92% (86/93) of the nondiabetics. Tumor downstaging rates were similar in the two groups (53% in diabetics, 52% in nondiabetics). Nondiabetic patients had a higher rate of nodal downstaging although not statistically significant (67% versus 27%, P = 0.80). While none of the diabetics patients achieved a pathologic complete response (pCR), 23% (21/93) of the nondiabetics did (P = 0.039). Local progression rates were higher in the diabetic group (24% versus 5%, P = 0.046).

CONCLUSION

Our study shows that neoadjuvant chemoradiotherapy in rectal cancer is less effective in diabetic patients than in nondiabetics. While minimal differences are found in the rate of downstaging, the rate of achieving a complete pathologic response was significantly higher in nondiabetic patients, and in fact was not seen in any of our diabetic patients. This may explain the poorer outcomes seen in diabetic patients with rectal cancer.

In Vivo Intraoperative Radiotherapy: A Novel Approach to Radiotherapy for Early Stage Breast Cancer

INTRODUCTION

Intraoperative radiotherapy (IORT) has the potential to eliminate the access problems associated with standard 6-week post-operative external beam radiotherapy for patients with breast cancer. However, accurate delivery of the IORT dose for breast cancer has been problematic due to difficulty estimating the tumor bed after tumor removal and tissue re-approximation. We are investigating the feasibility of partial breast irradiation using a single fraction of IORT delivered to the tumor in vivo prior to surgical resection.

METHODS

In a trial, approved by the University of North Carolina School of Medicine Institutional Review Board, patients > or =55 years old with infiltrating ductal carcinoma without an extensive intraductal component with an overall tumor size < or =3.0 cm receive a single dose of IORT in place of standard post-operative radiotherapy.

RESULTS

All patients undergo preoperative ultrasonography to define the target volume. In a standard operating room, the tumor is exposed through a standard partial mastectomy incision. IORT is then delivered using a mobile, self-shielded, magnetron-driven X-band linear accelerator (Intraop Corp, Santa Clara, CA, USA). 15 Gy is delivered to the 90% isodose line covering the tumor with a 1 cm margin anterior-posterior and 2 cm margins laterally. After IORT, partial mastectomy is performed in the usual manner.

CONCLUSIONS

IORT for breast cancer, delivered to the exposed tumor in vivo, is feasible and allows accurate estimation of the tumor bed. Further follow-up is ongoing to determine the efficacy of this approach.

In vitro-in vivo correlation of hepatobiliary drug clearance in humans

The biliary clearance (Cl(biliary)) of three compounds was estimated using sandwich-cultured human hepatocytes (SCHH) and compared with Cl(biliary) values measured in vivo. Tc-99m sestamibi (MIBI) Cl(biliary) was determined in seven healthy volunteers using an oroenteric catheter to aspirate duodenal secretions, and gamma scintigraphy to determine gallbladder contraction; this technique was used previously to determine Tc-99m mebrofenin (MEB) and piperacillin (PIP) in vivo Cl(biliary). In vitro Cl(biliary) of MEB, MIBI, and PIP was quantified in SCHH as the ratio of mass excreted into bile canaliculi and area under the blood concentration-time curve (AUC) in medium. MIBI Cl(biliary) in vivo was 5.5+/-1.2 mL/min/kg (mean+/-SD). The rank order of Cl(biliary) predicted from SCHH corresponded well with the in vivo Cl(biliary) values in mL/min/kg for MEB (7.44 vs 16.1), MIBI (1.20 vs 5.51), and PIP (0.028 vs 0.032). In conclusion, the methods developed allowed for reproducible quantification of Cl(biliary) of drugs in healthy humans and prediction of Cl(biliary) from in vitro data.

Complications associated with neoadjuvant radiotherapy in the multidisciplinary treatment of retroperitoneal sarcomas

INTRODUCTION

Retroperitoneal sarcomas (RPS) remain a therapeutic challenge due to high local recurrence rates. Preoperative RT offers theoretical advantages in the multidisciplinary care of RPS. The purpose of our study was to evaluate our experience using preoperative radiotherapy (PRT) in the treatment of RPS.

METHODS

This is a single-institution review of patients with RPS treated with PRT from 1994 until 2004. Three radiation oncologists and four surgical oncologists were involved. Medical records, tumor registries, and death records were reviewed.

RESULTS

Fourteen patients were included; nine were treated for primary presentation and five for recurrent disease. Histologic grade was grade I (n = 3), grade II (n = 3), and grade III (n = 8). Five patients received additional IORT. Radiotherapy complications were generally mild, including nausea (n = 3), diarrhea (n = 1), dehydration (n = 1), anemia (n = 1), and skin changes (n = 1); one required early cessation due to nausea. Thirteen patients had gross negative margins; while 7/13 had negative microscopic margins. Operative complications included anastomotic bleeding (n = 1), fluid collections (n = 2), ileus (n = 3), ascites (n = 2), temporary leg weakness (n = 1), and uncomplicated wound infections (n = 2). In patients with R0 or R1 resections, one and two year local control rates were 64 and 50%. Overall survival for all patients was 90% at 1 year and 74% at 2 years with median survival of 21 months.

CONCLUSION

PRT and IORT can be administered effectively in carefully selected patients with resectable RPS. Larger multi-center studies are needed to delineate the role of PRT and IORT to improve local recurrence and survival rates in the treatment of RPS.

Experienced radio-guided surgery teams can successfully perform minimally invasive radio-guided parathyroidectomy without intraoperative parathyroid hormone assays

Minimally invasive parathyroidectomy is an accepted treatment option for primary hyperparathyroidism. The need for intraoperative parathyroid hormone assays (iPTH) to confirm adenoma removal remains controversial. We studied minimally invasive radio-guided parathyroidectomy (MIRP) performed using preoperative sestamibi localization studies, intraoperative gamma detection probe, and the selective use of frozen section pathology without the use of iPTH. This is a single institution review of patients with primary hyperparathyroidism treated with MIRP by surgeons experienced in radio-guided surgery between October 1, 1998 and July 15, 2005. Information was obtained by reviewing computer medical records as well as contacting primary care physicians. Factors evaluated included laboratory values, pathology results, and evidence of recurrence. One hundred forty patients were included with a median preoperative calcium level of 11.3 mg/dL (range, 9.6-17) and a PTH level of 147 pg/mL (range, 19-5042). The median postoperative calcium level was 9.3 mg/dL. All patients were initially eucalcemic postoperatively except for one who had normal parathyroid levels. However, five (4%) patients required re-exploration for various reasons. Of the failures, one was secondary to the development of secondary hyperparathyroidism, and therefore would not have benefited from iPTH, one had thyroid tissue removed at the first operation, and three developed evidence of a second adenoma. One of these three patients had a drop in PTH level from 1558 pg/mL preoperatively to 64 pg/mL on postoperative Day 1, indicating that iPTH would not have prevented this failure. Thus, only three (2.1%) patients could have potentially benefited from the use of iPTH. MIRP was successful in 96 per cent of patients using a combination of preoperative sestamibi scans, intraoperative localization with a gamma probe, and the selective use of frozen pathology. This correlates with reported success rates of 95 per cent to 100 per cent using iPTH. We conclude that minimally invasive parathyroidectomy can be successfully performed without using iPTH assays.

Experienced Radio-Guided Surgery Teams Can Successfully Perform Minimally Invasive Radio-Guided Parathyroidectomy without Intraoperative Parathyroid Hormone Assays

Minimally invasive parathyroidectomy is an accepted treatment option for primary hyperpara-thyroidism. The need for intraoperative parathyroid hormone assays (iPTH) to confirm adenoma removal remains controversial. We studied minimally invasive radio-guided parathyroidectomy (MIRP) performed using preoperative sestamibi localization studies, intraoperative gamma detection probe, and the selective use of frozen section pathology without the use of iPTH. This is a single institution review of patients with primary hyperparathyroidism treated with MIRP by surgeons experienced in radio-guided surgery between October 1, 1998 and July 15, 2005. Information was obtained by reviewing computer medical records as well as contacting primary care physicians. Factors evaluated included laboratory values, pathology results, and evidence of recurrence. One hundred forty patients were included with a median preoperative calcium level of 11.3 mg/dL (range, 9.6–17) and a PTH level of 147 pg/mL (range, 19–5042). The median postoperative calcium level was 9.3 mg/dL. All patients were initially eucalcemic postoperatively except for one who had normal parathyroid levels. However, five (4%) patients required re-exploration for various reasons. Of the failures, one was secondary to the development of secondary hyperparathyroidism, and therefore would not have benefited from iPTH, one had thyroid tissue removed at the first operation, and three developed evidence of a second adenoma. One of these three patients had a drop in PTH level from 1558 pg/mL preoperatively to 64 pg/mL on postoperative Day 1, indicating that iPTH would not have prevented this failure. Thus, only three (2.1%) patients could have potentially benefited from the use of iPTH. MIRP was successful in 96 per cent of patients using a combination of preoperative sestamibi scans, intraoperative localization with a gamma probe, and the selective use of frozen pathology. This correlates with reported success rates of 95 per cent to 100 per cent using iPTH. We conclude that minimally invasive parathyroidectomy can be successfully performed without using iPTH assays.

Axillary lymph node count is lower after neoadjuvant chemotherapy

BACKGROUND

Retrieval of fewer than 10 lymph nodes at axillary dissection (ALND) for breast cancer can represent anatomic variation or inadequate dissection. We postulated that despite aggressive ALND, a lower lymph node count is more frequent after neoadjuvant chemotherapy.

METHODS

Patients who received neoadjuvant chemotherapy followed by ALND were compared with patients who received surgery first. All patients received a level I and II ALND at a single institution by one of the breast surgeons. The number of nodes retrieved at ALND was dichotomized into categories (< 10 and > or = 10), and compared using Fisher exact test.

RESULTS

A total of 143 neoadjuvant and 170 surgery-first patients were studied. Patients treated with neoadjuvant chemotherapy were significantly more likely to have fewer than 10 lymph nodes retrieved at ALND than were the surgery-first patients (19/143 or 13% vs. 6/170 or 4%, P = .003).

CONCLUSIONS

A low lymph node count is more common in patients after treatment with neoadjuvant chemotherapy and should not be assumed to represent an incomplete ALND.

Successful minimally invasive parathyroidectomy for primary hyperparathyroidism without using intraoperative parathyroid hormone assays

BACKGROUND

The need for intraoperative parathyroid hormone (iPTH) assays in minimally invasive parathyroidectomy (MIP) remains controversial. We report the results of MIP performed without the use of iPTH assays.

METHODS

This was a single-institution retrospective review of patients with primary hyperparathyroidism treated with MIP between October 1, 1998, and December 31, 2002.

RESULTS

Seventy-seven patients were studied. The mean preoperative calcium level was 11.4 mg/dL. All patients had a normal calcium level postoperatively (range, 7.4-10.2 mg/dL, mean, 9.1 mg/dL). Three patients (4%) required re-exploration for various reasons including the development of a second adenoma, secondary hyperparathyroidism, and discordant pathology. All 3 patients initially were eucalcemic.

CONCLUSIONS

Our success rate of 96% using a combination of preoperative sestamibi scans, intraoperative gamma probe localization, and selective frozen pathology is consistent with the published success rates using iPTH assays of 95% to 100%. We conclude that MIP can be performed successfully without using iPTH assays.

Size of residual lymph node metastasis after neoadjuvant chemotherapy in locally advanced breast cancer patients is prognostic

BACKGROUND

The prognostic significance of micrometastasis after neoadjuvant chemotherapy for locally advanced breast cancer is unknown. We examined the residual lymph node metastasis size in patients after treatment with neoadjuvant chemotherapy to determine the relevance of metastasis size on outcome.

METHODS

Stage II/III breast cancer patients treated with neoadjuvant chemotherapy at our institution from 1991 to 2002 were included. We examined the relationship of postneoadjuvant chemotherapy lymph node metastasis size and number with distant disease-free survival (DDFS) and overall survival (OS).

RESULTS

In 122 patients with a median follow-up of 5.4 years, we found not only that patients with an increasing number of residual positive nodes had progressively worse DDFS and OS (P < .0001 for both) compared with patients with negative nodes, but also that the size of the largest lymph node metastasis was associated with worse DDFS and OS (P < .0001 for both) in both univariate and multivariate analysis. Compared with negative nodes, even lymph node micrometastasis (<2 mm) was associated with worsened DDFS and OS (adjusted P = .02 and P = .005, respectively).

CONCLUSIONS

Residual micrometastatic disease in the axillary lymph nodes after neoadjuvant chemotherapy is predictive of worse prognosis than negative nodes. In this study, the lymph node metastasis size and the number of involved lymph nodes were independent powerful predictors of DDFS and OS.

Staged sentinel lymph node biopsy before mastectomy facilitates surgical planning for breast cancer patients

BACKGROUND

In patients with breast cancer who choose mastectomy with immediate reconstruction, the sentinel lymph node (SLN) status on permanent histology may complicate treatment if a metastasis is found. The purpose of this study was to determine how performing an SLN biopsy (SLNB) before the definitive operation would influence subsequent surgical procedures.

METHODS

Our SLN database was searched for patients who underwent staged SLNB with subsequent mastectomy between 2001 and 2004.

RESULTS

Twenty-five patients with 27 breast cancers underwent SLNB before mastectomy. Of them, 9 of 27 (33%) were node positive. All 9 patients underwent modified radical mastectomy. Three node-positive patients did not undergo immediate reconstruction. Of the remaining 6 node-positive patients, 5 underwent reconstruction with autologous tissue rather than a tissue expander. In contrast, 6 of 16 (37%) node-negative patients underwent reconstruction with a tissue expander.

CONCLUSIONS

Staged SLNB assists in selecting the appropriate operation in patients who are considering immediate reconstruction.

Microsatellite instability testing in colorectal carcinoma: choice of markers affects sensitivity of detection of mismatch repair-deficient tumors

PURPOSE

Microsatellite instability (MSI) is found in 10% to 15% of sporadic colorectal tumors and is usually caused by defects in DNA mismatch repair (MMR). In 1997, a panel of microsatellite markers including mononucleotide and dinucleotide repeats was recommended by a National Cancer Institute workshop on MSI. We investigated the relationship between instability of these markers and MMR protein expression in a cohort of sporadic colorectal cancer patients.

EXPERIMENTAL DESIGN

Paraffin sections of normal and tumor tissue from 262 colorectal cancer patients were examined for MSI status by PCR amplification and for MMR protein expression using antibodies against hMLH1, hPMS2, hMSH2, and hMSH6.

RESULTS

Twenty-six (10%) of the patients studied had tumors with a high level of MSI (MSI-H). The frequencies of MSI were the same in African-American and Caucasian patients. Each of the MSI-H tumors had mutations in both mononucleotide and dinucleotide repeats and had loss of MMR protein expression, as did two tumors that had low levels of MSI (MSI-L). These two MSI-L tumors exhibited mutations in mononucleotide repeats only, whereas eight of the other nine MSI-L tumors had mutations in just a single dinucleotide repeat. There was not a statistically significant difference in outcomes between patients whose tumors were MMR-positive or MMR-negative, although there was a slight trend toward improved survival among those with MMR-deficient tumors.

CONCLUSIONS

The choice of microsatellite markers is important for MSI testing. Examination of mononucleotide repeats is sufficient for detection of tumors with MMR defects, whereas instability only in dinucleotides is characteristic of MSI-L/MMR-positive tumors.

High-resolution axillary ultrasound is a poor prognostic test for determining pathologic lymph node status in patients undergoing neoadjuvant chemotherapy for locally advanced breast cancer

BACKGROUND

The purpose of this study was to evaluate the efficacy of high-resolution axillary ultrasound in detecting axillary lymph node metastases after neoadjuvant chemotherapy in patients with locally advanced breast cancer.

METHODS

Fifty-three patients with stage II or III breast cancer undergoing neoadjuvant chemotherapy who had a physical examination, high-resolution axillary ultrasound, and axillary lymph node dissection from January 1999 to September 2003 were included in this study.

RESULTS

The positive predictive value of the postchemotherapy ultrasound for predicting pathologic nodal involvement was 83%, but the negative predictive value was only 52%. Postchemotherapy physical examination was also poor at predicting pathologic nodal involvement with a positive predictive value of 93% and a negative predictive value of only 58%.

CONCLUSIONS

A negative post-neoadjuvant chemotherapy high-resolution axillary ultrasound or physical examination does not predict pathologic node status, and this test has limited value in this setting.

Extracapsular extension of the sentinel lymph node metastasis: a predictor of nonsentinel node tumor burden

OBJECTIVE

To identify predictors of nonsentinel node (NSN) tumor involvement in patients with a tumor-involved sentinel node (SN).

SUMMARY BACKGROUND DATA

For many breast cancer patients who undergo intraoperative lymphatic mapping and sentinel lymphadenectomy (LM/SL), the SN is the only tumor-involved axillary node. Associations between NSN tumor involvement and several clinical and histopathologic factors have been identified. The authors hypothesize that extracapsular extension (ECE) of the SN metastasis is highly predictive of NSN tumor involvement.

METHODS

Between May 1998 and December 2001, 260 patients (263 cases) with clinical T1 or T2 (<5.0 cm) breast cancer underwent LM/SL at the University of North Carolina, using a combined blue dye and technetium sulfur colloid technique. In all cases with a tumor-involved SN, axillary lymph node dissection (ALND) was recommended. Statistical analysis, with Pearson chi-square tests, Fisher exact test, and multiple logistic regression, was performed.

RESULTS

The SN contained tumor in 74 (28.1%) cases. ALND was performed in 70 of the 74 cases. ECE of the SN metastasis was present in 18 (25.7%) of the 70 cases. Patients with ECE of the SN metastasis were more likely to have NSN tumor involvement and had a greater total number of tumor-involved nodes than patients without ECE of the SN metastasis. Increasing size of the SN metastasis and increasing size of the primary tumor, examined as continuous variables, were associated with an increased likelihood of NSN tumor involvement on univariate analysis. However, only ECE of the SN metastasis was associated with NSN tumor involvement on multivariate analysis.

CONCLUSIONS

ECE of the SN metastasis is a strong predictor of NSN tumor involvement. All patients with ECE of the SN metastasis should undergo mandatory completion ALND.

Human epidermal receptor-2 expression in prostate cancer

PURPOSE

Efforts to conclusively establish that human epidermal receptor (HER)-2 overexpression is important to androgen-dependent carcinoma of the prostate (AD-CaP) or to progression to androgen independence (AI-CaP) have failed because of variability in tissue procurement, antibodies, immunostaining procedures, and assessment methods. However, because some in vitro and animal model data correlate HER-2 overexpression with progression to androgen independence, trials of agents that target the HER-2 receptor are under way. To clarify human tumor findings, we studied HER-2 expression at the gene (DNA), mRNA, and protein levels in well-characterized CaP specimens.

EXPERIMENTAL DESIGN

Fifty AD-CaP and 25 AI-CaP specimens from similar numbers of Caucasian and African Americans were immunostained for HER-2 receptor. HER-2 mRNA levels were measured using real-time fluorescence quantitative PCR in patients for whom frozen specimens were available. HER-2 amplification was evaluated using fluorescent in situ hybridization.

RESULTS

HER-2 receptor immunostained in 52% of androgen-dependent and one (4%) androgen-independent tumor. HER-2 immunostaining was not related to age, race, serum prostate-specific antigen levels, or pathologic stage and Gleason grade. HER-2 overexpression was not detected in AI-CaP at the mRNA or gene level. Mean HER-2 mRNA expression was higher (P < 0.05) in AD-CaP than AI-CaP (22,080 versus 15,496 HER-2 copies). HER-2 was not amplified in any of 20 AD-CaP or 19 AI-CaP specimens.

CONCLUSIONS

HER-2 protein and message overexpression and HER-2 amplification were not found in AI-CaP.

The EGF receptor family--multiple roles in proliferation, differentiation, and neoplasia with an emphasis on HER4

The EGF Receptor (EGFR), the first transmembrane receptor tyrosine kinase cloned and sequenced, and its closely related family members HER2, HER3, and HER4, play myriad roles in mammalian growth and development. Receptor activation involves ligand binding to separate receptors followed by formation of active dimers. These receptors can signal as homodimers or they can subtly alter signaling output by heterodimerizing with other family members. Adding complexity, these receptors with varying specificity bind at least 10 ligands from two ligand families, the EGF and neuregulin/heregulin families. This signaling system's impact on human neoplasia is underscored by the following: i.) EGFR is overexpressed or activated by autocrine or paracrine growth factor loops in at least 50% of epithelial malignancies; ii.) HER2 is amplified and dramatically overexpressed in approximately 20%-25% or breast cancers; iii) HER3 and HER4 are variably expressed in breast and other cancers. Overexpression and/or activation of EGFR, HER2 and HER3 has been correlated with poor tumor prognosis; antibody and small molecule inhibitors of their activity are being tested as therapy in cancer patients. However, the signaling complexity engendered by four interacting receptors and ten ligands makes it difficult to definitively measure receptor signaling output in human tumors and even makes mechanistic studies of the family's role in normal physiology and neoplastic transformation a challenge. In spite of the literature's emphasis on growth control, activation by some EGF receptor family member ligands can produce tumor cell differentiation, characterized by growth cessation and differentiation gene product synthesis. The present work delineates a role for HER4 in breast cancer cell differentiation and demonstrates that HER4 is both necessary and sufficient to produce an anti-proliferative signal. These

Long-term outcome of neoadjuvant therapy for locally advanced breast carcinoma: effective clinical downstaging allows breast preservation and predicts outstanding local control and survival

OBJECTIVE

To review the long-term follow-up data from the authors' institutional experience of 62 patients with locally advanced breast cancer (LABC) treated with a uniform multimodality regimen. The authors determined the rate of breast preservation, the disease-free and overall survival, and the factors associated with locoregional and distant recurrent disease.

SUMMARY BACKGROUND DATA

It remains a challenge to achieve local and distant control of LABC. Over the last decade, preoperative or neoadjuvant chemotherapy has emerged as the standard of care for these patients. Successful tumor downstaging has been associated with increased rates of breast-conserving therapy (BCT), but the overall effect on long-term survival remains to be seen.

METHODS

This study examines a cohort of 62 patients with LABC treated at the authors' institution from 1992 to 1998. The uniform treatment regimen consisted of neoadjuvant doxorubicin (Adriamycin), followed by operation (BCT if sufficient clinical downstaging), followed by non-cross-resistant cyclophosphamide/methotrexate/5-fluorouracil, followed by radiation therapy. Treatment was both dose-intensive and time-intensive, with a total treatment time of 32 to 35 weeks.

RESULTS

In this patient population, the median age was 44 years, with approximately two thirds white patients and one third African American. Eighty-two percent of patients were clinical stage III at presentation, 13 patients had T4d inflammatory cancers, and 3 patients were stage IV at diagnosis. Eighty-four percent of patients demonstrated a significant clinical response to doxorubicin. Twenty-eight patients had sufficient clinical downstaging to attempt BCT, and 22 (45%) of 49 noninflammatory patients underwent successful BCT. Pathologic complete response was seen in 15% of patients. Median follow-up for the cohort was 70 months. The local recurrence rate was 14%, including two ipsilateral breast tumor recurrences (10%) in the BCT patients. Seven (12%) patients developed a new primary cancer in the contralateral breast. Distant metastases occurred in 18 (31%) patients, and the 5-year overall survival rate for the cohort was 76%. Furthermore, in the patients who underwent an attempt at BCT, the survival rate was 96% at 5 years.

CONCLUSIONS

Dose-intensive and time-intensive multimodality neoadjuvant therapy was successfully administered to a mixed racial group over shortened times. Patients who had sufficient clinical downstaging to allow BCT have the best long-term outcome. Patients who required mastectomy are at a higher risk of relapse, as well as the development of new contralateral cancers, yet have 5-year survival rates of over 50%.

Cytokeratin immunohistochemical validation of the sentinel node hypothesis in patients with breast cancer

No standard method for handling and histopathologic examination of the sentinel node (SN) exists. We hypothesized that a focused examination of all nodes with serial sectioning and cytokeratin immunohistochemical staining would confirm the SN as the node most likely to harbor metastasis. Intraoperative lymphatic mapping and sentinel lymphadenectomy using blue dye and (99m)technetium-labeled sulfur colloid were performed. All nodes were stained with H&E. All tumor-free nodes underwent additional sectioning and staining with H&E and an immunohistochemical stain. Routine H&E examination detected SN metastases in 27.6% of cases. Occult SN metastases were identified in 12.7% of cases. None of the 724 non-SNs examined contained occult metastases. The SN false-negative rate was zero. This study confirms histopathologically that the SN has biologic significance as the axillary node most likely to harbor metastatic tumor Standardization of the handling, sectioning, and staining of the SN is necessary as lymphatic mapping and sentinel lymphadenectomy become integrated into the care of patients with breast cancer

Expression and regulation of nonsteroidal anti-inflammatory drug-activated gene (NAG-1) in human and mouse tissue

BACKGROUND & AIMS

Nonsteroidal anti-inflammatory drugs (NSAIDs) induce NSAID-activated gene 1 (NAG-1), which has proapoptotic and antitumorigenic activities. However, NAG-1 expression and its relationship with apoptosis in human and mouse intestinal tract have not been determined.

METHODS

NAG-1 expression in human and mouse tissue was determined by immunohistochemistry, and apoptosis was estimated by in situ apoptosis detection. Apoptosis in NAG-1 overexpressing HCT-116 cells was examined with flow cytometry after cell sorting by green fluorescence protein. NAG-1 regulation in mouse cells was examined by Northern blot analysis, comparing sulindac-treated and nontreated mice.

RESULTS

Apoptosis was higher in NAG-1 overexpressing cells compared with controls. Human NAG-1 protein was localized to the colonic surface epithelium where cells undergo apoptosis, and higher expression was observed in the normal surface epithelium than in most of the tumors. This localization and lower expression in tumors was similar to that in the Min mouse, in which NSAIDs were also shown to regulate the expression of NAG-1 in mouse cells. Sulindac treatment of mice increased the NAG-1 expression in the colon and liver.

CONCLUSIONS

Based on these results, we propose that NAG-1 acts as a mediator of apoptosis in intestinal cells and may contribute to cancer chemoprevention by NSAIDs.

Dysregulation of annexin I protein expression in high-grade prostatic intraepithelial neoplasia and prostate cancer

PURPOSE

To determine expression levels of annexin I (lipocortin I) in patient-matched benign prostatic epithelium (BPE), high-grade prostatic intraepithelial neoplasia (HGPIN), and prostate cancer (CaP). EXPERIMETNAL DESIGN: Annexin I protein expression was examined with a standard immunohistochemical protocol in 69 radical prostatectomy specimens, 45 of which also contained HGPIN. Immunostained sections were scored visually by a genitourinary pathologist and mean optical density was measured with digital image analysis. Real-time fluorescence quantitative PCR was used to measure expression levels of annexin I mRNA in patient-matched CaP and BPE from 14 snap-frozen, radical prostatectomy specimens.

RESULTS

Annexin I protein expression was reduced in 91% (41/45) of HGPIN lesions and 94% (65/69) of invasive CaP compared with BPE in the same histological section when assessed visually. Mean absorbance was reduced significantly (P < 0.05) in 97.7% (44/45) of HGPIN lesions and 98.5% (68/69) of CaP glands compared with BPE. In 79% of cases (11/14; P < 0.05), mRNA expression was reduced in CaP as compared with patient-matched BPE. Annexin I mRNA and protein expression levels did not correlate with Gleason grade, pathological stage, or race.

CONCLUSIONS

Down-regulation of annexin I protein expression is a common finding in HGPIN and CaP, suggesting that annexin I dysregulation may be an important early event in CaP initiation. Because mRNA levels are reduced in a high proportion of cases, one likely mechanism for annexin I dysregulation occurs at the level of gene transcription. Results of these studies support a valuable role for a molecular profiling approach to CaP research.

Peritoneovenous shunting for nongynecologic malignant ascites

BACKGROUND

The development of malignant ascites has been associated with a poor prognosis. Previous reports have documented high morbidity rates associated with placement of palliative peritoneovenous shunts (PVS). Most study series have included gynecologic malignancies in their analysis, and wide variations in survival time have been reported. Reported data from nongynecologic malignancies and identification of preoperative factors associated with improved outcome were the concerns of the current study, which attempted to identify patients with malignant ascites who might have benefitted from PVS.

METHODS

A retrospective chart review was performed and data including age, gender, weight, preoperative laboratory values, cytology on peritoneal fluid aspirates, and complications within 30 days of the operative procedure were obtained and recorded. Discharge date and follow-up status were obtained for all patients. Statistical analysis was done for categorical values by comparing survival times from date of procedure with follow-up times using the log rank test. Significance for numeric values was determined with Cox regression analysis. Multivariate analysis using Cox regression was performed for those values found to be significant on univariate analysis.

RESULTS

Fifty- five patients who had undergone PVS from 1980-1996 for ascites on the Gastric and Mixed Tumor service at the Memorial Sloan-Kettering Cancer Center were identified. Two patients with benign disease and two patients with ovarian malignancies were excluded. The remaining 51 patients underwent placement of 53 PVSs for palliation. Median survival time for the entire group was 52 days. Univariate analysis identified preoperative blood urea nitrogen (BUN), creatinine (Cr), BUN to Cr ratio, and diagnosis as significant factors. Preoperative BUN emerged as an independent predictor of survival by multivariate analysis, and those patients who had a BUN value of < = 17 demonstrated a survival advantage over those with a BUN of > 17. The assessable palliation factors were hospital discharge (80% of patients) and weight loss after shunting (68% of patients lost > 1 kg). Ninety-six percent of patients (24 of 25) with a preoperative BUN of < or = 17 were discharged.

CONCLUSIONS

The development of nongynecologic malignant ascites is an end stage event for most patients. The placement of PVS for those patients with nongastrointestinal tumor etiologies, a BUN of < 17, a Cr of < or = 1.1, and a BUN to Cr ratio of < 19 yielded the best results. In the current study, palliation was difficult to assess accurately, although most patients were discharged or lost > 1kg of weight after shunting.

Expression of 15-lipoxygenase-1 in human colorectal cancer

Recently, we reported the induction of reticulocyte type 15-lipoxygenase (15-Lox-1) in a human colorectal carcinoma cell line that had been stimulated by butyrate to undergo apoptosis and cell differentiation (H. Kamitani et al., J. Biol. Chem., 273: 21569-21577, 1998). To determine if 15-Lox-1 is expressed in human colorectal cancer tissue, 21 matched pairs of colorectal tumor and adjacent normal tissue were examined by immunoblot analysis using specific antibodies for human 15-Lox-1, prostaglandin H synthase (also called cyclooxygenase, Cox)-1 and Cox-2. Eighteen of the 21 were found to have 15-Lox-1 in both tumor tissue and matched adjacent normal tissue, with the 15-Lox-1 expression being significantly higher in most of the tumor tissue. The expression of Cox-2 was also elevated in most tumors, whereas Cox-1 was frequently expressed at lower levels in the tumor tissue than in the paired normal tissue. Reverse-phase high-performance liquid chromatography analysis of arachidonate metabolites, formed on incubation of arachidonic acid with a crude enzyme preparation from the colon samples, revealed the formation of 15-hydroxy-5Z,8Z,11Z,13E-eicosatetraenoic acid with a much lower level of 12-hydroxy-5Z,8Z,10E,14Z-eicosatetraenoic acid (15-hydroxy-5Z,8Z,11Z,13E-eicosatetraenoic acid:12-hydroxy-5Z,8Z,10E,14Z-eicosatetraenoic acid, 6.5:1) which also indicate the presence of 15-Lox-1. Furthermore, reverse transcription-PCR with primers specific for human 15-Lox-1 or 15-Lox-2 cDNA indicated that 15-Lox-1 mRNA was present in the colorectal tumors. The sequence of the PCR product was identical to the human 15-Lox-1. Immunohistochemical studies showed 15-Lox-1 localization in the glandular epithelium of human colorectal tumor tissue. These results suggest that 15-Lox-1 is highly expressed in human colorectal cancer epithelial cells and that its expression may have a role in colorectal carcinogenesis.

Beyond anatomy: MR imaging as a molecular diagnostic tool

Technical advances in software and hardware make MR imaging competitive with CAT scanning as an anatomic imaging tool. Although anatomic relationships remain important, increased understanding of cell structure and function is rapidly moving us toward diagnosis and treatment at the cellular level. By virtue of its reliance on nuclear magnetic spin moment, MR imaging is responsive to real time physico-chemical characteristics of cells and tissues being imaged. This intrinsic advantage of MR imaging is being rapidly developed through the use of targeted imaging agents and magnetic resonance spectroscopy. Imaging agents that target specific cell populations have been prepared by using monoclonal antibodies, liposomes, and short peptides bound to chelates containing paramagnetic atoms. Using magnetic resonance spectroscopy, the chemical composition of tumors can be analyzed and compared with normal tissues in vivo and in vitro. Areas of possible clinical usefulness for magnetic spectral analysis include: (1) in vitro or in vivo characterization of lesions as benign or malignant, (2) differentiation between in situ and invasive carcinomas, (3) determination of responsiveness to specific chemotherapeutic regimens before their institution, (4) study of in vivo drug metabolism by neoplasms, and (5) assessment of response to therapy and of residual disease at the completion of therapy. Early experiences in these parallel fields show great promise, with widespread clinical applications expected in the near future.

Cholangiocarcinoma: spectrum of appearances on MR images using current techniques

This study describes the spectrum of appearances of cholangiocarcinoma on magnetic resonance (MR) sequences, including gadolinium-enhanced, fat-suppressed spoiled gradient echo images and MR cholangiography. Fifteen patients were included in the study. Histologic diagnosis was established in 11 patients by surgical resection (6 patients), percutaneous biopsy (4 patients), and open liver biopsy (1 patient). The final diagnosis was determined by correlation of the MR findings with cholangiographic studies and laboratory studies in 4 patients. MR studies were performed at 1.5 T, and the following sequences were obtained: T1-weighted spoiled gradient echo (SGE), T1-weighted fat-suppressed spin echo or SGE, T2-weighted fat-suppressed conventional or turbo spin echo, MR cholangiography, and gadolinium-enhanced T1-weighted fat-suppressed SGE images. The following determinations were made: tumor location, tumor extent, ductal dilatation, ductal wall thickness, signal intensity, enhancement pattern, and associated findings. Mass-like neoplasms were peripheral (6 patients), hilar (1 patient), and extrahepatic (2 patients). Circumferential tumors were hilar (2 patients) and extrahepatic (4 patients). All peripheral tumors were multifocal. Mass-like tumors were well-defined, rounded, and ranged from 1 to 14 cm in diameter. Circumferential tumors had less well-defined margins and measured from 3 to 15 mm in thickness. All mass-like tumors were moderately hypointense on T1-weighted images and mildly to moderately hyperintense on T2-weighted images. The circumferential tumors were iso- to moderately hypointense on T1-weighted images and iso- to mildly hyperintense on T2-weighted images. Mass-like tumors were generally well shown on non-contrast and immediate gadolinium-enhanced images, whereas circumferential tumors were poorly seen on non-contrast images and best shown on gadolinium-enhanced T1-weighted fat-suppressed images. The degree of enhancement ranged from minimal to intense on immediate gadolinium-enhanced images, with all tumors becoming more homogeneous in signal intensity on images obtained between 1 and 5 min following contrast administration. Tumor-containing lymph nodes greater than or equal to 1 cm in diameter were demonstrated in 11 out of 15 patients (73.3%). These were best shown on T2-weighted fat-suppressed images and gadolinium-enhanced fat-suppressed SGE images. MR cholangiography demonstrated the level of obstruction and degree of dilatation of the proximal biliary system in 5 out of 6 patients who underwent MR cholangiography. The spectrum of appearances of cholangiocarcinoma is demonstrable on MR images. Mass-like tumors are well shown on both pre- and post-gadolinium sequences. Circumferential tumors may cause minimally increased duct wall thickness and are most clearly shown on gadolinium-enhanced fat-suppressed SGE images obtained 1 to 5 min following gadolinium administration.

Metastatic gastric leiomyoblastoma: a case report

Gastric leiomyoblastoma is a rare entity. In this report, we describe the magnetic resonance (MR) appearance of a recurrent gastric leiomyoblastoma 14 years after initial presentation. This tumor was heterogeneous and moderately low signal intensity on T1-weighted images and heterogeneous and moderately high signal intensity on T2-weighted images. The tumor also contained foci of low signal intensity on the post gadolinium images, consistent with areas of necrosis. The mass enhanced mildly and increased in enhancement on the delayed images, consistent with a hypovascular mass. Multiple liver metastases were noted. Magnetic resonance findings were confirmed with surgical specimens.