A radiopaque polymer hydrogel used as a fiducial marker in gynecologic-cancer patients receiving brachytherapy.

PURPOSE: We assessed a novel Food and Drug Administration-approved hydrogel, synthesized as absorbable iodinated particles, in gynecologic-cancer patients undergoing computed tomography (CT) or magnetic resonance (MR) based brachytherapy after external beam radiation. METHODS AND MATERIALS: Nineteen patients underwent CT-guided (n = 13) or MR-guided (n = 6) brachytherapy for gynecologic cancers. Seventy-seven hydrogel injections were placed. The hydrogel material was injected into gross residual disease and/or key anatomic landmarks in amounts ranging from 0.1 to 0.4 mL. The visibility of the tracer was scored on CT and on MR images using a 5-point scoring scale. A Cohen's kappa statistic was calculated to assess interobserver agreement. To assess the unadjusted effects of baseline parameters on hydrogel visibility, we modeled visibility using a linear mixed-effect model. RESULTS: Injections were without complication. The kappa statistic was 0.77 (95% confidence interval [CI], 0.68-0.87). The volume of hydrogel injected was significantly associated with visibility on both CT (p = 0.032) and magnetic resonance imaging (p = 0.016). We analyzed visibility by location, controlling for amount. A 0.1-cc increase in volume injected was associated with increases of 0.54 (95% CI = 0.05-1.03) in the CT visibility score and 0.83 (95% CI = 0.17-1.49) in the MR visibility score. Injection of 0.4 cc or more was required for unequivocal visibility on CT or MR. No statistically significant correlation was found between tumor type, tumor location, or anatomical location of injection and visibility on either CT or magnetic resonance imaging. CONCLUSIONS: In this first report of an injectable radiopaque hydrogel, targets were visualized to assist with three-dimensional-based brachytherapy in gynecologic malignancies. This marker has potential for several applications, is easy to inject and visualize, and caused no acute complications.

Longitudinal study of acute haematologic toxicity in cervical cancer patients treated with chemoradiotherapy.

INTRODUCTION: Acute hematologic toxicity (HT) limits optimal delivery of concurrent chemoradiotherapy (CRT) for patients with pelvic malignancies. We tested the hypothesis that pelvic bone marrow (PBM) dose-volume metrics were associated with weekly reductions in peripheral blood cell counts in cervical cancer patients undergoing CRT. METHODS: We included 102 cervical cancer patients treated with concurrent cisplatin (40 mg/m(2) /week) and pelvic radiotherapy treated at three US centres. No patient received granulocyte-monocyte colony stimulating factor (GM-CSF) or platelet transfusions. Using linear-mixed effects modelling, we analysed weekly reductions in log-transformed peripheral blood cell counts as a function of time (weeks), mean PBM dose and the PBM volume receiving ≥10 Gy (V(10)), 20 Gy (V(20)), 30 Gy (V(30)) and 40 Gy (V(40)). RESULTS: Increases in mean PBM radiation dose, V(20), V(30) and V(40) were all significantly associated with a greater weekly reduction in white blood cell (WBC) and absolute neutrophil counts (ANCs). We estimated that with every 1 Gy increase in mean PBM dose, ln(ANC) was reduced by 9.6/µL per week (95% confidence interval, 1.9-17.3, P = 0.015). Subregion analysis also identified significant associations between weekly reductions in ln(WBC) and ln(ANC) within lumbosacral spine, ischium and proximal femora, as opposed to ilium. CONCLUSIONS: PBM radiation dose-volume metrics are significantly associated with weekly reductions in peripheral blood cell counts in cervical cancer patients undergoing CRT, particularly within the lower pelvis and lumbosacral spine.

Demystifying NUT midline carcinoma: radiologic and pathologic correlations of an aggressive malignancy.

OBJECTIVE: NUT midline carcinoma is a rare poorly differentiated aggressive subtype of squamous cell carcinoma. To date, fewer than 100 total cases have been reported. CONCLUSION: Given the rarity of this disease process and lack of pathognomonic imaging findings, a definitive diagnosis based solely on imaging findings alone is untenable. Select cases are used to emphasize the particularly infiltrative and aggressive nature of NUT midline carcinoma, which shows a complete disregard for normal tissue boundaries and rapid progression during brief intervals.

Dosimetric consequences of interobserver variability in delineating the organs at risk in gynecologic interstitial brachytherapy.

PURPOSE: To investigate the dosimetric variability associated with interobserver organ-at-risk delineation differences on computed tomography in patients undergoing gynecologic interstitial brachytherapy. METHODS AND MATERIALS: The rectum, bladder, and sigmoid of 14 patients treated with gynecologic interstitial brachytherapy were retrospectively contoured by 13 physicians. Geometric variability was calculated using κ statistics, conformity index (CIgen), and coefficient of variation (CV) of volumes contoured across physicians. Dosimetric variability of the single-fraction D0.1cc and D2cc was assessed through CV across physicians, and the standard deviation of the total EQD2 (equivalent dose in 2 Gy per fraction) brachytherapy dose (SD(TOT)) was calculated. RESULTS: The population mean ± 1 standard deviation of κ, CIgen, and volume CV were, respectively: 0.77 ± 0.06, 0.70 ± 0.08, and 20% ± 6% for bladder; 0.74 ± 06, 0.67 ± 0.08, and 20% ± 5% for rectum; and 0.33 ± 0.20, 0.26 ± 0.17, and 82% ± 42% for sigmoid. Dosimetric variability was as follows: for bladder, CV = 31% ± 19% (SD(TOT) = 72 ± 64 Gy) for D0.1cc and CV = 16% ± 10% (SD(TOT) = 9 ± 6 Gy) for D2cc; for rectum, CV = 11% ± 5% (SD(TOT) = 16 ± 17 Gy) for D0.1cc and CV = 7% ± 2% (SD(TOT) = 4 ± 3 Gy) for D2cc; for sigmoid, CV = 39% ± 28% (SD(TOT) = 12 ± 18 Gy) for D0.1cc and CV = 34% ± 19% (SD(TOT) = 4 ± 4 Gy) for D2cc. CONCLUSIONS: Delineation of bladder and rectum by 13 physicians demonstrated substantial geometric agreement and resulted in good dosimetric agreement for all dose-volume histogram parameters except bladder D0.1cc. Small delineation differences in high-dose regions by the posterior bladder wall may explain these results. The delineation of sigmoid showed fair geometric agreement. The higher dosimetric variability for sigmoid compared with rectum and bladder did not correlate with higher variability in the total brachytherapy dose but rather may be due to the sigmoid being positioned in low-dose regions in the cases analyzed in this study.

Clinical outcomes for gastric cancer following adjuvant chemoradiation utilizing intensity modulated versus three-dimensional conformal radiotherapy.

PURPOSE/OBJECTIVES: To determine if intensity modulated radiation therapy (IMRT) in the post-operative setting for gastric cancer was associated with reduced toxicity compared to 3D conformal radiation therapy (3DCRT). MATERIALS/METHODS: This retrospective study includes 24 patients with stage IB-IIIB gastric cancer consecutively treated from 2001-2010. All underwent surgery followed by adjuvant chemoradiation. Concurrent chemotherapy consisted of 5-FU/leucovorin (n = 21), epirubicin/cisplatin/5FU (n = 1), or none (n = 2). IMRT was utilized in 12 patients and 3DCRT in 12 patients. For both groups, the target volume included the tumor bed, anastomosis, gastric stump, and regional lymphatics. RESULTS: Median follow-up for the entire cohort was 19 months (range 0.4-8.5 years), and 49 months (0.5-8.5 years) in surviving patients. The 3DCRT group received a median dose of 45 Gy, and the IMRT group received a median dose of 50.4 Gy (p = 0.0004). For the entire cohort, 3-year overall survival (OS) was 40% and 3-year disease free survival (DFS) was 41%. OS and DFS did not differ significantly between the groups. Acute toxicity was similar. Between 3DCRT and IMRT groups, during radiotherapy, median weight lost (3.2 vs. 3.3 kg, respectively; p = 0.47) and median percent weight loss were similar (5.0% vs. 4.3%, respectively; p = 0.43). Acute grade 2 toxicity was experienced by 8 patients receiving 3DCRT and 11 receiving IMRT (p = 0.32); acute grade 3 toxicity occurred in 1 patient receiving 3DCRT and none receiving IMRT (p = 1.0). No patients in either cohort experienced late grade 3 toxicity, including renal or gastrointestinal toxicity. At last follow up, the median increase in creatinine was 0.1 mg/dL in the IMRT group and 0.1 mg/dL in the 3DCRT group (p = 0.78). CONCLUSION: This study demonstrates that adjuvant chemoradiation for gastric cancer with IMRT to 50.4 Gy was well-tolerated and compared similarly in toxicity with 3DCRT to 45 Gy.

The many faces of Behçet's disease.

A 23-year-old man with fevers, night sweats, lymphadenopathy, worsening vision, and aphthous ulcers was diagnosed with Behçet's disease. Multiple diagnostic imaging modalities were used to identify various multisystem complications associated with Behçet's disease including vascular thomboses, mediastinal fibrosis, chylothoraces, chylopericardium and coronary artery aneurysms.

An analysis of patient characteristics and clinical outcomes in primary pulmonary sarcoma.

INTRODUCTION: Literature concerning primary pulmonary sarcomas (PPS) is limited to small case series. This study examines, in a large cohort, the clinical characteristics and therapeutic strategies of PPS and their impact on overall survival (OS). METHODS: This was a retrospective analysis from the Surveillance, Epidemiology, and End Results database (1988-2008). Eligible patients had primary PPS and underwent local therapy. Survival estimates were obtained using the Kaplan-Meier method and the Cox regression model. OS of PPS patients were compared with a cohort of 10,909 patients with extremity soft-tissue sarcomas. RESULTS: The cohort included 365 PPS patients with a median follow-up of 21 months. Fifty-five percent of the patients had large tumors (>5 cm), 76% were high-grade, and 16% had node-positive disease. Seventy-five percent of the cohort underwent surgery alone, 14% underwent surgery and radiation therapy, and 11% underwent radiation therapy alone. Multivariate analysis showed reduced OS for patients with tumors more than 5 cm (hazard ratio [HR] 1.6, 95% confidence interval [CI] 1.25-2.19), high tumor grade (HR 3.1, 95% CI 1.26-3.62), and unresectable disease (HR 2.6, 95% CI 1.76-3.88. The 5-year OS for the cohort of pulmonary sarcomas versus sarcomas of the extremities was 35% versus 71% (p < 0.0001). CONCLUSION: This large study examining PPS patients reveals a high rate of nodal involvement and a markedly worse OS than patients with extremity soft-tissue sarcomas. Thus, given the poor overall prognosis, it is recommended that PPS patients undergo a thorough mediastinal nodal evaluation to rule out locoregional metastasis and proceed with aggressive treatment.

SMURF1 amplification promotes invasiveness in pancreatic cancer.

Pancreatic cancer is a deadly disease, and new therapeutic targets are urgently needed. We previously identified DNA amplification at 7q21-q22 in pancreatic cancer cell lines. Now, by high-resolution genomic profiling of human pancreatic cancer cell lines and human tumors (engrafted in immunodeficient mice to enrich the cancer epithelial fraction), we define a 325 Kb minimal amplicon spanning SMURF1, an E3 ubiquitin ligase and known negative regulator of transforming growth factor ß (TGFß) growth inhibitory signaling. SMURF1 amplification was confirmed in primary human pancreatic cancers by fluorescence in situ hybridization (FISH), where 4 of 95 cases (4.2%) exhibited amplification. By RNA interference (RNAi), knockdown of SMURF1 in a human pancreatic cancer line with focal amplification (AsPC-1) did not alter cell growth, but led to reduced cell invasion and anchorage-independent growth. Interestingly, this effect was not mediated through altered TGFß signaling, assayed by transcriptional reporter. Finally, overexpression of SMURF1 (but not a catalytic mutant) led to loss of contact inhibition in NIH-3T3 mouse embryo fibroblast cells. Together, these findings identify SMURF1 as an amplified oncogene driving multiple tumorigenic phenotypes in pancreatic cancer, and provide a new druggable target for molecularly directed therapy.

Array-based comparative genomic hybridization identifies localized DNA amplifications and homozygous deletions in pancreatic cancer.

Pancreatic cancer, the fourth leading cause of cancer death in the United States, is frequently associated with the amplification and deletion of specific oncogenes and tumor-suppressor genes (TSGs), respectively. To identify such novel alterations and to discover the underlying genes, we performed comparative genomic hybridization on a set of 22 human pancreatic cancer cell lines, using cDNA microarrays measuring approximately 26,000 human genes (thereby providing an average mapping resolution of <60 kb). To define the subset of amplified and deleted genes with correspondingly altered expression, we also profiled mRNA levels in parallel using the same cDNA microarray platform. In total, we identified 14 high-level amplifications (38-4934 kb in size) and 15 homozygous deletions (46-725 kb). We discovered novel localized amplicons, suggesting previously unrecognized candidate oncogenes at 6p21, 7q21 (SMURF1, TRRAP), 11q22 (BIRC2, BIRC3), 12p12, 14q24 (TGFB3), 17q12, and 19q13. Likewise, we identified novel polymerase chain reaction-validated homozygous deletions indicating new candidate TSGs at 6q25, 8p23, 8p22 (TUSC3), 9q33 (TNC, TNFSF15), 10q22, 10q24 (CHUK), 11p15 (DKK3), 16q23, 18q23, 21q22 (PRDM15, ANKRD3), and Xp11. Our findings suggest candidate genes and pathways, which may contribute to the development or progression of pancreatic cancer.