Evaluation of sexual function on a randomized trial of a prostate rectal spacer

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Background: The SpaceOAR phase 3 trial showed that a hydrogel spacer between the prostate and rectum decreased rectal dose and toxicity while improving bowel quality of life (QOL) after image guided prostate IMRT to 79.2 Gy. Here we evaluated dose to penile bulb as well as sexual function on this trial Methods: Sexual QOL was measured with the Expanded Prostate Cancer Index Composite (EPIC) by mean summary scores and the proportion of patients with a minimally important decline (MID) (11 points). Stratification was based on severe erectile dysfunction (ED)(EPIC < = 60) vs not. The single question on “Erections sufficient for intercourse over the preceding 4 weeks” was also evaluated. Results: Median Follow-up was 37 months with 63% of men evaluable at 3 years. With spacer the dose to the penile bulb was reduced for mean (21 vs 11 Gy), Dmax (46 vs 36 Gy), and V10-V30 (all p < 0.05). Baseline sexual function was 53 (±24) with 54% having severe ED with no difference between arms (p > 0.1). At 3 years average EPIC score was 39.7 (± 23) and 82% had severe ED with no differences between arms (p > 0.1). At enrollment 42% had EPIC > 60 with average summary of 77 (±8.3) which at 3 years was 53 (±24.8). In this sub-group at 3 years a higher EPIC was observed on the Spacer arm (57.7 (±24.1) vs. 44.6 (± 24.4)) which met the threshold for an MID without statistical significance (p = 0.07). Based on MID and twice that there was a trend favoring Spacer with 53% vs 75% for 11-point decline (p = 0.064) and 41% vs 60% for 22 point decline (p = 0.11). A small number of these men were potent at baseline and evaluable both at baseline and 3 years (n = 49). Of these 37.5% in the Control arm had erections sufficient for intercourse at 3 years as compared to 66.7% (p = 0.07) in the Spacer arm. Power analysis revealed 35% power to detect a change of 11 points between arms and 27% power to detect a difference of 22 points. Conclusions: The use of a hydrogel spacer decreased dose to the penile bulb with a suggestion of a clinically significant improvement in patient reported sexual function and potency. These did not achieve statistical significance potentially due to the high prevalence of ED at baseline and, therefore, the small evaluable sample size. Analysis of penile bulb dose and QOL is ongoing. Clinical trial information: NCT01538628.

Continued Benefit to Rectal Separation for Prostate Radiation Therapy: Final Results of a Phase III Trial

PURPOSE

SpaceOAR, a Food and Drug Administration-approved hydrogel intended to create a rectal-prostate space, was evaluated in a single-blind phase III trial of image guided intensity modulated radiation therapy. A total of 222 men were randomized 2:1 to the spacer or control group and received 79.2 Gy in 1.8-Gy fractions to the prostate with or without the seminal vesicles. The present study reports the final results with a median follow-up period of 3 years.

METHODS AND MATERIALS

Cumulative (Common Terminology Criteria for Adverse Events, version 4.0) toxicity was evaluated using the log-rank test. Quality of life (QOL) was examined using the Expanded Prostate Cancer Index Composite (EPIC), and the mean changes from baseline in the EPIC domains were tested using repeated measures models. The proportions of men with minimally important differences (MIDs) in each domain were tested using repeated measures logistic models with prespecified thresholds.

RESULTS

The 3-year incidence of grade ≥1 (9.2% vs 2.0%; P=.028) and grade ≥2 (5.7% vs 0%; P=.012) rectal toxicity favored the spacer arm. Grade ≥1 urinary incontinence was also lower in the spacer arm (15% vs 4%; P=.046), with no difference in grade ≥2 urinary toxicity (7% vs 7%; P=0.7). From 6 months onward, bowel QOL consistently favored the spacer group (P=.002), with the difference at 3 years (5.8 points; P<.05) meeting the threshold for a MID. The control group had a 3.9-point greater decline in urinary QOL compared with the spacer group at 3 years (P<.05), but the difference did not meet the MID threshold. At 3 years, more men in the control group than in the spacer group had experienced a MID decline in bowel QOL (41% vs 14%; P=.002) and urinary QOL (30% vs 17%; P=.04). Furthermore, the control group were also more likely to have experienced large declines (twice the MID) in bowel QOL (21% vs 5%; P=.02) and urinary QOL (23% vs 8%; P=.02).

CONCLUSIONS

The benefit of a hydrogel spacer in reducing the rectal dose, toxicity, and QOL declines after image guided intensity modulated radiation therapy for prostate cancer was maintained or increased with a longer follow-up period, providing stronger evidence for the benefit of hydrogel spacer use in prostate radiation therapy.

Phase II trial of concurrent sunitinib and image-guided radiotherapy for oligometastases

Background

Preclinical data suggest that sunitinib enhances the efficacy of radiotherapy. We tested the combination of sunitinib and hypofractionated image-guided radiotherapy (IGRT) in a cohort of patients with historically incurable distant metastases.

Methods

Twenty five patients with oligometastases, defined as 1–5 sites of active disease on whole body imaging, were enrolled in a phase II trial from 2/08 to 9/10. The most common tumor types treated were head and neck, liver, lung, kidney and prostate cancers. Patients were treated with the recommended phase II dose of 37.5 mg daily sunitinib (days 1–28) and IGRT 50 Gy (days 8–12 and 15–19). Maintenance sunitinib was used in 33% of patients. Median follow up was 17.5 months (range, 0.7 to 37.4 months).

Results

The 18-month local control, distant control, progression-free survival (PFS) and overall survival (OS) were 75%, 52%, 56% and 71%, respectively. At last follow-up, 11 (44%) patients were alive without evidence of disease, 7 (28%) were alive with distant metastases, 3 (12%) were dead from distant metastases, 3 (12%) were dead from comorbid illness, and 1 (4%) was dead from treatment-related toxicities. The incidence of acute grade ≥ 3 toxicities was 28%, most commonly myelosuppression, bleeding and abnormal liver function tests.

Conclusions

Concurrent sunitinib and IGRT achieves major clinical responses in a subset of patients with oligometastases.

Trial Registration

ClinicalTrials.gov NCT00463060

Prophylactic swallowing exercises in patients with head and neck cancer undergoing chemoradiation: a randomized trial

OBJECTIVE

To assess the efficacy of prophylactic swallowing exercises on swallowing function in patients undergoing chemoradiation therapy (CRT) for head and neck cancer.

DESIGN

Randomized controlled trial.

SETTING

Tertiary care, academic medical center.

PATIENTS

Twenty-six patients with head and neck cancer receiving CRT.

INTERVENTION

Patients performed 5 targeted swallowing exercises throughout their CRT and participated in weekly swallowing therapy sessions to promote adherence and accurate technique. Controls had no prophylactic exercises and were referred for swallowing treatment after completion of CRT if indicated.

MAIN OUTCOME MEASURES

Swallowing function was assessed with the Functional Oral Intake Scale (FOIS) and the Performance Status Scale for Head and Neck Cancer Patients (PSS-H&N) at baseline, immediately after CRT, and at 3, 6, 9, and 12 months after CRT.

RESULTS

There were no statistically significant differences in FOIS scores between intervention and control patients immediately after CRT (immediately after CRT: intervention group median score, 3 [range, 1-7], vs median control score, 4 [range, 1-6] (P = .88). However, intervention patients had significantly better scores at months 3 and 6 (median 3-month intervention score, 7 [range, 5-7], vs median control score, 5 [range, 3-7] [P = .03]; median 6-month intervention score, 7 [range, 6-7], vs median control score, 6 [range, 3-7] [P = .009]). There was no significant difference in scores at months 9 and 12 (P = .24 and P = .93, respectively). The same pattern between intervention and control patients was observed for scores on the PSS-H&N.

CONCLUSIONS

Patients who performed prophylactic swallowing exercises had improved swallowing function at 3 and 6 months after CRT but not immediately after CRT or at 9 and 12 months after CRT. The small sample size may have limited our ability to detect significant differences beyond 6 months of observation as well as additional significant differences in our study.

Prognostic significance of p16 in locoregionally advanced head and neck cancer treated with concurrent 5-fluorouracil, hydroxyurea, cetuximab and intensity-modulated radiation therapy

A phase II trial was conducted to evaluate the tolerability and efficacy of incorporating cetuximab and simultaneous integrated boost intensity-modulated radiation therapy (SIB-IMRT) into a well-described 5-fluorouracil (5-FU) and hydroxyurea (HU)-based chemoradiation regimen. Patients with stage IVa-IVb or high-risk stage III squamous cell carcinomas were enrolled. Prior organ-conserving surgery or induction chemotherapy was allowed. IMRT was administered in 1.5 Gy fractions twice daily on days 1-5 of weeks 1, 3, 5, 7±9 for a total dose of 60-73.5 Gy. Concurrent systemic therapy consisted of 5-FU (600 mg/m2), HU (500 mg BID) and cetuximab (250 mg/m2). p16INK4A expression was assessed by immunohistochemistry. From January 2007 to January 2010, 65 patients (61 with stage IV disease; 31 with oropharyngeal primaries) were enrolled. At a median follow-up of 28 months, 2-year locoregional control, distant control, progression-free survival, event-free survival and overall survival were 79, 83, 72, 63 and 80%, respectively. In 48 patients with available pre-treatment tissue, p16 overexpression was associated with significantly increased distant control (p=0.03), progression-free survival (p=0.02), event-free survival (p=0.007) and overall survival (p=0.03). The most common grade 3-4 toxicities were mucositis (46%), leukopenia (18%), anemia (18%) and dermatitis (17%). Concurrent 5-FU, HU, cetuximab and SIB-IMRT is a highly active regimen, particularly in patients with p16-positive disease.

Comparison of a novel FiberWire-button construct versus metallic screw fixation in a syndesmotic injury model

BACKGROUND

There is minimal experience with less rigid syndesmotic fixation devices which may approximate the normal distal tibio-fibular mechanics during healing. This study evaluates the ability of a FiberWire-button implant (Arthrex, Naples, FL) to maintain syndesmotic reduction as compared with a metallic screw.

METHODS

Ten matched fresh-frozen cadaveric ankle pairs with intact ligaments were tested (12.5 Nm external rotation force) to establish physiologic syndesmotic diastasis. The same force was applied to the ankles after sectioning of the syndesmotic and deltoid ligaments. Within the pairs, each limb was randomized to receive a FiberWire-button implant or a metallic screw (Synthes, Paoli, PA); the ankles were tested for syndesmotic diastasis with progressive external rotation force, from 2.5 Nm to 25 Nm (or failure).

RESULTS

There was no significant difference in diastasis amongst pairs with intact or sectioned syndesmosis (p=0.64 and p=0.80, respectively). There was a significantly greater diastasis in the FiberWire-button group at all external rotation loads (p<0.0001). Nine of the ten pairs failed (all through fracture of the distal fibula). There were no hardware failures. The metallic screw group failed at a lower load (mean 15 Nm) compared to the FiberWire-button group (mean 18 Nm, p=0.0004). The metallic screw group maintained syndesmotic reduction up to 5 Nm of force.

CONCLUSIONS

The FiberWire-button was unable to maintain syndesmotic reduction of the ankles at any of the forces applied. The ankles fixed with the FiberWire-button demonstrated significantly greater widening of the syndesmosis compared to the screw, at all loads.

CLINICAL RELEVANCE

The FiberWire-button implant may not maintain adequate ankle syndesmotic reduction in the immediate post-operative period relative to a metallic screw.

Expression and function of erythropoietin receptors in tumors

Safety concerns surrounding the use of recombinant human erythropoietin (Epo) to treat anemia in cancer patients were raised after 2 recent clinical studies reported a worse survival outcome in patients who received epoetin alpha or epoetin beta compared with patients who received placebo. Although those findings contrasted with previous clinical studies, which demonstrated no difference in survival for cancer patients who received erythropoiesis-stimulating agents (ESAs), some investigators have suggested a potential role for ESAs in promoting tumor growth through 1) stimulation of Epo receptors (EpoR) expressed in tumors, 2) stimulation and formation of tumor vessels, and/or 3) enhanced tumor oxygenation. The first and second hypotheses appeared to be supported by some EpoR expression and ESA in vitro studies. However, these conclusions have been challenged because of poor specificity of EpoR-detection methodologies, conflicting data from different groups, and the lack of correlation between in vitro data and in vivo findings in animal tumor models. For this report, the authors reviewed the biology of EpoR in erythropoiesis and compared and contrasted the reported findings on the role of ESAs and EpoR in tumors.

BCR-ABL-induced adhesion defects are tyrosine kinase-independent

The t(9;22) chromosomal translocation results in expression of P210(BCR-ABL), a fusion protein necessary for the development of chronic myelogenous leukemia (CML). The constitutive activation of the P210(BCR-ABL) tyrosine kinase results in phosphorylation of multiple signaling pathways leading to the transformed phenotype. Additionally, extracellular interactions between P210(BCR-ABL)-expressing progenitor cells and bone marrow stroma may provide external signals that facilitate CML development. In contrast to the intracellular signaling pathways involved in CML, little is known about how P210(BCR-ABL) expression modifies cell-cell and cell-substratum interactions. To investigate the role of P210(BCR-ABL) in modulating cellular adhesion, we used a highly sensitive and quantitative cell detachment apparatus that measures the strength of association between a population of cells and an adhesive matrix. Our findings show that P210(BCR-ABL) expression increased adhesion nearly 2-fold between the myeloblastic cell line, 32D, and fibronectin compared to a control vector. We then investigated whether abnormal adhesion due to P210(BCR-ABL) expression was caused by its tyrosine kinase activity. A quantitative analysis of cell-fibronectin adhesion found that neither expression of a kinase-inactive P210(BCR-ABL) mutant in 32D cells or attenuation of kinase activity by STI571 (imatinib mesylate) in 32D cells transduced with wild-type P210(BCR-ABL) could correct the nearly 2-fold increase in cell-fibronectin adhesion. Similarly, STI571 treatment of Meg-01 cells, a P210(BCR-ABL)-expressing cell line derived from a patient in blast crisis, failed to inhibit adhesion to fibronectin. Together, our results indicate that changes in adhesion induced by P210(BCR-ABL) are independent of its tyrosine kinase activity.