Collagen XXIII expression is associated with prostate cancer recurrence and distant metastases

PURPOSE

We had previously identified a new transmembrane collagen, type XXIII, in metastatic rat prostate carcinoma cells. The purpose of this study was to determine the expression of collagen XXIII in human prostate cancer and investigate its relationship with disease progression.

EXPERIMENTAL DESIGN

We investigated collagen XXIII expression in prostate cancer tissue and did a retrospective analysis of association with prostate-specific antigen (PSA)-defined disease recurrence. The presence of collagen XXIII in prostate cancer patient urine was also assessed before and after prostatectomy.

RESULTS

Collagen XXIII protein was detected at very low levels in benign prostate tissue and was significantly increased in prostate cancer. Distant metastases exhibited significantly higher collagen XXIII levels compared with either localized prostate cancer or regional (lymph node) metastases. Patients with high collagen XXIII levels had a 2.8-fold higher risk of PSA failure with median time to failure of 8.1 months, compared with low collagen XXIII patients with a median time to failure of 5 years. Multivariate Cox regression showed that the presence of collagen XXIII was significantly associated with time to PSA recurrence, independent of other clinical variables. Collagen XXIII was also detected in prostate cancer patient urine, with reduced levels after prostatectomy, indicating potential as a noninvasive fluid biomarker.

CONCLUSIONS

We present the first report demonstrating increased collagen XXIII expression in prostate cancer tissue. We show that collagen XXIII level is a significant independent predictor of PSA-defined disease recurrence, suggesting a potential role as a molecular biomarker of prostate cancer progression and metastasis.

“Blind Coning”—Using the Stone Cone for Removal of Intramural Ureteral Calculi

INTRODUCTION

To describe the otherwise heretical technique of "blind" nonureteroscopic extraction of calculi from the intramural ureter using a 7-mm-diameter tapered coil called the "Stone Cone."

TECHNICAL CONSIDERATIONS

After bypassing the stone and deploying the Stone Cone, slow traction was exerted. The Stone Cone's 5, 6, and 7-mm diameter coils and unique rotary action dilated the tunnel distal to the calculus and the 2, 3, and 4-mm stiffer coils caught the calculus and propelled it out of the transiently dilated intramural ureter. A safety feature is that the coils of the Stone Cone will unwind at greater than 0.2-lb tension. Unlike the baskets, if a pressure greater than this is encountered, the Stone Cone will release the stone, preventing entrapment.

CONCLUSIONS

In selected cases, use of the Blind-Cone to remove an intramural calculus can be a rapid, effective, and safe alternative to ureteroscopic management.

Diagnosis and management of dysfunctional voiding

PURPOSE OF REVIEW

This review will focus on the diagnosis and management of voiding dysfunction in neurologically and anatomically normal children. The discussion will highlight recent developments and research in the clinical approach as well as the etiology and classification of these disorders.

RECENT FINDINGS

Voiding dysfunction in children encompasses a wide spectrum of clinical entities, recently classified collectively as dysfunctional elimination syndromes. Voiding dysfunction typically presents after toilet training and may originate from behavioral issues that arise around this time in childhood development. The spectrum of disorders includes urge syndrome, dysfunctional voiding with an uncoordination between the detrusor and urinary sphincter, and enuresis. Clinical symptoms may vary from mild incontinence to severe disorders with endpoints of irreversible bladder dysfunction with vesicoureteral reflux, urinary tract infection and resulting nephropathy. Diagnosis relies heavily on a good history and physical examination, but also includes radiologic and urodynamic evaluation. Treatment generally consists of medical therapy, primarily with anticholinergics as well as behavioral therapy to modify learned voiding patterns that contribute to the voiding dysfunction.

SUMMARY

This overview of voiding dysfunction in children outlines the established approaches to its diagnosis and treatment and highlights the most recent developments in the field.

Effects of stimulus duration and stimulus off time on the auditory and acoustic reflex thresholds

The effects of stimulus duration and stimulus off time on the thresholds of hearing and the acoustic reflex were investigated in 10 normal-hearing subjects and 10 subjects with sensorineural hearing loss. A 1000-Hz stimulus with on-off times of 500-500 msec and 30-30 msec was used to obtain hearing sensitivity and acoustic reflex thresholds via a tracking method. Auditory threshold was poorer for the 30-30 msec tone than the 500-500 msec stimulus in both groups. Using the different stimuli, no significant difference in acoustic reflex threshold was observed in either group. These results suggest that the addition of a short off time modifies the previously observed effects of both duration and off time on the acoustic reflex and auditory threshold.

Diagnostic application and interpretation of tympanometry and the acoustic reflex

Tympanometry and the acoustic reflex constitute a powerful middle ear measurement battery. Together, these measurements provide us with direct objective information about the integrity and mobility of the middle ear system and the status of the sensorineural auditory function. A descriptive analysis of tympanograms involves a consideration of the amplitude and shape of the tympanogram as well as the location of the peak along the air pressure axis. The differential effect of pathology on tympanogram pressure peak location, amplitude and shape as well as on the acoustic reflex provides the capability for the application of this battery in the differential diagnosis of auditory disorders.

Tympanometry: application and interpretation

The poor relationship between hearing loss and ear disease minimizes the effectiveness of audiometry as a technique for the identification of middle ear disorders. Tympanometry has been shown to be a highly sensitive technique for the identification of and differentiation between middle ear disorders. It is particularly useful in a pediatric population where ear disease is so frequently encountered. The interpretation of tympanometry on the basis of a descriptive analysis of tympanograms is proposed as opposed to a coded typing system. Descriptive analysis views the pathological effects of middle ear diseases on pressure peaks, amplitude and shape of tympanograms.

A report of further impedance studies of the acoustic reflex

The result of acoustic stimulation of the middle ear muscles was studied using subjects in whom one or the other muscle contraction was known to be ineffective. Otosclerosis presented a condition of an intact pair of muscles but a stapes unresponsive to the contraction of the stapedius muscle. Bell’s Palsy represented a condition of a paralyzed stapedius muscle but an otherwise normal middle ear system. Through surgical intervention the ears of otosclerotic patients were altered by sectioning of the stapedius muscle and insertion of a prosthesis, while in other patients an exploratory tympanotomy verified that the middle ear was without pathology and then one or the other of the middle ear muscles was sectioned. All except one of these instances would eliminate the response of the stapedius muscle only, while the other would only eliminate the tensor tympani response. In each instance of restriction of response of the stapedius muscle the acoustic reflex could not be elicited. On the other hand, when the remainder of the system was intact and only the tensor tympani sectioned, the acoustic reflex appeared normal. These observations would strongly support the contention that the tensor tympani is not responsive to acoustic stimulation.