Complications following surgery with or without radiotherapy or radiotherapy alone for prostate cancer.

BACKGROUND: Men undergoing treatment of clinically localised prostate cancer may experience a number of treatment-related complications, which affect their quality of life. METHODS: On the basis of population-based retrospective cohort of men undergoing surgery, with or without subsequent radiotherapy, or radiotherapy alone for prostate cancer in Ontario, Canada, we measured the incidence of treatment-related complications using administrative and billing data. RESULTS: Of 36 984 patients, 15 870 (42.9%) underwent surgery alone, 4519 (12.2%) underwent surgery followed by radiotherapy, and 16 595 (44.9%) underwent radiotherapy alone. For all end points except urologic procedures, the 5-year cumulative incidence rates were lowest in the surgery only group and highest in the radiotherapy only group. Intermediary rates were seen in the surgery followed by radiotherapy group, except for urologic procedures where rates were the highest in this group. Although age and comorbidity were important predictors, radiotherapy as the primary treatment modality was associated with higher rates for all complications (adjusted hazard ratios 1.6-4.7, P=0.002 to <0.0001). CONCLUSIONS: In patients treated for prostate cancer, radiation after surgery increases the rate of complications compared with surgery alone, though these rates remain lower than patients treated with radiation alone. This information may inform patient and physician decision making in the treatment of prostate cancer.

Traumatic intimal tear of the renal artery treated by insertion of a Palmaz stent.

A renal artery intimal injury induced by blunt trauma in a 23-year-old man was treated by percutaneous placement of a Palmaz endovascular stent. The patient was placed on anticoagulation for 2 months following stent insertion. Nuclide renal scans demonstrated recovery of normal renal function on the affected side at 9 months postprocedure.

Is CNS trauma a prerequisite for the elongation of CNS axons into denervated peripheral nerve?

The demonstration that some central nervous system (CNS) axons can regenerate when provided with a suitable environment raises the possibility of new treatments for CNS injury. However, at present the conditions for optimal regeneration are not well understood. For example, the methods used in previous studies have entailed CNS trauma as part of the research protocol (e.g. that resulting from the implantation of peripheral nerve grafts), and so the role of neuronal or axonal injury in the regrowth observed has been difficult to establish. To determine whether such injury is necessary for the central reinnervation of denervated peripheral nerve, the L5 dorsal root has been chronically denervated in rats by freeze-thawing its dorsal root ganglion (DRG), and the root has been left attached to either traumatized or non-traumatized spinal cord. The trauma induced was quite mild, and resulted from several vertical insertions of a fine needle. Two to 4 months later, retrogradely transported horseradish peroxidase (HRP) was used to label spinal neurons which sent axons into the denervated roots. HRP-labelled neurons were found in each of the spinal cords subjected to trauma, but no labelled neurons were observed in any of the non-traumatized cords. The number of HRP-labelled neurons in individual spinal cords was positively correlated with the degree of spinal cord trauma. We conclude first that the chronic and intimate presence of a denervated PNS tissue in continuity with the spinal cord is not, in itself, a sufficient stimulus to induce its reinnervation by CNS axons. Second, we conclude that under the conditions of this experiment CNS trauma is a prerequisite for the reinnervation of denervated peripheral nervous tissue by CNS axons.

Reinnervation of denervated skeletal muscle by central neurons regenerating via ventral roots implanted into the spinal cord.

The reinnervation of denervated skeletal muscle by central axons regenerating via a ventral root implanted into the spinal cord was examined in rats. The 8th thoracic ventral root was severed and its distal end implanted into the ventro-lateral column of the spinal cord via a stab incision. In control animals the root was severed, but was not implanted into the stab incision. After 12-14 months the animals were examined electrophysiologically to determine the presence or absence of motor units in the 8th intercostal muscle which were reinnervated by centrally derived axons regenerating via the implant. Such units were found in implanted animals, but in none of the controls. Evidence that the motor units were reinnervated by central axons included the facts that the units could be activated either, (1) reflexly (i.e. trans-synaptically) by electrical stimulation of the dorsal roots or spinal cord, or (2) pharmacologically by either the intraspinal injection of glutamate or acetycholine, or by the systemic administration of strychnine. Great care was taken to ensure that the only feasible connection between the spinal cord and the 8th intercostal muscle was via the site of implantation. The EMG signals from the motor units were of large amplitude, typical of reinnervated muscle, and their individual activation resulted in discernible contractions of regions of the T8 intercostal muscle. We conclude that regenerating CNS neurons can be guided to innervate denervated skeletal muscle by the implantation of severed ventral roots into the spinal cord. The neuromuscular synapses formed are functional and persistent. The findings may be relevant to the restoration of function after nervous injuries, such as the avulsion of ventral roots.