A real-life experience using panitumumab in chemo-refractory metastatic colorectal cancer patients: a retrospective analysis at the Jewish General Hospital, 2009-2012

BACKGROUND

Panitumumab is a fully human monoclonal antibody, directed against the epidermal growth factor receptor, that was shown to be effective in third-line metastatic colorectal cancer. We performed a retrospective analysis of patients with chemo-refractory non-KRAS-mutated metastatic colorectal cancer, who received panitumumab at the Jewish General Hospital in Montreal, Canada, between 2009 and 2012.

METHODS

This chart review included 44 patients (median age: 60 years; performance status: 0-3), of whom 50% had already received three lines of treatment. The primary endpoint was progression-free survival (pfs). Secondary endpoints were overall survival and safety. Tumour progression was determined by radiologic assessments performed once every 3 months per clinical guidelines or by clinical deterioration as determined by the clinician-investigator.

RESULTS

In our sample, median pfs was 21.86 ± 5.23 weeks (95% confidence interval: 12.9 to 36.9 weeks) and overall survival was 35.14 ± 7.75 weeks (95% confidence interval: 25.6 to 73.4 weeks) with a median of 5 cycles of panitumumab treatment. The most frequently reported toxicities with panitumumab were skin toxicity (16.2% grade 3) and hypomagnesemia (10.8% grade 3). No infusion reactions were reported.

CONCLUSIONS

Despite a small sample size from a single institution, our survival and efficacy data are encouraging and comparable to results obtained from the registration panitumumab trial. Our findings suggest that panitumumab can be effective and tolerable in a real-world setting.

Anti-tumor necrosis factor-a for the treatment of steroid-refractory acute graft-versus-host disease

Allogeneic stem cell transplantation has been increasingly performed for a variety of hematologic diseases. Clinically significant acute graft-versus-host disease (GVHD) occurs in 9 to 50% of patients who receive allogeneic grafts, resulting in high morbidity and mortality. There is no standard therapy for patients with acute GVHD who do not respond to steroids. Studies have shown a possible benefit of anti-TNF-a (infliximab)for the treatment of acute GVHD. We report here on the outcomes of 10 recipients of related or unrelated stem cell transplants who received 10 mg/kg infliximab, iv, once weekly for a median of 3.5 doses (range: 1-6) for the treatment of severe acute GVHD and who were not responsive to standard therapy. All patients had acute GVHD grades II to IV (II = 2, III = 3, IV = 5). Overall, 9 patients responded and 1 patient had progressive disease. Among the responders, 3 had complete responses and 6 partial responses. All patients with cutaneous or gastrointestinal involvement responded, while only 2 of 6 patients with liver disease showed any response. None of the 10 patients had any kind of immediate toxicity. Four patients died, all of them with sepsis. Six patients are still alive after a median follow-up time of 544 days (92-600) after transplantation. Considering the severity of the cases and the bad prognosis associated with advanced acute GVHD, we find our results encouraging. Anti-TNF-a seems to be a useful agent for the treatment of acute GVHD.

Radical vaginal trachelectomy (Dargent's operation): A critical review of the literature

AIMS

To present a review of the most recent articles about radical vaginal trachelectomy (RVT).

METHODS

Recent literature has been reviewed, concentrating on surgical, oncological and obstetrical outcome of RVT. Data for this review were identified by searches of PubMed, and references from relevant articles using the search terms "trachelectomy" and "radical vaginal trachelectomy", "cervical carcinoma", and "fertility saving".

FINDINGS

Although a considerable number of women in their reproductive years have been diagnosed with cervical carcinoma, conservative management of early-stage cervical carcinoma did not come into practice until the beginning of the new millennium. To date, 7 gynecologic oncologic centers worldwide have reported oncological and pregnancy outcomes since Dargent made his first announcement of radical vaginal trachelectomy (RVT) in 1994. Recurrence and death rates (4.2% and 2.8%, respectively) of RVT seem to be comparable to classical radical abdominal hysterectomy. It appears that RVT's overall recurrence and death rates were similar to early-stage cervical cancer treated by radical hysterectomy (RH) or radiotherapy. Furthermore fertility results of RVT seem to be promising. A 70% pregnancy rate was reported in the women who wanted to conceive following RVT, though such patients should be informed about the risk of second trimester loss and preterm delivery. On the other hand, there is a lack of satisfactory information about the follow-up of post-RVT patients, both after the operation and during subsequent pregnancy.

CONCLUSION

RVT looks as if it is a valid uterus-conserving surgery for women of reproductive age who have early-stage cervical carcinoma. However, in order to reach a final conclusion about the oncological and obstetrical results, further studies are needed with larger sample sizes and longer follow-up periods.

Sensory conduction velocity of dorsal nerve of the penis during pharmacoerection: a more physiological technique?

OBJECTIVE

Sensory conduction velocity (SCV) of the dorsal nerve of the penis is technically difficult to perform at rest and very slow SCV has been observed in the literature. This study evaluates the effect of pharmacoerection on the SCV measurement.

METHODS

Twenty-four men, 16 with a normal neurologic examination, 8 with a diabetic neuropathy, were studied at rest and after a 20-micrograms injection of prostaglandin E1.

RESULTS

Only 5 subjects had a recordable potential at rest. The mean SCV increased from 32.3 +/- 6.7 to 47.4 +/- 8.2 m/s after injection. Nine had only a recordable potential after injection. Ten had no potential at all, but 6 of them had a diabetic neuropathy.

CONCLUSION

Pharmacoerection was helpful in 37.5% of the subjects to obtain a sensory potential. Moreover, pharmacoerection may be the best way of calculating dorsal nerve SCV, as 47.4 m/s is what should be expected for a large myelinated nerve. This may be due to a correct interelectrode distance measurement as full tumescence may straighten the nerve at an individual and physiological length.

Synaptic effects of halogenated anesthetics on short-latency SEP

We evaluated the effects of different stable end-tidal concentrations of isoflurane, enflurane, or halothane on short-latency somatosensory evoked potentials recorded during general anesthesia. Isoflurane and enflurane significantly enhanced the P22 over the pre-central scalp, whereas the parietal N20 amplitude did not increase. The P22 increase did not occur with halothane, which indicates that the P22 changes are a specific effect of certain anesthetics, probably related to their influence on synaptic events. At the subcortical level, isoflurane and enflurane increased significantly the N13 peak latency and decreased the interval between the N13 peak and P14 peak, which implicates interference with synaptic transmission at the spinal level. Halothane had no effect at the spinal level. All three anesthetics significantly increased the central conduction time.

Acute effects of diphenylhydantoin on peripheral and central somatosensory conduction

We studied the acute effects of an intravenous loading dose of DPH (16 mg/kg body weight) on peripheral and central somatosensory conduction in 10 normal volunteers. Somatosensory evoked potentials were recorded before and at regular intervals after DPH infusion. There was no effect on peripheral conduction. DPH significantly delayed N13 peak latency without changing conduction in the posterior spinal columns. Although the N13-N20 interpeak interval remained stable because of the parallel shift of the 2 peaks, the central conduction time measured from onset latencies of N11 and N20 significantly increased. We conclude that acute administration of DPH at serum levels below 30 micrograms/ml induces a reversible delay of synaptic transmission in spinal and central somatosensory structures.

Urinary retention due to sacral myeloradiculitis: a clinical and neurophysiological study

We report 5 cases of sacral myeloradiculitis presenting with transient urinary retention. Neurophysiological testing, including bulbocavernosus reflex, pudendal evoked response and external anal sphincter electromyography, was performed. Parasympathetic pelvic nerves, pudendal nerves as well as the spinal cord seem to be involved to various degrees in this infrequent disorder.

Neurophysiological investigations of two hundred men with erectile dysfunction. Interest of bulbocavernosus reflex and pudendal evoked responses

Two-Hundred consecutive patients complaining of impotence have had complete urological and neurophysiological investigations to determine a possible organic cause of their sexual dysfunction. All patients had urological and neurological history and examination: nocturnal penile plethysmography, papaverine intracavernosus injection, penile arterial doppler and/or arteriography, cavernography-cavernometry, serum hormonal levels, and bulbocavernosus reflex (BCR). Peripheral conduction velocities and pudendal-evoked responses (PER) were also performed if neurological history or examination and/or BCR were abnormal. Only 30 patients (15%) had an abnormal BCR. In 17 patients, a neurological associated disorder was found. Four patients had normal erections during plethysmography, despite their complaints. Nine patients with an isolated prolonged BCR also presented a vascular abnormality that could explain impotence. Abnormal PER was observed only in 6 patients, 4 of them with a prolonged BCR as well. These results suggest that PER is not an interesting neurophysiological routine test for the diagnosis of neurogenic impotence and that the relationship between an abnormal BCR and neurogenic impotence is doubtful.

Role of the bulbocavernosus muscles on the mechanism of human erection

The role of the human bulbocavernosus muscles on the intracavernous pressure and on the venous return were investigated during artificial erection. Contractions of these muscles were voluntary or produced by dorsal nerve stimulation. During such contractions, elevations in intracavernous pressure and a decrease in the erectile flow rates to produce and to maintain the erection were observed. These results demonstrate involvement of the bulbocavernosus muscles in the process of penile rigidity and suggest that they could participate in the mechanism of rigidity during intercourse.

Differential effects of isoflurane on SEP recorded over parietal and frontal scalp

We evaluated the effects of different concentrations of isoflurane on short-latency somatosensory evoked potentials recorded over the parietal and frontal scalp in 14 patients during general anesthesia at stable end-tidal concentrations between 0% and 2.5%. At concentrations between 0% and 1%, there was a marked discrepancy between the amplitude of the parietal N20, which remained stable, and the striking increase of the frontal P22. At concentrations above 1.5%, the parietal N20 disappeared in 6 patients whereas the P22 was clearly identified in 12. The central conduction time increased significantly whereas the spinal conduction was not delayed by increasing levels of isoflurane. These results show that isoflurane anesthesia is a useful pharmacologic model to demonstrate the independence of the N20 recorded over the parietal scalp and the P22 recorded over the frontal scalp.