Phase-1 study of isophosphoramide mustard (IPM)-lysine in advanced cancers

9524

Background: IPM is a bi-functional alkylator which cross-links DNA through G:C base-pairs resulting in irreparable 7-atom inter-strand cross-links. IPM is the active moiety of ifosfamide (IFOS), a pro-drug of IPM. IPM is active in diverse cancer models but is unstable. We stabilized IPM with lysine (IPM-lysine; ZIO-201). ZIO-201 was active in pre-clinical models including human cancer cell lines, human-mouse xenografts and cancers resistant to cyclophosphamide (CPA) and IFOS. Because ZIO-201 is not metabolized to acrolein or chloroacetaldehyde, bladder and CNS toxicities are unlikely. Methods: Phase-1 trial in subjects with advanced cancers. ZIO-201 was given daily for 3 consecutive d at a starting dose of 30 mg/me2/d every 3 w. Neither mesna nor IV hydration were given. 11 dose levels were studied in 18 subjects up to 795 mg/me2/d; dose-escalation continues. Data on the 1st 15 subjects are available for analysis. Results: Median age was 59 y (range, 18–70 y); 10 subjects were male. Diagnoses included colorectal cancer (N=5), sarcoma (N=3) and 1 subject each with gastric, lung, bladder, prostate, ovary and thyroid cancers and mesothelioma. 7 had extensive and 8, limited disease. All subjects received extensive prior therapy. Median N cycles was 2 (range, 1–13). Toxicities ≥ grade-2 occurring in > 20% of subjects included anemia (N subjects=4) and diverse GI complaints (N=4). 4 of 8 subjects receiving doses > 445 mg/me2/d had transient proximal renal tubular acidosis. There was no hemorrhagic cystitis or CNS toxicity. 1 subject with mesothelioma had stable disease > 13 mo. Pharmacokinetic studies at 595 mg/me2/d showed a tmax = 13 min (SD ± 9 min), Cmax = 44.7 μg/mL (SD ± 34.1 μg/mL), t1/2 = 35 min (SD ± 7 min) and AUC0-∞ = 1.68 mg·min/ml (SD ± 1.26 mg·min/ml). Conclusions: These data suggest a possible role for ZIO-201 in IFOS-sensitive cancers (especially sarcoma and lymphoma). ZIO-201 may also be active in CPA and IFOS-resistant cancers. Comparable or greater efficacy with less toxicity is expected.

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Safety and antitumor activity of AMG 706 in patients (pts) with thyroid cancer (TC): A subset analysis from a phase 1 dose-finding study

3030

Background: AMG 706 is an investigational, oral, small molecule multi-kinase inhibitor with both antiangiogenic and direct antitumor activity that selectively targets VEGF, PDGF, and Kit receptors. From a phase 1 study (Rosen ASCO 2005; Herbst EORTC 2005), encouraging antitumor activity was seen in pts with TC. In this analysis, we report on the TC subset from the study. Methods: Pts with refractory solid tumors received oral AMG 706 QD (50, 100, 125, 175 mg) or BID (25 mg) intermittently or continuously for 28-day cycles. Study objectives were to assess safety, establish the maximum tolerated dose (MTD), and generate pharmacokinetic profiles of AMG 706 in these pts. Tumor response (modified RECIST) was evaluated at wk 8 and Q12W thereafter. Data from Oct 2005 were analyzed. Results: In this study, 7 of 71 pts enrolled had TC. Baseline demographics for this subset were 4 W/3 M, median (range) age of 58 (41, 78) yrs, ECOG 1 (71%), and all had stage IV disease. Histologies were papillary (3: PTC), follicular (1; FTC), Hürthle cell (1), anaplastic (1), and medullary TC (1; MTC). All pts received prior external radiotherapy, radioiodine, chemotherapy, and/or surgery. Initial doses of AMG 706 were 125 mg and 175 QD and 25 mg BID. The MTD for the study was 125 mg QD. Median (range) time on treatment for the TC pts was 141 (14, 564) days. Treatment-related adverse events are summarized ( table ). Best objective responses were 3 pts with partial response (PR), 3 with stable disease (SD), and 1 with progressive disease. PR was seen in pts with MTC, PTC and FTC. Two pts with PR did not have confirmation of response (1 had a PR during the last assessment). The 3 pts with PR received AMG 706 for 338, 366, and 564 days; 2 pts are still receiving AMG 706. Time to response for these 3 pts were 210, 217, and 304 days. Conclusion: In patients with TC, AMG 706 appears to be relatively well tolerated and displays promising antitumor activity for some pts. Based on these favorable findings, a phase 2 study of AMG 706 for the treatment of advanced TC is ongoing.

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Actual colonoscopy: what are the risks of perforation?

Recent studies have suggested that virtual colonoscopy (VC) and actual colonoscopy (AC) have similar efficacy for detection of polyps >6 mm. However, procedural risks with emerging technology such as VC need to be assessed before widespread implementation. We propose to demonstrate complication rates after AC that can be used for a comparative benchmark in VC. From 1994 to 1999 all patients undergoing AC who sustained perforation that required operation were analyzed for the mortality and complications. There were 26,162 consecutive colonoscopies that required 21 operations for perforation. Of these 16,948 (65%) colonoscopies were diagnostic and 9,214 (35%) were therapeutic with 11 (0.06%) and 10 (0.11%) operations respectively. Overall risk for colonoscopic perforation that requires operation was one in 1,246 (one in 1,541 for diagnostic and one in 921 for therapeutic). Five perforations were oversewn, 15 were resected (five with stoma), and one was drained. One patient died. There were two reoperations. Mortality was 0.006 per cent (one in 16,948) for diagnostic and zero for therapeutic colonoscopy. Overall risk for perforation that requires operation or mortality after AC is low. Virtual colonoscopists who propose screening and subsequent therapeutic interventions need to report high volume without complications as the perforation rate requiring operation was one in 1,246.

Rectal prolapse: a search for the "best" operation

There is a lack of consensus regarding the optimal operative treatment for full-thickness rectal prolapse. We describe our experience in the management of procidentia and evaluate our current practice for improvement of results. The medical records of patients undergoing surgery for rectal prolapse between 1989 to 1999 were retrospectively reviewed. A total of 36 perineal proctosigmoidectomies (PPSs) and 29 abdominal procedures [17 anterior resections (ARs) and 12 Ripstein procedures (RPs)] were performed during the 10-year period. Patients undergoing PPS were significantly older and had more comorbidities. Mean operating time and length of hospital stay were shorter for the PPS group. Early and late postoperative complication rates were also significantly lower in the PPS group. Six patients (16%) in the PPS group developed recurrence at a mean follow-up of 50 months. Operation under general anesthesia or removal of a longer segment of prolapsed bowel did not reduce recurrence after PPS. No full-thickness recurrence was noted after AR or RP. We conclude that abdominal procedures (AR and RP) have the lowest recurrence but at a significantly higher cost in terms of complications. PPS is a valuable option in selected patients and can be performed with minimal morbidity and a relatively low recurrence rate.

Readmissions after colorectal surgery cannot be predicted

INTRODUCTION

Readmission after discharge from the hospital is an undesirable outcome. In an attempt to prevent unplanned readmissions after abdominal or perineal colon resection, we proposed to identify risk factors associated with return to the hospital.

METHODS

Study participants consisted of 249 patients who were operated on from July 1, 1996, to March 30, 1998. All patients who were readmitted within 90 days of discharge from the hospital after surgery were evaluated for the study. A retrospective review of charts was performed to assess whether readmission within 90 days was a direct consequence of the recent operation (unplanned related readmission). These patients were compared with a control group consisting of patients who were never readmitted or who were readmitted with an unrelated problem.

RESULTS

Of the 249 patients, 59 (24 percent) were readmitted within 90 days of discharge from the hospital. Twenty-two (9 percent) were unplanned related readmissions. Ten patients were readmitted with unrelated emergencies, and 27 patients were readmitted electively. In the unplanned related group, there was no correlation between age, gender, admission diagnosis, activity status, or postoperative length of stay and the likelihood of readmission. Patients with multiple chronic medical problems or those who developed postoperative complications did not have a higher readmission rate. Patients with ulcerative colitis or those who underwent abdominoperineal resection or total/subtotal colectomy had a higher incidence of readmissions, although the difference was not significant. The mean interval between discharge from the hospital and readmission with a related complication was 19 days. Small-bowel obstruction was the most common reason for readmission, and all cases resolved with conservative management. Mean length of stay during all readmissions was 8 days.

CONCLUSION

The incidence of unplanned related readmissions 90 days after abdominal or perineal colon resection is 9 percent, and these readmissions could not be predicted from the postoperative course. Because 82 percent of unplanned readmissions occurred within 30 days, this time frame is suitable for computerized comparative analysis.

Effect of sand fly saliva on Leishmania uptake by murine macrophages

Leishmania promastigotes are introduced into the skin by blood-sucking phlebotomine sand flies. In the vertebrate host, promastigotes invade macrophages, transform into amastigotes and multiply intracellularly. Sand fly saliva was shown to enhance the development of cutaneous leishmaniasis lesions by inhibiting some immune functions of the host macrophages. This study demonstrates that sand fly saliva promotes parasite survival and proliferation. First, macrophages gravitated towards increasing concentrations of sand fly saliva in vitro. Secondly, saliva increased the percentage of macrophages that became infected with Leishmania promastigotes and exacerbated the parasite load in these cells. Thus, during natural transmission, saliva probably reduces the exposure of promastigotes to the immune system by attracting macrophages to the parasite inoculation site and by accelerating the entry of promastigotes into macrophages. Saliva may also enhance lesion development by shortening the generation time of dividing intracellular amastigotes.

Computerized assessment of complications after colorectal surgery: is it valid?

PURPOSE

Historically, complication rates after colorectal surgery have been stratified by disease process, type of operation, or anesthesia risk derived after an intensive review of the medical record. Newer computer applications purport to shorten this process and predict the probability of postoperative complications by distinguishing them from comorbidities that are commingled on uniform discharge codes. We analyzed CaduCIS software, which uses discharge codes, to determine whether its predictions of comorbidity and complications were comparable to what was interpreted on the medical record.

METHODS

Two-hundred seventy patients were analyzed according to the principal and secondary diagnoses coded on discharge. Coding inaccuracies of clinical occurrences were identified by physician review of each medical record. The actual incidences of 17 common preoperative comorbidities and 11 postoperative complications were compared with those predicted by CaduCIS.

RESULTS

The CaduCIS-predicted distribution of comorbidities was similar to the actual occurrences in 15 of 17 categories. The overall incidence of complications obtained by physician (actual) review was 47 percent, compared with 46 percent predicted by CaduCIS. However, there was a statistical difference between the CaduCIS-predicted and the actual complication rates in 5 of the 11 categories. The most common preoperative comorbidity and complication was cardiopulmonary (47 percent and 28 percent, respectively).

CONCLUSION

The overall complication rate interpreted from the medical record (47 percent) was accurately predicted by CaduCIS (46 percent). Predictions of 5 of 11 individual complications were underestimated because of charting and coding inaccuracies, not because of computerized errors. Because uniform discharge coding of commingled comorbidity and complications is increasingly used to rapidly compute surgical outcomes, colon and rectal surgeons need to ensure compatibility of the actual and coded medical records.