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Purpose: To determine the analgesic effect of the addition of gabapentin to opioids in the management of neuropathic cancer pain., Patients and Methods: One hundred twenty-one consecutive patients with neuropathic pain due to cancer, partially controlled with systemic opioids, participated in a multicenter, randomized, double-blind, placebo-controlled, parallel-design, 10-day trial from August 1999 to May 2002. Gabapentin was titrated from 600 mg/d to 1,800 mg/d in addition to stable opioid dose. Extra opioid doses were available as needed. Zero to 10 numerical scale was used to rate average daily pain. The average pain score over the whole follow-up period was used as main outcome measure. Secondary outcome measures were: intensity of burning pain, shooting/lancinating pain, dysesthesias (also scored on 0 to 10 numerical scale), number of daily episodes of lancinating pain, presence of allodynia, and daily extra doses of opioid analgesics., Results: Overall, 79 patients received gabapentin and 58 (73%) completed the study; 41 patients received placebo and 31 (76%) completed the study. Analysis of covariance (ANCOVA) on the intent-to-treat population showed a significant difference of average pain intensity between gabapentin (pain score, 4.6) and placebo group (pain score, 5.4; P =.0250). Among secondary outcome measures, dysesthesia score showed a statistically significant difference (P =.0077; ANCOVA on modified intent-to-treat population = 115 patients with at least 3 days of pain assessments). Reasons for withdrawing patients from the trial were adverse events in six patients (7.6%) receiving gabapentin and in three patients receiving placebo (7.3%)., Conclusion: Gabapentin is effective in improving analgesia in patients with neuropathic cancer pain already treated with opioids.

Spirohydantoin mustard (spiromustine, NSC 172112) is a classical bifunctional alkylating agent synthesized in an effort to develop antitumor agents effective against CNS tumors. The rationale was to combine the reactive moiety of an active antitumor agent with the hydantoin part of the molecule, which might serve as a carrier to cross the blood brain barrier. Thirty-eight patients with refractory solid tumors received spiromustine as part of a phase I trial at the Johns Hopkins Oncology Center. Three schedules were investigated: intravenously (IV) daily for three consecutive days, IV every other day for 3 days, and IV on a weekly basis for three doses, all cycled every 28 days. Hematologic toxicity was infrequently seen. Mild to moderate nausea and vomiting occurred on all schedules. The dose limiting toxicity was CNS toxicity characterized by mydriasis, xerostomia, lethargy, confusion, and hallucinations. This CNS toxicity was dose related, cumulative, and reversible. IV physostigmine appeared to diminish the neurotoxicity if administered before spiromustine and at frequent intervals following the drug. The maximum tolerated dose of spiromustine (without concomitant physostigmine) on the three times a week schedule is 6 mg/m2. With physostigmine pretreatment, 8 mg/m2 can be administered. The three times daily and every other day for three days schedules are not recommended for further study due to the severity of neurotoxicity. It is recommended that 6 mg/m2 be used as the starting dose for any phase II studies using the three times weekly schedule, and that physostigmine be used as needed to minimize neurotoxicity. Dose escalation above this level can be considered when individual tolerance has been established. Phase II trials to investigate the activity of this agent against primary and metastatic CNS malignancies appear indicated on the basis of three transient radiographic responses in refractory malignancies metastatic to the CNS.

A retrospective analysis of the University of Minnesota (Minneapolis) experience with retinoblastoma is presented. Seventy-five patients were diagnosed with retinoblastoma between 1958 and 1983, of which 53 (71%) had at least one Reese-Ellsworth group V eye. Nineteen group V patients and one group II patient developed extraocular disease recurrence. The cumulative actuarial rate of recurrence at 12 years was 36% for patients with group V disease. The median time from diagnosis to recurrence for unilateral patients was seven months and for bilateral patients 28 months (P = .001). Patients developing extraocular disease had a 10-year actuarial survival rate postrecurrence of 34%. The four long-term survivors of extraocular recurrences had had isolated orbital or local soft tissue recurrences only. Features of group V patients associated with extraocular recurrences were identified by univariate life table analyses. Clinical poor-risk factors included the nongenetic form of the disease (P = .03) and male sex (P = .02). Pathologic poor risk factors included rubeosis (P = .01), undifferentiated histology (P = .03), large tumor size (P = .05), and intraocular extension to the anterior segment (P = .02), retinal pigment epithelium (P = .03), choroid (P less than .001), and optic nerve beyond the lamina cribrosa (P = .02). Treatment-associated poor-risk factors included an optic nerve length of less than 5 mm removed at enucleation (P = .003). Multivariate life table analyses demonstrated the following parameters to be independent poor-prognostic factors: optic nerve length of less than 5 mm removed at enucleation (P = .001), optic nerve involvement (P = .004), and large tumor size (P = .01). These results will help to identify patients with retinoblastoma who are at greatest risk for extraocular recurrence.