Soluble P-selectin glycoprotein ligand 1 inhibits ocular inflammation in a murine model of allergy

PURPOSE

To assess the anti-inflammatory modality of a soluble extracellular form of P-selectin glycoprotein ligand 1 (sPSGL-1) in a mouse model of ocular allergic response.

METHODS

Potential anti-inflammatory effects of sPSGL-1 were investigated in SWR/J mice sensitized by topical application of short ragweed pollen to the nasal mucosa followed by a challenge of the ocular mucosa with the same allergen. Five experimental groups were included in these studies: A, mice neither sensitized nor challenged with pollen (control group 1); B, animals sensitized but not challenged (control group 2); C, animals not sensitized but challenged (control group 3); D, animals sensitized and challenged; and E, sensitized animals treated with sPSGL-1 before pollen challenge. All experimental groups were evaluated for gross morphologic ocular changes, and histologic assessments were made to determine the onset/progression of inflammatory reactions and to look for evidence of eosinophil infiltration.

RESULTS

Mice sensitized and challenged with pollen developed clinical signs consistent with human allergic conjunctivitis. These signs correlate with histologic changes in the conjunctival epithelium and stroma (e.g., edema and extensive eosinophil infiltration). Moreover, the ocular changes also correlated with evidence of eosinophil degranulation. However, sensitized and challenged mice concurrently treated with sPSGL-1 displayed no inflammatory ocular changes associated with a ragweed-induced type-1 hypersensitivity reaction. The lack of ocular changes included the absence of histologic late-phase inflammatory changes of the conjunctiva and a 97% reduction in the induced eosinophil infiltrate.

CONCLUSIONS

The antagonistic intervention of cell- cell interactions through the blockade of selectin-dependent leukocyte adhesion may offer novel therapeutic strategies to modulate inflammatory responses. The potent inhibitory effects on eosinophil recruitment and late-phase inflammation suggest a role for sPSGL-1 in the treatment of ocular allergic diseases.

Monitoring spinal cord motor and somatosensory evoked potentials in anesthetized primates

Monitoring Motor Evoked Potential (MEP) to Transcranial Stimulation (TMS) monitoring (MEP) is a growing technique to assess motor function under anesthesia. The following primate study was conducted to analyze the non-myogenic spinal motor and sensory volleys and to examine their reproducibility under nitrous oxide-methohexidone anesthesia. The traveling periodic spinal descending MEP to TMS and ascending somatosensory (SEP) to posterior tibial nerve stimulation across the thoracic cord were recorded in 12 cynomolgus monkeys. Through a small T11-T12 laminotomy, an insulated stainless steel electrode was inserted into the epidural thoracic space. The potentials were analyzed under 50 vol% NO in O2 with methohexital (0.1-0.2 mg kg-1 min-1). A well-defined periodic TMS-MEPs and PTN-SEPs were recorded with high reproducibility and consistency in repeated trials under N2O-methohexital anesthesia. MEP tracing consisted of an initial peak (direct (D) wave), occurring at 2.43 (+/- 0.28) msec followed by subsequent five positive (indirect (I) waves). Spinal SEPs-MEPs were clearly defined, morphologically stable, and consistent over time under N2O-methohexitone anesthesia. The present primate study may set a model to monitor both modalities in anesthetized neurosurgical patients.

Accrual strategies for phase I trials with delayed patient outcome

Phase I dose-finding trials typically are conducted using adaptive rules that select dose levels for successive patient cohorts based on the outcomes of patients treated previously in the trial. When patient outcome cannot be observed immediately after treatment, the problem arises of how to deal with new patients while waiting to observe the current patient cohort's outcomes. We consider two alternative approaches to this problem in the context of a phase I trial conducted using the continual reassessment method. With the first approach, a patient requiring treatment before the next cohort opens is treated off protocol with standard therapy, and otherwise waits until the next cohort opens. The second approach treats each patient immediately upon arrival at the dose recommended based on currently available data. We compare these two approaches by simulation under varying dose--toxicity curves, accrual rates, cohort sizes and early stopping rules. We evaluate patient waiting time, trial duration, number of patients treated off protocol and the probabilities of toxicity and of selecting the correct dose. We also study three strategies for assigning patients to trials when two or more phase I trials may be ongoing simultaneously. Based on our results, we provide practical guidelines for deciding among these approaches and strategies in a given clinical setting.

Modified-peptide inhibitors of amyloid beta-peptide polymerization

Cellular toxicity resulting from nucleation-dependent polymerization of amyloid beta-peptide (Abeta) is considered to be a major and possibly the primary component of Alzheimer's disease (AD). Inhibition of Abeta polymerization has thus been identified as a target for the development of therapeutic agents for the treatment of AD. The intrinsic affinity of Abeta for itself suggested that Abeta-specific interactions could be adapted to the development of compounds that would bind to Abeta and prevent it from polymerizing. Abeta-derived peptides of fifteen residues were found to be inhibitory of Abeta polymerization. The activity of these peptides was subsequently enhanced through modification of their amino termini with specific organic reagents. Additional series of compounds prepared to probe structural requirements for activity allowed reduction of the size of the inhibitors and optimization of the Abeta-derived peptide portion to afford a lead compound, cholyl-Leu-Val-Phe-Phe-Ala-OH (PPI-368), with potent polymerization inhibitory activity but limited biochemical stability. The corresponding all-D-amino acyl analogue peptide acid (PPI-433) and amide (PPI-457) retained inhibitory activity and were both stable in monkey cerebrospinal fluid for 24 h.

Adenovirus-mediated p53 gene transfer in advanced non-small-cell lung cancer

BACKGROUND

Preclinical studies in animal models have demonstrated tumor regression following intratumoral administration of an adenovirus vector containing wild-type p53 complementary DNA (Ad-p53). Therefore, in a phase I clinical trial, we administered Ad-p53 to 28 patients with non-small-cell lung cancer (NSCLC) whose cancers had progressed on conventional treatments.

METHODS

Patients received up to six, monthly intratumoral injections of Ad-p53 by use of computed tomography-guided percutaneous fine-needle injection (23 patients) or bronchoscopy (five patients). The doses ranged from 10(6) plaque-forming units (PFU) to 10(11) PFU.

RESULTS

Polymerase chain reaction (PCR) analysis showed the presence of adenovirus vector DNA in 18 (86%) of 21 patients with evaluable posttreatment biopsy specimens; vector-specific p53 messenger RNA was detected by means of reverse transcription-PCR analysis in 12 (46%) of 26 patients. Apoptosis (programmed cell death) was demonstrated by increased terminal deoxynucleotide transferase-mediated biotin uridine triphosphate nick-end labeling (TUNEL) staining in posttreatment biopsy specimens from 11 patients. Vector-related toxicity was minimal (National Cancer Institute's Common Toxicity Criteria: grade 3 = one patient; grade 4 = no patients) in 84 courses of treatment, despite repeated injections (up to six) in 23 patients. Therapeutic activity in 25 evaluable patients included partial responses in two patients (8%) and disease stabilization (range, 2-14 months) in 16 patients (64%); the remaining seven patients (28%) exhibited disease progression.

CONCLUSIONS

Repeated intratumoral injections of Ad-p53 appear to be well tolerated, result in transgene expression of wild-type p53, and seem to mediate antitumor activity in a subset of patients with advanced NSCLC.

Anti-CD86 (B7.2) treatment abolishes allergic airway hyperresponsiveness in mice

Allergic sensitization in asthma develops as a consequence of complex interactions between T cells and antigen-presenting cells. We have developed several in vivo models to study allergen-specific T cell and B cell function and their relevance to allergic airway hyperresponsiveness (AHR), focusing on the role of the costimulatory molecules CD80 and CD86. Treatment of mice with anti-CD86, but not anti-CD80, significantly inhibited increased serum levels of ovalbumin (OA)-specific IgE and IgG1, airway eosinophilia, and AHR both after 10 d of OA aerosol exposure (in the absence of adjuvant) and after intraperitoneal sensitization followed by repeated airway challenges. Inhibition of AHR was associated with decreased IL-4 and IL-5 levels in the BAL fluid of sensitized mice, suggesting impaired Th2 function in anti-CD86-treated animals. This effect was not seen when mice received treatment only before allergen challenge, indicating that anti-CD86 acts through inhibition of allergic sensitization and not simply by inhibiting the influx of inflammatory cells. These data suggest that the CD86 costimulatory ligand plays a major role in the development of allergic inflammation and AHR in allergen-challenged mice. Further, this study demonstrates that T-B cell interactions during allergic sensitization are amenable to therapeutic manipulation and that selective blockade of accessory signals can be an effective means for modulating distinct T cell functions.

Comparisons of prognostic scoring systems for myelodysplastic syndromes: a Korean multicenter study

We have conducted a multicenter collaborative retrospective analysis to evaluate clinical characteristics and to compare prognostic scoring systems of 149 Korean patients with myelodysplastic syndromes (MDS). The median age of the patients was 53 years (range 17-82 years) with high of the patients being younger than 40 years. Median survival was 22.6 months, and 25 patients (17%) progressed to acute myelogenous leukemia (AML) with a median interval of 6 months (range 1-45 months). Major independent variables assessed by multivariate analysis were FAB subtypes and bone marrow (BM) blast percentages for survival and BM blast percentages for AML transformation. To compare the various scoring systems in the prediction for survival and transformation to AML, FAB, Sanz and Bournemouth scoring systems were applied to all patients, while the international prognostic scoring system (IPSS), Lille and Toyama scoring systems were applied to 91 patients. The Sanz scoring system (P < 0.0001), FAB classification (P < 0.0001), IPSS (P < 0.001), and Toyama scoring system (P < 0.005) were highly predictive for survival showed greater discrimination than that of the other systems. For AML transformation, the IPSS (P < 0.0001), Toyama scoring system (P < 0.0001), FAB classification (P < 0.0001), and Lille scoring system (P < 0.005) successfully discriminated risk groups. Although the prognostic factors and the distribution of age were different from those in Western reports, the IPSS and Toyama scoring system were applicable for predicting survival and leukemic transformation in Korean patients with MDS.

Sesquiterpene esters from Celastrus orbiculatus and their structure-activity relationship on the modulation of multidrug resistance

Six new (1-6) and three known (7-9) sesquiterpene esters were isolated from the roots of Celastrus orbiculatus. The structures of the new compounds were elucidated as 1beta-acetoxy-6alpha-furoyloxy-9alpha-benzoyl oxydihydro-beta-agarofur an (1), 1beta-acetoxy-6alpha-benzoyloxy-9alpha-furoyloxydih ydro-beta-agarofur an (2), 1beta-acetoxy-6alpha, 9alpha-difuroyloxydihydro-beta-agarofuran (3), 1beta, 2beta-diacetoxy-6alpha-furoyloxy-9alpha-benzo yloxydihydro-beta-agarof uran (4), 1beta-acetoxy-2beta, 6alpha-difuroyloxy-9alpha-benzoyloxydihydro-beta -agarofuran (5), and 1beta-acetoxy-2beta,6alpha, 9alpha-tribenzoyloxydihydro-beta-agarofuran (6). Compounds 4, 5, and 7-9 were shown to be more active than verapamil in reversing vinblastine resistance in multidrug-resistant KB-V1 cells.

Pregnane glycoside multidrug-resistance modulators from Cynanchum wilfordii

The methanol-soluble extracts of the roots of Cynanchum wilfordii showed a significant multidrug-resistance-reversing activity, and four known pregnane glycosides were isolated by bioassay-directed fractionation and separation. Their structures were identified as gagaminin 3-O-beta-D-cymaropyranosyl-(1-->4)-beta-D-oleandropyranosyl- (1-->4)-b eta-D-cymaropyranosyl-(1-->4)-beta-D-cymaropyranoside (1), wilfoside K1N (2), wilfoside C1N (3), and cynauricuoside A (4). In particular, compound 1, at a concentration level of 1 microM, was found to completely reverse the multidrug-resistance of KB-V1 and MCF7/ADR cells to adriamycin, vinblastine, and colchicine.

Bcl-2 and p53 expressions in invasive bladder cancers

We investigated the Bcl-2 and P53 protein expressions in 89 patients with bladder cancers using immunohistochemical analysis. In superficial tumors, the times of tumor recurrence and progression were significantly shorter in the P53-positive group than in the negative group (p < 0.005, p < 0.05, respectively). In invasive tumors, the disease-specific actuarial survivals were significantly lower in the P53 and Bcl-2-positive groups (p <0.05, p < 0.025, respectively). In multivariate analysis, overexpression of p53 and Bcl-2 had independent prognostic value for survivals in invasive tumor, while disease-free survival was related independently to overexpression of p53 in superficial tumor. The results of our assessment for chemoeffectiveness revealed that the patients with Bcl-2-positive tumors had significantly lower response rates than those with Bcl-2-negative tumors (p < 0.05). We conclude that p53 expression is an independent, poor prognostic marker in invasive tumors as well as in superficial tumors and that overexpression of Bcl-2 is independently associated with a reduced-survival in patients with invasive tumors. These prognostic differences related to P53 and Bcl-2 expression in invasive bladder cancers may be partly due to chemo- or radio-sensitivity in relation to apoptotic process.

Multi-institutional melanoma lymphatic mapping experience: the prognostic value of sentinel lymph node status in 612 stage I or II melanoma patients

PURPOSE

To compare the effect of pathologic sentinel lymph node (SLN) status with that of other known prognostic factors on recurrence and survival in patients with stage I or II cutaneous melanoma.

PATIENTS AND METHODS

We reviewed the records of 612 patients with primary cutaneous melanoma who underwent lymphatic mapping and SLN biopsy between January 1991 and May 1995 to determine the effects of tumor thickness, ulceration, Clark level, location, sex, and SLN pathologic status on disease-free and disease-specific survival.

RESULTS

In the 580 patients in whom lymphatic mapping and SLN biopsy were successful, the SLN was positive by conventional histology in 85 patients (15%) but negative in 495 patients (85%). SLN status was the most significant prognostic factor with respect to disease-free and disease-specific survival by univariate and multiple covariate analyses. Although tumor thickness and ulceration influenced survival in SLN-negative patients, they provided no additional prognostic information in SLN-positive patients.

CONCLUSION

Lymphatic mapping and SLN biopsy is highly accurate in staging nodal basins at risk for regional metastases in primary melanoma patients and identifies those who may benefit from earlier lymphadenectomy. Furthermore, pathologic status of the SLN in these patients with clinically negative nodes is the most important prognostic factor for recurrence. The information from SLN biopsy is particularly helpful in establishing stratification criteria for future adjuvant trials.

A male accessory gland protein that modulates female mosquito (Diptera: Culicidae) host-seeking behavior

The male accessory gland product that modulates the host-seeking behavior of female Aedes aegypti (L.) mosquitoes was found to be a peptide of 7,600 mw. This peptide also prevented subsequent mating behavior and weakly stimulated oviposition. Neither whole glands nor gland fractions from Anopheles gambiae had any effect on Ae. aegypti females, but those from Aedes albopictus were active.

Acetophenones from the roots of Cynanchum wilfordii H(EMSLEY)

Two acetophenones, cynandione A (1) and cynanchone A (2), were isolated from the roots of Cynanchum wilfordii. Their structures were identified by comparison of their physicochemical and spectral data with reported values.

Primary carcinoma of the gallbladder: results of surgery--a retrospective study

BACKGROUND

The development of hepatobiliary imaging modalities has resulted in earlier detection of gallbladder cancer. This is a retrospective evaluation of surgical resection of gallbladder cancer.

METHODS

Records of 58 patients with gallbladder carcinoma who underwent surgical resection in the past 14 years were examined. Patients were staged according to the Nevin system: six had Nevin stage I disease; 10, stage II; 9, stage III; four, stage IV; and 24 had stage V cancer. Forty-three patients were thought to have resectable lesions. Of these, 14 had extended cholecystectomy, 21 simple cholecystectomy, seven simple cholecystectomy with biliary drainage and one patient had radical cholecystectomy with pancreaticoduodenectomy. Prognoses were analyzed in relation to pathologic staging and surgical procedures.

RESULTS

The overall one-year and five-year survival rates were 50% and 19.2%, respectively. The five-year survival rate for Nevin stage I was 100%; for stage II, 60%; stage III, 33%; stage IV, 25% and for stage V, 0%. Radical surgery led to a better cumulative survival rate for Nevin stages III and IV (p < 0.01) than did simple cholecystectomy. Five Stage II cases were treated with simple cholecystectomy but two patients had early metastasis. Four stage III patients underwent simple cholecystectomy and three had metastasis within one year.

CONCLUSIONS

Based on these results, stage III and IV tumors require extended procedures for better survival. A high index of suspicion for the disease, careful intraoperative examination of the gallbladder specimen and earlier, more aggressive treatment may improve patient survival.

Iridoid compounds from Boschniakia rossica

Four iridoid compounds were isolated from methanol extract of Boschniakia rossica by repeated column chromatography. Their structures were determined as boschnaloside (1), boschnarol (2), bosnarol methylether (3), and 7-deoxy 8-epiloganic acid (4), respectively. Compound 2, 3, and 4 were isolated for the first time from this plant.

Phase II study of neoadjuvant concurrent biochemotherapy in melanoma patients with local-regional metastases

Our results with concurrent biochemotherapy in patients with stage IV melanoma have been encouraging. Based on these data, we conducted a phase II study to determine the clinical and histological response rate to neoadjuvant concurrent biochemotherapy in patients with local-regional metastases of cutaneous melanoma (stage III). A total of 65 patients with biopsy-proven, measurable and potentially resectable local-regional disease (nodal, satellite/in-transit metastases and/or local recurrence) were treated with cisplatin 20 mg/m2 intravenously (i.v.) on days 1 to 4, vinblastine 1.5 mg/m2 i.v. on days 1 to 4, dacarbazine 800 mg/m2 i.v. on day 1 only, interleukin-2 9 MIU/m2 per day i.v. by 96 h continuous infusion on days 1 to 4, and interferon-alpha 2a 5 MU/m2 subcutaneously on days 1 to 5, repeated every 3 weeks. Patients underwent surgery after two to four courses of biochemotherapy. Those with tumour regression after two preoperative courses received two additional postoperative courses. Of the 64 patients assessable for clinical response, 28 (44%) had a partial response. Of the 62 patients whose response was assessed histologically, four (6.5%) had no evidence of viable tumour in the surgical specimen (pathological complete remission, pCR) and 27 (43.5%) had a partial response, giving an overall response rate of 50%. Tumour burden did not correlate with response, although patients who achieved a pCR had a significantly lower tumour burden (P = 0.02). Our phase II study indicates that neoadjuvant biochemotherapy is an active treatment for melanoma patients with local-regional metastases. However, it is unclear if biochemotherapy is more active than chemotherapy alone; phase III randomized trials are ongoing to answer this question in patients with stage IV disease.

Percutaneous transluminal angioplasty for the treatment of limb threatening ischemia: do the results justify an attempt before bypass grafting?

PURPOSE

Results of percutaneous transluminal angioplasty (PTA) in selected cases have been reported to be equal or superior to those of arterial bypass graft surgery, with a lower morbidity and mortality. We performed PTA of stenotic or occlusive lesions in patients with limb-threatening ischemia, hoping to improve our overall success and decrease morbidity in this group of patients. The results of PTA in the limb-salvage setting was evaluated.

METHODS

From 1992 to 1995, 307 PTAs were performed in 257 patients. One hundred sixty-one (63%) patients had diabetes mellitus, and 32 (12%) patients had renal failure. All patients were evaluated by means of pulse volume recordings and ankle brachial indices at 1 and 6 weeks after PTA and at 3 month intervals thereafter. Seventeen patients (9%) were lost to follow-up. The continued success or failure of PTA was defined by means of noninvasive vascular laboratory criteria, patency by means of pulse examination, the need for subsequent bypass grafting across the index lesion, and limb salvage.

RESULTS

The 1-year patency rates for external iliac PTAs (56%) were significantly lower (P <.05) than those for common iliac PTAs (87%). Infrainguinal PTAs at the femoral, popliteal, and tibial level had 1-year patency rates of less than 15%.

CONCLUSION

Common iliac artery PTA is justified in most cases in which it is feasible. However, when PTAs are performed below the inguinal ligament, the results are markedly worse. One-year patency rates of PTA in this group of patients with threatened limbs are inferior to the patency rates of arterial bypass grafts, even when these bypasses are performed with a prosthetic material. PTA should not be considered as a primary treatment modality for patients with infrainguinal arterial occlusive disease who also have limb-threatening ischemia, except in unusual circumstances.

Anticomplementary activity of stilbenes from medicinal plants

The anticomplementary activity of stilbenes from medicinal plants in Korea was investigated in vitro. 3,5-Dihydroxy-4'-methoxystilbene (3) was most potent with IC50 value of 1.5 x 10(-4) M followed by rhapontigenin (4), oxyresverastrol (2), 2,3,4',5-tetrahydroxystilbene-2-O-beta-glucoside (9), rhaponticin (8), resverastrol (1), and piceid (7). The activity was found to be increased by a methylation on a hydroxy group of C-4' of 1, but decreased by further methylation on hydroxy groups of C-3 and C-5 and glucosylation on any hydroxy group of 1. Addition of hydroxy group on C-2' of 1 or C-3' of 3 was little affected on the anticomplementary activity but the activity was increased by O-glucosylation on C-2 of 1.

Phenotype and genotype of advanced premalignant head and neck lesions after chemopreventive therapy

BACKGROUND

The goal of chemoprevention is to reduce the risk of cancer development by reversing or blocking the tumorigenic process through the use of pharmacologic or natural agents. To determine the potential role of genetic alterations in assessing cancer risk and in evaluating the efficacy of chemopreventive agents, we studied 22 patients with advanced premalignant lesions of the head and neck who were part of a prospective cancer prevention trial that is investigating a regimen of 13-cis-retinoic acid, interferon alfa, and alpha-tocopherol administered for 12 months or until disease progression.

METHODS

We used polymerase chain reaction analysis of microsatellite DNA sequences in cells from precancerous lesions to determine the frequencies of genetic alterations--namely, loss of heterozygosity (LOH) and microsatellite instability--at chromosomal loci that are commonly deleted in head and neck cancer.

RESULTS

Prior to treatment, 17 (81%) of 21, eight (44%) of 18, and eight (42%) of 19 patients who were informative (i.e., heterozygous) at chromosomes 9p21, 3p14, and 17p13, respectively, exhibited LOH in at least one of their lesion biopsy specimens. Among nine patients who exhibited LOH at chromosome 9p21 in pretreatment biopsy specimens and who had completed at least 5 months of therapy, the genetic loss persisted in eight--including three of the four patients who exhibited complete histologic responses (i.e., no evidence of dysplasia in their biopsy specimens).

IMPLICATION

Our data suggest that clinical and histologic assessments of the response to chemopreventive agents may be insufficient to determine their efficacy and that critical genetic alterations could be used as independent biomarkers to augment the ability to evaluate the efficacy of such agents.

Anti-complement activity of tiliroside from the flower buds of Magnolia fargesii

As part of the search for anticomplementary active components from natural products, the anticomplementary properties of methanolic extracts from the flower buds of Magnoliafargesii have been investigated. Bioassay-guided chromatographic separation of the active constituents led to the isolation of compound 1, whose structure was identified by spectroscopic methods to be kaempferol 3-O-beta-D-(6"-O-coumaroyl)glucopyranoside (tiliroside). Tiliroside showed very potent anti-complement activity (IC50=5.4 x 10(-5) M) on the classical pathway of the complement system, even higher than rosmarinic acid, which is a well-known inhibitor against the complement system. On the other hand, the hydrolysates of tiliroside, kaempferol, astragalin and p-coumaric acid showed very weak activity on this system.

Acute hemolytic crisis with fulminant hepatic failure as the first manifestation of Wilson's disease: a case report

We report a 27-year-old woman who developed Coombs' negative hemolytic anemia and fulminant hepatic failure as the initial manifestation of Wilson's disease. Unmeasurably low level of serum alkaline phosphatase provided a clue to the diagnosis of Wilson's disease. The diagnosis was established with the presence of Kayser-Fleischer ring, decreased serum ceruloplasmin level, and elevated urine and serum copper levels. In spite of repeated plasmapheresis, she died of multiorgan failure on the fifth hospital day.

Benzo[a]pyrene diol epoxide and bleomycin sensitivity and susceptibility to cancer of upper aerodigestive tract

BACKGROUND

Tobacco smoking is an established risk factor for cancers of the upper aerodigestive tract, and measurement of chromosomal aberrations, i.e., chromatid breaks, induced in lymphocytes in vitro by bleomycin has been shown to be a predictor of risk for these cancers. In a case-control study, we recruited case subjects who were previously treated with surgery and/or radiotherapy for stage I or stage II squamous cell carcinoma of the head and neck to test the hypothesis that lymphocytic chromatid breaks induced by benzo[a]pyrene diol epoxide (BPDE), a tobacco mutagen, may also be associated with risk of developing cancers of the upper aerodigestive tract.

METHODS

Case subjects were matched to control subjects on the basis of age, sex, ethnicity, and smoking status. Primary lymphocytes from 67 case subjects and 81 control subjects were treated with 2 microM BPDE for 24 hours, and the frequency of induced chromatid breaks was determined. All statistical tests were two-sided.

RESULTS

Lymphocytes from case subjects compared with lymphocytes from control subjects showed significantly more breaks per cell induced by BPDE (mean+/-standard deviation, 0.77+/-0.38 versus 0.49+/-0.25; P<.001). Lymphocytes from 64.2% of case subjects were sensitive to BPDE (using a cutoff value of > or =0.60 break per cell). Subjects in the highest quartile of chromatid breaks had an approximately 20-fold increased risk of cancer compared with those in the lowest quartile after adjustment for age, sex, ethnicity, and smoking status. The association between BPDE sensitivity and cancer risk was higher in former smokers than in current smokers and higher in younger patients than in older patients. Subjects with sensitivity to both BPDE and bleomycin were at a 19.2-fold increased risk of cancer compared with those who were not sensitive to either agent.

CONCLUSIONS

Mutagen sensitivity assays may aid in identifying individuals at risk of cancer, and use of parallel assays with two mutagens may improve risk predictability.

Improved sentinel lymph node localization in patients with primary melanoma with the use of radiolabeled colloid

BACKGROUND

The purpose of this study was to determine whether the sentinel lymph node (SLN) localization technique, which uses blue dye and 99mTc-labeled sulfur colloid, provides advantages over blue dye alone in the management of patients with stages I and II cutaneous melanoma.

METHODS

The records of 626 consecutive patients with melanoma who underwent lymphatic mapping and SLN biopsy between 1991 and 1997 at the M.D. Anderson Cancer Center were reviewed. Lymphatic mapping was performed with isosulfan blue dye alone (n = 252) or in combination with 99mTc-labeled sulfur colloid accompanied by a hand-held gamma probe (n = 374). SLNs were defined as those that stained blue or demonstrated increased focal radiotracer uptake.

RESULTS

SLN identification rates improved from 87% (dye alone) to 99% (dye and colloid) (P < .0001) with the combined technique in all anatomic sites examined. The mean number of SLNs harvested from each basin was significantly greater in the patients mapped with dye and colloid (1.74 vs 1.31; P < .0001). Occult metastatic disease was identified in 17.5% of all patients and did not significantly differ between groups. In 92% of patients who had at least one positive SLN and were mapped with both agents, lymphatic metastases were identified in the SLN that contained the greatest radiotracer uptake.

CONCLUSIONS

SLN identification is enhanced by the addition of radiolabeled sulfur colloid and intraoperative use of the hand-held gamma probe and may identify SLNs missed by the blue dye alone. These data support the combined use of radiolabeled sulfur colloid and blue dye in lymphatic mapping procedures to improve the nodal staging of stages I and II melanoma.