Citations

Abstract Purpose: Insulin-like growth factor (IGF)-I and IGF-II stimulate neoplastic cell growth and inhibit apoptosis, whereas IGF-binding protein-3 (IGFBP-3) inhibits the bioavailability of IGF-I and has independent proapoptotic activity. We examined the influence of baseline plasma levels of IGF-I, IGF-II, IGFBP-3, and C-peptide on outcome among patients receiving first-line chemotherapy for metastatic colorectal cancer. Experimental Design: The plasma levels of IGF-I, IGF-II, IGFBP-3, and C-peptide as well as data on prognostic factors and body size were measured at baseline among 527 patients participating in a randomized trial of first-line chemotherapy for metastatic colorectal cancer. Results: Higher baseline plasma IGFBP-3 levels were associated with a significantly greater chemotherapy response rate (P = 0.03) after adjusting for other prognostic factors, whereas neither IGF-I nor IGF-II levels significantly predicted tumor response. Higher levels of IGF-I, IGF-II, and IGFBP-3 were all univariately associated with improved overall survival (P = 0.0001 for all). In a model that mutually adjusted for IGF-I and IGFBP-3, as well as other prognostic factors, increasing baseline-circulating IGFBP-3 was associated with a significantly longer time to tumor progression (P = 0.03), whereas circulating IGF-I was not associated with disease progression (P = 0.95). Levels of C-peptide were not associated with any measure of patient outcome. Conclusion: Among colorectal cancer patients receiving first-line chemotherapy, increasing levels of IGFBP-3, an endogenous antagonist to IGF-I, are associated with an improved objective treatment response and a prolonged time to cancer progression. The IGF pathway may represent an important target for future treatment strategies.

AbstractDo some patients benefit from an unrelated donor (URD) transplant because of a stronger graft-versus-leukemia (GVL) effect? We analyzed 4099 patients with acute myeloid leukemia (AML), acute lymphoblastic leukemia (ALL), and chronic myeloid leukemia (CML) undergoing a myeloablative allogeneic hematopoietic cell transplantation (HCT) from an URD (8/8 human leukocyte antigen [HLA]–matched, n = 941) or HLA-identical sibling donor (n = 3158) between 1995 and 2004 reported to the CIBMTR. In the Cox regression model, acute and chronic GVHD were added as time-dependent variables. In multivariate analysis, URD transplant recipients had a higher risk for transplantation-related mortality (TRM; relative risk [RR], 2.76; P < .001) and relapse (RR, 1.50; P < .002) in patients with AML, but not ALL or CML. Chronic GVHD was associated with a lower relapse risk in all diagnoses. Leukemia-free survival (LFS) was decreased in patients with AML without acute GVHD receiving a URD transplant (RR, 2.02; P < .001) but was comparable to those receiving HLA-identical sibling transplants in patients with ALL and CML. In patients without GVHD, multivariate analysis showed similar risk of relapse but decreased LFS for URD transplants for all 3 diagnoses. In conclusion, risk of relapse was the same (ALL, CML) or worse (AML) in URD transplant recipients compared with HLA-identical sibling transplant recipients, suggesting a similar GVL effect.

Purpose Obesity is a risk factor for the development of colon cancer. However, the influence of body mass index (BMI) on the outcome of patients with established colon cancer remains uncertain. Moreover, the impact of change in body habitus after diagnosis has not been studied. Patients and Methods We conducted a prospective, observational study of 1,053 patients who had stage III colon cancer and who were enrolled on a randomized trial of adjuvant chemotherapy. Patients reported on height and weight during and 6 months after adjuvant chemotherapy. Patients were observed for cancer recurrence or death. Results In this cohort of patients with stage III cancer, 35% of patients were overweight (BMI, 25 to 29.9 kg/m2), and 34% were obese (BMI ≥ 30 kg/m2). Increased BMI was not significantly associated with a higher risk of colon cancer recurrence or death (P trend = .54). Compared with normal-weight patients (BMI, 21 to 24.9 kg/m2), the multivariate hazard ratio for disease-free survival was 1.00 (95% CI, 0.72 to 1.40) for patients with class I obesity (BMI, 30 to 34.9 kg/m2) and 1.24 (95% CI, 0.84 to 1.83) for those with class II to III obesity (BMI ≥ 35 kg/m2) after analysis was adjusted for tumor-related prognostic factors, physical activity, tobacco history, performance status, age, and sex. Similarly, after analysis was controlled for BMI, weight change (either loss or gain) during the time period between ongoing adjuvant therapy and 6 months after completion of therapy did not significantly impact on cancer recurrence and/or mortality. Conclusion Neither BMI nor weight change was significantly associated with an increased risk of cancer recurrence and death in patients with colon cancer.

Abstract Background: The International Lung Cancer Consortium was established in 2004. To clarify the role of DNA repair genes in lung cancer susceptibility, we conducted a pooled analysis of genetic variants in DNA repair pathways, whose associations have been investigated by at least 3 individual studies. Methods: Data from 14 studies were pooled for 18 sequence variants in 12 DNA repair genes, including APEX1, OGG1, XRCC1, XRCC2, XRCC3, ERCC1, XPD, XPF, XPG, XPA, MGMT, and TP53. The total number of subjects included in the analysis for each variant ranged from 2,073 to 13,955 subjects. Results: Four of the variants were found to be weakly associated with lung cancer risk with borderline significance: these were XRCC3 T241M [heterozygote odds ratio (OR), 0.89; 95% confidence interval (95% CI), 0.79-0.99 and homozygote OR, 0.84; 95% CI, 0.71-1.00] based on 3,467 cases and 5,021 controls from 8 studies, XPD K751Q (heterozygote OR, 0.99; 95% CI, 0.89-1.10 and homozygote OR, 1.19; 95% CI, 1.02-1.39) based on 6,463 cases and 6,603 controls from 9 studies, and TP53 R72P (heterozygote OR, 1.14; 95% CI, 1.00-1.29 and homozygote OR, 1.20; 95% CI, 1.02-1.42) based on 3,610 cases and 5,293 controls from 6 studies. OGG1 S326C homozygote was suggested to be associated with lung cancer risk in Caucasians (homozygote OR, 1.34; 95% CI, 1.01-1.79) based on 2,569 cases and 4,178 controls from 4 studies but not in Asians. The other 14 variants did not exhibit main effects on lung cancer risk. Discussion: In addition to data pooling, future priorities of International Lung Cancer Consortium include coordinated genotyping and multistage validation for ongoing genome-wide association studies. (Cancer Epidemiol Biomarkers Prev 2008;17(11):3081–9)

Purpose The combination of doxorubicin and cyclophosphamide (AC) is a standard adjuvant regimen. Doxorubicin and docetaxel (AT) is one of the most active cytotoxic regimens for metastatic breast cancer. The purpose of this trial was to determine whether adjuvant AT improved disease-free survival compared with AC in operable breast cancer. Patients and Methods Women with invasive breast cancer were eligible if there were one to three positive lymph nodes or if the node-negative tumor was greater than 1 cm. Patients were randomly assigned after surgery to receive doxorubicin (60 mg/m2) plus either cyclophosphamide (600 mg/m2; AC) or docetaxel (60 mg/m2; AT) given every 3 weeks for four cycles, followed by hormone therapy for patients with estrogen receptor (ER) and/or progesterone receptor (PR)–positive tumors. Results There were 2,882 eligible patients enrolled. After a median follow-up of 79.5 months, there was no significant difference in disease-free survival (DFS; 85% in both arms) or overall survival (91% v 92%) at 5 years. The hazard ratio for AC versus AT was 1.02 (95% CI for DFS, 0.86 to 1.22; P = .78). In an exploratory analysis of prespecified stratification factors by ER and PR expression there were trends toward improved DFS for AT in ER/PR-negative disease. Grade 3 neutropenia associated with fever or infection occurred more often with AT (26% v 10%; P < .05). Conclusion AT did not improve DFS or overall survival in this population, and was associated with more toxicity.

AbstractImatinib mesylate (IM, Gleevec) has largely supplanted allogeneic hematopoietic cell transplantation (HCT) as first line therapy for chronic myeloid leukemia (CML). Nevertheless, many people with CML eventually undergo HCT, raising the question of whether prior IM therapy impacts HCT success. Data from the Center for International Blood and Marrow Transplant Research on 409 subjects treated with IM before HCT (IM+) and 900 subjects who did not receive IM before HCT (IM−) were analyzed. Among patients in first chronic phase, IM therapy before HCT was associated with better survival but no statistically significant differences in treatment-related mortality, relapse, and leukemia-free survival. Better HLA-matched donors, use of bone marrow, and transplantation within one year of diagnosis were also associated with better survival. A matched-pairs analysis was performed and confirmed a higher survival rate among first chronic phase patients receiving IM. Among patients transplanted with advanced CML, use of IM before HCT was not associated with treatment-related mortality, relapse, leukemia-free survival, or survival. Acute graft-versus-host disease rates were similar between IM+ and IM− groups regardless of leukemia phase. These results should be reassuring to patients receiving IM before HCT.

Object Thyroid-stimulating hormone (TSH)–secreting pituitary adenomas are rare, representing < 2% of all pituitary adenomas. Methods The authors conducted a retrospective analysis of patients with TSH-secreting or clinically silent TSH-immunostaining pituitary tumors among all pituitary adenomas followed at their institution between 1987 and 2003. Patient records, including clinical, imaging, and pathological and surgical characteristics were reviewed. Twenty-one patients (6 women and 15 men; mean age 46 years, range 26–73 years) were identified. Of these, 10 patients had a history of clinical hyperthyroidism, of whom 7 had undergone ablative thyroid procedures (thyroid surgery/131I ablation) prior to the diagnosis of pituitary adenoma. Ten patients had elevated TSH preoperatively. Seven patients presented with headache, and 8 presented with visual field defects. All patients underwent imaging, of which 19 were available for imaging review. Sixteen patients had macroadenomas. Results Of the 21 patients, 18 underwent transsphenoidal surgery at the authors' institution, 2 patients underwent transsphenoidal surgery at another facility, and 1 was treated medically. Patients with TSH-secreting tumors were defined as in remission after surgery if they had no residual adenoma on imaging and had biochemical evidence of hypo-or euthyroidism. Patients with TSH-immunostaining tumors were considered in remission if they had no residual tumor. Of these 18 patients, 9 (50%) were in remission following surgery. Seven patients had residual tumor; 2 of these patients underwent further transsphenoidal resection, 1 underwent a craniotomy, and 4 underwent postoperative radiation therapy (2 conventional radiation therapy, 1 Gamma Knife surgery, and 1 had both types of radiation treatment). Two patients had persistently elevated TSH levels despite the lack of evidence of residual tumor. On pathological analysis and immunostaining of the surgical specimen, 17 patients had samples that stained positively for TSH, 8 for α-subunit, 10 for growth hormone, 7 for prolactin, 2 for adrenocorticotrophic hormone, and 1 for follicle-stimulating hormone/luteinizing hormone. Eleven patients (61%) ultimately required thyroid hormone replacement therapy, and 5 (24%) required additional pituitary hormone replacement. Of these, 2 patients required treatment for new anterior pituitary dysfunction as a complication of surgery, and 2 patients with preoperative partial anterior pituitary dysfunction developed complete panhypopituitarism. One patient had transient diabetes insipidus. The remainder had no change in pituitary function from their preoperative state. Conclusions Thyroid-stimulating hormone–secreting pituitary lesions are often delayed in diagnosis, are frequently macroadenomas and plurihormonal in terms of their pathological characteristics, have a heterogeneous clinical picture, and are difficult to treat. An experienced team approach will optimize results in the management of these uncommon lesions.

AbstractLeukemia-cell expression of ZAP-70, CD38, or unmutated immunoglobulin heavy chain variable region genes (U-IGHV) each is associated with aggressive disease in patients with chronic lymphocytic leukemia (CLL). To assess the relative strength of each marker, we defined thresholds for designating a case as positive for CD38 or ZAP-70 in a test cohort of 307 patients and used these data-defined criteria to stratify patients in an independent cohort of 705 patients. Multivariable analysis revealed that ZAP-70 was the strongest risk factor. Knowledge of the IGHV mutation status or CD38 did not improve our ability to predict the time to first treatment except for ZAP-70–negative cases, which could be segregated into 2 groups of intermediate-risk or low-risk disease based on whether they expressed unmutated or mutated IGHV. ZAP-70 maintained its high relative prognostic value for the subset of patients with early-stage, asymptomatic disease, including patients evaluated within 1 year of diagnosis. Although it is premature to recommend therapy based on these risk factors, patients with ZAP-70–positive CLL cells should be monitored closely for disease progression as they have a median time from diagnosis to requiring initial therapy by standard criteria of approximately 3 years.

Eps15 (EGFR pathway substrate clone 15) is well known for its role in clathrin-coated vesicle formation at the plasma membrane through interactions with other clathrin adaptor proteins such as AP-2. Interestingly, we observed that in addition to its plasma membrane localization, Eps15 is also present at the trans-Golgi network (TGN). Therefore, we predicted that Eps15 might associate with clathrin adaptor proteins at the TGN and thereby mediate the formation of Golgi-derived vesicles. Indeed, we have found that Eps15 and the TGN clathrin adaptor AP-1 coimmunoprecipitate from rat liver Golgi fractions. Furthermore, we have identified a 14-amino acid motif near the AP-2–binding domain of Eps15 that is required for binding to AP-1, but not AP-2. Disruption of the Eps15–AP-1 interaction via siRNA knockdown of AP-1 or expression of mutant Eps15 protein, which lacks a 14-amino acid motif representing the AP-1 binding site of Eps15, significantly reduced the exit of secretory proteins from the TGN. Together, these findings indicate that Eps15 plays an important role in clathrin-coated vesicle formation not only at the plasma membrane but also at the TGN during the secretory process.