Robert A. Lustig

Hypoxia is important in the biology and aggression of human glial brain tumors.

We investigated whether increasing levels of tissue hypoxia, measured by the binding of EF5 [2-(2-nitro-1-H-imidazol-1-yl)-N-(2,2,3,3,3-pentafluoropropyl) acetamide] or by Eppendorf needle electrodes, were associated with tumor aggressiveness in patients with previously untreated glial brain tumors. We hypothesized that more extensive and severe hypoxia would be present in tumor cells from patients bearing more clinically aggressive tumors. Hypoxia was measured with the 2-nitroimidazole imaging agent EF5 in 18 patients with supratentorial glial neoplasms. In 12 patients, needle electrode measurements were made intraoperatively. Time to recurrence was used as an indicator of tumor aggression and was analyzed as a function of EF5 binding, electrode values and recursive partitioning analysis (RPA) classification. On the basis of EF5 binding, WHO grade 2 tumors were characterized by modest cellular hypoxia (pO2s ≈ 10%) and grade 3 tumors by modest-to-moderate hypoxia (pO2s ≈ 10%- 2.5%). Severe hypoxia (≈0.1% oxygen) was present in 5 of 12 grade 4 tumors. A correlation between more rapid tumor recurrence and hypoxia was demonstrated with EF5 binding, but this relationship was not predicted by Eppendorf measurements.

The effect of fraction size on control of early glottic cancer

A retrospective analysis of 600 patients treated for head and neck malignancy at the Cooper Hospital/University Medical Center was undertaken. Patients who had surgical intervention (excluding biopsy) were withdrawn from this review. Fifty-eight patients with Stage I Glottic Laryngeal Carcinoma were identified and constitute the basis of this report. Various parameters were analyzed to assess their impact on local control. These include age, sex, serum hemoglobin, tumor bulk, differentiation, field size, total dose, total treatment time, and fraction size. Overall local control was 87% with a median follow-up of 63 months. The only factor that influenced local control was fraction size. Of 28 patients treated with 180 cGy fractions, seven (25%) had a local recurrence within 3 years. Twenty-eight patients treated with 200 cGy or greater fractions have had no failures to date. The difference in control rate when comparing the two treatment schema was significant (p less than 0.01). The median dose in the controlled 180 cGy group was 6660 cGy (range, 6300-7020 cGy). In the patients who failed in the 180 cGy group the median dose was 6660 cGy (range, 6480-6840 cGy). The patients receiving 200 cGy fractions or greater had a median dose of 6600 cGy (range, 6000-6950 cGy) and an average dose of 6507 cGy. The mean NSD in the 180 cGy group failing was 1787 RET (range, 1735-1843 RET). Patients who were controlled and received 180 cGy fractions had a median NSD of 1796 RET (range, 1743-1868). The mean NSD in the 200 cGy group was 1847 RET. The median TDF in the 180 cGy group of patients controlled was 102. Those failing also had a TDF of 102 (range, 101-105). Patients receiving 200 cGy fractions or greater had a median TDF of 109. It appears from this data that fraction size is a highly significant factor in our ability to control glottic laryngeal cancer.

A Phase II Study of Gefitinib for Aggressive Cutaneous Squamous Cell Carcinoma of the Head and Neck

Purpose: To determine the disease control rate and toxicity of treating patients with aggressive cutaneous squamous cell carcinoma (CSCC) with neoadjuvant gefitinib. Experimental Design: A prospective phase II clinical trial evaluating neoadjuvant gefitinib given prior to standard treatment with surgery and/or radiotherapy. Patients with stable disease after one cycle received escalated doses. Patients who responded were given gefitinib during radiation therapy, as well as maintenance therapy after definitive treatment. We analyzed the correlation between epidermal growth factor receptor (EGFR) expression, mutation status, and gene copy number on available tissue samples and clinical response. Results: Twenty-three patients were accrued and 22 patients were evaluable for response prior to definitive local treatment; complete responses were attained by 18.2% of patients and partial responses by 27.3%. Grades 2 to 3 toxicities were observed in 59.1% of patients experiencing class-specific effects during induction therapy. After induction, 11.8% underwent surgery alone, 17.6% had definitive radiation, 11.8% were treated with radiation and concurrent gefitinib, and 47% had surgery with postoperative radiation and concurrent gefitinib. Median follow-up for the censored observations was 32 months. Two-year overall, disease-specific, and progression-free survival rates were 72.1%, 72.1%, and 63.6%, respectively. No EGFR-activating mutations were identified in tumor samples available from 10 patients. No associations between EGFR correlative studies and patient outcomes were identified. Conclusions: Gefitinib, in the neoadjuvant setting, was active and well tolerated in patients with aggressive CSCC and did not interfere with definitive treatment. In view of the 18% complete response rate we observed, EGFR tyrosine kinase inhibitors should be further explored in the treatment of aggressive CSCC. Clin Cancer Res; 18(5); 1435–46. ©2012 AACR.

Risk Factors for Postcraniotomy Surgical Site Infection after 1,3-Bis (2-Chloroethyl)-1-Nitrosourea (Gliadel) Wafer Placement

Gliadel wafers (1,3-bis [2-chloroethyl]-1-nitrosourea; Guilford Pharmaceuticals) are approved for the treatment of malignant gliomas; however, the incidence of and risk factors associated with infection with respect to this new technology are unknown. We identified 32 patients who received Gliadel wafers from December 1996 through October 1999. Nine patients (28%) developed >or=1 surgical site infection (SSI), which included 4 cases of brain abscess. All 3 patients who received vancomycin for surgical prophylaxis developed an SSI. In addition, multivariable analysis revealed an association between infection and a clinical diagnosis of depression. The National Nosocomial Infection Surveillance Surgical Site Index did not predict the onset of SSI after Gliadel wafer implantation. Patients who received a Gliadel wafer had a higher incidence of infection than previously has been reported, and additional studies are required to better quantify this risk and describe the epidemiology of such infections.

Detection of brain tumor cells in the peripheral blood by a telomerase promoter-based assay.

Blood tests to detect circulating tumor cells (CTC) offer great potential to monitor disease status, gauge prognosis, and guide treatment decisions for patients with cancer. For patients with brain tumors, such as aggressive glioblastoma multiforme, CTC assays are needed that do not rely on expression of cancer cell surface biomarkers like epithelial cell adhesion molecules that brain tumors tend to lack. Here, we describe a strategy to detect CTC based on telomerase activity, which is elevated in nearly all tumor cells but not normal cells. This strategy uses an adenoviral detection system that is shown to successfully detect CTC in patients with brain tumors. Clinical data suggest that this assay might assist interpretation of treatment response in patients receiving radiotherapy, for example, to differentiate pseudoprogression from true tumor progression. These results support further development of this assay as a generalized method to detect CTC in patients with cancer.

The patterns of care outcome studies: results of the national practice in carcinoma of the larynx

The Patterns of Care Study conducted a survey of patients with glottic and supraglottic carcinomas treated in 1973 and 1974. Patients for this study were randomly selected from all types of treatment facilities, including those with full and part-time therapists and large and small institutions. Detailed evaluation and treatment parameters were recorded for a total of 707 patients. Overall three-year recurrence free survival for glottic carcinoma was: Stage I, 90%; Stage II, 78%; Stage III, 65%; and Stage IV, 23%. For supraglottic carcinoma the rates are: Stage I 78%, Stage II, 60%, Stage III, 34% and Stage IV, 30%. The use of surgery in this study for advanced lesions varied among different departments. For advanced lesions, those treated with combined radiation and surgery had improved survival; this was also related to completeness of work-up and departmental equipment.

Long term responses with cetuximab therapy in glioblastoma multiforme

Glioblastoma multiforme (GBM) is responsible for most of the deaths associated with primary brain tumors. Standard treatment includes maximal surgical resection followed by chemotherapy and concomitant radiotherapy. Most patients, however, recur shortly after treatment. Second line treatment has little efficacy and the majority of patients die soon from the disease. Recent advances in molecular biology have implicated the epidermal growth factor receptor (EGFR) signaling pathways in the progression and resistance to standard therapies for GBM. This has prompted the evaluation of EGFR tyrosine- kinase inhibitors with encouraging results. Cetuximab is a monoclonal antibody targeted against the extracellular domain of the EGFR with activity against different tumor types, either alone or in combination with chemotherapy and/or radiation therapy. Here we describe three patients with recurrent, heavily-pretreated, EGFR expressing GBM who responded to treatment with single agent cetuximab.

Stereotactic radiosurgery to the resection bed for intracranial metastases and risk of leptomeningeal carcinomatosis

OBJECT Following resection of a brain metastasis, stereotactic radiosurgery (SRS) to the cavity is an emerging alternative to postoperative whole-brain radiation therapy (WBRT). This approach attempts to achieve local control without the neurocognitive risks associated with WBRT. The authors aimed to report the outcomes of a large patient cohort treated with this strategy. METHODS A retrospective review identified 91 patients without a history of WBRT who received Gamma Knife (GK) SRS to 96 metastasis resection cavities between 2007 and 2013. Patterns of intracranial control were examined in the 86 cases with post-GK imaging. Survival, local failure, and distant failure were estimated by the Kaplan-Meier method. Prognostic factors were tested by univariate (log-rank test) and multivariate (Cox proportional hazards model) analyses. RESULTS Common primary tumors were non-small cell lung (43%), melanoma (14%), and breast (13%). The cases were predominantly recursive partitioning analysis Class I (25%) or II (70%). Median preoperative metastasis diameter was 2.8 cm, and 82% of patients underwent gross-total resection. A median dose of 16 Gy was delivered to the 50% isodose line, encompassing a median treatment volume of 9.2 cm(3). Synchronous intact metastases were treated in addition to the resection bed in 43% of cases. Patients survived a median of 22.3 months from the time of GK. Local failure developed in 16 cavities, for a crude rate of 18% and 1-year actuarial local control of 81%. Preoperative metastasis diameter ≥ 3 cm and residual or recurrent tumor at the time of GK were associated with local failure (p = 0.04 and 0.008, respectively). Distant intracranial failure occurred in 55 cases (64%) at a median of 7.3 months from GK. Salvage therapies included WBRT and additional SRS in 33% and 31% of patients, respectively. Leptomeningeal carcinomatosis developed in 12 cases (14%) and was associated with breast histology and infratentorial cavities (p = 0.024 and 0.012, respectively). CONCLUSIONS This study bolsters the existing evidence for SRS to the resection bed. Local control rates are high, but patients with larger preoperative metastases or residual/recurrent tumor at the time of SRS are more likely to fail at the cavity. While most patients develop distant intracranial failure, an SRS approach spared or delayed WBRT in the majority of cases. The risk of leptomeningeal carcinomatosis does not appear to be elevated with this strategy.

Impact of initial quality control review on study outcome in lung and head/neck cancer studies—review of the radiation therapy oncology group experience

The Radiation Therapy Oncology Group (RTOG) initiated cooperative clinical trials in 1971. In 1978, RTOG developed a formalized program of Quality Control (QC) divided into initial and final phases. The initial review process consisted of two steps. The first phase of review is an evaluation performed by a radiation oncologist to verify treatment plan and field borders. The second portion of the initial review process originally consisted of dosimetry calculation verification based on machine data provided by the regional Radiological Physics Center and treatment planning data provided by the accessioning institution. Between 1978 and December 31, 1987, a total of 11,343 cases in 96 RTOG protocols, excluding particle studies, underwent initial review. Of this number, 2227 patients were entered in lung cancer studies and 1341 patients were entered in head/neck cancer studies. Initial review was carried out in 2089 (93.8%) of the lung cancer cases. Missing or delayed data accounted for 138 (6.2%) cases not reviewed initially. In head/neck cancer trials, 1251 (93.2%) received initial review and 90 (6.8%) did not. Our findings suggest that there are sharply defined but long lasting learning experiences involved in clinical trial participation. Consideration may be given to modifying the initial review process to use random sampling of cases accessioned by experienced investigators in ongoing clinical trials and to continuing the total case evaluation on all new studies and cases entered by inexperienced investigators or investigators/institutions with unsatisfactory performance. Recommendations regarding initial review of other sites will await evaluation of the impact of initial review on those sites.

Differentiating Tumor Progression from Pseudoprogression in Patients with Glioblastomas Using Diffusion Tensor Imaging and Dynamic Susceptibility Contrast MRI

BACKGROUND AND PURPOSE: Early assessment of treatment response is critical in patients with glioblastomas. A combination of DTI and DSC perfusion imaging parameters was evaluated to distinguish glioblastomas with true progression from mixed response and pseudoprogression. MATERIALS AND METHODS: Forty-one patients with glioblastomas exhibiting enhancing lesions within 6 months after completion of chemoradiation therapy were retrospectively studied. All patients underwent surgery after MR imaging and were histologically classified as having true progression (>75% tumor), mixed response (25%–75% tumor), or pseudoprogression (<25% tumor). Mean diffusivity, fractional anisotropy, linear anisotropy coefficient, planar anisotropy coefficient, spheric anisotropy coefficient, and maximum relative cerebral blood volume values were measured from the enhancing tissue. A multivariate logistic regression analysis was used to determine the best model for classification of true progression from mixed response or pseudoprogression. RESULTS: Significantly elevated maximum relative cerebral blood volume, fractional anisotropy, linear anisotropy coefficient, and planar anisotropy coefficient and decreased spheric anisotropy coefficient were observed in true progression compared with pseudoprogression (P < .05). There were also significant differences in maximum relative cerebral blood volume, fractional anisotropy, planar anisotropy coefficient, and spheric anisotropy coefficient measurements between mixed response and true progression groups. The best model to distinguish true progression from non–true progression (pseudoprogression and mixed) consisted of fractional anisotropy, linear anisotropy coefficient, and maximum relative cerebral blood volume, resulting in an area under the curve of 0.905. This model also differentiated true progression from mixed response with an area under the curve of 0.901. A combination of fractional anisotropy and maximum relative cerebral blood volume differentiated pseudoprogression from nonpseudoprogression (true progression and mixed) with an area under the curve of 0.807. CONCLUSIONS: DTI and DSC perfusion imaging can improve accuracy in assessing treatment response and may aid in individualized treatment of patients with glioblastomas.