Michael I. Ebright

Clinical pattern and pathologic stage but not histologic features predict outcome for bronchioloalveolar carcinoma

BACKGROUND The histologic criteria defining bronchioloalveolar carcinoma (BAC) were recently revised, but it is unclear whether these criteria predict clinical behavior. This study determined the outcome of resected BAC in relationship to clinical and radiologic disease pattern, and pathologic features. METHODS Between 1989 and 2000, 100 consecutive surgically treated patients with adenocarcinomas exhibiting various degrees of BAC features were retrospectively studied. Histology was reviewed; tumors were classified as pure BAC, BAC with focal invasion, and adenocarcinoma with BAC features. Clinical and radiologic pattern were classified as unifocal, multifocal, or pneumonic. Demographic data, tumor stage, and outcome were recorded. Survival was analyzed by the Kaplan-Meier method, and prognostic factors were determined by the log-rank test. RESULTS Patient median age was 65, and 74% of the patients were female. Pure BAC, BAC with focal invasion, and adenocarcinoma with BAC features occurred in 47, 21, and 32 patients, respectively. Unifocal disease occurred in 64 patients, multifocal in 29, and pneumonic in 7. Seventy-one patients had stage I/II tumors, 22 had stage III/IV, and 7 patients had Stage X tumors. Overall 5-year survival was 74%. There was no significant difference in survival among the three histologic subtypes. The pneumonic pattern had significantly worse survival compared with unifocal and multifocal patterns. Pathologic stage predicted survival, with 5-year survivals for I/II and III/IV of 83.7% and 59.6%, respectively. CONCLUSIONS Clinical pattern and pathologic stage, but not the degree of invasion on histologic examination predict survival. Multifocal disease is associated with excellent long-term survival after resection. The favorable survival of stage III/IV BAC indicates that the current staging system does not fully describe this disease in patients undergoing resection because of its distinct tumor behavior.

Neoadjuvant treatment of hepatic malignancy: an oncolytic herpes simplex virus expressing IL-12 effectively treats the parent tumor and protects against recurrence-after resection.

The objective of the study was to evaluate the utility of NV1042, a replication competent, oncolytic herpes simplex virus (HSV) containing the interleukin-12 (IL-12) gene, as primary treatment for hepatic tumors and to further assess its ability to reduce tumor recurrence following resection. Resection is the most effective therapy for hepatic malignancies, but is not possible in the majority of the patients. Furthermore, recurrence is common after resection, most often in the remnant liver and likely because of microscopic residual disease in the setting of postoperative host cellular immune dysfunction. We hypothesize that, unlike other gene transfer approaches, direct injection of liver tumors with replication competent, oncolytic HSV expressing IL-12 will not only provide effective control of the parent tumor, but will also elicit an immune response directed at residual tumor cells, thus decreasing the risk of cancer recurrence after resection. Solitary Morris hepatomas, established in Buffalo rat livers, were injected directly with 107 particles of NV1042, NV1023, an oncolytic HSV identical to NV1042 but without the IL-12 gene, or with saline. Following tumor injection, the parent tumors were resected and measured and the animals were challenged with an intraportal injection of 105 tumor cells, recreating the clinical scenario of residual microscopic cancer. In vitro cytotoxicity against Morris hepatoma cells was similar for both viruses at a multiplicity of infection of 1 (MOI, ratio of viral particles to target cells), with >90% tumor cell kill by day 6. NV1042 induced high-level expression of IL-12 in vitro, peaking after 4 days in culture. Furthermore, a single intratumoral injection of NV1042, but not NV1023, induced marked IL-12 and interferon-γ (IFN-γ) expression. Both viruses induced a significant local immune response as evidenced by an increase in the number of intratumoral CD4(+) and CD8(+) lymphocytes, although the peak of CD8(+) infiltration was later with NV1042 compared with NV1023. NV1042 and NV1023 reduced parent tumor volume by 74% (P<.003) and 52% (P<.03), respectively, compared to control animals. Treatment of established tumors with NV1042, but not with NV1023, significantly reduced the number of hepatic tumors after resection of the parent tumor and rechallenge (16.8±11 (median=4) vs. 65.9±15 (median=66) in control animals, P<.025). In conclusion, oncolytic HSV therapy combined with local immune stimulation with IL-12 offers effective control of parent hepatic tumors and also protects against microscopic residual disease after resection. The ease of use of this combined modality approach, which appears to be superior to either approach alone, suggests that it may have clinical relevance, both as primary treatment for patients with unresectable tumors and also as a neoadjuvant strategy for reducing recurrence after resection.

Treatment of cholangiocarcinoma with oncolytic herpes simplex virus combined with external beam radiation therapy

Replication-competent oncolytic herpes simplex viruses (HSV), modified by deletion of certain viral growth genes, can selectively target malignant cells. The viral growth gene γ134.5 has significant homology to GADD34 (growth arrest and DNA damage protein 34), which promotes cell cycle arrest and DNA repair in response to stressors such as radiation (XRT). By upregulating GADD34, XRT may result in greater oncolytic activity of HSV strains deficient in the γ134.5 gene. The human cholangiocarcinoma cell lines KMBC, SK-ChA-1 and YoMi were treated with NV1023, an oncolytic HSV lacking one copy of γ134.5. Viral proliferation assays were performed at a multiplicity of infection (MOI, number of viral particles per tumor cell) equal to 1, either alone or after XRT at 250 or 500 cGy. Viral replication was assessed by plaque assay. In vitro cytotoxicity assays were performed using virus at MOIs of 0.01 and 0.1, with or without XRT at 250 cGy and cell survival determined with lactate dehydrogenase assay. Established flank tumors in athymic mice were treated with a single intratumoral injection of virus (103 or 104 plaque forming units), either alone or after a single dose of XRT at 500 cGy, and tumor volumes measured. RT-PCR was used to measure GADD34 mRNA levels in all cell lines after a single dose of XRT at 250 or 500 cGy. NV1023 was tumoricidal in all three cell lines, but sensitivity to the virus varied. XRT enhanced viral replication in vitro in all cell lines. Combination treatment with low-dose XRT and virus was highly tumoricidal, both in vitro and in vivo. The greatest tumor volume reduction with combination therapy was seen with YoMi cells, the only cell line with increased GADD34 expression after XRT and the only cell line in which a synergistic treatment effect was suggested. In KMBC and SK-ChA-1 cells, neither of which showed increased GADD34 expression after XRT, tumor volume reduction was less pronounced and there was no suggestion of a synergistic effect in either case. Oncolytic HSV are effective in treating human cholangiocarcinoma cell lines, although sensitivity to virus varies. XRT-enhanced viral replication occurs through a mechanism that is not necessarily dependent on GADD34 upregulation. However, XRT-induced upregulation of GADD34 further promotes tumoricidal activity in viral strains deficient in the γ134.5 gene, resulting in treatment synergy; this effect is cell type dependent. Combined XRT and oncolytic viral therapy is a potentially important treatment strategy that may enhance the therapeutic ratios of both individual therapies.

Detection of Impaired Homologous Recombination Repair in NSCLC Cells and Tissues

Introduction: Homologous recombination repair (HRR) is a critical pathway for the repair of DNA damage caused by cisplatin or poly-ADP ribose polymerase (PARP) inhibitors. HRR may be impaired by multiple mechanisms in cancer, which complicates assessing the functional HRR status in cells. Here, we monitored the ability of non–small-cell lung cancer (NSCLC) cells to form subnuclear foci of DNA repair proteins as a surrogate of HRR proficiency. Methods: We assessed clonogenic survival of 16 NSCLC cell lines in response to cisplatin, mitomycin C (MMC), and the PARP inhibitor olaparib. Thirteen tumor explants from patients with NSCLC were subjected to cisplatin ex vivo. Cells were assayed for foci of repair-associated proteins such as BRCA1, FANCD2, RAD51, and &ggr;-H2AX. Results: Four cell lines (25%) showed an impaired RAD51 foci-forming ability in response to cisplatin. Impaired foci formation correlated with cellular sensitivity to cisplatin, MMC and olaparib. Foci responses complemented or superseded genomic information suggesting alterations in the ATM/ATR and FA/BRCA pathways. Because baseline foci in untreated cells did not predict drug sensitivity, we adapted an ex vivo biomarker assay to monitor damage-induced RAD51 foci in NSCLC explants from patients. Ex vivo cisplatin treatment of explants identified two tumors (15%) exhibiting compromised RAD51 foci induction. Conclusions: A fraction of NSCLC harbors HRR defects that may sensitize the affected tumors to DNA-damaging agents including PARP inhibitors. We propose that foci-based functional biomarker assays represent a powerful tool for prospective determination of treatment sensitivity, but will require ex vivo techniques for induction of DNA damage to unmask the underlying HRR defect.

Electromagnetic Navigation to Aid Radiofrequency Ablation and Biopsy of Lung Tumors

PURPOSE We evaluated an electromagnetic (EM) navigation system (Veran Medical Technologies Inc, St. Louis, MO) to determine its potential to reduce the number of skin punctures and instrument adjustments during computed tomographic-guided percutaneous ablation and biopsy of lung nodules. DESCRIPTION Ten patients undergoing lung percutaneous ablation were prospectively enrolled. The mean age was 70 years. Positioning of the needle device was verified with computed tomographic fluoroscopy prior to the execution of any biopsy or ablation. Each EM navigation-guided procedure was defined as an EM-intervention. EVALUATION Nineteen EM interventions were performed. When an EM-guided biopsy was performed, the intervention was done immediately prior to ablation. For all 19 EM interventions, only one skin-puncture was required. The mean number of instrument adjustments required was 1.2 (range, 0 to 2). The mean time for each EM intervention was 5.2 minutes (range, 1 to 20 minutes). Pneumothorax occurred in 5 patients (50%). Only the number of instrument adjustments was significantly related to the pneumothorax rate (p = 0.005). CONCLUSIONS The EM navigation is feasible and seems to be a useful aid for image-guided procedures. Early experience suggests a low number of skin-puncture and instrument adjustments using the EM navigation system. Instrument adjustments were a key factor in pneumothorax development.

Positron emission tomography combined with diagnostic chest computed tomography enhances detection of regional recurrence after stereotactic body radiation therapy for early stage non–small cell lung cancer

OBJECTIVE(S) Recommendations for surveillance after stereotactic body radiation therapy (SBRT) for early stage non-small cell lung cancer (NSCLC) are not well defined. Prospective studies evaluating the efficacy of SBRT have used interval posttreatment imaging with computed tomography (CT). We set out to determine whether positron emission tomography (PET) combined with diagnostic chest CT (PET/d-chest) can enhance detection of potentially salvageable recurrence after SBRT. METHODS We performed a retrospective analysis of posttreatment imaging for 35 patients consecutively treated with SBRT for biopsy-proven early-stage NSCLC. PET/d-chest was generally performed every 3 months after treatment. A board-certified radiologist who did not have access to the PET results retrospectively interpreted the CT scans. CT results were reported according to response criteria used in Radiation Therapy Oncology Group 0236 and compared with PET/d-chest readings. Local and regional recurrence-free survival was compared using the Mantle-Cox (log-rank) test. RESULTS Median follow-up was 12.8 months. Twenty-four patients had stage IA, 7 stage IB, 3 stage IIA, and 1 stage IIB biopsy-proven NSCLC. Two-year overall survival was 62%. CT scans indicated no regional recurrences. PET/d-chest indicated 10 regional recurrences. The 1-year rate of regional recurrence-free survival as evaluated by CT and PET/d-chest was 100% and 69.4%, respectively (P = .0045). Four of 10 patients with a diagnosis of regional recurrence underwent salvage treatment with definitive chemoradiotherapy. CONCLUSIONS PET/d-chest enhances the detection of regional progression of NSCLC after SBRT over currently recommended practices. In patients who are fit for salvage treatment, where early detection of recurrence can increase the likelihood of successful treatment, PET/d-chest appears critical for follow-up.

Radiofrequency ablation for Barrett's esophagus and low-grade dysplasia in combination with an antireflux procedure: a new paradigm.

OBJECTIVE Radiofrequency ablation for Barretts esophagus in combination with an antireflux procedure has not been widely documented. We report our initial experience with radiofrequency ablation in association with antireflux procedure for Barretts metaplasia and low-grade dysplasia. METHODS A total of 14 patients (10 male and 4 female patients) presented with Barretts metaplasia (n=11) or low-grade dysplasia (n=3). Median age was 60 years (38-80 years). The severity of Barretts esophagus was classified by length (in centimeters), appearance (circumferential/noncircumferential), and histology (1, normal; 2, Barretts metaplasia; and 3, low-grade dysplasia). Radiofrequency ablation was performed with the HALO 360 degrees or 90 degrees systems (BARRX Medical, Sunnyvale, Calif). RESULTS Median follow-up was 17 months. The mean number of ablative procedures undertaken was 2.6 (range, 1-6). There was no mortality, but there were 2 perioperative complications after the antireflux procedure (pneumonia, 1; atrial fibrillation, 1). One patient had mild dysphagia requiring a single dilation 2 months after ablation. The mean length of Barretts esophagus decreased from 6.2 to 1.2 cm after treatment (P=.001). Barretts grade decreased significantly (P=.003). Before therapy, circumferential Barretts esophagus was present in 13 patients. At last endoscopy, only 1 patient had circumferential Barretts esophagus present. The number of radiofrequency ablation treatments was significantly (P < .05) associated with success. All patients receiving 3 or more treatments had complete resolution of Barretts metaplasia. CONCLUSIONS Radiofrequency ablation performed either before or after an antireflux procedure is safe. This approach is effective for reducing or eliminating metaplasia and dysplasia. Long-term studies will be necessary to determine whether this approach can provide durable control of both reflux and Barretts esophagus.

Effect of murine liver cell proliferation on herpes viral behavior: Implications for oncolytic viral therapy

Replication‐competent herpes simplex oncolytic viruses are promising anticancer agents that partly target increased DNA synthesis in tumor cells. Investigators have proposed that these DNA viruses may be combined with liver resection to enhance killing of liver malignancies. Whether or not the cellular alterations associated with hepatic regeneration affect the efficacy and toxicity of these promising anticancer agents is unknown. This study examined the behavior of two oncolytic viruses, NV1020 and G207, during liver regeneration. When delivered during the peak of liver regeneration, replication and appearance of both G207 and NV1020 in hepatic tissue are enhanced as demonstrated by histochemical staining for the marker gene lac Z, immunohistochemical staining, and quantitative polymerase chain reaction. This increased appearance of virus in liver tissue correlates with increases in cellular ribonucleotide reductase activity and DNA synthesis and is also associated with increased viral binding. However, increased viral presence is transient, and viral detection declines to baseline within 7 days. When these viruses were delivered to animals even as early as 7 days after hepatectomy, there proved to be no measurable viral replication in any organ and no increased morbidity or mortality. In conclusion, the early stages of hepatic regeneration after resection provide an environment suitable for viral replication. Administration of replication‐competent herpes simplex virus during the peak of hepatocyte regeneration (24–48 hours) permits viral productivity in tissue that otherwise does not support viral growth. The increase in hepatotoxicity after hepatectomy is short‐lived and can be predicted by peak hepatocyte DNA synthesis. (HEPATOLOGY 2004;39:1525–1532.)

Electromagnetic navigational bronchoscopy with dye marking for identification of small peripheral lung nodules during minimally invasive surgical resection

BACKGROUND Identification of small peripheral lung nodules during minimally invasive resection can be challenging. Electromagnetic navigational bronchoscopy (ENB) with injection of dye to identify nodules can be performed by the surgeon immediately prior to resection. We evaluated the effectiveness of ENB with dye marking to aid minimally invasive resection. METHODS Patients with peripheral pulmonary nodules underwent ENB before planned thoracoscopic or robotic-assisted thoracoscopic resection. Methylene blue was injected directly into the lesion for pleural-based lesions or peripherally for lesions deep to the pleural surface. Surgical resection was then immediately performed. Technical success was defined as identification of the dye marking within/close to the lesion with pathological confirmation after minimally invasive surgical resection. RESULTS Seventeen patients (19 nodules) underwent ENB with dye marking followed by minimally invasive resection. Median lesion size was 9 mm (4-32 mm) and the median distance from the pleura was 9.5 mm (1-40 mm). Overall success rate was 79% (15/19). In two cases the dye was not visualized and in the remaining two there was extravasation of dye into the pleural space. There were trends favoring technical success for nodules that were larger or closer to the pleural surface. Five patients required adhesiolysis to visualize the target lesion and all were successful. There were no significant adverse events and a definitive diagnosis was ultimately accomplished in all patients. CONCLUSIONS ENB with dye marking is useful for guiding minimally invasive resection of small peripheral lung nodules. ENB can be undertaken immediately before performing resection in the operating room. This improves workflow and avoids the need for a separate localization procedure.

Surgical Resection or Stereotactic Body Radiation Therapy in Elderly Patients With Early-Stage Lung Cancer: Evolving Treatment Algorithms and a Call for Reliable Comparisons

David Palma and colleagues report on the impact of stereotactic body radiation therapy (SBRT) on treatment patterns of elderly patients in the Netherlands. This study, published recently in the Journal of Clinical Oncology, is a retrospective review of data collected by the Amsterdam Cancer Registry. This study highlights many of the difficulties encountered when comparing the effectiveness of surgical resection and SBRT.