Role of surgery following induction therapy for stage III non-small cell lung cancer

Development of single nanometer-sized ultrafine oxygen bubbles to overcome the hypoxia-induced resistance to radiation therapy via the suppression of hypoxia-inducible factor‑1α

Radiation therapy can result in severe side-effects, including the development of radiation resistance. The aim of this study was to validate the use of oxygen nanobubble water to overcome resistance to radiation in cancer cell lines via the suppression of the hypoxia-inducible factor 1-α (HIF-1α) subunit. Oxygen nanobubble water was created using a newly developed method to produce nanobubbles in the single-nanometer range with the ΣPM-5 device. The size and concentration of the oxygen nanobubbles in the water was examined using a cryo-transmission electron microscope. The nanobubble size was ranged from 2 to 3 nm, and the concentration of the nanobubbles was calculated at 2×10¹⁸ particles/ml. Cell viability and HIF-1α levels were evaluated in EBC-1 lung cancer and MDA-MB-231 breast cancer cells treated with or without the nanobubble water and radiation under normoxic and hypoxic conditions in vitro. The cancer cells grown in oxygen nanobubble-containing media exhibited a clear suppression of hypoxia-induced HIF-1α expression compared to the cells grown in media made with distilled water. Under hypoxic conditions, the EBC-1 and MDA-MB231 cells displayed resistance to radiation compared to the cells cultured under normoxic cells. The use of oxygen nanobubble medium significantly suppressed the hypoxia-induced resistance to radiation compared to the use of normal medium at 2, 6, 10 and 14 Gy doses. Importantly, the use of nanobubble media did not affect the viability and radiation sensitivity of the cancer cell lines, or the non-cancerous cell line, BEAS-2B, under normoxic conditions. This newly created single-nanometer range oxygen nanobubble water, without any additives, may thus prove to be a promising agent which may be used to overcome the hypoxia-induced resistance of cancer cells to radiation via the suppression of HIF-1α.

Outcome of Patients With pN2 "Potentially Resectable" Nonsmall Cell Lung Cancer Who Underwent Surgery After Induction Chemotherapy

Patients with stage IIIA-ipsilateral mediastinal lymph node involvement (N2) non-small cell lung cancer (NSCLC) represent a heterogeneous group with different clinical presentation. The aim of this study was to analyze a series of patients with "potentially resectable" stage IIIA-pathologically proven N2 (pN2) NSCLC undergoing induction chemotherapy followed by surgery to evaluate their long-term outcomes and to identify prognostic factors. Out of 287 patients who underwent induction chemotherapy for NSCLC with ipsilateral mediastinal lymph node involvement pathologically proven, we retrospectively evaluated 141 (49%) patients with no clinical evidence of progression after induction chemotherapy and candidates for surgery. Most of them (73%) underwent at least 3 cycles of cisplatin-based chemotherapy. We used the Kaplan-Meier method to plot survival and the log-rank test to assess the survival difference between groups. Multivariable analysis was performed using Cox proportional hazards regression. A total of 15 (10.6%) patients underwent explorative thoracotomy; 126 patients underwent surgical anatomical resection after a median 27 days (range: 21-30) from the last cycle of chemotherapy. A total of 113 (89.7%) patients had a radical resection. A total of 22 (17.5%) patients had a complete pathologic lymph node downstaging (pN0), and 8 (6.3%) patients had a complete pathological response (pT0N0). The median overall survival was 24 months, with a 5-year overall survival of 30%. At multivariable analysis, downstaging and number of cycles of chemotherapy were independent prognostic factors (P = 0.006); downstaging benefit was mostly because of complete pathological response (hazards ratio = 0.23, 95% CI: 0.07-0.76). In conclusion, more than 3 cycles of chemotherapy and pathological downstaging could significantly improve 5-year survival in selected patients with "potentially resectable" pathologically proven N2 disease.

ACR Appropriateness Criteria(®) induction and adjuvant therapy for N2 non-small-cell lung cancer

The integration of chemotherapy, radiation therapy (RT), and surgery in the management of patients with stage IIIA (N2) non-small-cell lung carcinoma is challenging. The American College of Radiology (ACR) Appropriateness Criteria Lung Cancer Panel was charged to update management recommendations for this clinical scenario. The Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every 3 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances where evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment. There is limited level I evidence to guide patient selection for induction, postoperative RT (PORT), or definitive RT. Literature interpretation is complicated by inconsistent diagnostic procedures for N2 disease, disease heterogeneity, and pooled analysis with other stages. PORT is an appropriate therapy following adjuvant chemotherapy in patients with incidental pN2 disease. In patients with clinical N2 disease who are potential candidates for a lobectomy, both definitive and induction concurrent chemotherapy/RT are appropriate treatments. In N2 patients who require a pneumonectomy, definitive concurrent chemotherapy/RT is most appropriate although induction concurrent chemotherapy/RT may be considered in expert hands. Induction chemotherapy followed by surgery +/- PORT may also be an option in N2 patients. For preoperative RT and PORT, 3-dimensional conformal techniques and intensity-modulated RT are most appropriate.