Lung cancer is a biologically diverse disease. Non-small cell lung cancer (NSCLC), which represents about 80% of all lung cancer, is the leading worldwide cause of cancer-related death. NSCLC consists of adenocarcinoma, squamous cell carcinoma and large cell carcinoma (1). There are a number of conventional chemotherapeutic regimens available for NSCLC that, due to the heterogeneity of the disease at pathological, cellular and molecular levels, do not have the same effectiveness in individual patients. Oncologists have to decide which of the conventional regimens would potentially be optimal for a particular patient. The selection is crucial since the currently available chemo drugs are quite toxic and the toxic side effects of an ineffective regimen could preclude use of additional chemotherapy (2). There is therefore a need for reliable and relatively rapid chemosensitivity screening of an individual patient’s NSCLC, aimed at identifying the best regimen for personalized chemotherapy of the patient on the basis of the patient’s tumor biology. Several chemosensitive tests have been developed based on resected NSCLCs from patients, including in vitro tests using short-term cell cultures (3) and in vitro tests using first-generation tissue xenografts in immuno-deficient mice (4). An important criterion for such assays is that the cancer cell cultures and xenografts closely resemble the original cancers, in particular with respect to features that have a role in the chemosensitivity of the malignancy, including tumor heterogeneity and micro-environment (5). While in vitro assays based on short term cultures of patients’ cancer cells are useful, the cell cultures do not possess the tissue architecture of the original specimens and lack interaction of cancer cells with factors from the original environment (e.g., stroma). As well, the transfer of cancer cells from the patient to the highly artificial in vitro environment may lead to loss of cancer subpopulations with different chemosensitivities. As such, the in vitro models generally do not accurately represent the patients’ cancers. More accurate preclinical models are thought to be provided by subrenal capsule xenografts of patients’ cancer tissues in SCID mice, since especially the first-generation xenografts tend to retain the cellular heterogeneity, architectural and molecular characteristics of the original cancer. This appears to be mainly due to the use of cancer tissue preserving the original micro-environment (as distinct from enzyme-digested cells), and use of the renal graft site which offers an abundant supply of nutrients, hormones, growth factors and oxygen to the transplanted tissue (4).