Lung cancer
What is lung cancer?
There are three main types of two cancer, depending on which cells have turned cancerous:
- Small-cell lung cancer (SCLC) ~15% of cases
- Non-small-cell lung cancer (NSCLC) ~85% of cases
- Gland-cell cancers (adenocarcinomas) ~40% of cases
- Flat-cell cancers (squamous-cell carcinomas) ~30% of cases
- Large-cell carcinomas ~15% of cases
There are also other, rare types of lung cancer.
What are the symptoms?
Diagnosis
Definitive diagnosis of lung cancer requires a tissue sample (biopsy) of the suspected tumor be examined by a pathologist under a microscope.
How can it be treated?
- Surgery
- Chemotherapy
- Radiation therapy
- Targeted drugs
Clinical studies
For locally advanced or metastatic NSCLC, the US Food and Drug Administration (FDA) considers overall survival (OS), a time-to-event endpoint, the standard clinical benefit endpoint for establishing efficacy. Most of the NSCLC approvals reviewed in its guidance were based on an improvement in OS, because median survival was short, less than a year, so using OS rarely made trials longer than using progression-free survival (PFS) or the objective tumor response rate (ORR) would have. PFS, a tumor-based time-to-event endpoint, may be appropriate as the primary endpoint if the trial is designed to show a large treatment effect. Because tumor assessments are subjective and depend on how often, accurately and completely they are made, the observed effect on PFS should be substantial and statistically robust. Effects on ORR have not been shown to reliably predict effects on survival in NSCLC, and the FDA considers ORR alone reasonably likely to predict clinical benefit only when the effect is large and the responses are durable. Because response to treatment varies across molecular and histological subgroups of NSCLC, the FDA recommends designing trials prospectively to evaluate these differences [1].
Clinical pharmacology studies
The European Medicines Agency (EMA) guideline on anticancer drugs, which covers cancer in general, says that phase 1 dose-finding trials of cell-killing chemotherapy (cytotoxic drugs) should normally be run in cancer patients without established treatment options, while early trials of non-cytotoxic drugs may sometimes be run in healthy volunteers. If a hepatic impairment study is needed and cancer that has spread to the liver (liver metastases) is common in the target population, a study in patients with liver metastases is warranted as a first step. Exploratory studies, including pharmacokinetics, are encouraged in patients with fluid collecting in body spaces (third-space conditions), such as fluid in the abdomen caused by the cancer (malignant ascites) or a large amount of fluid around the lungs, where these occur in the cancer being treated [2].