Lung Cancer

Lung Cancer Facts

According to the American Cancer Society’s Cancer Facts and Figures, lung cancer is currently the second most common cancer diagnosed in both men and women in the United States, as well as the leading cause of cancer related deaths in both sexes, accounting for an estimated 27% of all cancer deaths. It’s estimated that there will be 228,390 new cases of lung cancer diagnosed in the United States this year, with 52% of the cases diagnosed in men, and 48% diagnosed in women. The total number of cases accounts for 14% of all cancer diagnosis made. Of that number, an estimated 5,960 cases will be diagnosed in New Jersey residents.

Histological Types

Lung cancers are classified into two broad categories; small cell carcinoma (SCLC), and non-small cell carcinoma (NSCLC). Small cell carcinomas usually account for 15% of all lung cancers, while non-small cell accounts for 85%. Approximately half of all non-small cell carcinomas are diagnosed at lower, more localized stages, whereas small cell carcinomas are typically diagnosed after the establishment of nodal and distant metastases. Since SCLC and NSCLC behave and are treated differently, microscopic tissue diagnosis to determine the type is essential. Newer chemotherapeutic options depend on this distinction to determine the most effective and appropriate treatment.

New research has discovered that lung cancer cells often harbor mutations and rearrangement of genetic material. Two of these mutations make those cancers particularly susceptible to specific targeted therapeutic agents. Genetic analysis may enable the medical oncologist to provide tailored, personalized treatment for a particular patient with a particular tumor.

Diagnosis Techniques

Tissue diagnostic and pathologic staging has been done via biopsy, and standard bronchoscopy. Ultrasound-guided needle aspiration and navigational bronchoscopy are newer techniques that supplement these traditional approaches.

Due to concern about radiation exposure, computed tomography (CT) scanners capable of excellent crosssectional imaging with low doses of radiation are now available.

Staging

Accurate staging is extremely important in determining the proper treatment options for a patient at the time of initial diagnosis.

The American Joint Committee on Cancer’s TNM staging system has traditionally been used by clinicians for staging patients. A new Lymph Node Map is also used to internationally standardize lymph node nomenclature.

Treatment Options

Treatment options are determined by the type of cancer, small cell versus non-small cell, and the stage of disease at the time of initial diagnosis. Recently, treatment options are becoming further refined according to adenocarcinoma (ADC) versus squamous cell carcinoma (SCC) and according to the mutation status of the individual tumor. Traditionally treatment included surgery, chemotherapy, radiation therapy, or a combination thereof. Each of these modalities has undergone rapid recent evolution with sub-options, as discussed above regarding chemotherapy.

Surgery is typically the treatment of choice for early stage non-small cell lung cancer. By contrast, small cell carcinoma is typically metastatic at the time of initial diagnosis in 80% of newly diagnosed cases, therefore these cases are primarily managed with systemic therapy rather than surgical resection.

The standard of care surgical resection for NSCLC has been lobectomy if appropriate. Sublobar resections are now being considered and investigated for effectiveness in small cancers that may be considered to be less aggressive. Ancillary techniques, such as electromagnetic navigation bronchoscopic pleural dye marker (continued) placement can be used to guide VATS or robotic wedge biopsies or sub-lobar resections. This satisfies the need for minimally invasive, lung-sparing, surgical technique in an environment where CT scans are facilitating discovery of ever smaller lung cancers.

Developments in imageimage-guided and image-modulated radiation therapy have enabled new modalities for radiation delivery with increased precision, target destruction, and sparing of normal tissues. Techniques such as stereotactic ablative radiation treatment, sometimes optimized with the placement of endobronchial radiosurgical markers. PET-CT can be to facilitate radiation planning and enable involved-field radiation therapy.

Cancers which are unresectable at the time of initial diagnosis and staging are treated either with chemotherapy alone or a combination of chemotherapy and radiation.

Survival Analysis

The 1-year relative survival rate for all lung cancers have increased over the past 20 years, largely due to improvements in surgical techniques and combined therapies, however the overall relative 5-year survival rate remains quite low, particularly for patients diagnosed with late stage disease.

Conclusions

While lung cancer incidence and mortality rates have continued to decline in recent years, it still accounts for more deaths than any other cancer in both men and women, and more women continue to die each year from lung cancer than from breast cancer. The decreasing rates are thought to be reflective of decreased smoking over the past 3 decades.

Chest x-rays, sputum analysis, and fiber-optic examination have not shown effectiveness in improving overall survival for lung cancer patients. Newer tests, such as spiral CT and molecular markers in sputum may offer promising opportunities to detect earlier stage lung cancer, resulting in an increased survival rate.

The National Lung Screening Trial (NLST) is a cancer screening trial funded by the National Cancer Institute (NCI) designed to determine if screening high-risk individuals with low dose CT can reduce lung cancer death. Early results have shown 20% fewer disease-specific deaths and 6% fewer all-cause deaths in current and former heavy smokers who were screened using spiral CT as compared with chest x-ray. Different interested agencies have issued statements as to the potential widespread application of NLST-style population screening, but further research, consideration, and regulation is ongoing.

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