From the Guidelines
The prognosis for stage III lung cancer is generally poor, with a 5-year survival rate ranging from 10% to 30%, but recent advances in targeted therapies and immunotherapies have improved outcomes for some patients. This stage represents locally advanced disease where cancer has spread to nearby lymph nodes or structures but has not metastasized to distant organs. Treatment typically involves a multimodal approach combining chemotherapy, radiation therapy, and possibly surgery depending on the specific characteristics of the tumor and the patient's overall health. For non-small cell lung cancer (NSCLC), which accounts for about 85% of lung cancers, concurrent chemoradiation followed by immunotherapy (durvalumab) for eligible patients has become a standard approach, potentially improving survival outcomes, as suggested by the 2022 ASCO guideline 1.
Factors that influence prognosis include the patient's performance status, age, specific lung cancer subtype, molecular markers (such as EGFR, ALK, or PD-L1 status), and response to initial treatment. The use of radiotherapy alone as a curative mode of therapy for stage IIIA or IIIB disease yields poor survival at 5 years (5%-10%) with traditional dose and fractionation schedules, as noted in the 2013 American College of Chest Physicians evidence-based clinical practice guidelines 1. However, combining systemic chemotherapy with radiotherapy has shown improved survival rates in multiple phase 3 trials using platinum-based chemotherapy, with acceptable levels of toxicity 1.
While stage III lung cancer is serious, advances in targeted therapies and immunotherapies have improved outcomes for some patients in recent years, making it important to undergo comprehensive biomarker testing to identify potential treatment options. The management of stage III NSCLC is heterogeneous and varies significantly among clinicians, with variations being observed across institutes and within an institute, highlighting the need for evidence-based guidance, as provided by the 2022 ASCO guideline 1. Key considerations in treatment decision-making include performance status, comorbid illnesses, and other medical factors, in addition to the clinical and radiographic characteristics of the cancer.
From the Research
Prognosis for Stage III Lung Cancer
The prognosis for stage III lung cancer varies depending on the treatment approach and patient characteristics.
- The 5-year survival rate for stage III lung cancer patients has been reported to range from 2% to 15% 2, with a median survival time of 0.84 years (10.1 months) 3.
- Treatment outcomes:
- Neoadjuvant chemotherapy followed by resection has been shown to improve survival outcomes, with a 5-year survival rate of 63% compared to 19% for chemoradiation alone 2.
- Sequential chemoradiotherapy has been identified as an independent predictor of the risk of death, with an adjusted hazard ratio of 1.58 3.
- Curative resection has been associated with a 5-year survival rate of 31.8%, increasing to 42% for T3N0M0 patients 4.
- Definitive radiotherapy with or without chemotherapy has resulted in a 5-year overall survival rate of 22.2% and a median survival of 18 months 5.
- Neoadjuvant chemoradiotherapy followed by resection has been shown to improve long-term survival, with a 5-year survival rate of 24% in the whole group and 39% in the surgical cohort 6.
Factors Affecting Survival
Several factors have been identified as affecting survival in stage III lung cancer patients, including:
- Sex: females have been shown to have a lower mortality risk compared to males, with an adjusted hazard ratio of 0.74 3.
- Stage of disease: stage IIIB and III (unknown and undefined) have been associated with a higher risk of death compared to stage IIIA, with adjusted hazard ratios of 1.33 and 1.48, respectively 3.
- Treatment approach: the choice of treatment, including neoadjuvant chemotherapy, resection, and chemoradiation, can significantly impact survival outcomes 2, 4, 5, 6.
- Tumor location: patients with primary tumors located in the superior lobe appear to have a better clinical outcome, with significant differences in survival and fatal radiation pneumonitis rate compared to those with middle or inferior lobe lesions 5.