Illustration combining an x-ray of pectus excavatum with abstract, glowing lungs and swirling energy symbolizing radiation therapy.

Pectus Excavatum & Lung Health: Is There a Hidden Risk?

Rhea Morgan in Health & Wellness December 2025 • 5 min read.

"New research explores whether this chest wall condition influences lung complications after breast cancer radiation therapy."

For women diagnosed with early-stage breast cancer, radiation therapy (RT) following breast-conserving surgery is a common and effective treatment. It reduces the chances of the cancer returning and improves overall survival rates. In Japan alone, approximately 39,800 individuals receive this treatment annually, making the breast the most frequently irradiated primary site.

A standard approach involves three-dimensional conformal radiation therapy (3D-CRT), which uses two tangential beams to target residual breast tissue. While effective in treating the cancer, this method can also expose the lungs to radiation. This raises concerns about potential pulmonary complications, especially for individuals with a chest wall condition called pectus excavatum (PE).

Pectus excavatum, characterized by a sunken or caved-in chest, may cause a larger volume of the lungs to fall within the radiation field during treatment. To investigate this further, a study was conducted to determine if there's a correlation between PE and radiation-induced lung disease (RILD) in breast cancer patients undergoing RT after breast-conserving surgery. The study aims to clarify whether PE increases the risk of lung complications in these patients.

Decoding the Study: Pectus Excavatum, Radiation, and Your Lungs

Illustration combining an x-ray of pectus excavatum with abstract, glowing lungs and swirling energy symbolizing radiation therapy.

The research, recently published in Thoracic Cancer (2018), involved a group of 133 women who underwent 3D-CRT to treat residual breast tissue after breast-conserving surgery for breast cancer. Researchers diagnosed pectus excavatum using established indices like Haller's, frontosagittal, and Monden's. They then meticulously measured radiation doses to the ipsilateral lung (the lung on the same side as the treated breast) using dose-volume histograms.

After carefully evaluating CT scans, 50 of the 133 participants (37.6%) were diagnosed with radiation-induced lung disease (RILD), although all cases were asymptomatic. The analysis uncovered some unexpected relationships between pectus excavatum and lung health after radiation therapy:

V30 Matters: A significant correlation was found between the incidence of RILD and receiving a radiation dose greater than 30 Gy (V30) to the ipsilateral lung.
PE Isn't a Risk Factor: Surprisingly, even though patients with PE received higher doses of radiation to the ipsilateral lung, they were less likely to develop RILD compared to those without PE.
Index Correlations: Further analysis showed relationships between chest wall depression indices and radiation doses to the lung. For example, higher Haller index (HI) and lower frontosagittal index (FSI) – indicative of PE – were strongly correlated with higher doses to the ipsilateral lung.

In short, the study indicated that while the amount of radiation received by the lung is linked to RILD, pectus excavatum itself doesn't seem to increase the risk. In fact, the data suggested those with PE might even have a lower chance of developing RILD, despite receiving higher lung doses.

Key Takeaways: What This Means for You

This study offers reassuring insights for breast cancer patients with pectus excavatum undergoing radiation therapy. While it's natural to be concerned about potential lung complications, the research suggests that PE doesn't increase the risk of RILD. The most important factor remains the radiation dose received by the lung itself.

While the study found that individuals with PE might even have a lower incidence of RILD despite higher lung doses, further research is needed to understand why. Anatomical differences might play a role, and future studies could explore the relationship between the radiation field and central bronchi in patients with PE.

If you have pectus excavatum and are facing radiation therapy for breast cancer, discuss your concerns with your radiation oncologist. This study underscores the importance of carefully planning treatment to minimize radiation exposure to the lungs. In summary, it offers the knowledge that individuals with PE may have a lower incidence of RILD, and further research may reveal a connection.

About this Article -

This article was crafted using a human-AI hybrid and collaborative approach. AI assisted our team with initial drafting, research insights, identifying key questions, and image generation. Our human editors guided topic selection, defined the angle, structured the content, ensured factual accuracy and relevance, refined the tone, and conducted thorough editing to deliver helpful, high-quality information.See our About page for more information.

This article is based on research published under:

DOI-LINK: 10.1111/1759-7714.12933, Alternate LINK

Title: Is Pectus Excavatum A Risk Factor For Radiation-Induced Lung Disease In Patients Undergoing Radiation Therapy Following Breast-Conserving Surgery?

Subject: Pulmonary and Respiratory Medicine

Journal: Thoracic Cancer

Publisher: Wiley

Authors: Naoya Ishibashi, Toshiya Maebayashi, Takuya Aizawa, Masakuni Sakaguchi, Masaharu Hata, Kenichi Sakurai, Masahiro Okada

Published: 2018-12-18

Everything You Need To Know

What is pectus excavatum, and how might it relate to lung health in breast cancer patients receiving radiation therapy?

Pectus excavatum is a chest wall condition characterized by a sunken or caved-in appearance of the chest. In the context of breast cancer treatment, it was thought that pectus excavatum might cause a larger volume of the lungs to fall within the radiation field during radiation therapy, potentially increasing the risk of lung complications. However, research suggests that pectus excavatum itself doesn't seem to increase the risk of radiation-induced lung disease.

What is three-dimensional conformal radiation therapy (3D-CRT), and why is it relevant in the context of pectus excavatum and potential lung complications?

Three-dimensional conformal radiation therapy (3D-CRT) is a standard radiation therapy technique used after breast-conserving surgery for early-stage breast cancer. It involves using two tangential beams to target residual breast tissue. While effective at treating cancer, this method can expose the lungs to radiation, potentially leading to pulmonary complications such as radiation-induced lung disease. The study examined if pectus excavatum influenced the risk of these complications in patients undergoing 3D-CRT.

What is radiation-induced lung disease (RILD), and how was it studied in relation to pectus excavatum and radiation therapy for breast cancer?

Radiation-induced lung disease (RILD) is a potential pulmonary complication of radiation therapy (RT), particularly when the lungs are exposed to radiation during treatment for conditions like breast cancer. In this study, RILD was diagnosed via CT scans, though all cases were asymptomatic. The research aimed to determine if pectus excavatum, a chest wall condition, influenced the occurrence of RILD in breast cancer patients undergoing RT. Interestingly, while a higher radiation dose to the lungs (V30) was linked to RILD, pectus excavatum surprisingly didn't increase the risk.

What are the Haller index (HI) and frontosagittal index (FSI), and how were they used in this study to assess pectus excavatum?

The Haller index (HI) and frontosagittal index (FSI) are established indices used to diagnose and assess the severity of pectus excavatum. A higher Haller index and a lower frontosagittal index are indicative of pectus excavatum. The research found correlations between these indices and the radiation doses received by the ipsilateral lung during breast cancer treatment. For example, higher Haller index and lower frontosagittal index were strongly correlated with higher doses to the ipsilateral lung.

What were the key findings of the study regarding the relationship between pectus excavatum, radiation dose to the lung, and the risk of radiation-induced lung disease (RILD)?

The study revealed that while a higher radiation dose to the ipsilateral lung (V30) is associated with radiation-induced lung disease, pectus excavatum itself did not increase the risk. This suggests that the volume of radiation received by the lung is a more critical factor than the presence of pectus excavatum. This is reassuring for breast cancer patients with pectus excavatum undergoing radiation therapy as they might even have a lower chance of developing radiation-induced lung disease, despite potentially receiving higher lung doses. However, further studies might explore other contributing factors or long-term effects not captured in the research.