Discussion
Lung cancer is a highly aggressive and deadly disease, accounting for
the highest number of cancer-related deaths worldwide. The main reason
behind this high mortality rate is the asymptomatic nature of lung
cancer during its early stages, leading to late-stage diagnosis when
treatment options are limited.(5)
Various occupational exposures have been identified as potential lung
carcinogens, such as arsenic, asbestos, beryllium, cadmium, chloromethyl
ethers, chromium, nickel, radon, silica, and vinyl chloride. Studies
have estimated that approximately 10% of lung cancer deaths in men and
5% in women globally may be attributed to exposure to these
occupational carcinogens, particularly asbestos, arsenic, beryllium,
cadmium, chromium, nickel, silica, and diesel fumes. In our case, the
patient has a history of working as a mechanic for an extended period of
time, which is considered a potential risk factor for lung cancer. (1)
All patients who are suspected or confirmed to have non-small cell lung
cancer (NSCLC) should have a comprehensive clinical assessment and a
contrast-enhanced CT scan of the chest. If both the clinical evaluation
and CT scan do not reveal any abnormalities outside of the thoracic
region, a PET scan is advised to assess for the presence of metastases.
In cases where the stage of NSCLC is not clearly defined as very early
or advanced, it is recommended to perform lymph node staging within the
thoracic cavity. (5)
Metastasis of lung cancer to axillary lymph nodes is rare. In a 1941
report, Ochsner and DeBakey discussed axillary lymph node metastases for
lung cancer for the first time. They reported a 6.6% incidence of ALNM
in 1,298 lung cancer cases (6). However, Riquet et al. discovered ALNM
in 9 of 1,486 (0.61%) postoperative patients with lung cancer (4).
Satoh et al. additionally noted a 0.75% rate of ALNM from lung cancer
(10 of 1,340 patients). (3)
typically, lymphatic drainage to the ALN comes from the upper limbs and
chest wall instead of the lungs. There have been many theories
hypothesized to explain the unusual pattern of ALN metastases from lung
cancer. The first hypothesis proposed was that ALNM arises through newly
created lymphatic channels developing in the chest wall or a pleural
adhesion (7).
Another possible pathway for ALNM is retrograde spread, which might give
rise to the formation of SCLNM. It has been hypothesized that
involvement of the ipsilateral ALNs in the absence of involvement of the
chest wall requires metastatic diseases to the ipsilateral
mediastinal lymph nodes (MLNs)
and subsequent involvement of the cervical lymph nodes (7–9).
A third pathway of ALNM The involvement of intercostal lymphatics via
dissemination from MLNM is the third suggested mechanism for ALNM (6).
The other suggested mechanism is that ALNM develops as a result of a
systemic disorder.
This was possibly the mechanism in our case, wherein the ipsilateral
axillary lymph node metastasis probably resulted from the ipsilateral
mediastinal lymph nodes (MLNs) and subsequent involvement of the
cervical lymph nodes.
According to TNM staging systems, non-regional lymph node dissemination,
such as ALNM, is categorized as a type of distant metastasis. Patients
with non-regional metastases have a poor prognosis, with survival times
varying from 1 to 10 months (3,4).
In recent years, various therapeutic approaches have been attempted to
combat lung cancer, but they face significant challenges. However, novel
cancer immunotherapy and alternative therapeutic options show promising
potential in improving patient outcomes. Chemotherapy with
platinum-based regimens is the standard treatment for patients with
stage IV non-small cell lung cancer (NSCLC). However, recent
advancements have led to the development of targeted therapies for
specific driver mutations in NSCLC. Additionally, testing for programmed
death ligand-1 expression levels can help guide treatment decisions
involving immunotherapies. While a medical oncologist will oversee the
management of these therapies, it is beneficial for referring clinicians
to be knowledgeable about the available options. (5)
Early detection methods have the potential to significantly impact the
outcomes of lung cancer. This can be achieved through the implementation
of screening programs, increased awareness and recognition of lung
cancer symptoms, and the establishment of clear referral pathways. The
use of low dose CT scanning for lung cancer screening is currently being
evaluated by the UK National Screening Committee. Studies have
demonstrated that this approach is effective in detecting early-stage
lung cancers and has shown improved mortality rates compared to
traditional chest X-ray screenings. (10)