Lung Cancer
Answering questions about lung cancer is difficult as a general surgery resident because you are spending much of your time studying general surgical diseases. So I have compiled some training for you.
How to Work up a Patient – How I do it
When you are in front of the entire surgery department and asked, “How to you work up a patient with lung cancer?”, the following this general work up is my preferred approach:
You can start by saying “To work up a patient with lung cancer, I break it down into three parts.”:
- Assessment of the Tumor
- Staging of the Tumor
- Assessment of the Patient
Now, here are the steps I follow each time, in a checklist/check the box format.
1. Assessment of the Tumor
[ ] Review Scans:
- CXR, CT Chest
- assess size, resectability, is it the only tumor – liver, adrenals, thyroid, granulomas – these are the most common other findings
[ ] Establish a Diagnosis:
- Modes of biopsy: Bronchoscopy, CT guided biopsy(core needle) is the most common, Navigational bronchoscopy(FNA) is becoming more common.
- Most common types of lung cancer: Adenocarcinoma, Squamous Cell carcinoma, Carcinoid (neuroendocrine)
- It is important to establish a diagnosis, I almost never operate without a ‘specific diagnosis’
2. Staging of the Tumor
[ ] PET/CT: Evaluation for distant metastasis, mediastinal node uptake.
[ ] Endobronchial Ultrasound (EBUS): biopsy of mediastinal nodes. This has taken the place of mediastinoscopy.
- paratracheal 4R/4L, subcarinal 7)
- hint: mediastinal nodes are single digit stations, and hilar nodes are double digit
[ ] MRI Brain – Brain MRI is standard practice as part of staging. Some centers perform brain MRI only in the setting of larger tumors (>3cm), or if patient has neurologic symptoms.
3. Assessment of the Patient
[ ] Complete History and Physical – always say this of course! I will not list all that goes into a thorough H&P. This is an overview of How I Do It
- Find out how was the tumor found – you always need to know this!
- Ask about the following: shortness of breath, cough/hemoptysis, chest pain/shoulder pain, home O2/CPAP
- Four questions I always ask: (1)”did you ever have chest surgery/radiation”, (2)”did you ever smoke”, (3)”did you ever take blood thinner for any reason”, (4)”are you still working and if so what do you do?”
- Assess for any extra-thoracic symptoms of thoracic malignancy: wt loss, flushing, diarrhea, palpitations, fatigue, or basically any paraneoplastic symptom you can think of
- Gather all the medical issues – Cardiac/Pulmonary/Renal/Liver disease, CVA, etc. Don’t ever miss anything that will increase the risk of surgery! Make a list in your mind of conditions that will increase risk: immune suppression, vocal cord paralysis, previous radiation, etc.
- Physical Exam: These are things I watch close for: murmur, afib, radiation tattoo marks (some elderly pt’s forget they had radiation), distant breath sounds – beware of very distant breath sounds – marker of bad lungs!
[ ] Lung Function: PFTs, ABG, Quantitative VQ, Cardiopulmonary exercise testing
- Lobectomy: preop FEV1 >1.5 or >60%, DLCO >60%
- Pneumonectomy: preop FEV1 >2.0 or >80%, DLCO >80%
- Predicted Postop FEV1** (ppoFEV1) >0.8 or 40%, DLCO >40%
- ABG: PCO2 < 60, PaO2>70 on room air
- If marginal lung function start with Quan VQ to see if resected area contributes less than expected
- If still marginal – I go straight to cardiopulmonary exercise testing – VO2<15 high risk for surgery
[ ] Cardiac Evaluation: Similar to any preop surgical evaluation
- Cardiac history – MI, CHF, afib
- ECHO
- Age >70, Risk factors – cardiology evaluation
- As a basic rule: angina, previous MI, CHF, EF<40%, valvular disease, uncontrolled arrhythmias trigger a cardiology evaluation
[ ] Functional Status – less quantitative
- Eye ball test
- Frailty Test: I always ask, how far can you walk? Or, what limits you from walking long distances (bad knees, back, etc). Do you use a scooter at the store?
- How bad do they want to recover and get back to their normal activities. This can be difficult to differentiate in a very anxious or nervous patient and family that really want the surgery be done as soon as possible, rather than a legitimate drive to recover and improve.
[ ] Findings on Imaging: Important findings that help with assessing the patient
- elevated hemidiaphragm, sternal wires, clips in the chest – where in the world did those come from? Better find out!
Now putting all of this together:
I will offer the patient surgery if (1) the tumor is completely resectable, (2) staging is negative, and the (3) patient appears to be an appropriate risk or candidate for surgery from pulmonary, cardiac, medical, and functional standpoint.
Then they will all say, “you are amazing!”, because of course, you are.
**Predicted Post op FEV1 Formulas: This is a little beyond the scope of this training, but here it is:
- PPO FEV1 = preop FEV1 x (number of segments remaining postoperatively/total number of lung segments [normally 18])
- PPO FEV1 = preoperative FEV1 x (1 – number of segments removed/number of total segments) which is typically 19. Analogous formulas for DLCO can be used (PPODLCO).
Surgical Treatment of Lung Cancer
Anatomic Resection: Lobectomy is standard of care. Other options are sublobar or segmental resection for smaller tumors.
Wedge Resection: if the mass is peripheral and patient at increased risk for anatomic resection.