Principal Director, Medical Oncology & Hemato-Oncology, Fortis Hospital, Bannerghatta Road, Bengaluru, India
Part 4 of 12 in Diagnosing Common Cancers & Blood Disorders
When a Persistent Cough Isn't Tuberculosis: Diagnosing Lung Cancer
August 28, 2026
A 52-year-old farmer presented with a persistent cough of two months' duration, accompanied by weight loss, intermittent low-grade fever, and a couple of episodes of coughing up blood. He had no chest pain and no breathlessness. In a region where tuberculosis is common, this presentation reasonably points first toward TB, and that is exactly the path his care took, initially.
A negative GeneXpert did not stop empirical treatment
A chest X-ray showed an inhomogeneous opacity in the upper lobe of the left lung. A GeneXpert test for tuberculosis, which detects acid-fast bacilli, came back negative. Despite the negative result, the patient was started on a four-drug anti-tubercular regimen with pyridoxine, the standard approach when clinical suspicion for TB remains high, weight loss, haemoptysis and fever, even after a negative rapid test.
After two months of anti-tubercular therapy, his symptoms had not improved. He was still coughing and still had haemoptysis. He was referred to Dr. Raizada's team, where a more detailed history revealed a 25-year smoking history at roughly 20 cigarettes a day, a detail that had not been fully weighted in the initial workup.
What the CT and repeat TB testing showed
A CT of the thorax showed a spiculated mass in the left upper lobe measuring 3.5 centimetres, with no pleural effusion. The lesion sat close to the left main pulmonary artery, a detail that could plausibly explain the haemoptysis independent of any TB diagnosis. At this point, every relevant TB test was repeated and remained negative: sputum smear, GeneXpert for acid-fast bacilli, and TB culture, sent both initially and again.
A PET-CT, which combines anatomical imaging from the CT component with functional, metabolic imaging from the PET component, showed the primary lesion in the left upper lobe along with metabolically active mediastinal lymph nodes on both sides.
Choosing the biopsy site: central versus peripheral
Dr. Raizada's rule for any suspicious lung lesion, regardless of whether the differential is TB or malignancy, is that the priority is obtaining adequate tissue from the most accessible site. A lesion close to the bronchus favours bronchoscopy with a bronchoscopic-guided biopsy. A lesion close to the chest wall favours a CT-guided biopsy. In this case, because the lesion sat close to the mediastinum, the team used endobronchial ultrasound, EBUS, to visualise the mediastinal lymph nodes and obtain a needle sample by FNAC or transbronchial needle aspiration, while simultaneously performing a CT-guided biopsy of the primary lesion in the upper lobe. Both procedures mattered here because accurate staging required tissue from both sites.
The biopsy confirmed lung cancer, and because the mediastinal node biopsy was also positive, the disease was staged as T2N2.
Molecular testing is not optional
For patients of South Asian ethnicity specifically, Dr. Raizada was emphatic that molecular testing must be offered: 50 to 60 percent of such patients may express a targetable molecular marker such as EGFR, ALK or ROS1. If positive, targeted oral therapy replaces the need for chemotherapy. Molecular testing is mandatory for all adenocarcinomas and is also recommended for squamous cell carcinoma. Where a repeat tissue biopsy is difficult, a liquid biopsy, a blood test that analyses circulating tumour DNA, can identify the same markers, including EGFR and ALK, and guide the choice of targeted therapy. This patient's treatment plan was chemoradiation.
The red flags, and the screening guideline
The combination that should raise suspicion of malignancy over tuberculosis, even before biopsy results return, is a spiculated mass on imaging, persistent symptoms, no response to a full course of anti-tubercular therapy, and high metabolic activity on PET scan. Any one of these alone is not diagnostic, but together they are a strong indication to pursue tissue diagnosis rather than extend empirical TB treatment further.
On screening, Dr. Raizada noted that regional guidelines are generally extrapolated from the US Preventive Services Task Force recommendation: patients with a 20 pack-year smoking history who have smoked within the past 15 years should receive an annual low-dose CT of the chest between ages 50 and 80, specifically to catch lung lesions requiring evaluation before symptoms like this patient's ever develop.
This guide is based on a live Jivo Masterclass — Dr. Niti Raizada taught doctors across Africa on February 1, 2026.
FROM THE LIVE Q&A
Dr. Innocent Nzili
I am seeing a Stage III breast cancer patient currently on filgrastim 300 micrograms for 3 days. What further treatment plan would you initiate for this patient?
Dr. Niti Raizada
Treatment depends on the patient's oestrogen receptor, progesterone receptor and HER2 status, and on whether she is receiving neoadjuvant chemotherapy followed by surgery, or surgery followed by adjuvant chemotherapy. Filgrastim is supportive care only, a white blood cell growth factor given to prevent a drop in counts after chemotherapy; it is not the primary cancer treatment. Its use depends on which chemotherapy protocol is being followed, but the treatment plan for the cancer itself is a separate, biology-driven decision.
Frequently Asked Questions
Can the HPV vaccine still be given to a patient who has already tested positive for HPV?▼
Yes. If a nine-valent vaccine is given and the patient is positive for one strain of HPV, the vaccine still confers protection against the remaining eight strains it covers.
Are there any specific concerns in monitoring chronic liver disease, for example the frequency of ultrasound and the skill set of the radiographer?▼
Ultrasound should be done once every 6 months for a chronic liver disease patient, along with alpha-fetoprotein testing every 6 months. The skill of the radiographer matters because ultrasound is a subjective, operator-dependent test. If there is any doubt on ultrasound, a triple-phase CT scan or a multiphasic MRI should be done immediately.
We had a case where a gentleman with no history of alcohol or hepatitis could not get preliminary triple-phase CT staging done. The plan was hepatectomy, but he developed a crisis from bile build-up and passed away during the consultation and visa process. How could such cases be managed by a local doctor with limited information?▼
The key is always the right diagnosis at the right time. Liver cancer carries a real risk of coagulopathy and bleeding, so any patient with chronic liver disease should have regular PT, PTT and INR testing. If there is any bleeding diathesis, it needs to be treated, including with vitamin K and blood products if needed. Chronic liver disease patients also commonly have low white cell counts and low platelets, so basic blood counts should be checked regularly alongside liver and kidney function tests.
Could you recap the management of leukemia, including the case you discussed earlier?▼
Leukemias are broadly acute or chronic. Acute leukemias have a short history with low hemoglobin, white cell count and platelets, presenting with fever and bleeding. Chronic leukemias, chronic myeloid leukemia (CML) or chronic lymphocytic leukemia (CLL), generally occur in older age groups and are often managed with tablets alone. Acute leukemias are either AML or ALL. Genetic testing subcategorises each: CML needs confirmation of Philadelphia chromosome or BCR-ABL positivity; CLL needs a FISH panel to check p53 status and risk category; AML is categorised as good, intermediate or high risk. ALL is the most common leukemia in children and young adults and is treated with steroids followed by chemotherapy based on T-cell or B-cell type. AML M3, acute promyelocytic leukemia, is rare but very curable with ATRA or arsenic trioxide tablets; non-M3 AML needs chemotherapy.
What comfort or guidance can you give the doctor partners here, who may not always have clarity because of diagnostic challenges? When should a case trigger further action?▼
Please write in with any questions, over WhatsApp or text, at any time. Many patients cannot travel to India, so the goal is to help diagnose and treat them on time wherever they are. Prepare a doctor's note with the relevant clinical details and share it; if the picture is clear, specific pointers on managing the case can be given from that.
Why might a patient need further workup for cancer even after a negative tuberculosis test?▼
A negative GeneXpert result does not rule out tuberculosis on its own, so empirical anti-tubercular therapy is still reasonable when weight loss, haemoptysis, and fever are present. But if symptoms fail to improve after a full course of treatment and repeated TB tests, including sputum smear, GeneXpert, and culture, remain negative, that lack of response is itself a signal to investigate for malignancy.
How is the biopsy site chosen for a suspicious lung lesion?▼
The choice depends on location. A lesion close to the bronchus favours bronchoscopy with a bronchoscopic-guided biopsy, while a lesion near the chest wall favours a CT-guided biopsy. For a lesion close to the mediastinum, endobronchial ultrasound can visualise lymph nodes for a needle sample while a CT-guided biopsy is taken from the primary lesion at the same time.
Why is molecular testing considered mandatory for certain lung cancer patients?▼
In South Asian patients specifically, 50 to 60 percent may express a targetable marker such as EGFR, ALK, or ROS1. When present, targeted oral therapy can replace chemotherapy, which is why molecular testing is mandatory for all adenocarcinomas and recommended for squamous cell carcinoma as well.
What is a liquid biopsy and when is it used?▼
A liquid biopsy is a blood test that analyses circulating tumour DNA to detect markers such as EGFR and ALK. It is useful when a repeat tissue biopsy is difficult to obtain, allowing clinicians to still identify a targetable mutation and select the appropriate therapy.
Who qualifies for annual lung cancer screening with low-dose CT?▼
Patients with a 20 pack-year smoking history who have smoked within the past 15 years should receive an annual low-dose CT of the chest between ages 50 and 80, a recommendation extrapolated from US Preventive Services Task Force guidance, to catch lung lesions before symptoms develop.
In This Series: Diagnosing Common Cancers & Blood Disorders
- 1.Diagnosing Common Cancers and Blood Disorders
- 2.Breast Cancer in Young Women: Reading the Red Flags Beyond Age
- 3.Breast Cancer Screening: What to Do at 18, 30 and 40
- 4.When a Persistent Cough Isn't Tuberculosis: Diagnosing Lung Cancer
- 5.Colon Cancer, Lynch Syndrome and the Case for Cascade Testing
- 6.Ovarian Cancer: The Silent Killer and Its Diagnostic Trail
- 7.Cervical Cancer: From Diagnosis to Concurrent Chemoradiation
- 8.HPV Vaccination: Who Needs It and What It Prevents
- 9.Hepatocellular Carcinoma: Diagnosing Liver Cancer in Chronic Liver Disease
- 10.Oral Cancer: Recognizing a Non-Healing Ulcer Early
- 11.Acute Promyelocytic Leukaemia: A Bleeding Emergency Hiding in Plain Sight
- 12.The Basic Blood Panel: A GP's First Line of Defence Against Missed Cancers