Respiratory system

TUMOURS OF THE BRONCHUS AND LUNG4th year Medical

The burden of lung cancer
Cigarette smoking is by far the most important cause of lung cancer., for at least 90 being proportional to the amount smoked and to the tar content of cigarettes. The death rate from the disease in heavy smokers is 40 times that in non-smokers. Risk falls slowly after smoking cessation, but remains above that in non-smokers for many years Exposure to naturally occurring radon is another risk. The incidence of lung cancer is slightly higher in urban than in rural dwellers.which may reflect differences in atmospheric .

Bronchial carcinoma

Bronchial carcinomas arise from the bronchial epithelium or mucous glands.With Lymphatic spread &or Blood-borne metastases . The common cell types are: Squamous30-35%, Adenocarcinoma40-30%, Small-cell20%, spread very fast and Large-cell 15%. Tumour occurs in a large bronchus, symptoms arise early, but tumours originating in a peripheral bronchus can grow very large without producing symptoms, resulting in delayed diagnosis. Peripheral squamous tumours may undergo central necrosis and cavitation, and may resemble a lung abscess on X-ray .

Clinical Presentation of Bronchial carcinoma

Cough. Haemoptysis. Occasionally, central tumours invade large vessels, causing sudden massive haemoptysis which may be fatal. Bronchial obstruction.Complete obstruction causes collapse of a lobe or lung, Partial bronchial obstruction may cause a monophonic, unilateral wheeze that fails to clear with cough. Pneumonia that recurs at the same site. Stridor (a harsh inspiratory noise) occurs when the lower trachea,. Breathlessness. This may be caused by collapse or pneumonia, or by tumour causing a large pleural effusion or compressing a phrenic nerve causing diaphragmatic paralysis.

Clinical Presentation of Bronchial carcinoma

Pain and nerve entrapment. Pleural pain usually indicates malignant pleural invasion. Carcinoma in the lung apex may cause Horner's syndrome (ipsilateral partial ptosis, enophthalmos, miosis and hypohidrosis of the face due to involvement of the sympathetic chain at or above the stellate ganglion. Pancoast's syndrome, malignant destruction of the T1 and C8 roots. Mediastinal spread. Involvement of the oesophagus may cause dysphagia. If the pericardium, arrhythmia or pericardial effusion .. Superior vena cava obstruction,left recurrent laryngeal nerve Supraclavicular lymph nodes ,Digital clubbing& Hypertrophic pulmonary osteoarthropathy (HPOA),

Clinical Presentation of Bronchial carcinoma

Non-metastatic extrapulmonary effects .Syndrome of inappropriate antidiuretic hormone secretion (SIADH) and ectopic adrenocorticotrophic hormone secretion are usually associated with small-cell lung cancer Hypercalcaemia is usually caused by squamous cell carcinoma. Associated neurological syndromes may occur with any type of bronchial carcinoma

Non-metastatic extrapulmonary manifestations of bronchial carcinoma

Endocrine Inappropriate antidiuretic hormone secretion causing hyponatraemia Ectopic adrenocorticotrophic hormone secretion Hypercalcaemia due to secretion of parathyroid hormone-related peptides Carcinoid syndrome Gynaecomastia

Non-metastatic extrapulmonary manifestations of bronchial carcinoma

Investigations for Bronchial carcinoma
Plain X-rays CT is usually performed for : localization,operability, metastatic spread and for accessible or not by bronchoscopy . Bronchoscopy ;three-quarters of primary lung tumours can be visualised and sampled directly by biopsy and brushing using a flexible bronchoscope. Percutaneous needle biopsy under CT or ultrasound guidance; more reliable way to obtain a histological diagnosis for tumours which are too peripheral

Large cavitated bronchial carcinoma in left lower lobe

↓Adenocarcinoma Pan cost left lung↓ with Rib eroson

↓Pancost Right lung Pancostleft lung↓

MRI topCT lowerCavitySqu.carc

Management

Surgical resection carries the best hope of long-term survival; however, some patients treated with radical radiotherapy and chemotherapy also achieve prolonged remission or cure. Unfortunately, in over 75% of cases, treatment with curative intent is not possible, or is inappropriate due to extensive spread or comorbidity. Such patients can only be offered palliative therapy and best supportive care. Radiotherapy, and in some cases chemotherapy, can relieve distressing symptoms

Treatment and Staging NSCLC

Stage
Description
Treatment Options
Stage I a/b
Tumor of any size is found only in the lung
Surgery
Stage II a/b
Tumor has spread to lymph nodes associated with the lung
Surgery
Stage III a
Tumor has spread to the lymph nodes in the tracheal area, including chest wall and diaphragm
Chemotherapy followed by radiation or surgery
Stage III b
Tumor has spread to the lymph nodes on the opposite lung or in the neck
Combination of chemotherapy and radiation
Stage IV
Tumor has spread beyond the chest
Chemotherapy and/or palliative (maintenance) care

Surgical treatment

Accurate pre-operative staging, coupled with improvements in surgical and post-operative care, now offers 5-year survival rates of over 75% in stage I disease (N0, tumour confined within visceral pleura) and 55% in stage II disease, which includes resection in patients with ipsilateral peribronchial or hilar node involvement.

Contraindications to surgical resection in bronchial carcinoma

Distant metastasis (M1) Invasion of central mediastinal structures including heart, great vessels, trachea and oesophagus (T4) Malignant pleural effusion (T4) Contralateral mediastinal nodes (N3) FEV1 < 0.8 L Severe or unstable cardiac or other medical condition

Radiotherapy

While much less effective than surgery, radical radiotherapy can offer long-term survival in selected patients with localised disease in whom comorbidity precludes surgery. Continuous hyper-fractionated accelerated radiotherapy (CHART), in which a similar total dose is given in smaller but more frequent fractions, may offer better survival prospects than conventional schedules. The greatest value of radiotherapy, however, is in the palliation of distressing complications such as superior vena cava obstruction, recurrent haemoptysis, and pain caused by chest wall invasion or by skeletal metastatic deposits

Radiotherapy

. Obstruction of the trachea and main bronchi can also be relieved temporarily. can be used in conjunction with chemotherapy in the treatment of small-cell carcinoma, and is particularly efficient at preventing the development of brain metastases in patients who have had a complete response to chemotherapy

Chemotherapy

The treatment of small-cell carcinoma with combinations of cytotoxic drugs, sometimes in combination with radiotherapy, can increase the median survival from 3 months to well over a year. Combination chemotherapy leads to better outcomes than single-agent treatment. In particular, oral etoposide leads to more toxicity and worse survival than standard combination chemotherapy.

Chemotherapy

Regular cycles of therapy, including combinations of i.v. cyclophosphamide, doxorubicin and vincristine or i.v. cisplatin and etoposide, are commonly used. Nausea and vomiting are common side-effects and are best treated with 5-HT3 receptor antagonists


Chemotherapy
The use of combinations of chemotherapeutic drugs requires considerable skill and should be overseen by teams of expert clinicians and nurses. In general, chemotherapy is less effective in non-small-cell bronchial cancers. However, studies in such patients using platinum-based chemotherapy regimens have shown a 30% response rate associated with a small increase in survival.

Neoadjuvant and adjuvant chemotherapy

In non-small-cell carcinoma, there is some evidence that chemotherapy given before surgery may increase survival and can effectively 'down-stage' disease with limited nodal spread. Post-operative chemotherapy is now proven to improve survival rates when operative samples show nodal involvement by tumour.

Laser therapy and stenting

Palliation of symptoms caused by major airway obstruction can be achieved in selected patients using bronchoscopic laser treatment to clear tumour tissue and allow re-aeration of collapsed lung. The best results are achieved in tumours of the main bronchi. Endobronchial stents can be used to maintain airway patency in the face of extrinsic compression by malignant nodes

General aspects of management

The best outcomes are obtained when lung cancer is managed in specialist centres by multidisciplinary teams including oncologists, thoracic surgeons, respiratory physicians and specialist nurses; effective communication, pain relief and attention to diet are important. Lung tumours can cause clinically significant depression and anxiety, and these may need specific therapy. The management of non-metastatic endocrine manifestations is described in Chapter 20. When a malignant pleural effusion is present, an attempt should be made to drain the pleural cavity using an intercostal drain; provided the lung fully re-expands, pleurodesis with a sclerosing agent such as talc should be performed

Prognosis

The overall prognosis in bronchial carcinoma is very poor, with around 70% of patients dying within a year of diagnosis and only 6-8% of patients surviving 5 years after diagnosis. The best prognosis is with well-differentiated squamous cell tumours that have not metastasised and are amenable to surgical resection.

Secondary tumours of the lung

Blood-borne metastatic deposits in the lungs may be derived from many primary tumours, in particular the breast, kidney, uterus, ovary, testes and thyroid. The secondary deposits are usually multiple and bilateral. Often there are no respiratory symptoms and the diagnosis is made on radiological examination. Breathlessness may occur if a considerable amount of lung tissue has been replaced by metastatic tumour. Endobronchial deposits are uncommon but can cause haemoptysis and lobar collapse



Rare types of lung tumour
Tumour
Status
Histology
Typical presentation
Prognosis
Adenosquamous carcinoma
Malignant
Tumours with areas of unequivocal squamous and adeno-differentiation
Peripheral or central lung mass
Stage-dependent
Carcinoid tumour
Low-grade malignant
Neuroendocrine differentiation
Bronchial obstruction, cough
95% 5-year survival with resection
Bronchial gland adenoma
Benign
Salivary gland differentiation
Tracheobronchial irritation/obstruction
Local resection curative
Bronchial gland carcinoma
Low-grade malignant
Salivary gland differentiation
Tracheobronchial irritation/obstruction
Local recurrence occurs
Hamartoma
Benign
Mesenchymal cells, cartilage
Peripheral lung nodule
Local resection curative
Bronchoalveolar carcinoma
Malignant
Tumour cells line alveolar spaces
Alveolar shadowing, productive cough
Variable, worse if multifocal