Respiratory

Lung Malignancies

Lung cancer

Introduction

  • Commonest malignancy in countries where people smoke. 1/3rd male cancer deaths,1/6th of female.
  • Screening asymptomatic smokers with regular CXR has not been shown to improve outcome.
  • 20% of smokers will develop lung cancer. The mean survival is 6 months

Pathology:  Histologically and Prognostically differentiated into

  • Small cell lung cancers (SCLC) 20%
    • Small cell or "Oat" cell - arise centrally metastasise early with micrometastases.
    • Arise from Kulchitsky cells of APUD system. Secrete peptide hormones.
  • Non small cell lung cancers (NSCLC) 80%
    • Adenocarcinoma 35% - Commonest. peripheral tumours
    • Squamous 25% central
    • Large cell 10%
    • Bronchoalveolar cell 5% - mucoid sputum

Aetiology

  • Smoking is by far the main cause
  • Occupational exposure - Asbestos, arsenic, nickel, silicosis, chromium, radon (and adenocarcinoma)
  • Commoner with Idiopathic pulmonary fibrosis and dermatomyositis
  • Greater in Urban rather than rural setting

Clinical

  • Mild/no symptoms or a slow to resolve pneumonia or a lesion found on CXR done for another cause.
  • Cough, sputum, haemoptysis, weight loss, Cachexia
  • Finger clubbing ? Hypertrophic osteoarthopathy (non small cell)
  • Chest - Consolidation, collapse or pleural effusion
  • Cervical or supraclavicular lymphadenopathy.
  • Local effects - SVC obstruction, Hoarseness (Recurrent laryngeal nerve)
  • Chest or shoulder pain due to infiltration of brachial plexus
  • Horner's syndrome ? infiltration of sympathetic chain and 1st and 2nd rib can be involved as well as shadow at lung apex
  • Neurological - Cerebral metastases - weakness, focal seizures, altered personality, lateralising signs
  • Cerebellar signs or brainstem encephalitis due to metastasises or immunological (anti-Hu or anti-Yo antibodies) paraneoplastic, Peripheral neuropathy
  • Endocrine - Hyponatraemia due to SIADH from small cell, Hypercalcaemia ? Non small cell, Cushing?s syndrome from ACTH secretion by small cells
  • Paraneoplastic phenomena where distal effects not due to tumour cells themselves are manifest without tumour spread.
  • Seen with
    • ACTH release and Cushingoid appearance
    • Lambert Eaton syndrome
    • SIADH
    • Hypercalcaemia due to PTH related peptide release
    • Clubbing and HPOA
    • Cerebellar degeneration

Investigations

  • FBC, U&E, LFTs, Calcium and sputum cytology
  • CXR is often diagnostic followed by Bronchoscopy for a central lesion to get a tissue biopsy
  • For peripheral lesions a CT guided percutaneous needle biopsy is preferable
  • CT chest/liver/adrenals and brain if Symptoms.
  • Greater use of PET scanning to identify disease as it is more sensitive and specific than CT for identifying disease and can be combined with CT

Management

  • Initial staging by CT which involves thorax and may include brain and adrenals looking for spread
  • Decisions are made by using a multidisciplinary team involving respiratory physicians, specialist nurses, oncologists and surgeons and palliative care teams and the patient.
  • Underlying Performance status which includes lung function is important if operability is considered.

Non small cell

  • Non small cell tumours staged as Tumour/nodes/metastasis (TNM) system. Localised tumours may be considered for surgery. Cure is possible. Those unfit may received radiotherapy. Chemotherapy may be offered as a palliative.
  • Surgery is the best chance for cure and all patients with Stage I or II disease should be considered for curative surgery. Different options include wedge resection, lobectomy and pneumonectomy.
  • Staging for NSCLC
    • Stage I : Mass < 3 cm confined to bronchus with no nodes
    • Stage II : Mass > 3 cm in Bronchus with nodes/chest wall or diaphragm
    • Stage III : Involves mediastinal nodes or sub carinal nodes or hilar nodes other or any other local infiltration
    • Stage IV : Distant metastases
    • Contraindications to surgical resection - Liver metastasis, Pancoast tumour, Malignant pleural effusion, FEV < 1.5 L, Vocal cord paralysis, SVC obstruction
  • Small cell
    • Small cell tumour staged as limited to one hemithorax or widely disseminated. Untreated prognosis is 2 months.
    • Chemotherapy can induce remission and increase survival to almost 18 months.
  • Inoperable disease can be treated with palliative radiotherapy and sometimes chemotherapy
  • Severe hypercalcaemia - Rehydrate, IV N-Saline, IV Pamidronate
  • SVC obstruction - radiotherapy and stenting

Miscellaneous

Haemoptysis

Introduction

  • Many causes - get a CXR, smoking history, TB?

Aetiology

  • Usually when severe is from systemic pressure bronchial arterial supply
  • Massive haemoptysis (> 600 ml/day)

Clinical

  • Ask about smoking, weight loss, clubbing, TB, bleeding disorder, Cystic fibrosis or bronchiectasis, HIV.

Investigations

  • Check FBC, U&E, Clotting screen
  • Arterial blood gas
  • CXR is vital and can quickly identify a lung lesion
  • CT chest may be helpful and CT-PA if PE suspected
  • Bronchoscopy preferably rigid may be useful if bleeding not massive to look disease
  • cANCA if Wegener's suspected, Anti-GBM if Goodpasture's suspected

Management

  • Those in extremis involves ABCs give Oxygen and consider nebulized adrenaline 5-10 ml of 1 in 10,000
  • Lie patient on their bleeding side (determined with CXR) as this helps aerate and protect the good lung
  • Large bore IV cannula or two - Group and cross match check clotting and transfuse
  • Fluid replacement, antitussive, sedation, correct clotting e.g warfarin
  • Consider oral tranexamic acid 500 mg tds - cautions in renal failure
  • Next steps will depend on likely cause.
  • Bronchial artery angiography and embolisation should be considered and attempted if indicated.
  • Fibreoptic bronchoscopy is usually futile in severe cases as blood obscures view and may need to consider intubation with double lumen tube
  • Discuss with local respiratory team and cardiothoracic as surgery indicated in unresponsive cases
  • If terminal lung cancer then palliation may be more appropriate with diamorphine