ADVANCED BRONCHOGENIC CARCINOMA PRESENTING WITH SKIN NODULES – A CASE REPORT

Abstract

Bronchogenic cancer can metastasize to several organs of the body. Metastases to skin and subcutaneous tissue are uncommon. We present our experience with the management of a patient with an unusual presentation of bronchogenic carcinoma with multiple skin nodules. In patients with bronchogenic cancer, metastasis to the skin and subcutaneous tissues could heighten the index of suspicion of advanced disease. The nodules should be histologically assessed and if confirmed metastatic, only palliative therapies are indicated.

Introduction

Bronchogenic carcinoma is known globally as one of the most frequent malignancies with high mortality rate, about 19.4% deaths per year1. It can metastasize to several organs in the body, but more frequently to the hilar nodes, bones, brain, liver, and adrenal glands2. However, metastases to skin, subcutaneous tissues and other soft tissues are uncommon3. Overall prevalence of soft tissue metastasis from bronchogenic carcinoma is 2.3%4 while autopsy series have reported soft tissue metastasis of about 0.75–9%5. Almost all histological types of carcinoma of the lung metastasize to the skin and subcutaneous tissues. This may at times be the first sign of bronchogenic carcinoma. These nodules may not be clinically distinguishable from skin metastases of primary cancers from other organs6. Most common sites of skin metastases from bronchogenic carcinoma are the chest, abdomen, head and neck6. They appear as mobile or fixed, oval or round nodules, firm, skin-coloured (sometimes black), usually painless and may rarely appear in group or solitary papules7. The occurrence of cutaneous metastases from bronchogenic carcinoma is an indicator of a poor prognosis8. We present a case of adenocarcinoma of the lung with skin and subcutaneous metastasis.

CASE REPORT

A 45-year old teacher admitted through the outpatient clinic presented with 3 months’ history of cough and difficulty with breathing, and multiple subcutaneous nodules of one-month duration. Cough was insidious in onset, productive of small volume odourless whitish sputum which was occasionally blood stained and not related to postural variation. There was no associated history of fever, night sweats, chest pain, orthopnoea or paroxysmal nocturnal dyspnoea. There was no history of exposure to dusty environments, smoke, pollens, contact with anyone with chronic cough. Difficulty in breathing started about the same time, and worsened on mild exertion but relieved by rest. No generalised body swelling, wheezing or bluish discoloration of the lips and other parts of the body. The subcutaneous nodules were noted to erupt one after the other in crops, no significant change in size except a few of them. There was history of significant weight loss as evidenced by loosening of previously fitting clothing, associated with loss of appetite. He was however treated empirically for pulmonary tuberculosis about 5 years ago at another facility for only 3 months. There was a history of cigarette smoking. Cumulative tobacco use was less than one pack years and he stopped 15 years ago. No history of intake of alcohol beverages. He had a chest X-ray which showed homogenous opacity of the right hemi-thorax, deviation if the trachea to the ipsilateral side with air bronchogram.

Clinical Examination revealed a chronically ill-looking middle-aged man in moderate respiratory distress, with multiple cutaneous and subcutaneous nodules on the anterior chest wall, back and arms - sizes ranging from 2 to 15mm. He was mildly pale, well hydrated, no digital clubbing and no pedal edema. There was an obvious chest wall asymmetry with flattening of the right hemi-thorax while the left hemi-thorax was prominent (Fig. 1) and the trachea was deviated to the right. There was reduced chest expansion, tactile fremitus, air entry and dull percussion notes on the right hemi-thorax, while on the left hemi-thorax tactile fremitus was normal, percussion notes were hyper resonant with good vesicular breath sounds. A diffuse cardiac activity was noted over the right parasternal region with apex beat and normal first and second heart sounds heard loudest at the right lower parasternal boarder with a soft systolic murmur. Other systemic examinations were normal.

Fig. 1. Flattened right hemithorax, skin nodule (black arrow) and subcutaneous nodules (red arrow).

Chest X-ray showed a trachea deviation to the right, collapsed right lung and compensatory hyperinflation of the left lung with cardiac silhouette completely on the right hemi-thorax. The chest CT scan revealed a completely destroyed and collapsed right lung parenchyma, heart completely in the right hemi-thorax and some hypo-dense lesions in the liver (Fig. 3); the sputum GeneXpert was negative.

Fig. 3. Chest CT scan showing hyper inflated left lung (A), collapsed and consolidated right lung tissue (yellow arrow), heart shifted to the right (blue arrow) and multiple hypodense lesion in the liver (red arrow).

After optimization, the patient was scheduled for subcutaneous node biopsy and open lung biopsy via mini lateral thoracotomy. Bronchoscopy and thoracoscopy were not available in our facility as at the time of care. Intraoperative findings were completely destroyed and collapsed right lungs with thick mucoid grey coloured discharge from the destroyed tissue and bronchus (Fig. 4). Right pneumonectomy was done and the large subcutaneous nodules biopsied. Post-operative condition was satisfactory as symptoms improved within a week after surgery and minimal mediastinal alteration on post-operative chest x-ray (Fig. 2)

Fig. 4. Resected destroyed right lung tissue.

Fig. 2. Preoperative and post operative Chest Radiograph.

Histology of resected lung tissue was poorly differentiated carcinoma, and the subcutaneous nodules were reported as well differentiated metastatic adenocarcinoma. Immunohistochemistry would advise further treatment. Patient was followed up for one month during which he had improvement in peripheral oxygen saturation. He has not kept any of his subsequent appointments and is presumed lost to follow up.

Discussion

Metastases from bronchogenic carcinoma to subcutaneous tissue and skin are uncommon. There are no definite management guidelines for patients with soft tissue metastases of lung origin9,10. About half of the cases are metastatic at the time of diagnosis, and 60% of patients have microscopic or clinically evident metastasis at the time of commencement of primary tumour treatment11. Major sites of metastases include liver (33-40%), abdominal lymph nodes (29%), bone (19-33%), adrenal glands (18-38%), kidney (16-23%), and brain (15- 43%)12,13. Reported cases have shown low prevalence of cutaneous metastases in patients with primary lung carcinoma (1.3-4%)14. However, subclinical metastases may be more frequent than commonly expected11. Nguyen and colleagues5 noted that the prevalence of soft tissues metastasis originating from lung carcinoma (2.3%) was much lower compared with that of melanoma (9.8%). The commonest presenting symptom of the cutaneous metastasis is pain (83%), followed by palpable masses 78% which may be found incidentally15. Other modes of presentation include painless soft tissue lump in patients with occult primary tumours,9 asymptomatic masses, accidental diagnosis after a trauma involving the affected area, weight loss or a single metastasis in a patient with unknown tumour16. Peripherally arising non-small-cell lung carcinoma like adenocarcinoma could also present without pulmonary symptoms17. The size of the lesion usually ranges between 1 and 20 cm (median of 6 cm)15. Commonly reported locations of skin and subcutaneous metastases include the back, chest wall, scalp and abdomen10, 18, 19.

The treatment of skin and subcutaneous metastases depends on their clinical presentation, location and prognosis related to the primary lung tumour. Painful masses are usually treated with palliative radiotherapy or chemotherapy or both. This may be indicated based on the primary lung tumour, the other organs involved and the extent of involvement, the patient’s age, health status and the aim of the therapy17. Radiotherapy has been shown to be effective in controlling pain and size of the lesion, but can cause complications such as burns and muscle contractures18.

The histological confirmation of skin metastases influences the treatment of the primary lung tumour. For carcinoma of the lungs, surgical excision of the primary lesion is not indicated because curative treatment is not feasible, and the patient is usually treated with chemotherapy only5. Available evidence showed that the survival of patients with soft tissues metastases ranges from about 9 to 36 months after the diagnosis of the mass, although in some cases survival up to 5 years has been reported17. The presence of a skin metastasis in bronchogenic carcinoma indicates a poor prognosis, with a median survival of 2-4 months19, 20, 21. In patients with bronchogenic cancer, metastasis to the skin and subcutaneous tissues are uncommon and should heighten the index of suspicion of advanced disease. The nodules should be histologically assessed and if confirmed metastatic, only palliative therapies are indicated.