Cutaneous metastasis as an initial presentation of lung adenocarcinoma with KRAS mutation: a case report and literature review

Cutaneous metastasis as a first presentation of lung carcinoma: a case series

INTRODUCTION

Cutaneous metastases (CM) revealing lung carcinoma are extremely rare, accounting for 0.8%. The diagnosis is guided by histology and immunohistochemistry. Treatment is palliative. The prognosis is poor.

CASE PRESENTATION

This is a retrospective study of the available clinical and histological records of four North African patients with CM revealing lung cancer treated at our institute between 2004 and 2010. Three men and one woman were registered. The mean age was 54.5 years (38-74 years). Two patients had primary adenocarcinoma, one patient had small cell carcinoma and one had squamous cell carcinoma. Treatment was based on chemotherapy in two cases and antalgic radiotherapy in two cases, one patient underwent surgical resection as the lesion was infected. The overall survival after diagnosis was between one and four months.

CONCLUSIONS

A skin nodule can be the first symptom revealing lung cancer. A rare clinical presentation that should not be taken for a benign nodule, the biopsy and histological study with immunohistochemistry confirm the diagnosis.

Cutaneous Metastasis from Lung Adenocarcinoma

Cutaneous metastases are rare and often portend the aggressive malignancy and poor prognosis. We report a case of a 62-year-old man with a rapidly growing nodule on the left back for 2 months. The patient was diagnosed with lung adenocarcinoma shortly before the skin lesion presented. Physical examination showed a dome-shaped purplish red nodule, with ulceration and hemorrhagic crust. Excision of the skin lesion was performed, and the histopathology showed tumor cells infiltrate with immunohistochemistry (TTF-1+CK7+CD20–) favoring primary lung adenocarcinoma.

Cutaneous Metastasis as the First Presentation of Non-Small-Cell Lung Cancer with a BRAF Mutation: A Case Report

Cutaneous metastasis from a primary visceral malignancy is a relatively uncommon clinical manifestation that occurs as an initial presentation in 1% to 12% of patients with internal malignancies. Additionally, cutaneous metastases are often late signs of an internal malignancy, and in very rare cases they may occur at the same time or before the primary cancer has been detected. Metastasis to the skin has a poor prognosis and is often a sign of widespread malignant tumors. In the present study, we report a 72-year-old male who presented with multiple rapidly growing subcutaneous nodules. Positron emission tomography-computed tomography (PET-CT) revealed a hypermetabolic concentration of radiotracer in the left lower lung and multiple organ metastases associated with multiple skin masses. Biopsy of one of the skin nodules and gene detection indicated metastatic adenocarcinoma consistent with a primary lung origin with a BRAF mutation. BRAF mutations are emerging therapeutic targets in non-small-cell lung cancer (NSCLC), as they are present in 2–4% of NSCLC cases. To the best of our knowledge, this is the first case report to show that BRAF-mutant lung adenocarcinoma can be associated with cutaneous metastasis. Early diagnosis and individualized treatment strategies may prolong patient survival.

Cutaneous metastases as a presenting sign of metastatic NSCLC

Cutaneous metastases are rare and often late signs of an internal malignancy; however, this can be the presenting sign in very rare cases. These typically have a characteristic appearance and distribution based on the underlying malignancy but can be difficult to distinguish from other malignant or benign dermatoses. We report a case of a 69-year-old female who presented for elective excision of two cutaneous, fast-growing lesions on the chest wall. The patient's past medical history is significant for a 45-pack-year smoking history. Pre-operative chest radiograph revealed a right upper lobe mass, with the lesions ultimately representing cutaneous metastases of a non-small-cell lung cancer. Although cutaneous metastases have been reported, difficulty remains in distinguishing other causes of cutaneous lesions from cutaneous metastases in the predominantly asymptomatic patient.

Non-small cell lung cancer with distal cutaneous metastases in a patient with a previously treated colorectal carcinoma

Cutaneous manifestations of visceral carcinomas are scarce, occurring in around 0.7-12% of internal malignancies. Lung cancer is one of the most common sources of skin metastasis, particularly in male patients. We present a case of cutaneous metastasis in a man with concurrent lung lesions and a previously treated colorectal carcinoma. Immunohistochemistry markers for both skin and lung lesions were strongly positive for carcinoembryonic antigen and cytokeratin 20, suggesting an intestinal primary tumour. However, colonoscopy excluded new and metastatic bowel lesions. After multidisciplinary team meetings, which reviewed the clinical, radiological and immunohistochemistry findings, it was concluded to be a non-small cell lung cancer with skin metastasis. This case presented an interesting diagnostic challenge, and highlighted the importance of cross-specialty liaison and investigation to reach the correct diagnosis.