Lung cancer that recurred as carcinoma en cuirasse.

Cutaneous metastasis from lung cancer is rare. We report an unusual cutaneous metastasis known as "carcinoma en cuirasse" 7 years after left upper lobectomy to treat an adenocarcinoma of the lung.

CLINICAL IMAGE

Cutaneous metastases of malignant tumours feature three main forms: Nodular, sclerodermoid (carcinoma en cuirasse), and inflammatory cancer. Carcinoma en cuirasse is an uncommon presentation of metastatic cutaneous carcinoma most often derived from a breast carcinoma. Such a cutaneous metastasis from lung cancer is extremely rare. We report on a 67‐year‐old male admitted to our hospital because of hard skin and itching 7 years after left upper lobectomy to treat non‐small cell lung cancer. Eight months prior, he had received radiation therapy to treat a left cervical lymph node metastasis. Extensive red‐to‐purple nodules with diffuse sclerodermoid indurations overlaid the precordial and back skin (Figure 1) (which lay outside the radiation field). The skin lesion was hard on palpation. A skin biopsy (Figure 2) revealed tumour cells invading the dermis that resembled the resected lung cancer (Figure 3). The lung cancer specimen stained positively for thyroid transcription factor and cytokeratin 7, whereas the skin biopsy stained for cytokeratin 7 only. The patient received nivolumab, ipilimumab, pemetrexed, and carboplatin, followed by decetaxel and ramucirumab; however, he died 3 months after presentation.

FIGURE 1

Clinical photograph showing the thickened cutaneous lesion of the anterior chest

FIGURE 2

Photograph of a stained biopsy slide showing diffuse infiltration of the dermis by solid adenocarcinoma tumour cells and glandular formation (black arrow) (H&E). The scale bar represents 100 μm

FIGURE 3

Photograph showing resected adenocarcinoma of the lung (H&E). The scale bar represents 100 μm

AUTHOR CONTRIBUTIONS

Shohei Nozu, Norihiko Nakanishi, and Yasushi Sadamoto performed medical treatment. Atsuro Sugita completed the pathological diagnosis. All authors have approved the final version of the manuscript submitted for publication.

CONFLICT OF INTEREST

None declared.

ETHICS STATEMENT

The authors declare that appropriate written informed consent was obtained for the publication of this manuscript and the accompanying images.