Combined large‑cell neuroendocrine carcinoma and small‑cell lung cancer: A case report

Abstract

Combined large-cell neuroendocrine carcinoma (LCNEC) and small-cell lung cancer (SCLC) is extremely rare, with only a few reports available in the literature. An accurate diagnosis is difficult to make due to the overlapping clinical features between LCNEC and SCLC, and a standardized treatment option is lacking. A 53-year-old female patient was admitted to Xiaoshan Affiliated Hospital of Wenzhou Medical University (Hangzhou, China) due to symptoms of dyspnea and phlegm, with blood in the sputum. Computed tomography revealed a 52×32×26-mm irregular soft-tissue mass in the left upper lung. Pathological examination of the biopsy specimen showed a poorly differentiated neuroendocrine carcinoma with compression injury, consistent with a mixed type of large and small cell carcinoma. The patient was administered chemotherapy, radiotherapy and targeted therapy, and as of October 2023, the patient had a survival period of 29 months. LCNEC combined with SCLC is a sporadic tumor with a high potential for malignancy. Multidisciplinary treatment and close follow-up are recommended. The multidisciplinary treatment strategy used in the present study is expected to help inform future therapeutic decisions.

Keywords: case report; chemotherapy; immunotherapy; large cell neuroendocrine carcinoma; local radiotherapy; multidisciplinary treatment; pathology; small cell lung cancer.

Figure 1.

CT images of the patient. (A) A soft-tissue mass in the left lung was shown in a chest CT scan performed in June 2021. (B) The mass had decreased after radiotherapy, as detected in September 2021. (C) The mass showed progression after chemotherapy, as detected in December 2021. (D) There was no progression of the mass in October 2023. CT, computed tomography.

Figure 2.

Lung pathology of the patient. (A) Left lung tissues were positive for small and large malignant cells (hematoxylin and eosin staining; ×200 magnification). The left side of the diagram shows the large cells (~10%) and the right side shows the small cells (~90%) with crush injury. Immunohistochemical staining of (B) CD56, (C) synaptophysin, (D) chromogranin A, (E) Ki-67, (F) thyroid transcription factor-1 and (G) cytokeratin (all ×200 magnification).

Figure 3.

MRI of the patient. The left parietal occipital, left skull base meninges, and the top and left walls of the nasopharynx showed thickening. (A) T1WI, (B) T2WI and (C) contrast-enhanced MRI. WI, weighted imaging; MRI, magnetic resonance imaging.

Figure 4.

(A) Nasopharyngeal mass tissues were positive for small and large malignant cells (hematoxylin and eosin staining; ×200 magnification). The left side of the diagram shows the large cells and the right side shows the small cells with crush injury. Immunohistochemical staining of (B) CD56, (C) synaptophysin, (D) Ki-67, (E) chromogranin A, (F) cytokeratin 7, (G) cytokeratin (all ×200 magnification), (H) neuron-specific enolase (×100 magnification) and (I) thyroid transcription factor-1 (×200 magnification).