A Case of Primary Combined Squamous Cell Carcinoma with Neuroendocrine (Atypical Carcinoid) Tumor in the Floor of the Mouth. Case Rep Dent. 2016;2016:7532805. [PMID: 28116178 PMCID: PMC5223000 DOI: 10.1155/2016/7532805]

Primary Oral Mixed Neuroendocrine-Non-neuroendocrine Neoplasm (MiNEN): A Rare Case Report and Review of the Literature

Mixed neuroendocrine-non-neuroendocrine neoplasms (MiNENs) are rare tumors recently characterized by the presence of both neuroendocrine and non-neuroendocrine components within the same tumor tissue. Although MiNEN found their place in the WHO classification for various organs, this composite tumor in the head and neck region remains exceptionally rare. We present a case of primary oral MiNEN in a 64-year-old male located on the left side of lower gingiva. Biopsy raised suspicion of neuroendocrine carcinoma (NEC) and the patient underwent partial mandibulectomy. The resected specimen showed two distinct components of NEC and squamous cell carcinoma (SCC) with the confirmation of immunohistochemical markers. There has been no sign of recurrence nor metastasis 6 years after the surgery. In addition, we have conducted a review of published cases with potential relevance to this entity, resulting in five cases. The diverse terminology reinforces the need for a standardized classification system of oral/head and neck MiNENs.

Synchronous Multiple Primary Cancers of the Lung: The Rare Association of Non-Small Cell Carcinoma With a Carcinoid Tumor

A 68-year-old female patient diagnosed with lung cancer in the left upper lobe with associated mediastinal adenopathy. The cancer was pathologically diagnosed as stage pT1bN0 typical carcinoid. Investigation of the mediastinal lymph nodes revealed an isolated metastatic non-small cell squamous cell carcinoma (NSCLC). A primary NSCLC was not found. The patient underwent successful surgical resection of both synchronous tumors, with no residual disease or recurrence. This case not only expands the histological field of combined neuroendocrine tumors, but it also highlights the importance of distinguishing various tumor types for disease treatment and prognosis.

Collision tumor of squamous cell carcinoma and neuroendocrine carcinoma in the head and neck: A case report

BACKGROUND

There are many disputes about the definition, diagnosis, therapy, and prognosis of collision tumors.

CASE SUMMARY

We describe a rare patient with a collision tumor consisting of neuroendocrine carcinoma (NEC) and squamous cell carcinoma (SCC) in the nasal cavity and paranasal sinus. She received operation, concurrent chemoradiotherapy, and then two cycles of palliative chemotherapy. Follow-up at 12 mo after diagnosis showed that this patient experienced a complete response with no signs of recurrence or metastasis. A literature review of previous 26 cases diagnosed with collision tumor of NEC and SCC in the head and neck was also undertaken.

CONCLUSION

It is challenging to manage collision tumors because there are two morphologically and etiologically distinct tumors. Well-designed multimodality therapy including surgery and chemoradiotherapy might lead to a long survival in these patients.

Lineage plasticity in cancer: a shared pathway of therapeutic resistance

Lineage plasticity, the ability of cells to transition from one committed developmental pathway to another, has been proposed as a source of intratumoural heterogeneity and of tumour adaptation to an adverse tumour microenvironment including exposure to targeted anticancer treatments. Tumour cell conversion into a different histological subtype has been associated with a loss of dependency on the original oncogenic driver, leading to therapeutic resistance. A well-known pathway of lineage plasticity in cancer - the histological transformation of adenocarcinomas to aggressive neuroendocrine derivatives - was initially described in lung cancers harbouring an EGFR mutation, and was subsequently reported in multiple other adenocarcinomas, including prostate cancer in the presence of antiandrogens. Squamous transformation is a subsequently identified and less well-characterized pathway of adenocarcinoma escape from suppressive anticancer therapy. The increased practice of tumour re-biopsy upon disease progression has increased the recognition of these mechanisms of resistance and has improved our understanding of the underlying biology. In this Review, we provide an overview of the impact of lineage plasticity on cancer progression and therapy resistance, with a focus on neuroendocrine transformation in lung and prostate tumours. We discuss the current understanding of the molecular drivers of this phenomenon, emerging management strategies and open questions in the field.

Collision carcinoma of squamous cell carcinoma and small cell neuroendocrine carcinoma of the larynx: A case report and review of the literature

BACKGROUND

Collision carcinoma is rare in clinical practice, especially in the head and neck region. In this paper, we report a case of squamous cell carcinoma (SCC) and neuroendocrine carcinoma (NEC) colliding in the larynx and review 12 cases of collision carcinoma in the head and neck to further understand collision carcinoma, including its definition, diagnosis, and treatment.

CASE SUMMARY

A 61-year-old man presented with a 1-year history of hoarseness. Contrast-enhanced magnetic resonance imaging of the larynx revealed that the right vocal cord had a nodule-like thickening with obvious enhancement. Laryngoscopy revealed a neoplasm on the right vocal cord, and a malignant tumor was initially considered. A frozen section of right vocal cord was performed under general anesthesia. The pathological result showed a malignant tumor in the right vocal cord. The tumor was excised with a CO₂ laser (V_c type). Routine postoperative pathology showed moderately differentiated SCC with small cell NEC in the right vocal cord. No metastatic lymph nodes or distant metastases were found on postoperative positron emission tomography/computed tomography. Because of the coexistence of SCC and NEC, the patient received adjuvant chemotherapy and radiotherapy. The patient was followed for 8 mo, and no recurrence or distant metastasis was found.

CONCLUSION

The treatment of collision carcinoma in the head and neck region is uncertain due to the small number of cases.