Successful Treatment of a Mixed Neuroendocrine-Nonneuroendocrine Neoplasm of the Colon with Metastases to the Thyroid Gland and Liver. Case Rep Otolaryngol. 2020;2020:5927610. [PMID: 32099708 PMCID: PMC7040413 DOI: 10.1155/2020/5927610]

Thyroid gland: a rare site of metastasis

PURPOSE

Despite its rich vascularity, metastasis (MTS) to the thyroid tissue is unusual, ranging from 1 to 3%. This entity is not usually considered as differential diagnosis and is not included in the upfront approach in patients with thyroid nodules. Once diagnosed, treatment is controversial. The aim of this study was to evaluate diagnosis, treatment, and outcome at the end of follow-up in patients with a diagnosis of MTS to the thyroid.

METHODS

A retrospective multicenter study was designed from 1985 to 2022; 29 patients with MTS to the thyroid gland were included in the analysis.

RESULTS

Clinical presentation included the presence of a nodular goiter (65.5%), compression symptoms (17.2%), diffuse goiter (10.3%), and suspicious lymph nodes in the neck (7%). Primary tumor sites were: kidney (44.8%), breast (24.1%), lung (13.8%), neuroendocrine system (6.9%), colon (3.4%), cervix (3.4%), and ovary (3.4%). In 18/23 patients, suspicious ultrasound criteria for malignancy were described. Preoperative diagnosis was made in 23/27 patients by FNA and confirmed in 18 cases by immunohistochemistry. Seventeen patients underwent surgery. At the end of the follow-up, 19 patients had died of oncological disease, and six were alive (2/6 disease-free with isolated intrathyroidal MTS).

CONCLUSION

Renal carcinoma was the tumor that most frequently metastasized to the thyroid gland. Immunodiagnosis was a very useful tool for etiological confirmation. Patients with MTS to the thyroid gland as a unique site had a more favorable course compared to patients with multiple metastatic sites. Finally, outcomes and prognosis essentially depended on the biology of the primary tumor.

Combined Neuroendocrine and Squamous Cell Carcinoma of the Sinonasal Tract: A Morphologic and Immunohistochemical Analysis and Review of Literature

Sinonasal malignancies constitute 3% of head and neck cancers, with squamous cell carcinoma (SCC) the most common histology. Neuroendocrine carcinomas (NEC) are rare, with a subset showing neuroendocrine carcinoma and a non-neuroendocrine component. The pathogenesis of these combined tumors is largely unknown, and TP53 driver mutations may play a role. A database search for combined NEC was performed across two institutions (UNM and UCSF) spanning 15 years. Excluding NUT midline carcinoma, 3 cases met inclusion criteria. All were morphologically NEC + SCC and underwent a comprehensive immunohistochemical evaluation. Tumors demonstrated two components histologically: moderately to poorly differentiated SCC and high-grade NEC. Divergent differentiation was confirmed with lineage-specific markers. Only one patient received neoadjuvant chemotherapy prior to surgery, with a remarkable response (a marked decrease in the size of the primary lesion and resolution of liver metastases). Immunohistochemical staining for p53 was increased in 2 of 3 cases (both components), suggesting a role in the carcinogenesis of these tumors. Aberrant expression of beta-catenin was not identified. One case tested positive for p16, which can be seen in high grade NECs due to inactivation of Rb gene. Additionally, both cases with a small cell NEC component expressed PD-L1, suggesting that immunotherapy may be an effective treatment. Findings in this study support the role of p53 mutation in a subset of combined NEC + SCC of the sinonasal tract. Recognition of this rare entity is essential for optimal management of these aggressive neoplasms.

When Variants Collide: An Unusual Presentation of Metastatic Gastric Mixed Neuroendocrine-Non-Neuroendocrine Neoplasm

Gastrointestinal neuroendocrine neoplasms were recently reclassified into the 2019 World Health Organization schema into well-differentiated neuroendocrine tumors, poorly differentiated neuroendocrine carcinomas, and mixed neuroendocrine-non-neuroendocrine neoplasms (MiNENs). Among these, gastric MiNENs are exceedingly rare and often metastasize quickly without diagnostic clues. We present a refractory gastric MiNEN with unique presenting features. This case highlights the clinical spectrum of these tumors, the importance of accurate histochemical interpretation, and clinical management in the absence of formalized guidelines. Future therapies looking at novel targets and palliative symptom relief are needed.

Clinicopathological features and prognostic factors associated with gastroenteropancreatic mixed neuroendocrine non-neuroendocrine neoplasms in Chinese patients

BACKGROUND

The incidence of mixed neuroendocrine-non-neuroendocrine neoplasms (MiNEN) is low. To improve our understanding of this rare tumor type and optimally guide clinical treatment, associated risk factors, clinical manifestations, and prognosis must be explored.

AIM

To identify risk factors that influence the prognosis of patients with gastroenteropancreatic MiNEN (GEP-MiNEN).

METHODS

We retrospectively analyzed the clinical data of 46 patients who were diagnosed with GEP-MiNEN at the First Affiliated Hospital of Bengbu Medical College (Anhui, China) between January 2013 and December 2017. Risk factors influencing the prognosis of the patients were assessed using Kaplan-Meier curves and cox regression models. We compared the results with 55 randomly selected patients with gastroenteropancreatic GEP neuroendocrine tumors, 47 with neuroendocrine carcinomas (NEC), and 58 with poorly differentiated adenocarcinoma.

RESULTS

Among the 46 patients with GEP-MiNEN, thirty-five had gastric tumors, nine had intestinal tumors (four in the small intestine and five in the colon and rectum), and two had pancreatic tumors. The median age of the patients was 66 (41-84) years, and the male-to-female ratio was 2.83. Thirty-three (71.7%) patients had clinical stage III and IV cancers. Distant metastasis occurred in 14 patients, of which 13 had metastasis to the liver. The follow-up period was 11-72 mo, and the median overall survival was 30 mo. Ki-67 index ≥ 50%, high proportion of NEC, lymph node involvement, distant metastasis, and higher clinical stage were independent risk factors affecting the prognosis of patients with GEP-MiNEN. The median overall survival was shorter for patients with NEC than for those with MiNEN (14 mo vs 30 mo, P = 0.001), but did not significantly differ from those with poorly differentiated adenocarcinoma and MiNEN (30 mo vs 18 mo, P = 0.453).

CONCLUSION

A poor prognosis is associated with rare, aggressive GEP-MiNEN. Ki-67 index, tumor composition, lymph node involvement, distant metastasis, and clinical stage are important factors for patient prognosis.

Mixed epithelial endocrine neoplasms of the colon and rectum – An evolution over time: A systematic review

BACKGROUND

Mixed tumors of the colon and rectum, composed of a combination of epithelial and endocrine elements of benign and malignant potential are rare neoplasms. These can occur anywhere in the gastrointestinal tract and are often diagnosed incidentally. Though they have been a well-documented entity in the pancreas, where the exocrine-endocrine mixed tumors have been known for a while, recognition and accurate diagnosis of these tumors in the colon and rectum, to date, remains a challenge. This is further compounded by the different terminologies that have been attributed to these lesions over the years adding to increased confusion and misclassification. Therefore, dedicated literature reviews of these lesions in the colon and rectum are inconsistent and are predominantly limited to case reports and case series of limited case numbers. Though, most of these tumors are high grade and of advanced stage, intermediate and low grade lesions of these mixed tumors are also increasingly been reported. There are no established independent consensus based guidelines for the therapeutic patient management of these unique lesions.

AIM

To provide a comprehensive targeted literature review of these complex mixed tumors in the colon and rectum that chronicles the evolution over time with summarization of historical perspectives of terminology and to further our understanding regarding their pathogenesis including genomic landscape, clinicoradiological features, pathology, treatment, prognosis, the current status of the management of the primary lesions, their recurrences and metastases.

METHODS

A comprehensive review of the published English literature was conducted using the search engines PubMed, MEDLINE and GOOGLE scholar. The following search terms [“mixed tumors colon” OR mixed endocrine/neuroendocrine tumor/neoplasm/lesion colon OR adenocarcinoma and endocrine/neuroendocrine tumor colon OR mixed adenocarcinoma and endocrine/neuroendocrine carcinoma colon OR Amphicrine tumors OR Collision tumors] were used. Eligibility criteria were defined and all potential relevant items, including full articles and/or abstracts were independently reviewed, assessed and agreed upon items were selected for in-depth analysis.

RESULTS

In total 237 full articles/abstracts documents were considered for eligibility of which 45 articles were illegible resulting in a total of 192 articles that were assessed for eligibility of which 139 have been selected for reference in this current review. This seminal manuscript is a one stop article that provides a detailed outlook on the evolution over time with summarization of historical perspectives, nomenclature, clinicoradiological features, pathology, treatment, prognosis and the current status of the management of both the primary lesions, their recurrences and metastases. Gaps in knowledge have also been identified and discussed. An important outcome of this manuscript is the justified proposal for a new, simple, clinically relevant, non-ambiguous terminology for these lesions to be referred to as mixed epithelial endocrine neoplasms (MEENs).

CONCLUSION

MEEN of the colon and rectum are poorly understood rare entities that encompass an extensive range of heterogeneous tumors with a wide variety of combinations leading to tumors of high, intermediate or low grade malignant potential. This proposed new revised terminology of MEEN will solve the biggest hurdle of confusion and misclassification that plagues these rare unique colorectal neoplasms thus facilitating the future design of multi institutional prospective randomized controlled clinical trials to develop and evaluate newer therapeutic strategies that are recommended for continued improved understanding and personal optimization of clinical management of these unique colorectal neoplasms.