Alpha–fetoprotein elevation in NUT midline carcinoma: a case report
© The Author(s). 2017
Received: 21 September 2016
Accepted: 4 April 2017
Published: 13 April 2017
Nuclear protein in testis (NUT) midline carcinoma is a rarely diagnosed and potentially under-recognized type of squamous carcinoma that is considered one of the most aggressive human solid tumors. Alpha-fetoprotein elevation has been associated with chronic liver diseases and a limited number of cancers. In particular, in presence of a mediastinal mass in a young man, alpha-fetoprotein elevation is considered nearly pathognomonic of a non-seminoma germ-cell tumor.
A 22-year old man without any comorbidity was diagnosed with a large mediastinal mass with skeletal and lymph node metastases. The clinical picture was dominated by a life-threatening superior vena cava syndrome with elevated alpha-fetoprotein and lactate dehydrogenase that supported the diagnostic suspicion of mediastinal germ-cell tumor. However, a biopsy showed a poorly-differentiated and diffusely necrotic carcinoma. We eventually reached the diagnosis of the peculiar entity of NUT midline carcinoma, but the differential diagnosis was quite challenging also because alpha-fetoprotein is not reported as a marker of NUT midline carcinoma. Notably, alpha-fetoprotein levels correlated with disease course.
The life-threatening aggressiveness of NUT midline carcinoma mandates to reach the right diagnosis in the shortest possible time. In this regard, poorly differentiated carcinomas lacking glandular differentiation mandate testing for NUT expression by immunohistochemistry. Awareness of a potentially misleading tumor marker elevation can help to broaden the differential diagnosis and establish the most appropriate treatment.
KeywordsNUT midline carcinoma Mediastinal mass Alpha–fetoprotein Case report
Nuclear protein in testis (NUT) midline carcinoma is an exceedingly rare subtype of squamous poorly–differentiated carcinoma and is considered one of the most aggressive human solid tumors [1–3]. NUT midline carcinoma is a relatively new entity, that may likely be under–recognized and under–diagnosed. All ages and organs might be affected, but most frequently NUT midline carcinoma arises along the trunk or the head and, in particular, in midline structures such as the mediastinum [1–3]. NUT midline carcinoma is characterized by the pathognomonic chromosomal rearrangement between the NUT gene with either bromodomain–containing protein 4 (BRD4) or, less frequently, with BRD3 (on chromosome 9), leading to the fusion genes BRD4–NUT or BRD3–NUT, respectively [1–3]. BRD is a DNA reader that activates transcription by binding to acetyl–modified lysine residues of histone tails [1, 3, 4]. The expression of several oncogenes, including transcription factors and MYC, is epigenetically regulated by BRD. More recently, a novel fusion gene between the methyl-transferase protein NSD3 on chromosome 8 and NUT has been reported (NSD3–NUT) [1, 5, 6]. NSD3 has shown to be associated with the extraterminal domains of BET proteins, which serves as a key component in the BRD–NUT oncogene complex . Moreover, two novel three–way translocations [t(9;15;19;q34;q13;p13.1), and t(4;15;19)(q13;q14;p13.1)] have been described [5, 6]. NUT rearrangement has been suggested to possibily represent a tumor–initiating event. Its importance in the pathogenesis of NUT midline carcinoma is further supported by the evidences that withdrawal of the NUT fusion protein resulted in a dramatic and irreversible squamous differentiation and growth arrest, thus demonstrating that the BRD–NUT protein blocks differentiation .
Alpha–fetoprotein elevation has been associated with chronic liver diseases and a limited number of cancers (hepatic primary tumors and metastases, bile duct, pancreatic, gastric and lung cancer, and non–seminoma germ–cell tumors). Moreover, in presence of testicular or mediastinal mass an elevated alpha–fetoprotein strongly suggests a non–seminoma germ–cell tumor especially in young patients.
Immunohistochemistry profile at the time of first evaluation
Clues to diagnosis (if positive)
Clues to diagnosis (if positive)
AE1-AE3 cytokeratin pool
Carcinomas, GCT (rare), thymoma, mesenchymal tumors
Lung, thyroid cancer
Non-seminoma GCT, HCC, pancreas carcinoma
Basal/squamous carcinoma, mesenchymal tumors, lymphomas, adenoid cystic carcinoma, salivary gland tumors, thymoma, thymic carcinoma, breast, urothelial carcinoma
Neuroendocrine neoplasms, adrenal gland carcinoma, mesenchymal tumors
Lymphomas (HL and NHL), non-seminoma GCT,
Hematologic malignances, mesenchymal tumors, papillary thyroid carcinoma, thymoma
Mesenchymal tumors, GCT, SCLC, leukemias, lymphomas, melanoma
adenocarcinoma, renal cell carcinoma, choriocarcinoma, mesenchymal tumors, mesothelioma, lymphoma, thymic carcinoma
Melanoma, mesenchymal tumors, adrenal cortical tumors, sex-cord stromal tumors
Lung cancer and other carcinomas, GCT (rare), mesenchymal tumors
Melanoma, mesenchymal tumors, adenoid cystic carcinoma, sex-cord stromal tumors
Lymphomas, NSCLC, mesenchymal tumors, RCC (rare)
Thymic carcinoma, thymomas, thyroid anaplastic carcinoma, RCC, neuroendocrine neoplasms, seminoma
Discussion and conclusions
Diagnosis of NUT midline carcinoma is quite challenging and demands to be hypothesized and specifically demonstrated. Indeed, microscopic features are quite unspecific and range from completely undifferentiated carcinoma to carcinoma with squamous differentiation and abrupt keratinization that may be either focal or prominent. Tumor cells usually have an epithelioid, medium–size appearance and are in general monomorphic with round to oval nuclei and distinct nucleoli. Further morphologic aspects are a high mitotic rate along with necrosis and neutrophilic infiltrates. Immunohistochemistry with the NUT antibody is positive with a diffuse nuclear staining. However, NUT positivity might be found in GCTs as well and, to be regarded as truly positive, it must be seen in >50% of tumor cells.
Another peculiarity of NUT midline carcinoma is represented by the relatively simple karyotype that often presents the NUT translocation as the only relevant abnormality. This strongly differentiate this tumor from other squamous cell carcinomas that usually harbor highly aberrant and complex karyotypes [9, 10].
Differential diagnosis includes several tumors, encompassing hematologic malignancies or neuroendocrine tumors, because of non–specific morphology and immunohistochemistry profile apart from the pathognomonic NUT protein expression and the characteristic cytogenetic abnormalities [1, 3, 11]. As a general rule, it is recommended to perform immunohistochemistry for NUT protein in all poorly differentiated carcinomas that lack glandular differentiation and whenever the clinical picture is not completely consistent with more frequent tumors (midline or unusual position, young people, no smoking habit, rapid progression upon therapy) [2, 8, 12]. Both clinical history and some pathologic features (i.e., monomorphic tumor cells with abrupt keratinization) might help in generating the suspicion of NUT midline carcinoma. [10–12].
Case reports of NUT midline carcinoma describing alpha–fetoprotein (AFP) elevation
Site(s) of disease
Serum AFP level
Zhu B et al.
Ball A et al.
Parikh SA et al.
Raza A et al.
Harada Y et al.
Mediastinum, lung, bone
Mediastinum, lymphnodes, bone
The observed elevation of alpha–fetoprotein in NUT midline carcinoma might be related to the suggested hypothesis that these cells arise from primitive neural crest–derived cells.  Indeed, both gene expression profile similar to adult ciliary ganglion  and the absence of the in-situ component are consistent with this cell of origin. .
Beyond its rarity, NUT midline carcinoma may initially and transiently respond to several cytotoxics  used to treat undifferentiated carcinomas, making even less likely the raising of the right diagnostic suspicion. Regardless the chosen treatment, activity was at most transient and short–lasting . Therefore, to reach the correct diagnosis in the shortest possible time is crucial because prognosis is dismal, clinical conditions may worsen in few days, conventional chemotherapy is only marginally active and, finally, a new target therapy based on bromodomain inhibitors is showing promising results [4, 19, 20]. Despite being an experimental treatment, patients should be strongly encouraged to enroll in clinical trials to rapidly explore these innovative therapeutic strategies.
In conclusion, to avoid misleading diagnostic interpretation in case of alpha–fetoprotein elevation, sharing patient information between pathologists and clinicians assessing patients affected by poorly differentiated carcinoma arising nearby midline structures is crucial and we point out to consider NUT midline carcinoma in the differential diagnosis. Finally, in light of our observation, we also suggest to measure alpha–fetoprotein levels during tumor treatment to monitor disease course.
Anaplastic lymphoma kinase
Human chorionic gonadotropin
Epithelial membrane antigen
Fluorescence in situ hybridization
Nuclear protein in testis
Placental alkaline phosphatase
Thyroid transcription factor-1
All authors wish to thank the patient and his family for their courage in fighting against this extremely aggressive disease. The authors also thank Joan C. Leonard for language editing.
This work was in part supported by the “Fondazione per la ricerca sui tumori dell’apparato muscoloscheletrico e rari Onlus” (CRT RF = 2016–0917 to G.G.) and by the “Associazione Italiana per la Ricerca sul Cancro” (IG 2015 Id.17226 to G.G.).
Study funders had no role in data collection and interpretation, writing of the report, nor the decision to submit for publication.
Availability of data and materials
The data that support the findings of this study are available from the corresponding author upon reasonable request.
LD, EP, FCS, MA, and GG took care of the patient; MM took care of the patient and required pathological consultations; GP and AF performed the pathological diagnosis; LD, GP, and GG wrote the manuscript on behalf of all authors; all authors approved the final version of the manuscript and agreed for publication. The corresponding author (GG) has final responsibility to submit for publication.
The authors declare that they have no competing interests.
Consent for publication
The authors obtained written informed consent from the patient to publish information on his disease and clinical course.
Ethics approval and consent to participate
Ethical approval is not applicable for this manuscript. The authors obtained patient’s written consent to participate.
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Open AccessThis article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.
- French CA, Rahman S, Walsh EM, Kühnle S, Grayson AR, Lemieux ME, Grunfeld N, Rubin BP, Antonescu CR, Zhang S, et al. NSD3-NUT fusion oncoprotein in NUT midline carcinoma: implications for a novel oncogenic mechanism. Cancer Discov. 2014;4(8):928–41.View ArticlePubMedPubMed CentralGoogle Scholar
- Bauer DE, Mitchell CM, Strait KM, Lathan CS, Stelow EB, Lüer SC, Muhammed S, Evans AG, Sholl LM, Rosai J, et al. Clinicopathologic features and long-term outcomes of NUT midline carcinoma. Clin Cancer Res. 2012;18(20):5773–9.View ArticlePubMedPubMed CentralGoogle Scholar
- French C. NUT midline carcinoma. Nat Rev Cancer. 2014;14(3):149–50.View ArticlePubMedGoogle Scholar
- Delmore JE, Issa GC, Lemieux ME, Rahl PB, Shi J, Jacobs HM, Kastritis E, Gilpatrick T, Paranal RM, Qi J, et al. BET bromodomain inhibition as a therapeutic strategy to target c-Myc. Cell. 2011;146(6):904–17.View ArticlePubMedPubMed CentralGoogle Scholar
- Mills AF, Lanfranchi M, Wein RO, Mukand-Cerro I, Pilichowska M, Cowan J, Bedi H. NUT midline carcinoma: a case report with a novel translocation and review of the literature. Head Neck Pathol. 2014;8(2):182–6.View ArticlePubMedGoogle Scholar
- Shatavi S, Fawole A, Haberichter K, Jaiyesimi I, French C. Nuclear protein in testis (NUT) midline carcinoma with a novel three-way translocation (4;15;19)(q13;q14;p13.1). Pathology. 2016;48(6):620–3.View ArticlePubMedGoogle Scholar
- French CA. Demystified molecular pathology of NUT midline carcinomas. J Clin Pathol. 2010;63(6):492–6.View ArticlePubMedGoogle Scholar
- Eble JN, Sauter G, Epstein JI, Sesterhenn IA. WHO classification of Tumours: pathology and genetics of Tumours of the urinary system and Male genital organs. Lyon: IARC Press; 2004.Google Scholar
- Haack H, Johnson LA, Fry CJ, Crosby K, Polakiewicz RD, Stelow EB, Hong SM, Schwartz BE, Cameron MJ, Rubin MA, et al. Diagnosis of NUT midline carcinoma using a NUT-specific monoclonal antibody. Am J Surg Pathol. 2009;33(7):984–91.View ArticlePubMedPubMed CentralGoogle Scholar
- French CA. The importance of diagnosing NUT midline carcinoma. Head Neck Pathol. 2013;7(1):11–6.View ArticlePubMedPubMed CentralGoogle Scholar
- Fang W, French CA, Cameron MJ, Han Y, Liu H. Clinicopathological significance of NUT rearrangements in poorly differentiated malignant tumors of the upper respiratory tract. Int J Surg Pathol. 2013;21(2):102–10.View ArticlePubMedGoogle Scholar
- Travis WD, Brambilla E, Burke AP, Marx A, Nicholson AG. WHO classification of Tumours of the lung, pleura, thymus and heart. Lyon: International Agency for Research on Cancer; 2015.Google Scholar
- Harada Y, Koyama T, Takeuchi K, Shoji K, Hoshi K, Oyama Y. NUT midline carcinoma mimicking a germ cell tumor: a case report. BMC Cancer. 2016;16(1):895.View ArticlePubMedPubMed CentralGoogle Scholar
- Ball A, Bromley A, Glaze S, French CA, Ghatage P, Köbel M. A rare case of NUT midline carcinoma. Gynecol Oncol Case Rep. 2012;3:1–3.View ArticlePubMedPubMed CentralGoogle Scholar
- Parikh SA, French CA, Costello BA, Marks RS, Dronca RS, Nerby CL, Roden AC, Peddareddigari VG, Hilton J, Shapiro GI, et al. NUT midline carcinoma: an aggressive intrathoracic neoplasm. J Thorac Oncol. 2013;8(10):1335–8.View ArticlePubMedGoogle Scholar
- Raza A, Cao H, Conrad R, Cobb C, Castelino-Prabhu S, Mirshahidi S, Shiraz P, Mirshahidi HR. Nuclear protein in testis midline carcinoma with unusual elevation of α-fetoprotein and synaptophysin positivity: a case report and review of the literature. Expert Rev Anticancer Ther. 2015;15(10):1199–213.View ArticlePubMedGoogle Scholar
- Zhu B, Laskin W, Chen Y, French CA, Cameron MJ, Nayar R, Lin X. NUT midline carcinoma: a neoplasm with diagnostic challenges in cytology. Cytopathology. 2011;22(6):414–7.View ArticlePubMedGoogle Scholar
- BioGPS, http://biogps.org/. Accessed 1 Feb 2017.
- Coudé MM, Braun T, Berrou J, Dupont M, Bertrand S, Masse A, Raffoux E, Itzykson R, Delord M, Riveiro ME, et al. BET inhibitor OTX015 targets BRD2 and BRD4 and decreases c-MYC in acute leukemia cells. Oncotarget. 2015;6(19):17698–712.View ArticlePubMedPubMed CentralGoogle Scholar
- Stathis A, Zucca E, Bekradda M, Gomez-Roca C, Delord JP, de La Motte RT, Uro-Coste E, de Braud F, Pelosi G, French CA. Clinical response of carcinomas harboring the BRD4-NUT Oncoprotein to the targeted Bromodomain inhibitor OTX015/MK-8628. Cancer Discov. 2016;6(5):492–500.View ArticlePubMedGoogle Scholar