- Email: [email protected]
NUT Midline Carcinoma: An Aggressive Intrathoracic Neoplasm
BRIEF REPORT
NUT Midline Carcinoma An Aggressive Intrathoracic Neoplasm Sameer A. Parikh, MD,* Christopher A. French, MD,† Brian A. Costello,MD,* Randolph S. Marks, MD,* Roxana S. Dronca, MD,* Craig L. Nerby, MD,‡ Anja C. Roden, MD,‡ Vijay G. Peddareddigari, MD,§ John Hilton, MD,║ Geoffrey I. Shapiro, MD,║ and Julian R. Molina, MD, PhD*
uclear protein in testis (NUT) midline carcinoma (NMC) is a N poorly differentiated squamous cell carcinoma that is characterized by a balanced translocation between chromosomes 15 and 19 [t(15;19)(q14;p13.1)]. This genetic aberration results in the fusion of the NUT gene on chromosome 15 to the bromodomain containing 4 (BRD4) gene on chromosome 19. The resultant BRD4-NUT fusion oncogene leads to global hypoacetylation and transcriptional repression of genes required for differentiation.” Although it was first reported in 1991 by Kubonishi et al., awareness of this condition remains low and the diagnosis is overlooked initially in a number of patients. A 36-year-old man complained of cough and right-sided chest pain for 3 weeks before presentation. Imaging studies revealed a right hilar mass, and a bronchoscopic biopsy was consistent with an aggressive poorly differentiated neoplasm. A combination of cisplatin, ifosfamide, and etoposide was administered for two cycles without any improvement. A repeat core biopsy showed focal squamous differentiation; and given the clinical presentation along with the histologic features, NMC was considered in the differential diagnosis. Immunohistochemical staining for NUT was positive, and dual-color break-apart fluorescence in situ hybridization demonstrated BRD4NUT rearrangement, thereby confirming a diagnosis of NMC. Our patient was subsequently enrolled on a phase 1 clinical trial of a novel, orally bioavailable bromodomain and extra terminal inhibitor, GSK525762 (NCT01587703). This report illustrates the challenges in diagnosing this rare malignancy, and highlights new treatment options for these patients.
*Department of Oncology, Mayo Clinic, Rochester, Minnesota; †Department of Pathology, Brigham and Women’s Hospital, Boston, Massachusetts; ‡Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota; §GlaxoSmithKline, Philadelphia, Pennsylvania; and ║Early Drug Development Center, Dana Farber Cancer Institute, Boston, Massachusetts. Address for correspondence: Sameer A. Parikh, MD, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905. E-mail: [email protected] Presented at the 13th Annual Targeted Therapies of Lung Cancer Meeting, Santa Monica, California, February 2013. Disclosure: Dr. Costello is a member of the Data Safety and Monitoring Board for a phase 1 trial sponsored by Synergene Therapeutics and has received financial support for the same. Dr. Peddareddigari is currently employed by GlaxoSmithKline and owns stock in the company. The other authors declare no conflict of interest. Copyright © 2013 by the International Association for the Study of Lung Cancer ISSN: 1556-0864/13/0810-1335
Key Words: Poorly differentiated neoplasm, bromodomain containing 4 nuclear protein in testis, Epigenetics, Bromodomain and extra terminal inhibitor, Histone deacetylase inhibitors. (J Thorac Oncol. 2013;8: 1335-1338)
A
36-year-old white man, with no significant medical history, sought medical attention because of a 10-day history of cough and right-sided chest pain. He had never smoked cigarettes or used illicit drugs. His physical examination was remarkable for a temperature of 39°C and rales in the right lower chest. He received oral antimicrobial therapy for presumed community-acquired pneumonia. After his symptoms did not resolve, a chest radiograph was performed 3 weeks later, demonstrating a mass in the right hilar area. A computed tomography scan of the chest revealed subcarinal and right supraclavicular lymphadenopathy, along with a conglomerate mass measuring 6 × 6cm in the right hilar area (Fig. 1A). A transbronchial core biopsy of the right hilar mass showed a poorly differentiated neoplasm comprising of large epithelioid cells with a small amount of cytoplasm, prominent nucleoli, and extensive necrosis (Fig. 1B). Immunostains were negative for keratins (AE1/ AE3, CK7, OSCAR, CAM 5.2), epithelial membrane antigen (EMA), CD45, S100, CD117, thyroid transcription factor 1, placental alkaline phosphatase, octamer-binding transcription factor 4, and vascular markers (CD31, CD34, friend leukemia integration-1 transcription factor 1). A testicular ultrasound was unremarkable and serum alfa-fetoprotein level was elevated (62 ng/ml, normal <6 ng/ml). A clinical diagnosis of nonseminomatous primary mediastinal germ cell tumor was made, and the patient was started on combination chemotherapy consisting of etoposide, ifosfamide, and cisplatin. A computed tomography scan of the chest performed after two cycles of therapy showed marked worsening of intrathoracic lymphadenopathy and the right hilar mass (Fig. 2A). Mediastinoscopy-directed biopsy of the right paratracheal lymphadenopathy demonstrated neoplastic epithelioid cells with cytologic features similar to the previous biopsy (Fig. 2B). The neoplastic cells focally expressed keratin AE1/ AE3 (Fig. 2C), OSCAR, CAM 5.2, CD138, thyroid transcription factor 1, and CD56. Immunostain for anaplastic lymphoma kinase was negative, and epidermal growth factor receptor sequencing demonstrated a wild-type gene. Given
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Journal of Thoracic Oncology • Volume 8, Number 10, October 2013
Figure 1. A, Computed tomography scan of the chest showing a 6 × 6cm mass in the right hilar area and an enlarged subcarinal lymph node. B, Pictorial depiction of the typical breakpoint in NUT midline carcinoma. NUT is present on 15q14 and BRD4 (bromodomain containing 4) on 19p13.1. Scattered neoplastic cells with large hyperchromatic nuclei, prominent nucleoli, and scant cytoplasm in a background of extensive necrosis (cell-block preparation, hematoxylin and eosin 40×).
the clinical presentation together with the histopathologic features, nuclear protein in testis (NUT) midline carcinoma (NMC) was considered. An immunostain for NUT was positive (Fig. 3A), and dual-color break-apart fluorescence in situ hybridization (FISH) demonstrated bromodomain containing 4 (BRD4)-NUT rearrangement, consistent with a diagnosis of NMC (Fig. 3B). The patient received 2000 cGy of radiation therapy to the right thorax, and was subsequently enrolled on the first dose level of a recently activated phase 1 clinical trial of a novel, orally bioavailable bromodomain and extra terminal (BET) inhibitor GSK525762 (NCT01587703).1 By protocol design of staggered dosing, the patient received a lead-in dose, which was followed 1 week later by additional doses. Unfortunately, by the second week of the protocol, his disease had progressed rapidly, requiring chest tube drainage of a large right serosanguineous pleural effusion, and he died before continuous daily dosing could be implemented. An autopsy was performed, which confirmed the diagnosis of NMC. The postmortem examination was remarkable for massive hilar lymphadenopathy with extension of tumor to the surfaces of the mediastinum, pleura, pulmonary hila, right and left lung, trachea, thoracic aorta, diaphragm and subcutaneous fat, with extrinsic compression and invasion of both airways and
vasculature. NMC cells were used for the generation of a cell line that has proved useful for both in vitro and in vivo studies.
DISCUSSION NMC is a rare, aggressive, and almost uniformly fatal, genetically defined subtype of squamous cell carcinoma. In contrast to most squamous cell carcinomas that have a complex karyotype, NMC is characterized by the presence of a single reciprocal translocation, t(15;19)(q14;p13.1). This genetic aberration usually results in the fusion of the NUT gene on chromosome 15q14 to the BET family gene BRD4 on chromosome 19p13.1.2 In a minority of cases, NUT is fused to the close homologue of BRD4, BRD3, or a gene of unknown identity.3 The true incidence of NMC is unknown. Although it was initially recognized as occurring almost exclusively in young children, recent literature suggests a broad range of age presentation, including individuals older than 60 years.4 Risk factors for the development of this malignancy remain unknown. Given the early age at onset and the observation that most patients reported with this tumor are nonsmokers, it seems that smoking does not play a pathogenic role. In addition, Epstein-Barr virus and human papilloma virus have not
Figure 2. A, Computed tomography scan of the chest 2 months later showing an increase in the size of the right hilar mass and the subcarinal lymph node. B, Repeat biopsy 2 months later showing sheets of large neoplastic cells with vesicular chromatin and prominent nucleoli. Individual tumor cell necrosis and apoptosis is also seen (hematoxylin and eosin 40×). C, The neoplastic cells focally express keratin.
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Copyright © 2013 by the International Association for the Study of Lung Cancer
Journal of Thoracic Oncology • Volume 8, Number 10, October 2013
NUT Midline Carcinoma
FIGURE 3. A, Nuclear protein in testis immunostain demonstrating a speckled pattern. B, FISH demonstrating BRD4-NUT translocation. Shown is dual color bring-together FISH on tumor cell nuclei using red and green probes covering BRD4 and NUT genes, respectively. Nuclei with red-green doublets demonstrate fusion of BRD4 and NUT. The nucleus with two red and two green signals represent nontumor nuclei containing two normal alleles each of BRD4 and NUT. FISH, fluorescent in situ hybridization; BRD4, ; NUT, nuclear protein in testis.
been detected in NMC tumors.5,6 NMC typically arises from midline anatomic sites, most commonly the upper aerodigestive tract and the mediastinum. However, other sites of origin such as the parotid gland, pancreas, and iliac bone have also been reported.7–9 The pathologic findings of NMC are generally consistent with a poorly differentiated carcinoma with focal squamous differentiation. In a retrospective review of 98 poorly differentiated carcinomas in children and young adults, 11 patients (11%) had NUT gene rearrangements by dual-color FISH.3 NUT rearrangement at other sites has an incidence of: three in 151 primary sinonasal carcinomas (2%),10 one in 148 poorly differentiated thymic tumors (0.7%),11 and five in 28 poorly differentiated carcinomas of the upper aerodigestive tract (18%).5 A diagnosis of NMC can be confirmed by karyotype analysis that shows t(15:19); however, most squamous cell cancers are not submitted for karyotypic analysis. The use of FISH technique that uses dual-color, break-apart bacterial artificial chromosome probes flanking the NUT and BRD4 loci has led to improved accuracy in diagnosis. However, the development of an immunohistochemical stain for NUT expression has 100% specificity and 87% sensitivity in detection of NUT rearrangement outside of the testis, and is considered the first-line approach to diagnosis of NMC.12 The vast majority of patients with NMC are treated with multimodal therapy including surgery, radiation therapy, and chemotherapy. Unfortunately, the outcome of most patients with NMC remains dismal, with a median overall survival of only 6.7 months.4 A wide array of chemotherapeutic agents have been tried—including the use of doxorubicin-based regimens—unfortunately, they are not associated with improved outcomes. In the largest reported retrospective analysis of 63 patients with NMC, early radiation therapy and extent of surgery were the only predictors of improved survival. No chemotherapy regimen was shown to improve survival.4 Although there have been some reports of patients with NUT-variant NMCs having a longer survival,3 this large analysis failed to show such an association.
Recent experiments have shed light on the role of epigenetics in the pathogenesis of this disease. Evidence suggests a model whereby the BRD4-NUT fusion oncoprotein binds to and activates p300, a histone acetyltransferase, and sequesters its activity to localized regions of BRD4-NUT–acetylchromatin binding. This leads to a relative paucity of histone deacetylase activity elsewhere, and thereby leads to global hypoacetylation and inadequate expression of genes required for differentiation. Indeed, therapy with histone deacetylase inhibitors (HDACi), which restores chromatin acetylation, has been shown to induce terminal differentiation of NMC cells in vitro.13 Targeting the BRD4-NUT complex with small-molecule BET inhibitors (BETi), which are acetyl-histone mimetics that competitively inhibit bromodomain-acetyl-histone binding, have also been shown to induce squamous differentiation of NMC cells.14 One of the members of this class, GSK525762, is being tested in a phase 1 clinical trial.1 This trial is in the early stages of dose escalation and is actively recruiting subjects; however, a discussion regarding its efficacy as a single agent is not possible at this time. As is the case with other targeted therapies, it is possible that combination therapy with HDACi and BETi will likely be more effective than monotherapy for this aggressive disease. The rapid disease progression that occurred in the patient presented here illustrates the difficulty in evaluating novel agents for this disease and emphasizes the need for clinical trial designs that minimize washout periods from prior treatment, and use pharmacodynamically effective doses as quickly as possible. In summary, NMC remains an underrecognized aggressive neoplasm that should be considered in the differential diagnosis of poorly differentiated carcinoma without glandular differentiation, involving any organ, without known causes such as human papilloma virus or Epstein-Barr virus. The recent commercial availability of an immunohistochemical test against the NUT protein will make it easier for pathologists to diagnose NMC, once it is clinically suspected. Our case report highlights the importance of repeating a core biopsy if patients do not respond to chemotherapy directed
Copyright © 2013 by the International Association for the Study of Lung Cancer
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Parikh et al.
toward an initial diagnosis. In addition, fostering an international collaboration to enroll patients in a timely fashion on clinical trials that target the BRD4-NUT fusion oncogene will be critical in improving outcomes of NMC patients.
ACKNOWLEDGMENTS
The patient relocated from Minnesota to Massachusetts for participation in the clinical trial. We are deeply indebted to him and his family for their participation and contribution to NUT midline carcinoma research. We thank Andrew Wolanski, Aya Sato-DiLorenzo and Ketki Bhushan for assistance with his care and Laurel Adams of Glaxo Smith Kline for guidance during the course of the clinical trial. We would also like to acknowledge Glaxo Smith Kline Oncology and Glaxo Smith Kline EpiNova for providing GSK525762 compound for use in the phase 1 clinical trial. REFERENCES 1. Available at clinicaltrials.gov; searchterm: NUT midline carcinoma. Accessed January 20, 2013. 2. French CA. Pathogenesis of NUT midline carcinoma. Annu Rev Pathol 2012;7:247–265. 3. French CA, Kutok JL, Faquin WC, et al. Midline carcinoma of children and young adults with NUT rearrangement. J Clin Oncol 2004;22:4135–4139.
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4. Bauer DE, Mitchell CM, Strait KM, et al. Clinicopathologic features and long-term outcomes of NUT midline carcinoma. Clin Cancer Res 2012;18:5773–5779. 5. Stelow EB, Bellizzi AM, Taneja K, et al. NUT rearrangement in undifferentiated carcinomas of the upper aerodigestive tract. Am J Surg Pathol 2008;32:828–834. 6. French CA, Miyoshi I, Aster JC, et al. BRD4 bromodomain gene rearrangement in aggressive carcinoma with translocation t(15;19). Am J Pathol 2001;159:1987–1992. 7. Mertens F, Wiebe T, Adlercreutz C, Mandahl N, French CA. Successful treatment of a child with t(15;19)-positive tumor. Pediatr Blood Cancer 2007;49:1015–1017. 8. Ziai J, French CA, Zambrano E. NUT gene rearrangement in a poorlydifferentiated carcinoma of the submandibular gland. Head Neck Pathol 2010;4:163–168. 9. Shehata BM, Steelman CK, Abramowsky CR, et al. NUT midline carcinoma in a newborn with multiorgan disseminated tumor and a 2-year-old with a pancreatic/hepatic primary. Pediatr Dev Pathol 2010;13:481–485. 10. Bishop JA, Westra WH: NUT midline carcinomas of the sinonasal tract. Am J Surg Pathol 36:1216–21, 2012 11. Petrini P, French CA, Rajan A, et al. NUT rearrangement is uncommon in human thymic epithelial tumors. J Thorac Oncol 2012;7:744–750. 12. Haack H, Johnson LA, Fry CJ, et al. Diagnosis of NUT midline carcinoma using a NUT-specific monoclonal antibody. Am J Surg Pathol 2009;33:984–991. 13. Schwartz BE, Hofer MD, Lemieux ME, et al. Differentiation of NUT midline carcinoma by epigenomic reprogramming. Cancer Res 2011;71:2686–2696. 14. Filippakopoulos P, Qi J, Picaud S, et al. Selective inhibition of BET bromodomains. Nature 2010;468:1067–1073.
Copyright © 2013 by the International Association for the Study of Lung Cancer
NUT Midline Carcinoma An Aggressive Intrathoracic Neoplasm Sameer A. Parikh, MD,* Christopher A. French, MD,† Brian A. Costello,MD,* Randolph S. Marks, MD,* Roxana S. Dronca, MD,* Craig L. Nerby, MD,‡ Anja C. Roden, MD,‡ Vijay G. Peddareddigari, MD,§ John Hilton, MD,║ Geoffrey I. Shapiro, MD,║ and Julian R. Molina, MD, PhD*
uclear protein in testis (NUT) midline carcinoma (NMC) is a N poorly differentiated squamous cell carcinoma that is characterized by a balanced translocation between chromosomes 15 and 19 [t(15;19)(q14;p13.1)]. This genetic aberration results in the fusion of the NUT gene on chromosome 15 to the bromodomain containing 4 (BRD4) gene on chromosome 19. The resultant BRD4-NUT fusion oncogene leads to global hypoacetylation and transcriptional repression of genes required for differentiation.” Although it was first reported in 1991 by Kubonishi et al., awareness of this condition remains low and the diagnosis is overlooked initially in a number of patients. A 36-year-old man complained of cough and right-sided chest pain for 3 weeks before presentation. Imaging studies revealed a right hilar mass, and a bronchoscopic biopsy was consistent with an aggressive poorly differentiated neoplasm. A combination of cisplatin, ifosfamide, and etoposide was administered for two cycles without any improvement. A repeat core biopsy showed focal squamous differentiation; and given the clinical presentation along with the histologic features, NMC was considered in the differential diagnosis. Immunohistochemical staining for NUT was positive, and dual-color break-apart fluorescence in situ hybridization demonstrated BRD4NUT rearrangement, thereby confirming a diagnosis of NMC. Our patient was subsequently enrolled on a phase 1 clinical trial of a novel, orally bioavailable bromodomain and extra terminal inhibitor, GSK525762 (NCT01587703). This report illustrates the challenges in diagnosing this rare malignancy, and highlights new treatment options for these patients.
*Department of Oncology, Mayo Clinic, Rochester, Minnesota; †Department of Pathology, Brigham and Women’s Hospital, Boston, Massachusetts; ‡Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota; §GlaxoSmithKline, Philadelphia, Pennsylvania; and ║Early Drug Development Center, Dana Farber Cancer Institute, Boston, Massachusetts. Address for correspondence: Sameer A. Parikh, MD, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905. E-mail: [email protected] Presented at the 13th Annual Targeted Therapies of Lung Cancer Meeting, Santa Monica, California, February 2013. Disclosure: Dr. Costello is a member of the Data Safety and Monitoring Board for a phase 1 trial sponsored by Synergene Therapeutics and has received financial support for the same. Dr. Peddareddigari is currently employed by GlaxoSmithKline and owns stock in the company. The other authors declare no conflict of interest. Copyright © 2013 by the International Association for the Study of Lung Cancer ISSN: 1556-0864/13/0810-1335
Key Words: Poorly differentiated neoplasm, bromodomain containing 4 nuclear protein in testis, Epigenetics, Bromodomain and extra terminal inhibitor, Histone deacetylase inhibitors. (J Thorac Oncol. 2013;8: 1335-1338)
A
36-year-old white man, with no significant medical history, sought medical attention because of a 10-day history of cough and right-sided chest pain. He had never smoked cigarettes or used illicit drugs. His physical examination was remarkable for a temperature of 39°C and rales in the right lower chest. He received oral antimicrobial therapy for presumed community-acquired pneumonia. After his symptoms did not resolve, a chest radiograph was performed 3 weeks later, demonstrating a mass in the right hilar area. A computed tomography scan of the chest revealed subcarinal and right supraclavicular lymphadenopathy, along with a conglomerate mass measuring 6 × 6cm in the right hilar area (Fig. 1A). A transbronchial core biopsy of the right hilar mass showed a poorly differentiated neoplasm comprising of large epithelioid cells with a small amount of cytoplasm, prominent nucleoli, and extensive necrosis (Fig. 1B). Immunostains were negative for keratins (AE1/ AE3, CK7, OSCAR, CAM 5.2), epithelial membrane antigen (EMA), CD45, S100, CD117, thyroid transcription factor 1, placental alkaline phosphatase, octamer-binding transcription factor 4, and vascular markers (CD31, CD34, friend leukemia integration-1 transcription factor 1). A testicular ultrasound was unremarkable and serum alfa-fetoprotein level was elevated (62 ng/ml, normal <6 ng/ml). A clinical diagnosis of nonseminomatous primary mediastinal germ cell tumor was made, and the patient was started on combination chemotherapy consisting of etoposide, ifosfamide, and cisplatin. A computed tomography scan of the chest performed after two cycles of therapy showed marked worsening of intrathoracic lymphadenopathy and the right hilar mass (Fig. 2A). Mediastinoscopy-directed biopsy of the right paratracheal lymphadenopathy demonstrated neoplastic epithelioid cells with cytologic features similar to the previous biopsy (Fig. 2B). The neoplastic cells focally expressed keratin AE1/ AE3 (Fig. 2C), OSCAR, CAM 5.2, CD138, thyroid transcription factor 1, and CD56. Immunostain for anaplastic lymphoma kinase was negative, and epidermal growth factor receptor sequencing demonstrated a wild-type gene. Given
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Parikh et al.
Journal of Thoracic Oncology • Volume 8, Number 10, October 2013
Figure 1. A, Computed tomography scan of the chest showing a 6 × 6cm mass in the right hilar area and an enlarged subcarinal lymph node. B, Pictorial depiction of the typical breakpoint in NUT midline carcinoma. NUT is present on 15q14 and BRD4 (bromodomain containing 4) on 19p13.1. Scattered neoplastic cells with large hyperchromatic nuclei, prominent nucleoli, and scant cytoplasm in a background of extensive necrosis (cell-block preparation, hematoxylin and eosin 40×).
the clinical presentation together with the histopathologic features, nuclear protein in testis (NUT) midline carcinoma (NMC) was considered. An immunostain for NUT was positive (Fig. 3A), and dual-color break-apart fluorescence in situ hybridization (FISH) demonstrated bromodomain containing 4 (BRD4)-NUT rearrangement, consistent with a diagnosis of NMC (Fig. 3B). The patient received 2000 cGy of radiation therapy to the right thorax, and was subsequently enrolled on the first dose level of a recently activated phase 1 clinical trial of a novel, orally bioavailable bromodomain and extra terminal (BET) inhibitor GSK525762 (NCT01587703).1 By protocol design of staggered dosing, the patient received a lead-in dose, which was followed 1 week later by additional doses. Unfortunately, by the second week of the protocol, his disease had progressed rapidly, requiring chest tube drainage of a large right serosanguineous pleural effusion, and he died before continuous daily dosing could be implemented. An autopsy was performed, which confirmed the diagnosis of NMC. The postmortem examination was remarkable for massive hilar lymphadenopathy with extension of tumor to the surfaces of the mediastinum, pleura, pulmonary hila, right and left lung, trachea, thoracic aorta, diaphragm and subcutaneous fat, with extrinsic compression and invasion of both airways and
vasculature. NMC cells were used for the generation of a cell line that has proved useful for both in vitro and in vivo studies.
DISCUSSION NMC is a rare, aggressive, and almost uniformly fatal, genetically defined subtype of squamous cell carcinoma. In contrast to most squamous cell carcinomas that have a complex karyotype, NMC is characterized by the presence of a single reciprocal translocation, t(15;19)(q14;p13.1). This genetic aberration usually results in the fusion of the NUT gene on chromosome 15q14 to the BET family gene BRD4 on chromosome 19p13.1.2 In a minority of cases, NUT is fused to the close homologue of BRD4, BRD3, or a gene of unknown identity.3 The true incidence of NMC is unknown. Although it was initially recognized as occurring almost exclusively in young children, recent literature suggests a broad range of age presentation, including individuals older than 60 years.4 Risk factors for the development of this malignancy remain unknown. Given the early age at onset and the observation that most patients reported with this tumor are nonsmokers, it seems that smoking does not play a pathogenic role. In addition, Epstein-Barr virus and human papilloma virus have not
Figure 2. A, Computed tomography scan of the chest 2 months later showing an increase in the size of the right hilar mass and the subcarinal lymph node. B, Repeat biopsy 2 months later showing sheets of large neoplastic cells with vesicular chromatin and prominent nucleoli. Individual tumor cell necrosis and apoptosis is also seen (hematoxylin and eosin 40×). C, The neoplastic cells focally express keratin.
1336
Copyright © 2013 by the International Association for the Study of Lung Cancer
Journal of Thoracic Oncology • Volume 8, Number 10, October 2013
NUT Midline Carcinoma
FIGURE 3. A, Nuclear protein in testis immunostain demonstrating a speckled pattern. B, FISH demonstrating BRD4-NUT translocation. Shown is dual color bring-together FISH on tumor cell nuclei using red and green probes covering BRD4 and NUT genes, respectively. Nuclei with red-green doublets demonstrate fusion of BRD4 and NUT. The nucleus with two red and two green signals represent nontumor nuclei containing two normal alleles each of BRD4 and NUT. FISH, fluorescent in situ hybridization; BRD4, ; NUT, nuclear protein in testis.
been detected in NMC tumors.5,6 NMC typically arises from midline anatomic sites, most commonly the upper aerodigestive tract and the mediastinum. However, other sites of origin such as the parotid gland, pancreas, and iliac bone have also been reported.7–9 The pathologic findings of NMC are generally consistent with a poorly differentiated carcinoma with focal squamous differentiation. In a retrospective review of 98 poorly differentiated carcinomas in children and young adults, 11 patients (11%) had NUT gene rearrangements by dual-color FISH.3 NUT rearrangement at other sites has an incidence of: three in 151 primary sinonasal carcinomas (2%),10 one in 148 poorly differentiated thymic tumors (0.7%),11 and five in 28 poorly differentiated carcinomas of the upper aerodigestive tract (18%).5 A diagnosis of NMC can be confirmed by karyotype analysis that shows t(15:19); however, most squamous cell cancers are not submitted for karyotypic analysis. The use of FISH technique that uses dual-color, break-apart bacterial artificial chromosome probes flanking the NUT and BRD4 loci has led to improved accuracy in diagnosis. However, the development of an immunohistochemical stain for NUT expression has 100% specificity and 87% sensitivity in detection of NUT rearrangement outside of the testis, and is considered the first-line approach to diagnosis of NMC.12 The vast majority of patients with NMC are treated with multimodal therapy including surgery, radiation therapy, and chemotherapy. Unfortunately, the outcome of most patients with NMC remains dismal, with a median overall survival of only 6.7 months.4 A wide array of chemotherapeutic agents have been tried—including the use of doxorubicin-based regimens—unfortunately, they are not associated with improved outcomes. In the largest reported retrospective analysis of 63 patients with NMC, early radiation therapy and extent of surgery were the only predictors of improved survival. No chemotherapy regimen was shown to improve survival.4 Although there have been some reports of patients with NUT-variant NMCs having a longer survival,3 this large analysis failed to show such an association.
Recent experiments have shed light on the role of epigenetics in the pathogenesis of this disease. Evidence suggests a model whereby the BRD4-NUT fusion oncoprotein binds to and activates p300, a histone acetyltransferase, and sequesters its activity to localized regions of BRD4-NUT–acetylchromatin binding. This leads to a relative paucity of histone deacetylase activity elsewhere, and thereby leads to global hypoacetylation and inadequate expression of genes required for differentiation. Indeed, therapy with histone deacetylase inhibitors (HDACi), which restores chromatin acetylation, has been shown to induce terminal differentiation of NMC cells in vitro.13 Targeting the BRD4-NUT complex with small-molecule BET inhibitors (BETi), which are acetyl-histone mimetics that competitively inhibit bromodomain-acetyl-histone binding, have also been shown to induce squamous differentiation of NMC cells.14 One of the members of this class, GSK525762, is being tested in a phase 1 clinical trial.1 This trial is in the early stages of dose escalation and is actively recruiting subjects; however, a discussion regarding its efficacy as a single agent is not possible at this time. As is the case with other targeted therapies, it is possible that combination therapy with HDACi and BETi will likely be more effective than monotherapy for this aggressive disease. The rapid disease progression that occurred in the patient presented here illustrates the difficulty in evaluating novel agents for this disease and emphasizes the need for clinical trial designs that minimize washout periods from prior treatment, and use pharmacodynamically effective doses as quickly as possible. In summary, NMC remains an underrecognized aggressive neoplasm that should be considered in the differential diagnosis of poorly differentiated carcinoma without glandular differentiation, involving any organ, without known causes such as human papilloma virus or Epstein-Barr virus. The recent commercial availability of an immunohistochemical test against the NUT protein will make it easier for pathologists to diagnose NMC, once it is clinically suspected. Our case report highlights the importance of repeating a core biopsy if patients do not respond to chemotherapy directed
Copyright © 2013 by the International Association for the Study of Lung Cancer
1337
Journal of Thoracic Oncology • Volume 8, Number 10, October 2013
Parikh et al.
toward an initial diagnosis. In addition, fostering an international collaboration to enroll patients in a timely fashion on clinical trials that target the BRD4-NUT fusion oncogene will be critical in improving outcomes of NMC patients.
ACKNOWLEDGMENTS
The patient relocated from Minnesota to Massachusetts for participation in the clinical trial. We are deeply indebted to him and his family for their participation and contribution to NUT midline carcinoma research. We thank Andrew Wolanski, Aya Sato-DiLorenzo and Ketki Bhushan for assistance with his care and Laurel Adams of Glaxo Smith Kline for guidance during the course of the clinical trial. We would also like to acknowledge Glaxo Smith Kline Oncology and Glaxo Smith Kline EpiNova for providing GSK525762 compound for use in the phase 1 clinical trial. REFERENCES 1. Available at clinicaltrials.gov; searchterm: NUT midline carcinoma. Accessed January 20, 2013. 2. French CA. Pathogenesis of NUT midline carcinoma. Annu Rev Pathol 2012;7:247–265. 3. French CA, Kutok JL, Faquin WC, et al. Midline carcinoma of children and young adults with NUT rearrangement. J Clin Oncol 2004;22:4135–4139.
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4. Bauer DE, Mitchell CM, Strait KM, et al. Clinicopathologic features and long-term outcomes of NUT midline carcinoma. Clin Cancer Res 2012;18:5773–5779. 5. Stelow EB, Bellizzi AM, Taneja K, et al. NUT rearrangement in undifferentiated carcinomas of the upper aerodigestive tract. Am J Surg Pathol 2008;32:828–834. 6. French CA, Miyoshi I, Aster JC, et al. BRD4 bromodomain gene rearrangement in aggressive carcinoma with translocation t(15;19). Am J Pathol 2001;159:1987–1992. 7. Mertens F, Wiebe T, Adlercreutz C, Mandahl N, French CA. Successful treatment of a child with t(15;19)-positive tumor. Pediatr Blood Cancer 2007;49:1015–1017. 8. Ziai J, French CA, Zambrano E. NUT gene rearrangement in a poorlydifferentiated carcinoma of the submandibular gland. Head Neck Pathol 2010;4:163–168. 9. Shehata BM, Steelman CK, Abramowsky CR, et al. NUT midline carcinoma in a newborn with multiorgan disseminated tumor and a 2-year-old with a pancreatic/hepatic primary. Pediatr Dev Pathol 2010;13:481–485. 10. Bishop JA, Westra WH: NUT midline carcinomas of the sinonasal tract. Am J Surg Pathol 36:1216–21, 2012 11. Petrini P, French CA, Rajan A, et al. NUT rearrangement is uncommon in human thymic epithelial tumors. J Thorac Oncol 2012;7:744–750. 12. Haack H, Johnson LA, Fry CJ, et al. Diagnosis of NUT midline carcinoma using a NUT-specific monoclonal antibody. Am J Surg Pathol 2009;33:984–991. 13. Schwartz BE, Hofer MD, Lemieux ME, et al. Differentiation of NUT midline carcinoma by epigenomic reprogramming. Cancer Res 2011;71:2686–2696. 14. Filippakopoulos P, Qi J, Picaud S, et al. Selective inhibition of BET bromodomains. Nature 2010;468:1067–1073.
Copyright © 2013 by the International Association for the Study of Lung Cancer