| Literature DB >> 29588307 |
Jatinder Dhami1, Kim M Hirshfield1, Shridar Ganesan1, Mira Hellmann2, Veronica Rojas3, Judith K Amorosa4, Gregory M Riedlinger5, Hua Zhong5, Siraj M Ali6, Dean Pavlick6, Julia A Elvin6, Lorna Rodriguez-Rodriguez7.
Abstract
FGFR-TACC fusions, including FGFR3-TACC3, have been identified as potential oncogenic drivers and actionable alterations in a number of different cancer types. The clinical relevance of FGFR3-TACC3 fusions in endometrial cancer has not yet been described. Formalin-fixed, paraffin-embedded metastatic endometrial carcinoma from the spleen and peritoneum were sent for comprehensive genomic profiling (CGP) using the FoundationOne platform as part of a prospective tumor genomic profiling protocol. We report the identification of an FGFR3-TACC3 fusion in a case of metastatic endometrioid endometrial cancer. Other potentially actionable alterations detected in this specimen included PIK3CA T1025S and an uncharacterized rearrangement involving TSC2 The patient initially received an FGFR inhibitor as an investigational agent and experienced stable disease with complete resolution of a pelvic nodule; however, treatment had to be discontinued because of intolerable side effects. A PET/CT scan nearly 3 mo after discontinuation showed disease progression. She subsequently received the mTOR inhibitor, temsirolimus, later accompanied by letrozole, and achieved stable disease. Clinical benefit was attributed to the mTOR inhibitor as tumor stained negative for estrogen receptor. Temsirolimus was discontinued after >17 mo because of disease progression. FGFR inhibitors may have clinical benefit in the treatment of endometrial carcinoma with FGFR3-TACC3 fusions. Additionally, clinical benefit from an mTOR inhibitor may reflect a response to targeting the alteration in PIK3CA or TSC2 More research is needed to understand the activity of FGFR3-TACC3 fusions on tumors and to discover additional therapeutic options for endometrial carcinoma patients with this gene fusion.Entities:
Keywords: endometrial carcinoma
Mesh:
Substances:
Year: 2018 PMID: 29588307 PMCID: PMC5880253 DOI: 10.1101/mcs.a002089
Source DB: PubMed Journal: Cold Spring Harb Mol Case Stud ISSN: 2373-2873
Figure 1.Hematoxylin and eosin (H&E)-stained endometrial biopsy showing endometrial adenocarcinoma with papillary features and necrosis at low (A) and high (B) magnification, respectively.
Figure 2.H&E-stained slide of tissue from splenectomy showing metastatic, moderately differentiated adenocarcinoma with necrosis at low (A) and high (B) magnification, respectively.
Figure 3.H&E-stained slide showing metastatic adenocarcinoma with necrosis and calcifications following diagnostic laparoscopy with removal of the anterior abdominal wall nodule at low (A) and high (B) magnification, respectively; specimen from this procedure was sent for comprehensive genomic profiling.
Variants identified from comprehensive genomic profiling
| Gene | Chromosome | HGVS DNA reference | HGVS protein reference | Variant type | Predicted effect |
|---|---|---|---|---|---|
| 4 | t(4;4) | N/A | Fusion | Functional | |
| 3 | N/A | p.T1025S | Substitution | Predicted functional | |
| 16 | t(16;16) | N/A | Fusion | Unknown |
Targeted sequencing of the entire coding sequence was done for 236 genes and 47 introns of 19 genes involved in fusions at a depth of 500–1000× (median exon depth of 792×; 100% of the baited region was sequenced at a depth of at least 100×; sequence alignment error of only 0.27%). The depth of variant call reads was 59×; these 59 chimeric reads equate to an independently validated variant calling method described in Frampton et al. (2013). The depth of wild-type reads was 1155×.
HGVS, Human Genome Variation Society; N/A, not available.
Figure 4.CT scans of the abdomen and pelvis with contrast prior to initiation of an FGFR inhibitor on trial. (A) Axial CT image with oral and intravenous contrast at the level of the mid pelvis shows a 3-cm soft tissue mass with minimal calcifications (red arrow). (B) Coronal reconstructed CT image with oral and intravenous contrast through the anterior abdomen and pelvis shows the 3-cm soft tissue mass with minimal calcifications (red arrow). CT scans of the abdomen and pelvis with contrast obtained during treatment with FGFR inhibitor on trial. (C) Axial CT image with oral and intravenous contrast at the level of the mid pelvis shows no measurable mass. (D) Coronal reconstructed CT image with oral and intravenous contrast through the anterior abdomen and pelvis shows no measurable mass.
Figure 5.CT scans of the abdomen and pelvis with contrast shortly following discontinuation of trial with FGFR inhibitor. (A) Axial CT image shows no measurable mass. (B) Coronal reconstructed CT image shows no measurable mass. PET/CT scans 3 mo following cessation of the FGFR inhibitor on trial. (C) Axial CT image without oral or intravenous contrast at the mid pelvis shows a 3-cm mass with calcifications. (D) PET scan with coronal display shows an area of increased abnormal metabolic activity corresponding to the soft tissue mass (red arrow).
Figure 6.Diagram of the formation of the FGFR3-TACC3 fusion protein product.
Figure 7.Frequency of alterations found in FGFR3, PIK3CA, or TSC2 reported in uterine corpus endometrial carcinoma (TCGA Provisional) for 242 cases. The results shown here are based upon data generated by the TCGA Research Network: http://cancergenome.nih.gov/.
Figure 8.Percentages of uterine cancer cases with alterations in FGFR genes, as reported by TCGA for 242 cases (TCGA Provisional). The results shown here are based upon data generated by the TCGA Research Network: http://cancergenome.nih.gov/.
Descriptions of the genomic breakpoints for the patients provided by Foundation Medicine, Inc.
| Disease ontologya | Genomic breakpoints |
|---|---|
| Uterus endometrial adenocarcinoma (NOS) | Chr 4 duplication fragment: 5′- |
| aUterus endometrial adenocarcinoma (NOS) | Chr 4 duplication fragment: 5′- |
| Uterus endometrial adenocarcinoma clear cell | Chr 4 duplication fragment: 5′- |
| Uterus endometrial adenocarcinoma papillary serous | Chr 4 duplication fragment: 5′- |
aHighlighted case results.