Multimodal molecular analysis of an atypical small cell carcinoma of the ovary, hypercalcemic type

Cold Spring Harb Mol Case Stud. 2018 Oct 1;4(5):a002956. doi: 10.1101/mcs.a002956. Print 2018 Oct.

Abstract

A 12-yr-old normocalcemic female treated for a ruptured ovarian juvenile granulosa cell tumor at an outside hospital presented for exploratory laparotomy and gross surgical debulking of pelvic recurrence. Morphologically, the tumor was composed of sheets and nests of small blue cells forming cysts of various sizes and focal mucinous differentiation. Epithelial membrane antigen (EMA), patchy inhibin, and strong and diffuse p53 immunoreactivity were also observed. A revised diagnosis of mixed sex cord stromal tumor with heterologous elements was favored because of the inhibin immunoreactivity. Targeted next-generation sequencing of the tumor revealed a SMARCA4 c.1141C>T, p.Arg381Ter (NM_001128849.1) nonsense mutation and an in-frame 18-bp TP53 deletion (c.594_611del18, p.Gly199_Glu204del, NM_001126112.2). Cytogenetic analysis revealed a normal 46,XX karyotype, and OncoScan single-nucleotide polymorphism array analysis demonstrated copy-neutral loss of heterozygosity (CN-LOH) of 19p13.3-19p13.2 and mosaic CN-LOH of 17p13.3-p11.2 encompassing the SMARCA4 and TP53 loci, respectively. Subsequent germline SMARCA4 sequencing confirmed a heterozygous SMARCA4 p.Arg381Ter mutation. In lieu of the molecular findings, the diagnosis was amended to small cell carcinoma of the ovary, hypercalcemic type (SCCOHT). The patient was treated aggressively with paclitaxel, carboplatin, and bevacizumab. She received an autologous stem cell transplant but died 5 mo after SCCOHT diagnosis secondary to complications of the transplant. This case expands the morphologic, immunophenotypic, and genomic spectrum of SCCOHT and highlights how multimodal molecular analysis can assist with the diagnosis and clinical management of SCCOHT patients.

Keywords: ovarian neoplasm.

Publication types

  • Case Reports

MeSH terms

  • Biomarkers, Tumor / genetics
  • Carcinoma, Small Cell / classification
  • Carcinoma, Small Cell / diagnosis*
  • Carcinoma, Small Cell / genetics*
  • Child
  • Codon, Nonsense / genetics
  • DNA Helicases / genetics
  • Female
  • Granulosa Cell Tumor / pathology
  • Heterozygote
  • Humans
  • Hypercalcemia
  • Loss of Heterozygosity / genetics
  • Mutation / genetics
  • Neoplasm Recurrence, Local
  • Nuclear Proteins / genetics
  • Ovarian Neoplasms / diagnosis
  • Ovarian Neoplasms / genetics*
  • Ovarian Neoplasms / metabolism
  • Ovary / metabolism
  • Transcription Factors / genetics
  • Tumor Suppressor Protein p53 / genetics

Substances

  • Biomarkers, Tumor
  • Codon, Nonsense
  • Nuclear Proteins
  • TP53 protein, human
  • Transcription Factors
  • Tumor Suppressor Protein p53
  • SMARCA4 protein, human
  • DNA Helicases