Clinical utility of Todai OncoPanel in the setting of approved comprehensive cancer genomic profiling tests in Japan.

Comprehensive cancer genome profiling (CGP) has been nationally reimbursed in Japan since June 2019. Less than 10% of the patients have been reported to undergo recommended treatment. Todai OncoPanel (TOP) is a dual DNA-RNA panel as well as a paired tumor-normal matched test. Two hundred patients underwent TOP as part of Advanced Medical Care B with approval from the Ministry of Health, Labour and Welfare between September 2018 and December 2019. Tests were carried out in patients with cancers without standard treatment or when patients had already undergone standard treatment. Data from DNA and RNA panels were analyzed in 198 and 191 patients, respectively. The percentage of patients who were given therapeutic or diagnostic recommendations was 61% (120/198). One hundred and four samples (53%) harbored gene alterations that were detected with the DNA panel and had potential treatment implications, and 14 samples (7%) had a high tumor mutational burden. Twenty-two samples (11.1%) harbored 30 fusion transcripts or MET exon 14 skipping that were detected by the RNA panel. Of those 30 transcripts, 6 had treatment implications and 4 had diagnostic implications. Thirteen patients (7%) were found to have pathogenic or likely pathogenic germline variants and genetic counseling was recommended. Overall, 12 patients (6%) received recommended treatment. In summary, patients benefited from both TOP DNA and RNA panels while following the same indication as the approved CGP tests. (UMIN000033647).

JAK1 Genomic Alteration Associated With Exceptional Response to Siltuximab in Cutaneous Castleman Disease.

Importance: Castleman disease (CD) is an ultrarare, interleukin-6 (IL-6)-driven lymphoproliferative disorder whose underlying molecular alterations are unknown. Siltuximab (anti-IL-6 antibody) is approved for treatment of this disease. To our knowledge, genomic sequencing of CD has not been reported. Objective: To investigate and identify molecular aberration(s) that help explain the exceptional response to siltuximab in a patient with cutaneous CD. Design, Setting, and Participants: This case study examines data from comprehensive genomic profiling (using targeted next-generation sequencing) of tissue from a patient with cutaneous CD who demonstrated an exceptional response to siltuximab treated at a National Cancer Institute-designated Comprehensive Cancer Center. Interventions: Intravenous siltuximab 12 mg/kg every 3 weeks. Tissue from the patient was interrogated by next-generation sequencing (405 genes). Serum was evaluated for IL-6 levels by enzyme-linked immunoassay. Main Outcomes and Measures: Identification of pretreatment serum IL-6 levels and somatic variants that may explain the exceptional response to siltuximab in this patient with cutaneous CD. Results: Patient pretreatment serum IL-6 levels were normal. Treatment with siltuximab resulted in a complete response lasting 7 years. Next-generation sequencing demonstrated a JAK1V310I missense mutation. Janus Kinase 1 (JAK1) is a crucial signaling component of the IL-6/IL-6 receptor/gp130 machinery. JAK1V310I may induce a conformation change with functional activation effect leading to enhanced sensitivity to the IL-6 ligand. Conclusions and Relevance: Our observations suggest that a JAK1 alteration may explain the underlying biology of a patient's cutaneous CD, as well as the patient's exceptional response to siltuximab.