An approach for improvement of the accuracy of cancer gene panel testing.

BACKGROUND: Tissue-based comprehensive genomic profiling (CGP) is increasingly being employed for genotype-directed therapies in patients with advanced cancer. However, tissue availability may limit their potential applications. In Japan, the cost of cancer gene panel tests is covered by public insurance for patients diagnosed with advanced solid tumors once in their lifetime. Therefore, it is essential to improve the success rate (reportability) and accuracy of CGP tests. The purpose of this study was to identify the factors associated with efficient and accurate CGP testing using relevant information obtained from real-world data. METHODS: This study included 159 samples analyzed using tumor-only panel FoundationOne® CDx cancer genome profiling (F1CDx) and 85 samples analyzed using matched-pair panel OncoGuide™ NCC Oncopanel system (NCCOP) at St. Marianna University Hospital. Sample characteristics (fixation conditions, storage period, histology, tumor cell ratio, and genomic tumor cell content), CGP performance, and quality control status were evaluated across all 244 tested samples. RESULTS: In 237/244 samples (97.1%), CGP testing results were successfully obtained [F1CDx, 99.4% (158/159) and NCCOP, 92.9% (79/85)]. An increased number of fibroblasts, inflammatory cells, and necrotic tumor cells, long-term storage, and/or prolonged fixation of tissue sections were involved in the unreported results and/or qualified CGP results. In addition, a negative correlation between median insert size values and ΔΔCq was observed in the NCCOP system. CONCLUSION: We identified various factors associated with efficient and accurate CGP testing using relevant information obtained from real-world data, suggesting that thorough selection and preparation of tissue sections could optimize CGP and maximize useful information.

[A Case of Long-Term Survival after Multidisciplinary Treatment for Gastrointestinal Neuroendocrine Carcinoma].

A 55-year-old man was admitted to our hospital for examination and treatment of a transverse colon tumor detected at a nearby hospital. After CT, FDG-PET, and laparotomy biopsy, he was diagnosed with neuroendocrine cancer(Ki-67 index 40%)without distant metastasis. He underwent transverse colectomy. The pathological diagnosis was transverse colon neuroendocrine cancer(Ki-67 index 24.7%). Six courses of carboplatin and etoposide therapy as adjuvant chemotherapy were administered. Seven months after surgery, he developed lung metastasis that was surgically removed by partial lung resection. Eighteen months after the initial surgery, liver metastasis developed in S5 and S8. A right hepatic lobectomy was performed and there has been no recurrence after hepatectomy. The patient remains alive at 3 years and 4 months after initial treatment.

A case of pheochromocytoma with a marked decrease in catecholamine levels after rupture in which a good outcome was achieved by elective surgery.

Changes in imaging findings and hormone levels before and after pheochromocytoma rupture, as well as detailed histopathology of resected tumors, have rarely been reported. A 52-year-old woman developed hypertension and diabetes mellitus in 2014, but despite treatment with antihypertensive and hypoglycemic drugs, good control was not achieved. On April 2, 2016, the patient started to have headaches and palpitations, and on April 6, she visited our hospital. Plain computed tomography (CT) of the abdomen showed a 4-cm, isodense mass in the left adrenal gland, and the patient was hospitalized for further examination. Because the patient had hypertension, tachycardia, and hyperglycemia on admission, therapies for those were started. Catecholamine levels were markedly elevated. However, after the patient developed left flank pain on Day 4, antihypertensive and insulin therapies were no longer required. Plain CT then showed heterogeneous high density areas in the left adrenal mass. On Day 7, 3 meta-iodobenzylguanidine scintigraphy showed no abnormal uptake. On Day 8, contrast CT showed low density areas within the left adrenal tumor and contrast enhancement of the tumor margins, and catecholamine levels were markedly decreased. Elective left adrenal tumor resection was performed on Day 49. The capsule of the resected tumor was ruptured. Histopathology showed widespread hemorrhagic necrosis and viable cell components in the tumor margins. Positive chromogranin A staining of the tumor cells confirmed a diagnosis of pheochromocytoma. This patient displayed remarkable changes in imaging findings and hormone levels before and after pheochromocytoma rupture. Pheochromocytoma rupture and hemorrhagic necrosis were confirmed histopathologically.