Assessment for the timing of comprehensive genomic profiling tests in patients with advanced solid cancers.

Comprehensive genomic profiling (CGP) tests have been covered by public insurance in Japan for patients with advanced solid tumors who have completed or are completing standard treatments or do not have them. Therefore, genotype-matched drug candidates are often unapproved or off-label, and improving clinical trial access is critical, involving the appropriate timing of CGP tests. To address this issue, we analyzed the previous treatment data for 441 patients from an observational study on CGP tests discussed by the expert panel at Hokkaido University Hospital between August 2019 and May 2021. The median number of previous treatment lines was two; three or more lines accounted for 49%. Information on genotype-matched therapies was provided to 277 (63%). Genotype-matched clinical trials were ineligible because of an excess number of previous treatment lines or use of specific agents were found in 66 (15%) patients, with the highest proportion in breast and prostate cancers. Many patients met the exclusion criteria of one to two or more treatment lines across cancer types. In addition, previous use of specific agents was a frequent exclusion criterion for breast, prostate, colorectal, and ovarian cancers. The patients with tumor types with a low median number (two or fewer) of previous treatment lines, including most rare cancers, primary unknown cancers, and pancreatic cancers, had significantly fewer ineligible clinical trials. The earlier timing of CGP tests may improve access to genotype-matched clinical trials, with their proportion varying by cancer type. Each relevant society needs to advocate the desirable timing of CGP testing nationwide.

[Interstitial Pneumonia Caused by Olaparib during Treatment of Breast Cancer-A Case Report].

The characteristic adverse events of olaparib, a PARP inhibitor, are nausea, vomiting, and anemia, and interstitial pneumonia is rarely reported. We report a case of interstitial pneumonia following the treatment of a metastatic breast cancer with olaparib. The patient was a 34-year-old woman. In March 2018, she was diagnosed with stage Ⅳ breast cancer(multiple lung metastases). She was treated with epirubicin and cyclophosphamide followed by paclitaxel. In November 2018, brain and spinal cord metastases were detected, and she was treated with radiation. In December 2018, a BRCA1 deleterious mutation was confirmed, and treatment with olaparib was initiated. Six weeks later, olaparib was discontinued due to anemia; it also caused interstitial pneumonia. The interstitial pneumonia resolved following multidisciplinary treatment during hospitalization. Subsequently, she was treated with cyclophosphamide/methotrexate/fluorouracil. It is necessary to consider interstitial pneumonia as an adverse effect of olaparib.

[A Case of Male Recurrent Breast Cancer Successfully Treated with Bevacizumab plus Paclitaxel Therapy for Carcinomatous Pericarditis].

We report the case of a 44-year-old male who underwent mastectomy plus axillary lymph node dissection after neoadjuvant chemotherapy for left breast cancer. During adjuvant therapy, multiple bone metastases and pericardial effusion were detected. Pericardial drainage was mandated for the patient, although no malignant cells were found. Despite the change in treatment, pericardial effusion worsened. Based on clinical findings, the patient was diagnosed with carcinomatous pericarditis and was switched to bevacizumab plus paclitaxel therapy. CT at 5 months showed improved pericardial effusion; treatment is ongoing.

[Safety and Tolerance of Dose-Dense Epirubicin and Cyclophosphamide (EC) with Pegfilgrastim for Japanese Patients with Early Breast Cancer].

With the approval of pegfilgrastim, the use of dose-dense epirubicin and cyclophosphamide (EC) for breast cancer has become acceptable in Japan. Thus, we aimed to evaluate its safety and tolerability in Japanese patients. Nine breast cancer patients with a high risk of preoperative or postoperative recurrence received EC therapy(epirubicin 90 mg/m(2) and cyclo- phosphamide 600 mg/m(2))for 4 cycles every 2 weeks in combination with a subcutaneous injection of pegfilgrastim (3.6 mg) on day 2 of each cycle. Treatment was discontinued in 1 and extended in 1 of the 9 patients, and the mean relative dose intensity(RDI)was good at 0.93. No serious adverse events were observed, indicating good tolerability. The regimen has potential for use in cases in which the treatment dose needs to be increased. grade 4 neutropenia was observed in all the 9 patients on day 8, with 6 patients developing febrile neutropenia. In Japan, data on changes in neutrophil count associated with pegfilgrastim administration under anthracycline-based chemotherapy are currently insufficient, and further study is required.

Genetic heterogeneity during breast cancer progression in young patients.

BACKGROUND: Because a number of years may be required for normal cells to develop into carcinoma, genes involved in tumorigenesis and progression might differ among breast cancers in young women and those in older women. The present study sought to analyze subclonality during breast cancer evolution as well as diversity within each individual in our young patients' cohort. METHODS: A total of 13 women aged <35 years at diagnosis with early breast cancer were recruited. Serial sections of breast samples consisting of synchronous invasive carcinoma, adjacent ductal carcinoma in situ (DCIS), normal breast tissue, and metastatic lymph nodes were collected and prepared for immunohistochemical analysis of estrogen receptor, progesterone receptor, HER2, and Ki67, and for extraction of genomic DNA. Germline and somatic gene alterations of genomic DNA were examined by targeted sequencing. RESULTS: Genomic DNA from 13 blood samples and 36 breast tissues consisting of 14 invasive carcinomas, nine adjacent DCIS, 11 normal breast tissues, and two metastatic lymph nodes were successfully sequenced. Germline gene alterations including pathogenic variants and gene alterations that were not yet evaluated for their clinical significance were detected in all patients but one. Somatic gene alterations were identified in eight invasive carcinomas, five DCIS, and one metastatic lymph node. Different somatic gene alterations between invasive carcinoma and DCIS were detected in two patients. Somatic gene mutations were present in non-neoplastic tissues in three patients. No two patients had the same gene alterations. CONCLUSION: Our results reveal diversity within each individual during breast cancer progression.

Impact of clinical targeted sequencing on endocrine responsiveness in estrogen receptor-positive, HER2-negative metastatic breast cancer.

Clinical targeted sequencing allows for the selection of patients expected to have a better treatment response, and reveals mechanisms of resistance to molecular targeted therapies based on actionable gene mutations. We underwent comprehensive genomic testing with either our original in-house CLHURC system or with OncoPrime. Samples from 24 patients with estrogen receptor-positive, human epidermal growth factor receptor 2-negative metastatic breast cancer underwent targeted sequencing between 2016 and 2018. Germline and somatic gene alterations and patients' prognosis were retrospectively analyzed according to the response to endocrine therapy. All of the patients had one or more germline and/or somatic gene alterations. Four patients with primary or secondary endocrine-resistant breast cancer harbored germline pathogenic variants of BRCA1, BRCA2, or PTEN. Among somatic gene alterations, TP53, PIK3CA, AKT1, ESR1, and MYC were the most frequently mutated genes. TP53 gene mutation was more frequently observed in patients with primary endocrine resistance compared to those with secondary endocrine resistance or endocrine-responsive breast cancer. Recurrent breast cancer patients carrying TP53-mutant tumors had significantly worse overall survival compared to those with TP53-wild type tumors. Our 160-gene cancer panel will be useful to identify clinically actionable gene alterations in breast cancer in clinical practice.

Clinical benefit of treatment after trastuzumab emtansine for HER2-positive metastatic breast cancer: a real-world multi-centre cohort study in Japan (WJOG12519B).

BACKGROUND: Trastuzumab emtansine (T-DM1) treatment for human epidermal growth factor receptor-2 (HER2)-positive metastatic breast cancer after taxane with trastuzumab and pertuzumab is standard therapy. However, treatment strategies beyond T-DM1 are still in development with insufficient evidence of their effectiveness. Here, we aimed to evaluate real-world treatment choice and efficacy of treatments after T-DM1 for HER2-positive metastatic breast cancer. METHODS: In this multi-centre retrospective cohort study involving 17 hospitals, 325 female HER2-positive metastatic breast cancer patients whose post-T-DM1 treatment began between April 15, 2014 and December 31, 2018 were enrolled. The primary end point was the objective response rate (ORR) of post-T-DM1 treatments. Secondary end points included disease control rate (DCR), progression-free survival (PFS), time to treatment failure (TTF), and overall survival (OS). RESULTS: The median number of prior treatments of post-T-DM1 treatment was four. The types of post-T-DM1 treatments included (1) chemotherapy in combination with trastuzumab and pertuzumab (n = 102; 31.4%), (2) chemotherapy concomitant with trastuzumab (n = 78; 24.0%), (3), lapatinib with capecitabine (n = 63; 19.4%), and (4) others (n = 82; 25.2%). ORR was 22.8% [95% confidence interval (CI): 18.1-28.0], DCR = 66.6% (95% CI 60.8-72.0), median PFS = 6.1 months (95% CI 5.3-6.7), median TTF = 5.1 months (95% CI 4.4-5.6), and median OS = 23.7 months (95% CI 20.7-27.4). CONCLUSION: The benefits of treatments after T-DM1 are limited. Further investigation of new treatment strategies beyond T-DM1 is awaited for HER2-positive metastatic breast cancer patients.

HER2 Gene Amplification in ER-positive HER2 Immunohistochemistry 0 or 1+ Breast Cancer With Early Recurrence.

BACKGROUND/AIM: In estrogen receptor (ER)-positive, human epidermal growth factor receptor 2 (HER2)-negative breast cancer, standard chemotherapies as well as adjuvant endocrine therapy might not be enough for prevention of early relapse. MATERIALS AND METHODS: We focused on ER-positive, HER2 immunohistochemistry (IHC) 0 or 1+ breast cancer, and retrospectively examined HER2 gene amplification and TP53 mutation in breast cancer tissues in patients with or without early recurrence. Post-relapse survival in patients with early recurrence was also analyzed by mutation status of HER2 and TP53. RESULTS: Surprisingly, amplification of the HER2 gene was found in 15% of patients with early recurrence. None of the patients without relapse had HER2-amplified tumors. Post-relapse survival in patients with HER2 gene amplification and/or TP53 mutation in primary tumors was shorter than that in patients without these mutations, especially among postmenopausal women. CONCLUSION: HER2 gene amplification exists in ER-positive, HER2 IHC 0 or 1+ breast cancer in patients who developed early distant metastasis.

Tamoxifen withdrawal in women with progressive metastatic breast cancer: a case series of six patients.

Estrogen receptor (ER)-positive metastatic breast cancers after a period of response to tamoxifen develop resistance, and the disease progresses clinically. Domination of partial agonistic activity of tamoxifen over its antagonist activity has been implicated as one of the mechanisms for acquired tamoxifen resistance. Six patients with ER-positive, human epidermal growth factor receptor 2 (HER2)-negative metastatic breast cancer who were treated with tamoxifen withdrawal were retrospectively reviewed. Three patients were premenopausal and three were postmenopausal at the beginning of this treatment. Three patients had stage IV disease and three had recurrent breast cancers with median disease-free intervals of 153 months. The treatment lines of tamoxifen therapy were first-line in two, second-line in two, and third-line in one patient. One patient had relapsed during adjuvant tamoxifen therapy. The median duration of tamoxifen therapy was 16 months. The metastatic disease sites at the time of tamoxifen withdrawal were lymph nodes in six, bone in three, chest wall in one, lung in two, pleura in one, and liver in one patient. The median duration of tamoxifen withdrawal was 6.5 months (range 5-> 23 months). Five of six patients had clinical benefits with tamoxifen withdrawal: partial response in one, long stable disease (SD) in four, and SD in one patient. Five patients were treated with aromatase inhibitors after tamoxifen withdrawal. Two patients had metastatic lymph nodes examined by multi-gene panel testing, and both of their tumors had the AKT1 E17K somatic mutation. One patient also had a BRCA1 germline mutation. Tamoxifen withdrawal at the time of tumor progression while on treatment might be an important treatment option, especially for women with highly endocrine-responsive disease.

PIK3CA mutation, reduced AKT serine 473 phosphorylation, and increased ERα serine 167 phosphorylation are positive prognostic indicators in postmenopausal estrogen receptor-positive early breast cancer.

Although endocrine therapy is the most important treatment option in estrogen receptor (ER)-positive breast cancer, new strategies, such as molecular targeted agents together with endocrine therapy are required to improve survival. PIK3CA is the most frequent mutated gene in ER-positive early breast cancers, and PIK3CA mutation status is reported to affect activation of AKT and ERα. Moreover, recent studies demonstrate that patients had a better prognosis when tumors expressed ER, androgen receptor (AR), and vitamin D receptor (VDR). In this study, we examined expression of AR and VDR, phosphorylation of AKT serine (Ser) 473 (AKT phospho-Ser473) and ERα Ser167 (ERα phospho-Ser167) by immunohistochemistry in ER-positive, HER2-negative early breast cancer. PIK3CA gene mutations were also detected in genomic DNA extracted from tumor blocks. Correlations between these biological markers, clinicopathological factors and prognosis were analyzed. Levels of AKT phospho-Ser473 were significantly higher in premenopausal women than in postmenopausal women. In contrast, AR expression was significantly higher in postmenopausal women than in premenopausal women. PIK3CA mutations were detected in 47% in premenopausal women and 47% in postmenopausal women. Postmenopausal women with PIK3CA wild-type tumors had significantly worse disease-free survival than patients with PIK3CA mutant tumors. Low levels of AKT phospho-Ser473 and high levels of ERα phospho-Ser167 were strongly associated with increased disease-free survival in postmenopausal women. Evaluation of ERα activation, in addition to PIK3CA mutation status, might be helpful in identifying patients who are likely to benefit from endocrine therapy alone versus those who are not in postmenopausal ER-positive early breast cancer.

Genetic and environmental factors and serum hormones, and risk of estrogen receptor-positive breast cancer in pre- and postmenopausal Japanese women.

Breast cancer incidence in Japanese women has more than tripled over the past two decades. We have previously shown that this marked increase is mostly due to an increase in the estrogen receptor (ER)-positive, HER2-negative subtype. We conducted a case-control study; ER-positive, HER2-negative breast cancer patients who were diagnosed since 2011 and women without disease were recruited. Environmental factors, serum levels of testosterone and 25-hydroxyvitamin D, and common genetic variants reported as predictors of ER-positive breast cancer or found in Asian women were evaluated between patients and controls in pre- and postmenopausal women. To identify important risk predictors, risk prediction models were created by logistic regression models. In premenopausal women, two environmental factors (history of breastfeeding, and history of benign breast disease) and four genetic variants (TOX3-rs3803662, ESR1-rs2046210, 8q24-rs13281615, and SLC4A7-rs4973768) were considered to be risk predictors, whereas three environmental factors (body mass index, history of breastfeeding, and hyperlipidemia), serum levels of testosterone and 25-hydroxyvitamin D, and two genetic variants (TOX3-rs3803662 and ESR1-rs2046210) were identified as risk predictors. Inclusion of common genetic variants and serum hormone measurements as well as environmental factors improved risk assessment models. The decline in the birthrate according to recent changes of lifestyle might be the main cause of the recent notable increase in the incidence of ER-positive breast cancer in Japanese women.