The Reality of Cost Sharing in Japan.

Financial pressure on younger generation is mounting in Japan, a super-ageing society with staggering economy. The revision on the co-insurance rate for 70-74 with "Standard" category was implemented to mitigate such pressure, seeking better balance across generations in sharing the burden of healthcare cost. It raised the rate from 10% to 20% over the period of five years from 2014 to 2018. This report examined how it changed the share of cost sharing (cost sharing as percentage to total healthcare expenditure), among the 70-74 with "Standard" category in Citizens Health Insurance programme in 44 prefectures. It specifically focused on change in the population's actual share of cost sharing (ASCS) that better reflect the genuine amount of payment actually made by the patients themselves. The average ASCS increased from 7.28% (2013) to 10.78% (2019), resulting wider gap from the statutory planned share of cost sharing (i.e., the statutory co-insurance rate of 10% in 2013, and 20% in 2019). Also found was increased variance among prefectural ASCS, which may suggest a possibility of un-designed effect by the revision, of encouraging a move towards ability and willingness to pay. In terms of cost containment effect, Japan needs to consider various non-conventional options, including review of the current use of healthcare resources. First and foremost, however, the true state of cost sharing should be recognized in terms of ASCS and shared more widely as a reality. Such effort is essential in discussion of how to keep embracing the country's life line, UHC.

[A Case of Spinal Cord Metastasis from Breast Cancer Successfully Treated with Trastuzumab Deruxtecan].

OBJECTIVE: Intramedullary spinal cord metastases(ISCM)are very rare in patients with breast cancer and have a poor prognosis with no established treatment. We report a case of ISCM in a patient with HER2-positive breast cancer who was successfully treated with a novel anti-HER2 agent, trastuzumab deruxtecan(T-DXd, ENHERTU®). CASE: The patient was a 44- year-old woman who underwent surgery for right breast cancer. T-DXd was introduced as the fourth-line metastatic treatment for multiple metastases, including liver, bone, pituitary, brain, and spinal cord metastases. Hematologic and non- hematologic toxicities did not occur during the treatment with T-DXd. T-DXd could be administered continuously for 25 cycles, and symptoms such as numbness in the left lower limb were controlled without progression of the brain and spinal cord, although T-DXd-induced interstitial lung disease was a concern. DISCUSSION: ISCM is a rare metastatic lesion that is difficult to treat with chemotherapy due to the blood-brain barrier (BBB), and there is no established treatment for ISCM. T-DXd has shown promising results in previous clinical trials, including in patients with central nerve system (CNS) metastases, and is expected to be a good treatment option for CNS metastases in clinical practice. CONCLUSION: This successful case of T-DXd for ISCM suggests that T-DXd is an effective treatment option for patients with breast cancer and CNS metastases.

The relationship between ring-type dedicated breast PET and immune microenvironment in early breast cancer.

PURPOSE: 18F-fluorodeoxyglucose (FDG) uptake on positron emission tomography (PET) is related to the biological parameters and prognosis of breast cancer. However, whether whole-body PET (WBPET) and dedicated breast PET (DbPET) can reflect the tumor microenvironment is unclear. This study investigated the relationship between stromal tumor-infiltrating lymphocytes (TILs) and maximum standardized uptake value (SUVmax) in WBPET and DbPET. METHODS: A total of 125 invasive breast cancers underwent WBPET and ring-type DbPET and resected specimens were pathologically assessed. The impact of SUVmax on the tumor biological parameters and TILs was retrospectively evaluated. SUVmax was classified as high and low relative to the median values (WBPET-SUVmax: 2.2 and DbPET-SUVmax: 6.0). RESULTS: SUVmax correlated with tumor size, nuclear grade, Ki-67 labeling index, and TILs in both WBPET and DbPET (all p < 0.001). In multiple linear regression analysis, tumor size, Ki-67 labeling index, and TILs predicted SUVmax in WBPET and DbPET. The cutoff values of tumor size, Ki-67 labeling index, and TILs predicting high SUVmax were 20 mm, 20%, and 20%, respectively. In multivariate analysis, the predictive factors for high SUVmax were tumor size and Ki-67 labeling index for WBPET and tumor size and TILs for DbPET. High SUVmax in DbPET was related to high numbers of TILs after propensity score matching analysis; however, WBPET was not (p = 0.007 and p = 0.624, respectively). CONCLUSIONS: Both SUVmax values in WBPET and DbPET predicted TIL concentration of the primary breast cancer. In DbPET, SUVmax represented the immune microenvironment after adjusting for tumor biological factors.

Prediction of biological characteristics of breast cancer using dual-phase FDG PET/CT.

PURPOSE: The aim of this study was to assess whether the retention index (RI) determined using dual-phase 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) reflects the malignant features of breast cancer. METHODS: A total of 1,523 patients with breast cancer were retrospectively evaluated. PET/CT scans were performed at 1 h and 2 h after FDG administration before treatment. The maximum standardized uptake value (SUVmax) at both time points (SUVmax1 and SUVmax2) in the primary tumour and RI were calculated. Primary tumour tissues were evaluated in terms of biological features, such as histology, nuclear grade, lymphovascular invasion and molecular subtype. RESULTS: Of the 1,523 patients, 463 (30.4%) had luminal A-like, 661 (43.4%) had luminal B-like, 229 (15.0%) had human epidermal growth factor receptor 2-positive (HER2-positive), and 157 (10.3%) triple-negative breast cancer. The median SUVmax1, SUVmax2 and RI values were 2.2, 2.3 and 2.6%, respectively. These metabolic parameters were correlated with tumour size, nodal metastasis, histology, nuclear grade, lymphovascular invasion, and molecular subtype (all P < 0.001). The median RI values were 0% in luminal A-like, 5.3% in luminal B-like, 6.9% in HER2-positive, and 11.4% in triple-negative breast cancer. RI was associated with malignant features when the tumour accumulated a significant amount of FDG. In a subanalysis of patients with tumours of stages T2 to T4, RI was correlated with nodal metastasis, histology, nuclear grade, and molecular subtype (luminal A-like 4.8%, luminal B-like 12.3%, HER2-positive 15.8%, and triple-negative 16.3%). CONCLUSION: RI determined using delayed-phase FDG PET/CT is associated with malignant features in breast cancers with significant FDG uptake. Dual-phase imaging was helpful in distinguishing luminal A-like breast cancer from luminal B-like, HER2-positive, and triple-negative breast cancers.

Identification of Axillary Lymph Node Metastasis in Patients With Breast Cancer Using Dual-Phase FDG PET/CT.

OBJECTIVE. The aim of this study was to assess the diagnostic performance of dual-phase 18F-FDG PET/CT in detecting axillary lymph node metastasis in patients with breast cancer. MATERIALS AND METHODS. A total of 826 patients with breast cancer were retrospectively evaluated. PET/CT scans were performed 1 hour and 2 hours after FDG administration before treatment. The maximum standardized uptake value (SUVmax) in the axillary lymph node at both time points (hereafter referred to as SUVmax1 and SUVmax2, respectively) and the retention index (RI) were calculated. RESULTS. Axillary lymph node metastasis was detected in 285 of 826 patients (34.5%). The median axillary SUVmax1, SUVmax2, and RI in patients with nodal metastasis were higher than those in patients without metastasis (1.5 vs 0.6, 1.6 vs 0.5, and 7.7 vs -3.7, respectively; all p < 0.001). The diagnostic accuracy of axillary SUVmax1 and SUVmax2 was equivalent, and the sensitivity and specificity of SUVmax1 were 74.7% and 83.4%, respectively. Although the performance of the axillary RI was inferior to that of SUVmax1 and SUVmax2, both the SUVmax and the RI were independent predictors of nodal metastasis, and a positive RI suggested axillary lymph node involvement when the SUVmax1 was significantly high. Of 533 patients with category T1-2 breast cancer without lymph node swelling, 101 (19.0%) had pathologic lymph node involvement; the negative predictive value of axillary SUVmax1 was 86.8%. CONCLUSION. Delayed phase imaging identified axillary lymph node metastasis as accurately as standard PET/CT. A high negative predictive value of PET/CT for the detection of nodal metastasis is helpful to avoid surgical axillary assessment in patients with category T1-2 breast cancer without lymph node swelling.

[Challenges in Healthcare Economics of Today's Cancer Treatment].

Healthcare economics concerns with the way in which to distribute and allocate scarce resources that result in maximized outcome. When the expenditure on cancer medicine was examined using the macro data open to the public, it was found to have increased in parallel with the National Medical Care Expenditure. More specifically, the growth rates of the two showed a similar trend in the five years from 2011 to 2015. However, when looked more closely by excluding the patient share and separating the care settings, the result was different. The expenditure in outpatient care displayed a significant increase, implying the influence of chemotherapy shifting to take place more in the outpatient setting. Current discussion on introducing the concept of cost effectiveness into the fee schedule scheme should be based on multidimensional consideration.

Ability of contrast-enhanced ultrasonography to determine clinical responses of breast cancer to neoadjuvant chemotherapy.

OBJECTIVE: We aimed to determine whether contrast-enhanced ultrasonography can predict the effects of neoadjuvant chemotherapy on breast cancer. METHODS: The clinical responses of 63 consecutive patients with breast cancer (T1-4, N0-1, M0) to neoadjuvant chemotherapy between October 2012 and May 2015 were assessed using contrast-enhanced magnetic resonance imaging, positron emission tomography/computed tomography and contrast-enhanced ultrasonography. Perfusion parameters for contrast-enhanced ultrasonography were created from time-intensity curves based on enhancement intensity and temporal changes to objectively evaluate contrast-enhanced ultrasonography findings. The sensitivity, specificity and accuracy of contrast-enhanced ultrasonography, magnetic resonance imaging and positron emission tomography/computed tomography to predict a pathological complete response were compared after confirming the pathological findings of surgical specimens. RESULTS: Twenty-three (36.5%) of the 63 patients achieved pathological complete response. The sensitivity, specificity and accuracy of contrast-enhanced ultrasonography for predicting pathological complete response were 95.7% (82.5-99.2%), 77.5% (69.9-79.5%) and 84.1% (74.5-86.7%). The sensitivity of contrast-enhanced ultrasonography was significantly greater than that of magnetic resonance imaging (95.7 vs. 69.6%, P = 0.047). The specificity and accuracy were significantly greater and tended to be greater, respectively, for contrast-enhanced ultrasonography than positron emission tomography/computed tomography (specificity, 77.5 vs. 52.5%, P = 0.02; accuracy, 84.1 vs. 69.8%, P = 0.057). CONCLUSIONS: Contrast-enhanced ultrasonography might serve as a new diagnostic modality when planning therapeutic strategies for patients with breast cancer after neoadjuvant chemotherapy.

Cystoid Macular Edema following Treatment with Nanoparticle Albumin-Bound Paclitaxel and Atezolizumab for Metastatic Breast Cancer.

Cystoid macular edema (CME) is a rare side effect associated with chemotherapy. Although the development of CME has been reported to occur following treatment with taxane drugs, such as nanoparticle albumin-bound paclitaxel (Nab-PTX), the occurrence of CME with treatment with atezolizumab has not yet been reported. Here, we report the case of a 49-year-old woman who developed CME 19 months into chemotherapy with Nab-PTX and atezolizumab. Improvement was not achieved with steroid injections into the Tenon's sac, and Nab-PTX and atezolizumab treatments were ceased. One month later, there was subjective improvement in her symptoms. Although many reports have indicated that cessation of chemotherapy has successfully improved CME, a specific treatment for CME has not yet been established. Clinicians should be aware of the ophthalmologic side effects and offer immediate treatment if symptoms develop.

Assessment of the expression of microRNAs­221­3p, ­146a­5p, ­16­5p and BCL2 in oncocytic carcinoma of the breast: A case report.

Oncocytic carcinoma of the breast is rare and its molecular profiles remain poorly understood. MicroRNAs (miRNAs/miRs) have been identified as contributors to carcinogenesis at the post-transcriptional level; thus, an aberrant expression of miRNAs has attracted attention as a potential biomarker of numerous diseases, including cancer. The present study reports the case of a 76-year-old woman diagnosed with oncocytic carcinoma of the breast. Considering the distinctive feature of oncocytic carcinoma of the breast, which is the presence of granular eosinophilic cytoplasm containing numerous mitochondria, the present study hypothesized that the expression of mitochondria-related miRNAs could be altered in oncocytic carcinomas. Aberrant expression levels of the miRNAs previously reported as mitochondria-related miRNAs, such as miR-221-3p, -146a-5p and -16-5p, were revealed in tissue from specimens of oncocytic carcinoma of the breast, compared with that of a more typical type of invasive ductal carcinoma of the breast. The present study highlights the changes in miRNA expression in oncocytic carcinoma of the breast, suggesting its potential as a biomarker for diagnosis.

Mechanistic analysis of the antitumor efficacy of human natural killer cells against breast cancer cells.

We investigated the role of human natural killer (NK) cells in the peripheral blood (PB) and liver in controlling breast cancer. The proportion of NK cells among liver mononuclear cells was significantly higher than among PB mononuclear cells. Liver NK cells inductively expressed higher levels of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) than PB NK cells in response to interleukin-2 (IL-2). Liver NK cells displayed higher cytotoxicity against various breast cancer cell lines (MDA-MB231, MDA-MB453, MDA-MB468, and MCF-7) after IL-2 stimulation than did PB NK cells. Anti-HER2 monoclonal antibody (mAb) promoted the cytotoxicity of both the types of NK cells toward HER2-expressing cell lines. All breast cancer cell lines highly expressed death-inducing TRAIL receptors, death receptor 4, but did not express death-inhibitory receptors (DcR1 and DcR2). Both PB and liver NK cell-induced cytotoxicity was inhibited partially by anti-TRAIL mAb and more profoundly by the combination of anti-TRAIL mAb and concanamycin A, indicating that TRAIL and perforin are involved. IL-2-stimulated liver and PB NK cells exhibited upregulated expression of CXCR3, which bind to the chemokines CXCL9, CXCL10, and CXCL11 secreted by breast cancer cells. We also found that IFN-γ promoted the production of CXCL10 from breast cancer cells. The results of this study show that IFN-γ secreted from NK cells likely promotes the production of CXCL10 from breast cancer cells, which in turn accelerates the migration of CXCR3-expressing NK cells into the tumor site. These findings suggest the possibility of a therapeutic approach by either activation of endogenous PB and liver NK cells or adoptive transfer of in vitro-activated autologous NK cells.

[A resected case of complete response after treatment with S-1 for recurrent squamous cell carcinoma component of the breast].

A resected case of complete response after treatment with S-1 for recurrent squamous cell carcinoma component of the breast is presented.A 65-year-old woman was admitted to another hospital because of a left breast tumor. A tumor approximately 6 cm in diameter was palpable in the subareolar-lower (DBE) region of the left breast; the diagnosis was breast cancer. We performed mastectomy and axillary lymph node dissection. The pathological diagnosis revealed squamous cell carcinoma of the left breast(pT3N1M0, Stage III A). FEC chemotherapy, a standard chemotherapy regimen for general breast cancer, was performed as first-line adjuvant therapy, but was withdrawn after 1 course due to sepsis shock. Weekly PTX chemotherapy as second-line treatment was also withdrawn after six courses due to interstitial pneumonia. Few skin rashes were observed along the incision scar of the left breast, but biopsy revealed skin invasion by local recurrence of squamous cell carcinoma of the breast. Treatment with S-1 was performed for 8 months, and she underwent resection of left skin, fat tissue, and underlying muscle, including the recurrent region. No residual primary carcinoma foci was found in the resected specimen; therefore, the pathological diagnosis revealed complete response for the squamous cell carcinoma component.

Endobronchial ultrasound-guided transbronchial needle aspiration facilitating diagnosis of sarcoidosis in a breast cancer patient with multiple lymphadenopathy: a case report.

BACKGROUND: Sarcoidosis is a benign systemic granulomatous disorder of unknown etiology. Cell-mediated immunity disorder is often found in sarcoidosis patients, and an association between malignant tumors and sarcoidosis has been suggested. Sarcoidosis and malignant disease can occur simultaneously or sequentially, leading to misdiagnosis and mistreatment. Sarcoidosis is diagnosed clinically, radiologically, and histologically. We report herein a case of sarcoidosis diagnosed by endobronchial ultrasound-guided transbronchial needle aspiration from the mediastinal lymph nodes of a breast cancer patient. CASE PRESENTATION: The patient was a 70-year-old Asian woman who presented with right breast tumor. A 20-mm movable mass was identified in the inferolateral quadrant of the right breast, and mammography revealed a spiculated mass with calcification. Ultrasonography revealed a mass with internal hypoechogenicity, and biopsy revealed estrogen receptor-positive, human epidermal growth factor receptor 2-positive invasive ductal carcinoma. Positron emission tomography/computed tomography showed multiple lymphadenopathy including mediastinal lymph nodes, with fluorodeoxyglucose accumulation in those nodes suggesting breast cancer metastases. Endobronchial ultrasound-guided transbronchial needle aspiration of a mediastinal lymph node revealed noncaseous epithelioid granuloma. Due to a history of uveitis and elevated soluble interleukin 2 receptor, lymphadenopathy due to sarcoidosis and stage IIA breast cancer were diagnosed. Right partial mastectomy and axillary lymph node dissection were performed after preoperative chemotherapy. No exacerbation of sarcoidosis symptoms has been observed during treatment. CONCLUSION: We report a case of breast cancer in which sarcoidosis could be diagnosed based on endobronchial ultrasound-guided transbronchial needle aspiration, a history of uveitis, and elevated soluble interleukin 2 receptor despite fluorodeoxyglucose positron emission tomography/computed tomography suggesting multiple lymph node metastases. This report emphasizes the importance of differential diagnosis of lymph node involvements in cancer patients.

Association between CA 15­3 and progression of interstitial lung disease in a case of coexisting systemic sclerosis and recurrent breast cancer: A case report.

Carbohydrate antigen 15-3 (CA 15-3) is known as a specific tumor marker for breast cancer, the main use of which is monitoring therapy in patients with advanced breast cancer. Either systemic sclerosis (SSc)-interstitial lung disease (ILD) or pulmonary arterial hypertension is currently the leading cause of disease-related morbidity and mortality in patients with scleroderma. Although CA 15-3 has been investigated as a biomarker in SSc-ILD, its role remains unclear. The current report presented a case of recurrent breast cancer diagnosed with SSc-ILD during treatment. The patient, at 63 years old, experienced shortness of breath with minimal exertion after four cycles of perutuzumab, trastuzumab and weekly paclitaxel. Computed tomography (CT) revealed ground-glass opacities and linear shadows in the peripheral lower lobes of both lungs. Although the development of lung involvement associated with breast cancer, such as carcinomatous lymphangitis, was initially suspected, because of the increase in CA 15-3, skin biopsies were taken from the left index finger base and extension side of the left elbow, which demonstrated increased thickness of the dermis, leading to a diagnosis of SSc-ILD. The findings in this case suggested the importance of considering a differential diagnosis, including ILD, concurrently while screening for the progression of recurrent breast cancer when encountering patients with breast cancer and elevated levels of CA 15-3.

A case of HER-2-positive recurrent breast cancer showing a clinically complete response to trastuzumab-containing chemotherapy after primary treatment of triple-negative breast cancer.

We report a case of HER-2-positive recurrent breast cancer showing a clinically complete response to trastuzumab-containing chemotherapy 6 years after primary treatment of triple-negative breast cancer. The primary tumor was negative for HER-2 as determined by immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) (1+, and ratio, 1.1), but examination of the recurrent lymph node metastasis showed positivity for HER-2 by FISH (ratio, 5.2). No lesions were detected in either her left breast or in other organs, and the patient was diagnosed as having HER-2-positive recurrent disease. Combination chemotherapy using weekly paclitaxel and trastuzumab was initiated, and a clinically complete response was achieved. This report suggests the benefit of routine evaluation of HER-2 status in recurrent breast cancer with the introduction of HER-2-targeting agents.

Spontaneous regression of breast cancer with immune response: a case report.

BACKGROUND: Spontaneous regression (SR) is a rare phenomenon in which a cancer disappears or remits without treatment. We report a case of breast cancer that showed spontaneous tumor regression in the surgical specimen after core needle biopsy. CASE PRESENTATION: A 59-year-old woman came to our hospital complaining of a painful lump in the right breast. In the upper-outer quadrant of the right breast, a tumor with an unclear boundary, 30 mm in diameter, was palpable. In pathological findings from needle biopsy, the tumor was diagnosed as solid-type invasive ductal breast carcinoma. Partial coagulation necrosis was generated in estrogen receptor-negative, HER2-negative, and AE1/AE3-positive ductal carcinoma without infiltration of lymphocytes. Surgery for right breast cancer was then performed. Histological examination of the surgical specimen revealed the tumor was invasive ductal carcinoma with lymphocyte infiltration, coagulation necrosis, and fibrous tissue with hemosiderin. The tumor formed a solid nest, 3 mm in diameter, suggesting the possibility of SR. CONCLUSIONS: Immune responses, infection, hormones, surgical stress, and ischemia have been reported as mechanisms of SR. The findings in this case strongly suggest that SR of breast cancer is associated with anti-tumor immune responses.

Asymptomatic solitary metastasis to the stomach from breast cancer: A case report.

Distant metastases from breast cancer are frequently found in bones, lungs and the liver. Metastasis to the stomach is rare, and its clinical presentation remains unclear. The present report describes a case of isolated gastric metastasis from breast cancer identified by contrast-enhanced computed tomography (CT). A 45-year-old female patient underwent right mastectomy and axillary lymph node dissection after preoperative chemotherapy for right invasive lobular breast carcinoma T4bN2M0, stage IIIB. Postoperative radiotherapy and endocrine therapy with tamoxifen for 5 years were performed. CT for postoperative follow-up at 52 years old revealed thickening of the stomach wall. Although the patient was asymptomatic, erosive mucosa was observed on the gastric body during gastroscopy. The gastric lesion was immunohistochemically diagnosed as metastatic luminal disease from the breast cancer. Positron emission tomography/CT revealed no abnormal accumulation suggesting metastasis to other organs. Palbociclib and fulvestrant treatment were initiated for gastric metastasis. Invasive lobular breast carcinoma results in gastrointestinal metastasis, including the stomach, more frequently than invasive ductal breast carcinoma. However, most gastric metastases occur simultaneously with systemic metastases. Solitary metastasis to the stomach without symptoms as in this case has rarely been reported. The possibility of gastric metastasis should be considered among the differential diagnoses, even in the absence of symptoms, when gastrointestinal abnormalities are seen on CT in patients with a history of breast cancer.

Dedicated breast PET for detecting residual disease after neoadjuvant chemotherapy in operable breast cancer: A prospective cohort study.

PURPOSE: Diagnostic methods to evaluate the response to neoadjuvant chemotherapy (NAC) for breast cancer have not been established. Dedicated breast PET (DbPET) is a high-resolution molecular breast imaging method, and we investigated the capability of DbPET to predict residual primary tumors after NAC compared with whole-body PET (WBPET). METHODS: Forty-five patients (47 tumors) underwent WBPET and ring-type DbPET after NAC, and the tumors were completely resected between January 2016 and March 2017. The pathological response was classified as complete remission (ypT0), residual intraductal disease (ypTis), or residual invasive disease (ypT ≥ 1). Standardized uptake value (SUV) and tumor-to-normal tissue ratio (TNR) were assessed. RESULTS: Twelve patients achieved ypT0 and five developed ypTis. DbPET detected all cases of ypTis, and WBPET detected only one case of ypTis. The sensitivity, specificity, and accuracy of WBPET for ypTis and/or ypT ≥ 1 were 54.3%, 83.3%, and 61.7%, respectively, and those of DbPET were 77.1%, 83.3%, and 78.7%, respectively. In the ypT0/ypTis/ypT ≥ 1 groups, the median WBPET-SUV, DbPET-SUV, and DbPET-TNR was 1.0/0.9/1.1, 1.7/1.8/2.2, and 1.0/1.6/1.7 (P = .134, .077, and 0.008), respectively. Areas under the curves of WBPET-SUV, DbPET-SUV, and DbPET-TNR for predicting ypTis and/or ypT ≥ 1 were 0.610, 0.648, and 0.807, respectively. CONCLUSIONS: DbPET was more accurate than WBPET in detecting residual primary tumors after NAC, particularly intraductal carcinoma. TNR was the better parameter for pathological evaluation compared with SUV.

Portable impulse-radar detector for breast cancer: a pilot study.

Microwave breast imaging is a painless and nonradiation method. This pilot study aimed to evaluate the detective capability and feasibility of a prototype of a portable breast cancer detector using a radar-based imaging system. Five patients with histologically confirmed breast cancers with a minimum diameter of 1 cm were enrolled in this study. The antenna array dome of the device was placed on the breast of the patient in a supine position for 15 min per single examination. The primary endpoint was a detection rate of breast cancers. The secondary endpoints were positional accuracy and adverse event. All five targeted breast tumors were detected and were visualized at the sites confirmed by other diagnostic modalities. Among five tumors, one was not detected via mammography because of heterogeneously dense breast and another was a microinvasive carcinoma of invasive tumor size 0.5 mm. No study-related adverse events occurred. The prototype of a portable breast cancer detector has sufficient detective capability, is safe for clinical use, and might detect an early stage breast cancer, such as noninvasive carcinoma. Future developments should focus on further decreasing the size of the machine and shortening inspection time.

Which type of breast cancers is undetectable on ring-type dedicated breast PET?

OBJECTIVES: To assess the factors causing tumor undetectability on ring-type dedicated breast positron emission tomography (DbPET). METHODS: A total of 265 patients (288 tumors) underwent DbPET and contrast-enhanced magnetic resonance imaging (MRI) in a prone position. The distance between the shallowest part of the breast tumor and the front end of the pectoralis major muscle on MRI was considered as the tumor-to-chest wall distance. RESULTS: Twenty-four tumors (8.3%) were not visualized via DbPET. The tumor-to-chest wall distance for undetectable tumors was shorter than that of the detectable tumors (23.0 mm vs 38.5 mm, P < 0.001). Multivariate analysis indicated that proximity to the chest wall and low-grade tumors were independent predicting factors for undetectable cancers. Among the 24 undetectable cancers, 15 tumors were proximal to the chest wall, suggesting that they were outside or at the edge of field of view (FOV), and 7 were low-grade tumors, suggesting insignificant 18F-fluorodeoxyglucose (FDG) uptake. CONCLUSIONS: The factors of undetectable breast cancers on DbPET are classified into two types; outside or at the edge of FOV and insignificant FDG uptake.

Role of 18F-PET/CT in Predicting Prognosis of Patients With Breast Cancer After Neoadjuvant Chemotherapy.

BACKGROUND: Breast cancer can be assessed preoperatively and postoperatively using 18F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT). We prospectively analyzed the maximum baseline standardized uptake value (SUVmax) derived from FDG PET/CT to predict the outcomes after neoadjuvant chemotherapy (NAC) for breast cancer. PATIENTS AND METHODS: We assessed 130 consecutive female patients with primary breast cancer (mean age, 53.9 years) using PET/CT before and after NAC. The SUVmax before (pre-SUVmax) and after (post-SUVmax) NAC and the SUVmax reduction rates (ΔSUVmax) after NAC with sequential anthracyclines and a taxane were assessed to predict the pathologic complete response (pCR) and prognosis. RESULTS: Of the 130 patients, 30 (23.1%) achieved a pCR. The pCR rate of the patients with human epidermal growth factor receptor 2-positive (HER2+) and triple-negative (TN) breast cancer was 52.8% and 40.0%, respectively. In contrast, only 1.4% of those with estrogen receptor-positive and HER2- cancer achieved a pCR. The post-SUVmax correlated closely with the pCR (area under the curve, 0.700) but not with the pre-SUVmax and ΔSUVmax (area under the curve, 0.414 and 0.589, respectively) in patients with HER2+ and TN breast cancer. The post-SUVmax was associated with the pCR (P = .019), and multivariate analysis selected post-SUVmax as a significant prognostic factor (P = .014). The post-SUVmax correlated significantly with recurrence-free survival and recurrence (P = .026, log-rank test). CONCLUSION: The SUVmax determined after NAC using FDG PET/CT can predict for the pCR and the prognosis of patients with operable HER2+ and TN breast cancer. In the future, additional chemotherapy will be applied according to the post-SUVmax after standard NAC to achieve a pCR or omit surgery.