Arterial Calcification Disappearance in Breast Imaging: A Key Indicator for Transition to Invasive Ductal Carcinoma.

A woman in her 70s, initially suspected of having fibroadenoma due to a well-defined mass in her breast, underwent regular mammography and ultrasound screenings. Over several years, no appreciable alterations in the mass were observed, maintaining the fibroadenoma diagnosis. However, in the fourth year, an ultrasound indicated slight enlargement and peripheral irregularities in the mass, even though the mammography images at that time showed no alterations. Interestingly, mammography images over time showed the gradual disappearance of previously observed arterial calcification around the mass. Pathological examination eventually identified the mass as invasive ductal carcinoma. Although the patient had breast tissue arterial calcification typical of atherosclerosis, none was present around the tumor-associated arteries. This case highlights the importance of monitoring arterial calcification changes in mammography, suggesting that they are crucial indicators in breast cancer diagnosis, beyond observing size and shape alterations.

Prognostic impact of adjuvant endocrine therapy for estrogen receptor-positive and HER2-negative T1a/bN0M0 breast cancer.

PURPOSE: Mammography screening has increased the detection of subcentimeter breast cancers. The prognosis for estrogen receptor (ER)-positive and human epidermal growth factor receptor 2 (HER2)-negative T1a/bN0M0 breast cancers is excellent; however, the necessity of adjuvant endocrine therapy (ET) is uncertain. METHODS: We evaluated the effectiveness of adjuvant ET in patients with ER-positive and HER2-negative T1a/bN0M0 breast cancer who underwent surgery from 2008 to 2012. Standard ET was administrated after surgery. The primary endpoint was the cumulative incidence of distant metastasis. All statistical tests were 2-sided. RESULTS: Adjuvant ET was administered to 3991 (83%) of the 4758 eligible patients (1202 T1a [25.3%] and 3556 T1b [74.7%], diseases). The median follow-up period was 9.2 years. The 9-year cumulative incidence of distant metastasis was 1.5% with ET and 2.6% without ET (adjusted subdistribution hazard ratio [sHR], 0.54; 95% CI, 0.32-0.93). In multivariate analysis, the independent risk factors for distant metastasis were no history of ET, mastectomy, high-grade, and lymphatic invasion. The 9-year overall survival was 97.0% and 94.4% with and without ET, respectively (adjusted HR, 0.57; 95% CI, 0.39-0.83). In addition, adjuvant ET reduced the incidence of ipsilateral and contralateral breast cancer (9-year rates; 1.1% vs. 6.9%; sHR, 0.17, and 1.9% vs. 5.2%; sHR, 0.33). CONCLUSIONS: The prognosis was favorable in patients with ER-positive and HER2-negative T1a/bN0M0 breast cancer. Furthermore, adjuvant ET reduced the incidence of distant metastasis with minimal absolute risk difference. These findings support considering the omission of adjuvant ET, especially for patients with low-grade and no lymphatic invasion disease.

Metastasis-directed therapy for oligometastases in breast cancer.

The concept of oligometastases was first proposed to describe a disease state between localized cancer and extensive metastasis. After the emergence of variations in the definition of oligometastasis, in April 2020 the European Society for Radiotherapy and Oncology and the European Organization for Research and Treatment of Cancer defined oligometastases as the presence of one to five metastatic lesions that can be safely treated. However, the pathogenesis of oligometastases remains unknown, and it is uncertain which patients will benefit from metastasis-directed therapy. Breast cancer with oligometastases is generally managed with systemic therapy. Retrospective studies have suggested that the addition of metastasis-directed therapy, such as surgery, radiofrequency ablation and stereotactic body radiation therapy, may increase overall survival in breast cancer patients with oligometastases, but as yet there have been no prospective studies. Phase II trials of stereotactic body radiation therapy or fractionated irradiation for oligometastases of breast cancer have demonstrated impressive rates of local control and overall survival. Although the efficacy of stereotactic body radiation therapy in the SABR-COMET was largely anticipated, it is noteworthy that only 18% of the patient population had breast cancer. For this reason, various trials were planned or are being conducted globally to investigate the efficacy of metastasis-directed therapy for oligometastases of breast cancer. Metastasis-directed therapy for oligometastases has been shown to be effective, and stereotactic body radiation therapy and other therapies are commonly used internationally and are considered to be safe. However, the efficacy of metastasis-directed therapy for oligometastases has not yet been proven. The results of future clinical trials are thus eagerly awaited.

Clinical Utility of Breast Ultrasound Images Synthesized by a Generative Adversarial Network.

BACKGROUND AND OBJECTIVES: This study compares the clinical properties of original breast ultrasound images and those synthesized by a generative adversarial network (GAN) to assess the clinical usefulness of GAN-synthesized images. MATERIALS AND METHODS: We retrospectively collected approximately 200 breast ultrasound images for each of five representative histological tissue types (cyst, fibroadenoma, scirrhous, solid, and tubule-forming invasive ductal carcinomas) as training images. A deep convolutional GAN (DCGAN) image-generation model synthesized images of the five histological types. Two diagnostic radiologists (reader 1 with 13 years of experience and reader 2 with 7 years of experience) were given a reading test consisting of 50 synthesized and 50 original images (≥1-month interval between sets) to assign the perceived histological tissue type. The percentages of correct diagnoses were calculated, and the reader agreement was assessed using the kappa coefficient. RESULTS: The synthetic and original images were indistinguishable. The correct diagnostic rates from the synthetic images for readers 1 and 2 were 86.0% and 78.0% and from the original images were 88.0% and 78.0%, respectively. The kappa values were 0.625 and 0.650 for the synthetic and original images, respectively. The diagnoses made from the DCGAN synthetic images and original images were similar. CONCLUSION: The DCGAN-synthesized images closely resemble the original ultrasound images in clinical characteristics, suggesting their potential utility in clinical education and training, particularly for enhancing diagnostic skills in breast ultrasound imaging.

Germline variant of BRCA1 c.5332G>A has clinical features of hereditary breast and ovarian cancer syndrome.

The proband was a 39-year-old Japanese woman with stage I triple negative breast cancer. Germline BRCA1 and BRCA2 genetic testing revealed the presence of a BRCA1 c.5332G>A (p.Asp1778Asn) variant classified as a VUS in the heterozygous state. She underwent curative surgery and adjuvant chemotherapy for her TNBC, but no intensive follow-up or risk-reducing surgery was performed in contrast to normal practice in a patient with hereditary breast and ovarian cancer syndrome. At postoperative 2 years 6 months, elevation of CA15-3 led to the diagnosis of Stage III high-grade serous ovarian cancer. Studies and information in public databases at the time of the patient's genetic testing showed only VUS results for c.5332G>A; within the next few years, one pathogenic and one likely pathogenic result were confirmed. Thus, according to a joint consensus recommendation of the ACMG/AMP, c.5332G>A is considered 'likely pathogenic'. The public database should be checked regularly for VUS results, and practical management should be considered if reliable likely pathogenic or pathogenic reports were added.

Short- and long-term outcomes of immediate breast reconstruction surgery after neoadjuvant chemotherapy.

PURPOSE: Immediate breast reconstruction (IBR) is a standard option for breast cancer patients, although its utility in patients with advanced breast cancer requiring neoadjuvant chemotherapy (NAC) is debatable. We assessed the short-term complications and long-term prognosis of IBR after NAC. METHODS: We retrospectively analyzed 1135 patients with IBR and/or NAC between 2010 and 2018, 43 of whom underwent IBR after NAC. RESULTS: Twenty-five patients underwent reconstruction with a tissue expander (TE) followed by silicon breast implantation, 5 with a latissimus dorsi muscle transfer flap, and 13 with a deep inferior epigastric perforator flap. Complete surgical resection with a free margin confirmed by a pathological assessment was achieved in all patients. The evaluation of the short-term complications indicated no cases of total flap necrosis, two cases of partial flap necrosis, and one case of wound infection. Only one case required postponement of subsequent therapy due to partial flap necrosis. A long-term evaluation indicated no local recurrence, although distant metastasis was observed in 4 cases, 3 patients died, and TE removal after post-mastectomy radiotherapy (PMRT) was performed in 2 of 11 TE cases. CONCLUSION: IBR may be a viable option in patients with advanced breast cancer who achieve complete surgical resection after NAC.

Metastasis of breast cancer to liver through direct lymphatic drainage: a case report.

Breast cancer liver metastasis (BCLM) is considered to occur by hematogenous spread of primary breast cancer cells. We herein present a case of lymphatic BCLM that was confirmed by preoperative imaging for sentinel lymph node biopsy (SLNB). A woman in her early 70s was diagnosed with clinical stage T2N0M0 invasive lobular cancer of the left breast. She underwent mastectomy with SLNB. Preoperative lymphoscintigraphy showed intense accumulation of isotope in the upper abdomen, corresponding to segment IV of the liver on single-photon emission computed tomography/computed tomography (SPECT/CT). However, no abnormalities were detected on magnetic resonance imaging. At 2.5 years postoperatively, the patient's serum CA15-3 concentration was elevated, and positron emission tomography/computed tomography (PET/CT) showed a solitary liver metastasis. The PET/CT findings were similar to the SPECT/CT findings obtained 2.5 years earlier, indicating that the BCLM had developed lymphatically. To the best of our knowledge, this is the first case report of lymphatic BCLM proven by imaging examination.

Safety and Effectiveness of Areola-sparing Mastectomy for Breast Cancer With Intraductal Lesions.

BACKGROUND/AIM: Areola-sparing mastectomy (ASM), a conservative mastectomy with nipple hollowing, can be applied to intraductal breast cancer with a tumour-nipple-areola complex (NAC) distance of ≤2 cm. Here, we evaluated the safety and effectiveness of ASM. PATIENTS AND METHODS: We retrospectively reviewed the surgical outcomes of 61 patients (64 breasts) who underwent ASM between 2016 and 2020. RESULTS: Of the 64 breasts, 33 (51.6%) underwent ASM because the tumour-NAC distance on preoperative magnetic resonance imaging was ≤2 cm. Two patients had positive excisional margins but these were at the posterior areola surface therefore additional resection was possible. Over a median postoperative observation period of 16 months (range=3-52 months), one patient developed chest wall recurrence that was resected and did not recur again. CONCLUSION: For breast cancer with an extensive intraductal component, ASM is a good alternative to nipple-sparing mastectomy because it allows safe resection while maintaining aesthetics.

Clinical Usefulness of Ultrasound-Guided Fine Needle Aspiration and Core Needle Biopsy for Patients with Axillary Lymphadenopathy.

Background and Objectives: It is necessary to properly diagnose and manage axillary lymphadenopathy caused by a variety of diseases. This study aimed to evaluate the utility of ultrasound (US)-guided sampling in patients with axillary lymphadenopathy. Materials and Methods: Patients with axillary lymphadenopathy (excluding patients with newly diagnosed breast cancer) who underwent US-guided fine needle aspiration (FNA) or core needle biopsy (CNB) at a single center between February 2016 and September 2020 were retrospectively examined. The association between US imaging findings and malignancy was investigated and the diagnostic performance of US-guided sampling was assessed. Results: Fifty-five patients (including eight males) were included in the study; of these, 34 patients (61.8%) were finally diagnosed with a malignant lymph node lesion. Twenty-two patients (40.0%) had undergone FNA and 33 (60.0%) had undergone CNB. Larger short and long axis diameters, thicker lymph node cortex, and the absence of fatty hilum on the US were significantly associated with malignancy (p < 0.05). The diagnostic performance of FNA, CNB, and FNA + CNB was excellent (sensitivity, specificity, and accuracy of 0.909, 0.900, and 0.917 for FNA, 0.958, 1.000, and 0.970 for CNB, and 0.941, 0.952, and 0.945 for FNA + CNB, respectively). Conclusions: US-guided FNA and CNB play an important role in the diagnosis and management of patients with axillary lymphadenopathy.

Association between skin flap necrosis and sarcopenia in patients who underwent total mastectomy.

BACKGROUND: Sarcopenia is associated with postoperative complications in patients undergoing digestive surgery. In this study, we investigated the impact of preoperative sarcopenia on postoperative complications in breast cancer patients who underwent total mastectomy. METHODS: Patients with breast cancer who underwent total mastectomy were included in the analysis. The relationship between the presence of sarcopenia and postoperative complications (e.g., skin flap necrosis and seroma) and between the incidence of these complications as well as preoperative and surgical factors was investigated. Moreover, the effects of sarcopenia on recurrence-free survival and overall survival were evaluated. The psoas muscle index calculated using values measured on preoperative computed tomography images was used to diagnose sarcopenia. RESULTS: In total, 43 (49%) of 88 patients presented with sarcopenia. The number of patients with a Geriatric Nutritional Risk Index score <91 was higher in the sarcopenia group than in the non-sarcopenia group (p = 0.011). Seroma was observed in 32 (36.4%) patients, and no significant difference was observed between the patients with and without sarcopenia (16 [35.6%] in the non-sarcopenia group vs 16 [37.2%] in the sarcopenia group). By contrast, skin flap necrosis was observed in 20 (22.7%) patients, and the number of patients with this complication was higher in the sarcopenia group than in the non-sarcopenia group (15 [34.9%] vs 5 [11.1%]). CONCLUSION: Sarcopenia is a risk factor for skin flap necrosis and may be an important factor for preoperative evaluation in patients who will undergo total mastectomy.

A Case of Adenomyoepithelioma With a Pleomorphic Adenoma-Like Component of the Male Breast.

Adenomyoepithelioma (AME) of the male breast is a rare tumor characterized by biphasic proliferation of gland epithelial cells and myoepithelial cells. Though pleomorphic adenoma (PA) is also known to be an epithelial-myoepithelial tumor in the breast, and these tumors are considered to exist on the same spectrum by some authors, to the best of our knowledge, there have been no reports of a clear transition from AME to PA in the male breast. Therefore, the case of an 85-year-old man with AME with PA-like components is presented.

[A Case Report on the Effectiveness of Olaparib in a Patient with Recurrent Breast Cancer with Human Immunodeficiency Virus Infection].

A 43 -year-old woman presented to the hospital with a right breast tumor. She had been treated for human immunodeficiency virus(HIV)infection for 5 years. After being diagnosed with right breast cancer, she underwent total mastectomy and sentinel lymph node biopsy, which indicated T2N1M0 triple-negative breast cancer. She received doxorubicin and cyclophosphamide( AC)followed by docetaxel(AC-T)as postoperative adjuvant chemotherapy. However, 14 months after the adjuvant chemotherapy finished, distant metastasis occurred in the brain, lung, and mediastinum lymph nodes. Treatment for relapse was initiated, with whole brain radiotherapy followed by paclitaxel plus bevacizumab combination therapy(PB); however, new metastatic lesions were found in the bone, liver, and mediastinum lymph node after 2 courses of PB. Given the risk of hereditary breast and ovarian cancer syndrome, a BRCAgene test was performed when the patient received radiotherapy for left recurrent laryngeal nerve paralysis caused by mediastinal lymph nodes; this showed a result positive for a deleterious mutation in BRCA1. Thus, treatment with olaparib, a poly(ADP-ribose)polymerase(PARP)inhibitor, was started. Metastatic lesions, including barky growth, in the liver metastasis were well controlled, as confirmed by CT imaging 4 months after the start of olaparib.

Predictors for upstaging of ductal carcinoma in situ (DCIS) to invasive carcinoma in non-mass-type DCIS.

Preoperatively diagnosed ductal carcinoma in situ (DCIS) is sometimes upstaged to invasive cancer by postoperative pathological examination. Various preoperative factors associated with upstaging to invasive cancer have been reported; however, this subject remains to be clarified. DCIS takes various forms on imaging, but many cases show non-mass-type lesions. In non-mass-type DCIS, recognizing the presence of invasion is difficult. To investigate predictors associated with upstaging to invasive cancer more precisely, we examined only non-mass-type DCIS. The present study retrospectively analyzed 101 patients diagnosed with non-mass-type DCIS preoperatively on breast biopsy at our institution between 2007 and 2017. Data were analyzed using Fisher's exact probability test and two-sample t-tests. Multivariate analysis was performed using logistic regression. The results showed that 27 patients (27%) were finally diagnosed with invasive cancer. Univariate analysis revealed abnormal result of palpation on breast examination (P=0.05), comedo necrosis (P=0.05), and HER2 status (P=0.02) as significant predictors. Multivariate analysis revealed an abnormal result of palpation as an independent predictor of invasive cancer underestimation (odds ratio 4.76; confidence interval 1.44-15.7; P=0.01). In conclusion, preoperatively diagnosed non-mass-type DCIS represented an underestimation in approximately 27% of cases. In particular, the presence of a clinically abnormal palpation increases the chance of upstaging to invasive cancer.

Predictive factors of an axillary pathological complete response of node-positive breast cancer to neoadjuvant chemotherapy.

PURPOSE: The present study aimed to identify the predictive factors of an axillary pathological complete response (Ax-pCR) in patients with node-positive breast cancer who underwent neoadjuvant chemotherapy (NAC). METHODS: The present study included 219 patients who underwent NAC followed by curative surgery, including axillary lymph node dissection (ALND), for 221 breast cancers between January 2010 and April 2018. All patients were clinically and/or pathologically confirmed to be node-positive at the initial diagnosis. The predictive factors of Ax-pCR were analyzed using a chi-square test and multivariate logistic regression models. RESULTS: Ninety-five patients (43%) achieved Ax-pCR after NAC. The odds of achieving Ax-pCR were significantly improved when tumors were high grade (odds ratio [OR] 2.20, 95% confidence interval [CI] 1.00-4.84), estrogen receptor (ER) negative (OR 2.65 95% CI 1.23-5.70), ycN0 on ultrasound (US) imaging (OR 3.89, 95% CI 1.90-7.97), and showed a clinical complete response (CR) at the primary site after NAC (OR 4.22, 95% CI 1.59-11.27). CONCLUSIONS: Ax-pCR was more likely to be achieved in patients who were diagnosed with ER-negative and high-grade breast cancer and those with ycN0 and clinical CR at the primary site after NAC than among others. Among these patients, those with initially cN1/N2 might be good candidates for a deescalated treatment strategy after NAC.

[Toxicity of Palbociclib in Patients Aged 70 Years and Older with Metastatic Breast Cancer].

We aimed to examine palbociclib toxicity in patients aged 70 years and older with metastatic breast cancer(MBC). From December 2017 to August 2018, 32 patients with estrogen receptor(ER)-positive, human epidermal growth factor receptor 2(HER2)-negative MBC were included in this study. The most common adverse event(AE)observed was neutropenia, and comparative rates of grade 3 or 4 AE were identified in the groups of patients aged ≥70 years(n=11)and <70 years(n=21) (91% vs 81%). Febrile neutropenia occurred in one patient. Although dose interruption rate was higher in the older group (≥70 years of age)than in the younger group(<70 years of age)(100% vs 86%, respectively), reduction rates were similar between the two groups(64% vs 62%, respectively). Palbociclib was well-tolerated in Japanese older(≥70 years of age) MBC patients.

Simultaneous comparison between strain and shear wave elastography of breast masses for the differentiation of benign and malignant lesions by qualitative and quantitative assessments.

PURPOSE: To compare the addition of diagnostic strain elastography (SE) and shear wave elastography (SWE) values to the conventional B-mode ultrasonography in differentiating between benign and malignant breast masses by qualitative and quantitative assessments. MATERIALS AND METHODS: B-mode ultrasound, SE, and SWE were simultaneously performed using one ultrasound system in 148 breast masses; 88 of them were malignant. The breast imaging reporting and data system category in the B-mode, Tsukuba score (SETsu), Fat-Lesion-Ratio (SEFLR) in SE, and five-point color assessment (SWEcol) and elasticity values (SWEela) in SWE were assessed. The results were compared using the area under the receiver-operating characteristic curve (AUC). RESULT: The AUC for B-mode and each elastography were similar (B-mode, 0.889; SETsu, 0.885; SEFLR, 0.875; SWEcol, 0.881; SWEela, 0.885; P > 0.05). The combined sets between B-mode and either of the elastography technique showed good diagnostic performance (B-mode + SETsu, 0.903; B-mode + SEFLR, 0.909; B-mode + SWEcol, 0.919; B-mode + SWEela, 0.914). B-mode + SWEcol and B-mode + SWEela showed a higher AUC than B-mode alone (P = 0.026 and 0.029), and B-mode + SETsu and B-mode + SEFLR showed comparable AUC to B-mode alone (P = 0.196 and 0.085). There was no significant difference between qualitative and quantitative assessments for the combined sets of B-mode and elastography (P > 0.05). CONCLUSION: The addition of both SE and SWE to B-mode ultrasound improved the diagnostic performance with increased AUC, and especially SWE was more useful than SE, and no significant difference was found between qualitative and quantitative assessments.

Ultrasound-guided fine-needle aspiration of axillary lymph nodes in breast cancer: Diagnostic accuracy and role in surgical management.

BACKGROUND: The objective of this study was to evaluate the accuracy of fine needle aspiration cytology (FNAC) of axillary lymph nodes (LN) in breast cancer, to compare the results of FNAC and pathological examination, and to distinguish patients with 1 to 2 metastatic LNs from those with ≥3 metastatic LNs in patients with FNAC-positive patients. PATIENTS AND METHODS: This study included 198 breasts of 196 patients with breast cancer who underwent FNAC and surgery for the primary and axilla without neoadjuvant chemotherapy from January 2010 to August 2016. Axillary nodal status was assessed by ultrasound (US), and whether FNAC-positive had three or more suspicious LNs on US imaging was examined. RESULTS: The results of FNAC were positive in 75 (38%), negative in 97 (49%), suspicious in 2 (1%), indeterminate in 5 (2.5%), and insufficient in 19 patients (9.5%). FNAC sensitivity, specificity, positive predictive value, and negative predictive value were 62.6%, 100%, 100%, and 62.0%, respectively. Whereas 53% (18/34) of patients with false-negative FNAC had one metastatic LN on final pathology, 61% (47/77) patients who were FNAC-positive had three or more metastatic LNs. In the FNAC-positive patients, all patients had ≥3 metastatic LNs if they had ≥3 suspicious LNs on US imaging. CONCLUSION: Patients with positive cytology were more likely to have ≥3 positive LNs compared to false-negative cytology patients. Patients with ≥3 abnormal LNs on US and positive FNAC might require axillary dissection.

Distinction between benign and malignant breast masses at breast ultrasound using deep learning method with convolutional neural network.

PURPOSE: We aimed to use deep learning with convolutional neural network (CNN) to discriminate between benign and malignant breast mass images from ultrasound. MATERIALS AND METHODS: We retrospectively gathered 480 images of 96 benign masses and 467 images of 144 malignant masses for training data. Deep learning model was constructed using CNN architecture GoogLeNet and analyzed test data: 48 benign masses, 72 malignant masses. Three radiologists interpreted these test data. Sensitivity, specificity, accuracy, and area under the receiver operating characteristic curve (AUC) were calculated. RESULTS: The CNN model and radiologists had a sensitivity of 0.958 and 0.583-0.917, specificity of 0.925 and 0.604-0.771, and accuracy of 0.925 and 0.658-0.792, respectively. The CNN model had equal or better diagnostic performance compared to radiologists (AUC = 0.913 and 0.728-0.845, p = 0.01-0.14). CONCLUSION: Deep learning with CNN shows high diagnostic performance to discriminate between benign and malignant breast masses on ultrasound.

The feasibility of using 18F-FDG-PET/CT in patients with mucinous breast carcinoma.

PURPOSE: This study investigated the correlation between fluorine-18-fluorodeoxyglucose (F-FDG)-PET/computed tomography (CT) and clinicopathological factors in patients with mucinous breast carcinoma and assessed the feasibility of using F-FDG-PET/CT in evaluating tumors. PATIENTS AND METHODS: We retrospectively examined 42 consecutive patients with pathologically proven mucinous breast carcinoma who preoperatively underwent F-FDG-PET/CT. In addition, we compared F-FDG uptake with clinicopathological characteristics. RESULTS: F-FDG uptake was observed in 39 (92.9%) lesions. The maximum standardized uptake value (SUVmax) (mean±SD) of all mucinous carcinoma, pure type, and mixed type was 2.3±1.3 (range: 1.0-5.1), 1.9±0.9 (range: 1.0-3.5), and 3.2±1.3 (range: 1.4-5.1), respectively. The mixed type had a significantly higher F-FDG uptake than the pure type (P=0.006). In addition, the sensitivity, specificity, accuracy, and area under the curve for distinguishing the pure type from the mixed type were 61.5, 89.7, 81.0, and 0.76, respectively (cutoff value: SUVmax>3.0). Furthermore, SUVmax correlated significantly with the high nuclear grade (P=0.010) and the presence of axillary lymph node metastasis (P=0.017). CONCLUSION: F-FDG uptake efficiently distinguishes the pure type from the mixed type and may play a potential role in predicting the aggressiveness of mucinous breast carcinoma.

[A Case of HER2 Positive Occult Breast Cancer Presenting as Swollen Axillary Lymph Nodes].

Occult breast cancer, which develops as a metastatic lesion with no primary tumor detected in the breast, is a rare breast cancer. A 68-year-old female patient particularly complained of the presence of a right axillary mass. The mass in the right axilla was palpable, but no tumor was found in both the breasts on palpation, ultrasound examination, or MRI. Partial breast resection and axillary lymph node dissection were performed following a diagnosis of invasive ductal carcinoma by core needle biopsy. There was no mammary gland tissue present around the tumor due to the pathology of the disease, and the tumor was diagnosed as occult breast cancer. As the cancer was ER negative and HER2 positive, treatment with a combination of FEC, docetaxel, and trastuzumab was initiated. Radiotherapy, which irradiated the right supraclavicular fossa and the right mammary gland, was administered. No disease recurrence and mammary tumor has been reported in the patient till date. Treatment of occult breast cancer generally includes local therapy such as radiation and surgery. However, in the present case, we did not operate upon the breast; instead we treated the right breast and the right supraclavicular fossa with radiation therapy. As the tumor was HER2 positive, we reasoned that local control of disease would be likely if treatment with chemotherapy and trastuzumab was performed effectively.