Clinicopathologic features and genomic profiling of female axillary lymph node metastases from adenocarcinoma or poorly differentiated carcinoma of unknown primary.

PURPOSE: Axillary lymph node metastases from adenocarcinoma or poorly differentiated carcinoma of unknown primary (CUPAx) is a rare disease in women. This retrospective study intended to examine the clinicopathological features of CUPAx and compared CUPAx genetically with axillary lymph node metastases from breast cancer (BCAx), investigating differences in their biological behavior. METHODS: We conducted the clinical and prognostic analysis of 58 CUPAx patients in West China Hospital spanning from 2009 to 2021. Gemonic profiling of 12 CUPAx patients and 16 BCAx patients was conducted by the FoundationOne CDx (F1CDx) platform. Moreover, we also compared the gene mutation spectrum and relevant pathways between the two groups and both TCGA and COSMIC databases. RESULTS: The majority of the 58 CUPAx patients were HR-/HER2- subtype. Most patients received mastectomy combined radiotherapy (50 Gy/25f). CUPAx patients who received mastectomy instead of breast-conserving surgery had a more favorable overall prognosis. Radiotherapy in chest wall/breast and supraclavicular/infraclavicular fossa was the independent prognostic factor (HR = 0.05, 95%CI = 0.00-0.93, P = 0.04). In 28 sequencing samples (CUPAx, n = 12, BCAx, n = 16) and 401 TCGA-BRCA patients, IRS2 only mutated in CUPAx (33.33%) but amplified in BCAx (11.11%) and TCGA-BRCA (1.5%). Pathway analysis revealed that BCAx had more NOTCH pathway mutations than CUPAx. Enrichment analysis showed that CUPAx enriched more in mammary development and PML bodies than BCAx, but less in the positive regulation of kinase activity. CONCLUSIONS: More active treatment methods, like chemotherapy, mastectomy and postoperative radiotherapy, could improve the prognosis of CUPAx. The differential mutation genes of CUPAx and BCAx might be associated with their respective biological behaviors like invasiveness and prognosis.

Occult Breast Cancer Presenting as Sternum Pain.

Bone metastasis has been reported in up to 70% of patients with advanced breast cancer. A total of 55.76% of skeletal metastases in women were derived from breast cancer. However, patients with bone metastasis from an occult primary breast cancer are a rare subset of patients. Here, we present the case of a 38-year-old woman who had sternum pain for 4 months. A whole-body PET-CT scan revealed that the FDG uptake of both the sternum and internal mammary node was significantly increased. The final diagnosis of occult breast cancer was established by immunohistochemical (IHC) staining, which is of great significance for identifying the origin of a metastatic tumor despite no visualized lesions of mammary glands.

Clinicopathological features, psychological status, and prognosis of 33 patients with occult breast cancer.

BACKGROUND: Occult breast cancer (OBC) has traditionally been considered to be a carcinoma of unknown primary origin with a favorable prognosis and can be treated as stage II-III breast cancer. Due to the small number of cases and limited clinical ex-perience, treatments vary greatly around the world and no standardized treat-ment has yet been established. AIM: To investigate the clinicopathological features, psychological status and prog-nostic features of patients with OBC. METHODS: The clinicopathological data of 33 OBC patients diagnosed and treated in the Affiliated Hospital of Xuzhou Medical University and Xuzhou Central Hospital from November 2015 to November 2022 were retrospectively analyzed. The psychological status of OBC patients was evaluated by the Self-rating Anxiety Scale and Self-rating Depression Scale. Patients' emotions, stress perception and psychological resilience were evaluated by the Positive and Negative Affect Schedule, the Chinese Perceived Stress Scale, and the Connor-Davidson Resilience Scale (CD-RISC), respectively. Patient survival was calculated using the Kaplan-Meier method, and survival curves were plotted for analysis with the log-rank test. Univariate and multivariate survival analyses were performed using the Cox regression model. RESULTS: The 33 OBC patients included 32 females and 1 male. Of the 33 patients, 30 (91%) had axillary tumors, 3 (9%) had a neck mass as the primary symptom; 18 (54.5%) had estrogen receptor-positive tumors, 17 (51.5%) had progesterone receptor-positive tumors, and 18 (54.5%) had Her-2-positive tumors; 24 (72.7%) received surgical treatment, including 18 patients who underwent modified radical mastectomy, 1 patient who underwent breast-conserving surgery plus axillary lymph node dissection (ALND), and 5 patients who underwent ALND alone; 12 patients received preoperative neoadjuvant therapy. All 30 patients developed anxiety and depression, with low positive affect scores and high negative affect scores, accompanied by a high stress level and poor psychological resilience. There were no differences in the psychological status of patients according to age, body mass index, or menopausal status. The overall survival and disease-free survival (DFS) of all the patients were 83.3% and 55.7%, respectively. Univariate analysis demonstrated that the initial tumor site (P = 0.021) and node stage (P = 0.020) were factors that may affect patient prognosis. The 5-year DFS rate of OBC patients who received radiotherapy was greater (P < 0.001), while the use of different surgical methods (P = 0.687) had no statistically significant effect on patient outcomes. Multivariate analysis revealed that radiotherapy (P = 0.031) was an independent prognostic factor. Receiving radiotherapy had a significant effect on the CD-RISC score (P = 0.02). CONCLUSION: OBC is a rare breast disease whose diagnosis and treatment are currently controversial. There was no significant difference in the efficacy of other less invasive surgical procedures compared to those of modified radical mastectomy. In addition, radiotherapy can significantly improve patient outcomes. We should pay attention to the psychological state of patients while they receive antitumor therapy.

Management of Male Patients With Occult Breast Cancer: Analysis of the National Cancer Database.

INTRODUCTION: Occult breast cancer (OBC) consists of <0.1% of breast cancer cases in the United States. Male occult breast cancer (mOBC) has not been well-studied outside of case reports, and management is largely based on female OBC (fOBC) studies. We aim to examine the prevalence of mOBC among those in the National Cancer Database with breast cancer and describe treatment modalities received by mOBC compared to fOBC. METHODS: The National Cancer Database was queried for patients with OBC from 2004 to 2018. Chi-Square test and Fisher's exact tests compared patient, clinical, and facility characteristics by sex. Treatment modalities [systemic therapy, radiation therapy, axillary lymph node dissection, modified radical mastectomy (MRM)] were compared. A subgroup analysis examined pathologic upstaging in patients who underwent MRM. RESULTS: Of 23,374 male patients with breast cancer, 0.13% were identified to have mOBC [versus 0.09% in fOBC]. cN2/N3 disease was significantly more prevalent in the mOBC cohort (61.3%) than in the fOBC cohort (30.7%, P < 0.001). Receipt of axillary lymph node dissection or MRM was not significantly different by sex. Male OBC (mOBC) patients were less likely to receive trimodality treatment than fOBC patients. In patients who underwent MRM, more mOBC patients [75%] were pathologically upstaged as T+ after mastectomy than fOBC patients [30%, P < 0.001], questioning the adequacy of diagnostic workup for mOBC compared to fOBC. CONCLUSIONS: This review confirms mOBC as an extremely rare disease. Multimodal treatments have been highly utilized to optimize care in this patient population. Further investigation is warranted to examine the survival benefit of treatment regimens for mOBC.

Occult breast cancer patients with mastectomy have better prognosis than those with breast-conserving therapy.

Background: This single-center retrospective study compared the efficacy of breast-conserving therapy along with axillary lymph node dissection (ALND) with mastectomy and ALND with regard to survival of Chinese patients with occult breast cancer. Materials & methods: Univariate Kaplan-Meier analysis and multivariate Cox proportional hazards model were used to compare treatments and prognosis. Results: A total of 111 patients with a median follow-up of 72.9 months were included. 39 patients with mastectomy + ALND had better disease-free survival than 72 patients with breast-conserving therapy + ALND (HR = 0.31; p = 0.012). Patients with radiotherapy demonstrated inferior survival for both overall survival (HR = 2.67; p = 0.071) and disease-free survival (HR = 5.35; p = 0.002). Surgical strategies and radiotherapy remained significantly predictive of better disease-free survival in multivariate analyses. Conclusion: Mastectomy and ALND demonstrate superior disease-free prognosis compared with breast-conserving therapy and ALND in occult breast cancer.

Impact of GAN artifacts for simulating mammograms on identifying mammographically occult cancer.

Purpose: Generative adversarial networks (GANs) can synthesize various feasible-looking images. We showed that a GAN, specifically a conditional GAN (CGAN), can simulate breast mammograms with normal, healthy appearances and can help detect mammographically-occult (MO) cancer. However, similar to other GANs, CGANs can suffer from various artifacts, e.g., checkerboard artifacts, that may impact the quality of the final synthesized image, as well as the performance of detecting MO cancer. We explored the types of GAN artifacts that exist in mammogram simulations and their effect on MO cancer detection. Approach: We first trained a CGAN using digital mammograms (FFDMs) of 1366 women with normal/healthy breasts. Then, we tested the trained CGAN on an independent MO cancer dataset with 333 women with dense breasts (97 MO cancers). We trained a convolutional neural network (CNN) on the MO cancer dataset, in which real and simulated mammograms were fused, to identify women with MO cancer. Then, a radiologist who was independent of the development of the CGAN algorithms evaluated the entire MO cancer dataset to identify and annotate artifacts in the simulated mammograms. Results: We found four artifact types, including checkerboard, breast boundary, nipple-areola complex, and black spots around calcification artifacts, with an overall incidence rate over 69% (the individual incident rate ranged from 9% to 53%) from both normal and MO cancer samples. We then evaluated their potential impact on MO cancer detection. Even though various artifacts existed in the simulated mammogram, we found that it still provided complementary information for MO cancer detection when it was combined with the real mammograms. Conclusions: We found that artifacts were pervasive in the CGAN-simulated mammograms. However, they did not negatively affect our MO cancer detection algorithm; the simulated mammograms still provided complementary information for MO cancer detection when combined with real mammograms.

Occult breast cancer with pleural metastasis.

Carcinoma of unknown primary (CUP) is defined as histologically confirmed metastases from an undetectable malignant primary site. A subgroup of CUP, known as occult breast cancer (OBC), is a biopsy-proven metastatic breast cancer without an original breast tumor. It remains a diagnostic and therapeutic enigma as there is no consensus on the diagnostic and treatment approaches for the patients with OBC. This case report is a unique presentation of OBC, emphasizing the importance of identifying OBC patients in the early stages. A dedicated team of experts and a more definitive approach to diagnosis and treatment of OBC are essential to prevent delays in the whole process.

Adenocarcinoma of the Breast Presenting as Occult Breast Cancer With Axillary and Supraclavicular Lymph Node Metastasis: A Case Report.

Breast cancer is a leading cause of cancer-related mortality in women, with over 250,000 new cases diagnosed annually in the United States. Although mortality rates have decreased, breast cancer remains the second most common cause of cancer death in women. Occult breast cancer (OBC), a rare form of breath cancer that typically presents as axillary lymphadenopathy with no evidence of primary disease, accounts for less than 1% of all breath cancer diagnoses. To date, only three cases of OBC treated with radical mastectomy have been documented in the literature. This case presents a 76-year-old female with a benign left breast mass who was subsequently diagnosed with metastatic estrogen receptor/progesterone receptor (ER/PR)-positive ductal cell breast carcinoma after a visible axillary lymph node was detected on follow-up imaging. Due to the rarity of OBC, standardized treatment guidelines have not been established. Our patient underwent a left radical mastectomy with axillary and cervical lymph node dissection. Clinicians should maintain a high index of suspicion for biopsying axillary lymph nodes in females without evidence of breast malignancy, even though OBC has a low incidence rate. This case report aims to present a documented case of OBC and comprehensibly review the existing literature, discussing the available diagnostic and treatment approaches for this condition. We describe the case of a 76-year-old woman referred to surgery consultation due to a mammographic finding of a left superior lateral mass. The mass was biopsied and found to have no malignancy. On follow-up imaging, she was found to have a left axillary lymph node visible. Her only complaints at this time were breast tenderness and swelling. She underwent fine needle aspiration of the mass, which showed atypical cells that led to an excisional biopsy of the detected axillary node. The biopsy pathology report showed ER/PR-positive ductal cell breast carcinoma. The patient underwent left modified radical mastectomy with left axillary and cervical lymph node dissection. It was during this procedure that the pathology report revealed a 2 cm lesion on the left breast that showed ER/PR-positive infiltrating ductal carcinoma with 32 out of the 37 lymph nodes positive for metastatic disease. This case illustrates the importance of having a low imaging threshold in patients with vague breast symptoms. Surgeons should have a high level of suspicion when metastatic breast cancer is found, even if there is no clinical or radiographic evidence of a primary lesion. This includes conducting lymph node biopsies in patients who present with lymphadenopathy without the initial presence of primary breast cancer. Many studies agree that a modified radical mastectomy with lymph node recession is the treatment of choice for metastatic breast cancer without evidence of primary lesion. However, the efficacy of adjuvant treatments like radiation therapy or chemotherapy should be further studied.

Infiltrating metastatic ductal carcinoma initially presenting as axillary lymph node metastases diagnosed with PET/CT and MRI: case report and brief review of occult breast carcinoma.

INTRODUCTION: The concept of occult breast carcinoma (OBC) was first described in 1907 by Halsted, who described this type of breast cancer to arise from small, undetectable tumours in the breast that had already metastasized to the lymph nodes. Although the breast is the most likely site for the primary tumour, non-palpable breast cancer presenting as an axillary metastasis has been reported, but with a low frequency of less than 0.5% of all breast cancers. OBC represents a complex diagnostic and therapeutic dilemma. Considering its rarity, clinicopathological information is still limited. CASE REPORT: A 44-year-old patient presented to the emergency room with an extensive axillary mass as the first manifestation. Conventional evaluation of the breast with mammography and ultrasound was unremarkable. However, a breast MRI confirmed the presence of conglomerate axillary nodes. A supplementary whole-body PET-CT established the axillary conglomerate with a malignant behaviour with SUVmax of 19.3. The primary tumour was not detected in the breast tissue of the patient, confirming the diagnosis of OBC. Immunohistochemical results showed negative receptors for estrogen and progesterone. CONCLUSION: Although OBC is a rare diagnosis, its existence is a possibility in a patient with breast cancer. Mammography and breast ultrasound with unremarkable findings but with high clinical suspicion should be supplemented with additional imaging methods, such as MRI and PET-CT, emphasizing the appropriate pre-treatment evaluation.

Prognostic Models Using Machine Learning Algorithms and Treatment Outcomes of Occult Breast Cancer Patients.

BACKGROUND: Occult breast cancer (OBC) is an uncommon malignant tumor and the prognosis and treatment of OBC remain controversial. Currently, there exists no accurate prognostic clinical model for OBC, and the treatment outcomes of chemotherapy and surgery in its different molecular subtypes are still unknown. METHODS: The SEER database provided the data used for this study's analysis (2010-2019). To identify the prognostic variables for patients with ODC, we conducted Cox regression analysis and constructed prognostic models using six machine learning algorithms to predict overall survival (OS) of OBC patients. A series of validation methods, including calibration curve and area under the curve (AUC value) of receiver operating characteristic curve (ROC) were employed to validate the accuracy and reliability of the logistic regression (LR) models. The effectiveness of clinical application of the predictive models was validated using decision curve analysis (DCA). We also investigated the role of chemotherapy and surgery in OBC patients with different molecular subtypes, with the help of K-M survival analysis as well as propensity score matching, and these results were further validated by subgroup Cox analysis. RESULTS: The LR models performed best, with high precision and applicability, and they were proved to predict the OS of OBC patients in the most accurate manner (test set: 1-year AUC = 0.851, 3-year AUC = 0.790 and 5-year survival AUC = 0.824). Interestingly, we found that the N1 and N2 stage OBC patients had more favorable prognosis than N0 stage patients, but the N3 stage was similar to the N0 stage (OS: N0 vs. N1, HR = 0.6602, 95%CI 0.4568-0.9542, p < 0.05; N0 vs. N2, HR = 0.4716, 95%CI 0.2351-0.9464, p < 0.05; N0 vs. N3, HR = 0.96, 95%CI 0.6176-1.5844, p = 0.96). Patients aged >80 and distant metastases were also independent prognostic factors for OBC. In terms of treatment, our multivariate Cox regression analysis discovered that surgery and radiotherapy were both independent protective variables for OBC patients, but chemotherapy was not. We also found that chemotherapy significantly improved both OS and breast cancer-specific survival (BCSS) only in the HR-/HER2+ molecular subtype (OS: HR = 0.15, 95%CI 0.037-0.57, p < 0.01; BCSS: HR = 0.027, 95%CI 0.027-0.81, p < 0.05). However, surgery could help only the HR-/HER2+ and HR+/HER2- subtypes improve prognosis. CONCLUSIONS: We analyzed the clinical features and prognostic factors of OBC patients; meanwhile, machine learning prognostic models with high precision and applicability were constructed to predict their overall survival. The treatment results in different molecular subtypes suggested that primary surgery might improve the survival of HR+/HER2- and HR-/HER2+ subtypes, however, only the HR-/HER2+ subtype could benefit from chemotherapy. The necessity of surgery and chemotherapy needs to be carefully considered for OBC patients with other subtypes.

Best treatment options for occult breast cancer: A meta-analysis.

Objectives: Occult breast cancer (OBC) is a rare malignant breast tumor. Because of the rare cases and limited clinical experience, a huge therapeutic difference has existed all over the world and standardized treatments have yet been established. Methods: A meta-analysis was conducted using MEDLINE and Embase databases to identify the choice of OBC surgical procedures in all studies: (1) patients undergoing axillary lymph node dissection (ALND) or sentinel lymph node biopsy (SLNB) only; (2) patients undergoing ALND with radiotherapy (RT); (3) patients undergoing ALND with breast surgery (BS); (4) patients undergoing ALND with RT and BS; and (5) patients undergoing observation or RT only. The primary endpoints were mortality rates, the second endpoints were distant metastasis and locoregional recurrence. Results: Among the 3,476 patients, 493 (14.2%) undergo ALND or SLNB only; 632 (18.2%) undergo ALND with RT; 1483 (42.7%) undergo ALND with BS; 467 (13.4%) undergo ALND RT and BS, and 401 (11.5%) undergo observation or RT only. After comparing the multiple groups, both groups 1 and 3 have higher mortality rates than group 4 (30.7% vs. 18.6%, p < 0.0001; 25.1% vs. 18.6%, p = 0.007), and group 1 has higher mortality rates than groups 2 and 3 (30.7% vs.14.7%, p < 0.00001; 30.7 vs. 19.4%, p < 0.0001). Group (1 + 3) had a prognosis advantage over group 5 (21.4% vs. 31.0%, p < 0.00001). There was no significant difference both in the distant recurrence rates and locoregional rates between group (1 + 3) and group (2 + 4) (21.0% vs. 9.7%, p = 0.06; 12.3% vs. 6.5%, p = 0.26). Conclusion: On the basis of this meta-analysis, our study indicates that BS including modified radical mastectomy (MRM) and breast-conserving surgery (BCS) combined RT may appear as the optimal surgical approach in patients with OBC. RT cannot prolong both the time of distant metastasis and the local recurrences.

Case report: Uncommon multiple metastases from occult breast cancer revealed by 68Ga-DOTATATE PET/CT.

Occult breast cancer is an uncommon type of breast cancer and its diagnosis is challenging. It is usually invisible on multiple imaging examines. Metastases to the rectum and inguinal lymph nodes from occult breast lobular cancer are even rarer. 68Ga-DOTA peptides can image neuroendocrine tumors by targeting specific somatostatin receptors. Besides, other tumors, including breast cancer, have been shown to express somatostatin receptors. In this case, we presented a 63-year-old woman who underwent both 18F-FDG and 68Ga-DOTATATE PET/CT due to a rectal polyp. An endoscopic excision biopsy confirmed metastatic carcinoma of suspected breast origin, but subsequent ultrasound and MRI showed no signs of malignancy in the breast and adnexa uteri. PET/CT showed obvious 68Ga-DOTATATE activity in bilateral axillary and right inguinal lymph nodes with mild 18F-FDG uptake. Final histopathology at the left axillary, right inguinal lymph nodes, and rectum indicated metastases from breast cancer while the origin remained radiologically occult. Additionally, one uterine fibroids was found with positive uptake of 68Ga-DOTATATE and negative uptake of 18F-FDG. This case suggested that 68Ga-DOTATAE PET/CT may be an effective supplement in diagnosing OBC lymph node metastases with mild 18F-FDG uptake, and it may provide a new technology for the clinical diagnosis of occult breast cancer.

The utility of ultrasound-guided tru-cut biopsy in the diagnosis of occult breast carcinoma presenting as ovarian malignancy with multiple metastases: A case of unknown primary

@#This paper documents the utility of ultrasound-guided tru-cut biopsy in the diagnosis and subsequent management of a case of occult breast carcinoma presenting with multiple distant metastases in the absence of a primary breast lesion. She was initially diagnosed as primary ovarian malignancy with metastatic disease and subsequently underwent transvaginal ultrasound-guided tru-cut biopsy of the right ovarian mass. Histologic and immunohistochemical studies were consistent with a metastatic adenocarcinoma of breast origin. The patient underwent chemotherapy for primary breast carcinoma and has responded well.

Prognostic Factors and a Model for Occult Breast Cancer: A Population-Based Cohort Study.

Occult breast cancer (OBC) is a special type of breast cancer of an unknown primary origin. Early stage OBC is treated as stage II−III breast cancer. Currently, there are no models for predicting the survival outcomes. Hence, we aimed to evaluate the role of the positive lymph node ratio (PLNR) in OBC and further establish and validate a prognostic nomogram. Patients with stage T0N+M0 breast cancer were enrolled from the Surveillance, Epidemiology, and End Results database. Univariate and multivariate Cox analyses were used to evaluate the effects of prognostic factors on breast-cancer-specific survival (BCSS), and a nomogram was established and validated for OBC. Overall, 843 patients were included, and the 5-year BCSS rate was 92.4%. Patients with a PLNR < 0.54 had better BCSS rates than those with a PLNR ≥ 0.54. The nomogram combined clinicopathological parameters, including the PLNR, pN stage, and estrogen receptor status, and showed a higher accuracy than the TNM staging system in predicting the BCSS. The patients could be stratified into different risk groups based on their prognostic scores. Patients in the low-risk subgroup showed an improved BCSS compared those in the high-risk subgroup. In conclusion, the PLNR is an independent prognostic factor for OBC. The PLNR-based nomogram has a better predictive ability than the TNM staging system and could be of great value for the treatment of OBC and prediction of its prognosis.

Case report: Unique ultrasound feature of thyroid metastases in occult breast cancer.

Occult breast cancer is an uncommon type of breast cancer. Metastases of occult breast cancer to other tissues are rather rare. We present a rare case of thyroid metastases in a 46-year-old woman who underwent occult breast cancer. The first ultrasound (US) examination of the thyroid showed that the left lobe was enlarged but had normal thyroid function. At first, this case was misdiagnosed as thyroiditis based on the thyroid US features. However, the cytological and histological results showed that nests of the neoplastic cells were found. Further immunohistochemistry results confirmed that these neoplasms were derived from breast tissue. Analysis using the successive US scans revealed that the sizes and echo of the thyroid repeatedly changed after the radiotherapy and chemotherapy treatment. To our knowledge, this is the first reported case of occult breast carcinoma presenting with thyroid metastases. This case can easily be misdiagnosed as thyroiditis due to the metastasis area not manifesting as regular suspicious nodules or diffused punctate calcifications.

Occult breast cancer presenting as axillary lymphadenopathy - Case Report.

INTRODUCTION: Occult breast carcinoma (OBC) is a rare entity and therefore generates discussion regarding diagnosis, approach, and prognosis. This article aims to present a case of OBC and reviews some concepts discussed in the literature. PRESENTATION OF CASE: 43-year-old woman with right axillary adenopathies, without further complaints, whose biopsy shows a lymph node metastasis from invasive ductal carcinoma of the breast. Breast study, breast RMI and FDG-PET did not identify the primary tumour. As decided by a multidisciplinary team, the patient underwent neoadjuvant chemotherapy, axillary surgery, breast radiotherapy and hormone therapy. Four years after surgery, the patient has no evidence of the primary tumour and no axillary recurrence. DISCUSSION: OBC was described in 1907. Although the best therapeutic approach is widely discussed in the literature, it is consensual that as long as the existence of a primary tumour is excluded by breast MRI, the conservative approach (excision of axillary adenopathy and breast and axillary radiotherapy) is more advocated. CONCLUSION: Breast cancer must be considered in the differential diagnosis of a patient with axillary lymphadenopathy. The conservative approach of OBC is the preferred since breast MRI does not identify any suspicious lumps.

Case report: solitary splenic metastasis occurring 19 months after primary treatment for occult breast cancer.

Occult breast cancer, commonly presenting with axillary lymphadenopathy, is an extremely rare entity of breast cancer. Metastasis to the spleen as a single site is rarely seen and has been little reported in literature. Herein we described a case of a 60-year-old patient who presented with an asymptomatic solitary splenic mass 19 months after axillary lymph node dissection, regional radiotherapy, and systemic therapy. Laparoscopic splenectomy was performed, and histopathological examination confirmed metastasis from occult breast cancer. Then, the patient was administered with oral vinorelbine and dual-targeted treatment. With over 10 months of follow-up, there is no evidence of recurrence or metastasis of malignancy. To our knowledge, this study reports the first case of solitary splenic metastasis from occult breast cancer and highlights the importance of considering splenic metastasis as the only site of recurrence during follow-up of primary cancer, regardless of its rarity. If possible, splenectomy may be a therapeutic strategy.

Occult breast cancer metastasis to the thyroid gland: Case report.

Thyroid metastases of occult breast cancer are very rare. A 48-year-old female patient presented with chronic bone pain, bone, liver and thyroid nodules, and pleural effusion. Histopathological result of the thyroid showed poorly differentiated papillary thyroid carcinoma. However, clinical laboratory and immunohistochemistry studies showed breast origin of the thyroid lesion.