Treatment and survival of patients with occult breast cancer with axillary lymph node metastasis: a nationwide retrospective study

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.

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.

Reconceptualizing the clinicopathological features, locoregional therapy and prognostic factors of occult breast cancer in the era of molecular subtyping

To evaluate the clinical features, molecular subtypes, therapeutic strategies, and prognostic factors of occult breast cancer (OBC). Patients with T0-3/N1-3/M0 breast cancer diagnosed in 2010-2018 (n = 114,303, including 691 with OBC) were retrieved from the Surveillance, Epidemiology, and End-Results (SEER) database. The endpoints were overall survival (OS) and breast cancer-specific survival (BCSS). Compared with non-OBC, OBC presented significantly more adverse clinicopathological prognostic features. More patients with OBC underwent breast-conserving treatment (BCT) and less had axillary lymphadenectomy (ALD). Outcomes were more favorable in OBC cases compared with non-OBC cases (p = .002 for OS, p = .002 for BCSS). Triple-negative (TNBC) and HER2-enriched were the subtypes with the worst prognosis in OBC (p < .05). Prognosis was better for triple-negative OBC compared with the same subtype of non-OBC. N-stage was not a strong prognostic indicator of OBC (p > .05 for OS). Cases who underwent systemic chemotherapy alone without surgery had the worst prognosis among OBC patients. For locoregional therapy, mastectomy and radiotherapy could confer survival advantage; standard axillary lymph node dissection (ALND) and positive lymph node dissection (PLND) contributed notably to OS in OBC patients. Both OS and BCSS were better in OBC cases compared with non-OBC. Systemic chemotherapy alone without surgery is not appropriate for OBC treatment, and mastectomy plus standard axillary surgery is recommended. Patients with hormone receptor-positive and low burden of axillary lymph node metastasis may be spared from radiotherapy after undergoing standard axillary lymphadenectomy.

Axillary lymph node dissection plus radiotherapy may be an optimal strategy for patients with occult breast cancer

Background

Because of the rarity of occult breast cancer (OBC) and limited experience in OBC treatment, the optimal treatment strategy is unknown. This study aimed to compare the efficacy of axillary lymph node dissection (ALND) plus radiotherapy with that of mastectomy plus ALND in patients with OBC.

Methods

Relevant clinical data between January 2004 and December 2015 were retrospectively collected from the Surveillance, Epidemiology, and End Results database. The clinical characteristics and prognoses of patients who underwent ALND plus radiotherapy or mastectomy plus ALND were compared before and after propensity score matching.

Results

Overall, 569 eligible patients with OBC were included in this study. Of these, 247 patients underwent ALND plus radiotherapy and 322 underwent mastectomy plus ALND. The 5-year overall survival (OS) rates in the ALND plus radiotherapy group and the mastectomy plus ALND group were 89.2% and 80.6%, respectively; and the corresponding 5-year breast cancer-specific survival (BCSS) rates were 95.2% and 93.0%, respectively. After propensity score matching, the OS in the ALND plus radiotherapy group was significantly better than that in the mastectomy plus ALND group. In addition, further subgroup analyses revealed that ALND plus radiotherapy prolonged OS in the pN3 subgroup. Among patients receiving adjuvant chemotherapy, those who underwent ALND plus radiotherapy had better BCSS and OS than those who underwent mastectomy plus ALND.

Conclusions

ALND plus radiotherapy could improve the OS of patients with OBC, especially those with pN3 disease and those receiving chemotherapy. ALND combined with radiotherapy is the optimal treatment strategy for patients with imaging-negative OBC.

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.

Clinicopathological characteristics and treatment outcomes of occult breast cancer: a population-based study

BACKGROUND

Occult breast cancer (OBC) is a special type of breast cancer. Because of its rarity, clinicopathological information is still insufficient, causing a controversial condition about its treatment recommendation. Thus, we aimed to clarify major clinicopathological information, treatment strategies and prognosis of OBC based on a large population.

METHODS

We retrospectively collected adult female OBC population from Surveillance, Epidemiology, and End Results database. We divided the whole cohort into two groups based on surgical treatment in-breast. Descriptive analysis of 18 clinicopathological variables was conducted. Survival analysis was performed based on different clinicopathological factors. Univariate and multivariate Cox regression analysis was performed to identify potential independent predictor for prognosis of OBC.

RESULTS

1189 OBC patients were in final analysis and most of them were diagnosed as an early-stage carcinoma. Patients received breast-conserving treatment (BCT) was nearly two times of ones received mastectomy. Patients receiving radiotherapy in BCT group were significantly more than patients receiving radiotherapy in mastectomy group (61.76 vs. 50.9%, P  <   0.001). After a median follow-up period of 62 months, 5-year and 10-year overall survival (OS) of all subjects was 81.6% and 68.8%, respectively. No significant difference in OS and breast-cancer specific survival (BCSS) was found between mastectomy and local breast-conserving surgery. Older age and larger number of positive lymph nodes causes a worse prognosis whereas radiotherapy brought a better clinical outcome for OBC patients.

CONCLUSIONS

OBC has a generally good prognosis. Less-intensive surgery does not negatively impact clinical outcomes of OBC while additional radiotherapy is totally beneficial to prolong OS and BCSS.

ICG-Loaded PEG-Modified Black Phosphorus Nanosheets for Fluorescence Imaging-Guided Breast Cancer Therapy

Indocyanine green (ICG) has been used in various surgical navigation systems and plays an important role in intraoperative imaging diagnosis. However, the poor photostability and unsatisfactory tumor-targeting ability have limited its broad application prospects. In the decades, the construction of a nanodrug delivery system for tumor-targeting diagnosis and therapy has become a research hotspot. Black phosphorus nanosheets (BPNS), as a new kind of biodegradable nanomaterials, have the advantages of high loading capacity, good biocompatibility, tumor targeting, and photothermal effect over other two-dimensional (2D) reported nanomaterials. Herein, ICG-loaded poly(ethylene glycol) (PEG)-modified BPNS (ICG@BPNS-PEG) nanocomposites are constructed to improve the tumor-targeting capacity and guide photothermal therapy through real-time fluorescence imaging. In this study, ICG@BPNS-PEG nanocomposites with a suitable size (240 ± 28 nm) have been successfully constructed. The photostability of ICG@BPNS-PEG nanocomposites surpassed that of free ICG after four on-off cycles of near laser irradiation (NIR). Moreover, ICG@BPNS-PEG nanocomposites have enhanced photothermal conversion ability. The cellular uptake result through flow cytometry showed that ICG@BPNS-PEG nanocomposites could be swallowed easily owing to the suitable size and passive cellular uptake. In addition, the cytotoxicity evaluation of MCF-7, 4T1 breast cancer cells, and healthy RPE cells through the MTT assay demonstrated that ICG@BPNS-PEG nanocomposites have lower cytotoxicity and good cellular compatibility without irradiation. However, the cytotoxicity and live/dead staining proved that ICG@BPNS-PEG nanocomposites have satisfactory photothermal therapeutic effects when irradiated. In the 4T1-bearing mice model, the fluorescence imaging after intravenous injection of nanocomposites showed that ICG@BPNS-PEG nanocomposites have superior passive tumor targeting accumulation through the enhanced permeability and retention (EPR) effect compared with that of free ICG. Also, changes in tumor volume showed a remarkable tumor growth inhibition effect compared with other groups. Moreover, the results of hematoxylin-eosin (H&E) staining of major organs in 4T1-bearing mice also demonstrated that the nanocomposites have good biocompatibility. Therefore, the constructed ICG@BPNS-PEG nanocomposites have substantial potential in breast cancer therapy.

Prognosis of patients with axillary lymph node metastases from occult breast cancer: analysis of multicenter data

Purpose

This study was conducted to evaluate prognosis of patients with level I/II axillary lymph node metastases from occult breast cancer (OBC).

Materials and Methods

Data of 53 patients with OBC who received axillary lymph node dissection (ALND) positive/negative (+/–) breast-conserving surgery between 2001 and 2013 were retrospectively collected at seven hospitals in Korea. The median number of positive lymph nodes (+LNs) was 2. Seventeen patients (32.1%) had >3 +LNs. A total of 48 patients (90.6%) received radiotherapy. Extents of radiotherapy were as follows: whole-breast (WB; n = 11), regional lymph node (RLN; n = 2), and WB plus RLN (n = 35).

Results

The median follow-up time was 85 months. Recurrence was found in four patients: two in the breast, one in RLN, and one in the breast and RLN. The 5-year and 7-year disease-free survival (DFS) rates were 96.1% and 93.5%, respectively. Molecular subtype and receipt of breast radiotherapy were significantly associated with DFS. Patients with estrogen receptor negative, progesterone receptor negative, and human epidermal growth factor receptor 2 negative (ER-/PR-/HER2-) subtype had significantly lower 7-year DFS than those with non-ER-/PR-/HER2- tumor (76.9% vs. 100.0%; p = 0.03). Whole breast irradiation (WBI) was significantly associated with a higher 7-year DFS rate (94.7% for WBI group vs. 83.3% for non-WBI group; p = 0.01). Other factors including patient’s age, number of +LNs, taxane chemotherapy, and RLN irradiation were not associated with DFS.

Conclusion

Patients with OBC achieved favorable outcome after ALND and breast-targeting treatment. Molecular subtype and receipt of WBI was significant factors for DFS.

Histologic Discordance Between Primary Tumor and Nodal Metastasis in Breast Cancer: Solving a Clinical Conundrum in the Era of Genomics

Next-generation sequencing (NGS) technologies have become increasingly used for managing breast cancer. In addition to the conventional use of NGS for predicting recurrence risk and identifying potential actionable mutations, NGS can also serve as a powerful tool to understand clonal origin and evolution of tumor pairs and play a unique role in clarifying complex clinical presentations. We report an unusual case of early-stage breast cancer in which the primary tumor and draining axillary node were histologically discordant. The primary tumor was invasive lobular carcinoma, whereas the nodal metastasis was invasive ductal carcinoma. This discordance led us to question whether the tumors had the same origin. NGS performed on both specimens identified no overlapping variants, leading us to conclude that the patient had two separate primary breast cancers, with the nodal tumor representing metastasis from an occult breast cancer. DNA sequencing of the primary tumor and the nodal metastasis allowed us to predict the patient's recurrence risk, and we initiated adjuvant chemotherapy and hormonal therapy based on these results. This case illustrates the utility of NGS for successfully managing a rare and challenging case. KEY POINTS: A degree of molecular concordance is expected for tumors originating from a common stem or progenitor cell. Histological discordance and absence of any genomic overlap should raise suspicion for two separate primary tumors. Paired DNA sequencing of the primary tumor and nodal metastasis can inform clinical decisions when primary breast tumor and axillary metastasis are histologically discordant. Molecular/Precision Oncology Tumor Board is the best setting to facilitate such decisions in these challenging cases. Paired DNA sequencing under these rare circumstances may suggest an occult breast tumor.

Application of neoadjuvant chemotherapy combined with anlotinib in occult breast cancer: A case report and review of literature

BACKGROUND

Occult breast cancer (OBC) is a special type of breast cancer presenting as axillary lymph node metastasis with undetectable primary lesions in the breast. Due to its low incidence and unique clinical manifestations, there is a lack of consensus on the diagnosis and treatment of OBC. We report a case of OBC treated with neoadjuvant chemotherapy combined with anlotinib. The treatment was well tolerated, and the patient achieved a pathologic complete response.

CASE SUMMARY

A 53-year-old woman presented with a lump in her right axillary area with no primary lesions in the breast. Pathological biopsy confirmed right axillary metastatic carcinoma. Immunohistochemical staining results were positive for progesterone receptor, cytokeratin 7, specific breast markers GATA3 and gross cystic disease fluid protein-15. Tumor cells were negative for estrogen receptor, human epidermal growth factor receptor-2, cytokeratin 5/6, cytokeratin 20, and villin. The patient was diagnosed with OBC, and she underwent neoadjuvant chemotherapy combined with anlotinib. Mastectomy plus axillary lymph node dissection was performed. The patient achieved pathologic complete response with no residual invasive tumor cells in the breast or axillary lymph nodes. Postoperatively, she received adjuvant radiotherapy and endocrine therapy.

CONCLUSION

Neoadjuvant chemotherapy and anlotinib had good efficacy and safety in the treatment of OBC and may be a new therapeutic option.

Eliminating the breast cancer surgery paradigm after neoadjuvant systemic therapy: current evidence and future challenges

In patients with operable early breast cancer, neoadjuvant systemic treatment (NST) is a standard approach. Indications have expanded from downstaging of locally advanced breast cancer to facilitate breast conservation, to in vivo drug-sensitivity testing. The pattern of response to NST is used to tailor systemic and locoregional treatment, that is, to escalate treatment in nonresponders and de-escalate treatment in responders. Here we discuss four questions that guide our current thinking about 'response-adjusted' surgery of the breast after NST. (i) What critical diagnostic outcome measures should be used when analyzing diagnostic tools to identify patients with pathologic complete response (pCR) after NST? (ii) How can we assess response with the least morbidity and best accuracy possible? (iii) What oncological consequences may ensue if we rely on a nonsurgical-generated diagnosis of, for example, minimally invasive biopsy proven pCR, knowing that we may miss minimal residual disease in some cases? (iv) How should we design clinical trials on de-escalation of surgical treatment after NST?

Occult breast cancer: Where are we at?

Occult breast cancer (OBC) is described as an axillary metastatic carcinoma without detection of a primary breast lesion and is uncommon. Significant advances in breast imaging have occurred since its description, decreasing its incidence. However current management is based upon old studies, with variable clinical, radiological and pathological definitions of OBC. We suggest standardised definitions of OBC to facilitate more homogenous data representation in the literature. This review also discusses the conflicting heterogeneous data and its influence in determining the current management guidelines. We discuss whether the current significant surgical recommendations are necessary and postulate whether they could be safely substituted with less invasive management.

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Pathological occult breast cancer is defined as no lesion detectable on MRI or pathological breast lesion post-surgery when examined at 5mm slices

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NAC in OBC may result in the de-escalation of axillary surgery.

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Current evidence indicates that ALND with ipsilateral breast RT has equivalent outcomes compared to ALND with mastectomy

Different Clinicopathological Characteristics and Prognostic Factors for Occult and Non-occult Breast Cancer: Analysis of the SEER Database

Purpose: The aim of our study was to evaluate the different clinicopathological characteristics and prognostic factors for occult and non-occult breast cancer. Methods: 572 OBC cases and 117,217 non-OBC patients between 2004 and 2015 was selected from Surveillance, Epidemiology, and End Results (SEER) database. We analyzed the clinicopathological characteristics and survival outcomes between OBC and non-OBC patients. Furthermore, the propensity score matching method was utilized to reduce the influences of baseline differences in demographic and clinical characteristics on outcome differences. Univariable and multivariable analyses were used to evaluate the prognostic factors of OBC patients. Results: Compared with non-OBC patients, OBC patients in this study presented a higher proportion of older age, American Joint Committee on Cancer (AJCC) N3 stage, estrogen receptor (ER)-negative status, progesterone receptor (PR)-negative status, and human epidermal growth factor receptor-2 (HER-2)-positive status, and underwent more chemotherapy. Multivariate analysis revealed a better survival in overall patients with OBC patients according to breast cancer-specific survival (BCSS) and overall survival (OS). Propensity score analysis also achieved a similar result for OBC patients. Stratified analyses by nodal status and molecular subtypes indicated that these survival advantage were mainly presented in patients with AJCC N2/N3 stage or hormone receptor (HR)-positive tumors. In addition, nodal status, HER-2 status, and radiation status were demonstrated to be three independent prognostic factors for OBC patients. Conclusion: Patients with OBC retained exclusive clinical characteristics and were shown to have a better outcome compared with non-OBC patients, especially for those with N2/N3 stage or HR-positive tumors.

Surgical Management of the Axilla in Patients with Occult Breast Cancer (cT0 N+) After Neoadjuvant Chemotherapy

BACKGROUND

Occult breast cancer (OBC) is a rare clinical entity. Current surgical management includes axillary lymphadenectomy (ALND) with or without mastectomy. We sought to investigate the role of sentinel lymph node biopsy (SLNB) in patients with OBC treated with neoadjuvant chemotherapy (NAC).

METHODS

Patients with clinical T0N+ breast cancer were selected from the National Cancer Data Base (NCDB, 2004-2014) and compared according to axillary surgical approach, SLNB (≤ 4 LNs) or ALND (> 4 LNs). Primary outcome was overall survival (OS), calculated using Kaplan-Meier methods. Secondary outcome was complete pathological response (pCR).

RESULTS

A total of 684 patients with OBC were identified: 470 (68.7%) underwent surgery upfront and 214 (31.3%) received NAC. Of the NAC patients, 34 (15.9%) underwent SLNB and 180 (84.1%) ALND. One hundred and fifty-three (72%) patients received radiotherapy (RT). There was no difference in pCR rates between the ALND and SLNB (34.3% vs 24.5%, respectively p = 0.245). In patients undergoing surgery first, improved OS was observed with ALND compared to SLNB (106.9 vs 85.5 months, p = 0.013); however, no difference in OS was found in patients who received NAC (105.6 vs 111.3 months, p = 0.640). RT improved OS in patients who underwent NAC followed by SLNB (RT, 123 months vs no RT, 64 months, p = 0.034). Of NAC patients who did not undergo RT, ALND had superior survival compared to SLNB (113 vs 64 months, p = 0.013).

CONCLUSION

This is the first comparative analysis assessing the surgical management of the axilla in patients with OBC who underwent NAC. In this population, there was a decrease in survival in patients who underwent SLNB alone; however, with the addition of RT, there was no difference in OS between SLNB and ALND. SLNB plus RT may be considered as an alternative to ALND in patients with OBC who have a good response to NAC.

Treatment for occult breast cancer: A propensity score analysis of the National Cancer Database

BACKGROUND

Controversy exists regarding optimal treatment of occult breast cancer (OBC). Treatment options include mastectomy alone (MAST), radiation alone (XRT), or mastectomy with radiation (MXRT).

METHODS

We queried the National Cancer Database from 2004 to 2014 for patients with OBC who underwent MAST, XRT, or MXRT. We utilized propensity score matching to perform three head-to-head comparisons. Kaplan-Meier analysis was performed to compare overall survival (OS).

RESULTS

A total of 190 patients received XRT, 237 received MAST, and 244 received MXRT. In the MXRT vs. XRT comparison, 5-year OS was 78.2% and 82.8%, respectively. In the MXRT vs. MAST comparison, 5-year OS was 81.5% and 86.7%, respectively. In the MAST vs. XRT comparison, 5-year OS was 83.2% and 82.5%, respectively. There was no difference in OS for all paired comparisons.

CONCLUSIONS

There were no OS differences in patients undergoing MAST, XRT, or MXRT, suggesting that breast conservation can be considered in patients with OBC.

Outcome of breast-conserving treatment for axillary lymph node metastasis from occult breast cancer with negative breast MRI

Purpose

We conducted this study to investigate the prognosis and failure pattern after breast-conserving treatment (BCT) in patients with occult breast cancer (OBC) with negative breast magnetic resonance imaging (MRI) (MRI-OBC).

Materials and methods

Survival rates and failure patterns in 66 patients who received axillary lymph node dissection (ALND) and BCT for MRI-OBC between 2001 and 2013 at seven hospitals were analyzed. OBC was defined as adenocarcinoma in the axillary lymph node (ALN) +/− supraclavicular (SCN) or internal mammary lymph node (IMN) with a negative breast MRI.

Results

Fifty-four patients had only ALN metastasis (ALN only), and 12 patients had ALN metastasis along with SCN or IMN metastasis (ALN + SCN/IMN). Median follow-up was 82 months. The 5-year overall, disease-free, and breast cancer-free survival rates were 93.4%, 92.1%, and 96.8%, respectively. Nine patients experienced recurrence: breast (n = 4), regional lymph nodes (RLN, n = 1), distant metastases (DM, n = 2), breast/RLN (n = 1), and breast/RLN/DM (n = 1). Five-year disease-free survival was significantly higher in ALN only patients compared to ALN + SCN/IMN patients (96.1% vs. 75.0%; p = 0.02).

Conclusions

Patients with MRI-OBC were successfully treated with BCT. There was a small risk of ipsilateral breast cancer recurrence. Failure patterns depended on the extent of initial disease.

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Occult breast cancer (OBC) presenting with axillary metastases is a rare disease.

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This study reports on the outcome of OBC with negative breast MRI (MRI-OBC).

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Patients with MRI-OBC were successfully treated with breast-conserving treatment.

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Very few breast recurrences occurred when whole breast radiotherapy was used.

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Failure patterns of MRI-OBC depended on the initial extent of nodal involvement.

The potential role of carbon nanoparticles-assisted biopsy for sentinel lymph nodes of incidental thyroid carcinoma

Background

Some thyroid cancers are found after thyroidectomy for benign lesions, implying additional surgery and treatments. This work aimed to investigate the role of intraoperative sentinel lymph node biopsy (SLNB) for diagnosis of incidental thyroid carcinoma.

Methods

This was a retrospective study of 541 consecutive patients who underwent thyroid surgery between 02/2012 and 02/2014 at the Hunan Provincial People's Hospital. All patients were diagnosed with thyroid benign lesions preoperatively and intraoperatively. Among them, 375 underwent successful intraoperative SLNB using carbon nanoparticles (CNs).

Results

The preoperative diagnoses were nodular goiter (n=472), Hashimoto's disease with nodules (n=24), hyperthyroidism with nodules (n=16), and thyroid cysts with obstructive symptoms (n=29). In the SLNB group, SLN metastasis of thyroid microcarcinoma was confirmed in 21/392 cases (5.4%). These 21 patients received radical surgical treatment for thyroid carcinoma during the initial operation. In the no-SLNB group (n=149), seven patients (4.7%) were finally diagnosed with thyroid microcarcinoma. Six patients had to undergo a second surgery.

Conclusions

Intraoperative SLNB could help diagnose differentiated thyroid microcarcinoma that may be missed preoperatively and intraoperatively. This could prevent the need for a second surgery since the intraoperative frozen section examination of the SLNs can reveal metastasis from thyroid cancer.

Axillary lymph node metastasis as the first manifestation of male occult breast cancer: A Case Report

RATIONAL

Occult breast cancer (OBC) is an extremely rare breast cancer and is defined by the presence of axillary metastasis without a primary tumor in the breasts or any abnormality on radiologic examination.

PATIENT CONCERNS

This case report presents a 49-year-old man who was diagnosed with male OBC, which first manifested as an axillary lymph node metastasis followed by the emergence of infraclavicular lymph node metastasis. Neither the breast nor other organs had any abnormality.

DIAGNOSIS

The pathological examination revealed metastatic adenocarcinoma. Immunohistochemical (IHC) staining results were positive for estrogen receptor (ER), progesterone receptor (PR), and gross cystic disease fluid protein-15 (GCDFP-15); and negative for human epidermal receptor-2 (Her-2) 1+, cytokeratin (CK) 7, CK20, and thyroid transcription factor-1 (TTF-1).

INTERVENTIONS

The patient underwent left axillary lymph node dissection but not a mastectomy. After the operation, the patient subsequently underwent chemotherapy, radiotherapy, and endocrinotherapy.

OUTCOMES

Currently, he has been followed-up for >4 years without any signs of recurrence.

LESSONS

Careful physical and imaging examinations combined with pathological analysis are essential in the diagnosis of male OBC. Early surgery remains the primary treatment.

Clinicopathological characteristics and treatment outcomes of occult breast cancer: a SEER population-based study

Background

Occult breast cancer (OBC) is a rare type of breast cancer that has not been well studied. The clinicopathological characteristics and treatment recommendations for OBC are based on a limited number of retrospective studies and thus remain controversial.

Patients and methods

We identified 479 OBC patients and 115,739 non-OBC patients from 2004 to 2014 in and the Surveillance, Epidemiology, and End Results (SEER) database. The clinicopathological characteristics and survival outcomes were compared between OBC and non-OBC patients. We used the propensity score 1:1 matching analysis to evaluate OBC vs non-OBC comparison using balanced groups with respect to the observed covariates. We further divided the OBC population into four groups based on different treatment strategies. Univariable and multivariable analyses were used to calculate and compare the four treatment outcomes within the OBC population.

Results

OBC patients were older, exhibited a more advanced stage, a higher rate of negative estrogen receptor and progesterone receptor status, a higher rate of HER2-positive status, and a higher rate of ≥10 positive lymph nodes, and were less likely to undergo surgical treatment than non-OBC patients. After adjustments for clinicopathological factors, the OBC patients exhibited a significantly better survival than the non-OBC patients (P<0.001). This result was confirmed in a 1:1 matched case–control analysis. Within the four OBC treatment groups, we observed no difference in survival among the mastectomy group, the breast-conserving surgery (BCS) group, and the axillary lymph node dissection (ALND)-only group. The multivariable analysis revealed that the sentinel lymph node dissection-only group had the worst prognosis (P<0.001). Conclusion: OBC has unique clinicopathological characteristics and a favorable prognosis compared with non-OBC. BCS plus ALND and radiotherapy showed a survival benefit that was similar to that of mastectomy for OBC patients.

Occult breast cancer may originate from ectopic breast tissue present in axillary lymph nodes

PURPOSE

Occult breast cancer (OBC) is classified as a carcinoma of unknown primary, and involves axillary lymphadenopathy and is histologically consistent with metastatic breast cancer. OBC has been conventionally considered as a metastatic lymph node lesion, the origin of which is an undetectable breast tumor. Therefore, OBC patients would usually have undergone axillary lymph node dissection, and mastectomy or whole breast radiotherapy (WBRT). However, majority of OBC reports have been based on cases that were diagnosed during a period when diagnostics was still relatively primitive, and when magnetic resonance imaging was not yet a standard preoperative assessment. Therefore, there have been many false negatives in the breast based on preoperative assessment.

METHODS

We herein hypothesize that the origin of OBC is ectopic breast tissue present in axillary lymph nodes (ALNs). If our hypothesis is true, mastectomy and WBRT may be unnecessary for OBC patients.

RESULTS

Our hypothesis is supported by several findings. First, advances in radiological imaging have suggested that a primary breast tumor is absent in OBC patients. Second, proliferative breast lesions arising from ectopic breast present in ALNs have been reported. Lastly, cellular subtypes in OBC based on immunohistochemistry are of various types including ordinary breast cancer and the prognosis is not worse than stage II breast cancer.

CONCLUSION

It is important to distinguish between "primary" OBC in ALNs and "metastatic" OBC from micro-primary breast tumor. Further studies are required to determine if omission of mastectomy and WBRT is acceptable.

Male occult breast cancer with axillary lymph node metastasis as the first manifestation: A case report and literature review

RATIONALE

Occult breast cancer (OBC) is extremely rare in males with neither symptoms in the breast nor abnormalities upon imaging examination.

PATIENT CONCERNS

This current case report presents a young male patient who was diagnosed with male OBC first manifesting as axillary lymph node metastasis. The physical and imaging examination showed no primary lesions in either breasts or in other organs.

DIAGNOSES

The pathological results revealed infiltrating ductal carcinoma in the axillary lymph nodes. Immunohistochemical (IHC) staining was negative for estrogen receptor (ER), progesterone receptor (PR), cytokeratin (CK)20 and thyroid transcription factor-1 (TTF-1), positive for CK7, gross cystic disease fluid protein-15 (GCDFP-15), epithelial membrane antigen (EMA) and carcinoembryonic antigen (CEA), and suspicious positive for human epidermal receptor-2 (Her-2). On basis of IHC markers, particularly such as CK7, CK20 and GCDFP-15, and eliminating other malignancies, male OBC was identified in spite of negativity for hormone receptors.

INTERVENTIONS

The patient underwent left axillary lymph node dissection (ALND) but not mastectomy. After the surgery, the patient subsequently underwent chemotherapy and radiotherapy.

OUTCOMES

The patient is currently being followed up without any signs of recurrence.

LESSONS

Carefully imaging examination and pathological analysis were particularly essential in the diagnosis of male OBC. The guidelines for managing male OBC default to those of female OBC and male breast cancer.

Application of neoadjuvant chemotherapy in occult breast cancer: Five case reports

RATIONALE

Although rare, occult breast cancer (OBC) originates from breast tissue. Its primary lesions cannot be identified by clinical examination or imaging; therefore, the diagnosis, treatment, and prognosis remain controversial.

PATIENT CONCERNS

This study comprised 5 female OBC patients who were admitted to the Affiliated Hospital of Guizhou Medical University for painless axillary lumps.

DIAGNOSES

F-flurodeoxyglucose (F-FDG) positron emission tomography/computed tomography (PET/CT) indicated metastasis in the ipsilateral axillary lymph nodes. No clear breast primary lesions were identified; other organs were also excluded as the primary site. Pathological biopsy confirmed axillary lymph node metastasis of adenocarcinoma. Immunohistochemical staining of the tumor to identify the source revealed that estrogen receptors (ERs) and progesterone receptors (PgRs) were positive in 2 cases, ER was positive and PR was negative in 1 case, and both were negative in 2 cases. Human epidermal growth factor receptor 2 was negative in all cases. All patients were diagnosed with OBC.

INTERVENTIONS

All patients underwent neoadjuvant chemotherapy (NAC). One patient did not undergo follow-up therapy. The other 4 underwent total mastectomy plus axillary lymph node dissection followed by radiotherapy. Two patients also underwent endocrine therapy.

OUTCOMES

Patients were followed up for 9.0 to 72.0 months. Four achieved pathological complete response. One patient experienced metastasis to the ipsilateral supraclavicular lymph nodes 2.0 years later, which was cleared after additional treatment. The other patients were tumor free.

LESSONS

Here, we are reporting 5 cases of OBC treated with NAC that were evaluated by F-FDG PET/CT scans. This study suggests that NAC might lead to a positive outcome.

Oncologic Outcomes After Treatment for MRI Occult Breast Cancer (pT0N+)

BACKGROUND

Studies assessing outcomes in occult breast cancer have often included women treated before the routine use of magnetic resonance imaging (MRI). This study examined outcomes for patients presenting with axillary adenopathy and no primary breast tumor detectable by MRI or other imaging methods.

METHODS

All patients with axillary nodal metastases consistent with breast carcinoma and no breast primary tumor detectable by physical exam, mammography, or MRI treated between 1 January 1996 and 30 June 2011 were identified from an institutional database. Data were collected on local, regional, and distant recurrences.

RESULTS

For the study, 38 patients were identified. Modified radical mastectomy (MRM) was performed for 13 of the patients, whereas 25 of the patients underwent axillary dissection (ALND) and whole-breast radiotherapy (WBRT). Most of the women had pathologic N1 disease [median number of positive nodes, 2 (MRM cohort) and 3 (ALND + WBRT cohort); p = 0.38]. All the patients received chemotherapy, and 30 (79%) of the 38 patients received an anthracycline and taxane. Regional nodal radiation was used for 60% of those with ALND + WBRT and for all 46% of the MRM patients who received chest wall radiotherapy. During a median follow-up period of 7 years, there were no nodal recurrences. Two patients treated with ALND + WBRT had in-breast recurrences, whereas none in the MRM group experienced a local recurrence. The proportion that experienced distant disease was similar between the MRM cohort (1 of 13) and the ALND + WBRT cohort (2 of 25).

CONCLUSION

Breast cancer presenting as axillary adenopathy with no detectable primary tumor is rare. Breast conservation with WBRT is a viable option for patients with a diagnosis of occult breast cancer and a negative preoperative MRI.

Evaluation of the Benefit of Radiotherapy in Patients with Occult Breast Cancer: A Population-Based Analysis of the SEER Database

Purpose

Few studies for occult breast cancer (OBC) have evaluated the effect of radiotherapy (RT) after mastectomy or axillary lymph node dissection (ALND) with/without breast surgery. Therefore, we investigated clinicopathologic factors of OBC with the impact of postoperative RT to determine its prognostic significance using large population-based data.

Materials and Methods

We performed a retrospective cohort study using the Surveillance, Epidemiology, and End Results (SEER) database from 1983 to 2013. A total of 1,045 eligible patients with OBC were identified. We compared overall survival (OS) using Cox proportional hazards regression with propensity score matching after verifying an imbalance of prognosticators between RT group (n=518) and non-RT group (n=479).

Results

Patients with age < 70 (p=0.033), married marital status (p < 0.001), undergoing ALND (p < 0.001), more examined lymph nodes (LNs) (p < 0.001), and more metastatic LNs (p < 0.001) were more likely to receive RT. Multivariate analysis after propensity score matching (n=798) showed that patients treated with RT survived significantly longer than those without RT (5-year OS, 81.5% vs. 78.3%; p=0.014). A significantly prolonged OS was observed when RT was given to patients treated with mastectomy (p=0.033), those treated with ALND (p=0.036), or those with more than seven metastatic LNs (p=0.016).

Conclusion

RT may offer survival benefit in OBC even after mastectomy or ALND, especially in patients with more than seven metastatic LNs. Further prospective studies are needed to validate these findings.

[Axillary lymph node metastases with an occult breast: About 16 cases from a cohort of 7770 patients]

OBJECTIVES

Isolated axillary lymph node metastases is an unusual clinical presentation of breast carcinoma. We studied its different issues.

METHODS

This study is a follow-up study of 16patients, treated between 1996 and 2012, presenting with axillary metastases with an occult breast carcinoma, which could not be identified by physical examination nor by a conventional imaging or a breast MRI. Clinical characteristics, histological analysis, treatment, monitoring and five-year survival rate were studied.

RESULTS

The incidence of this kind of breast cancer was 0.20%. A breast MRI was performed in 75% of the patients. The histology of these tumors showed a rate of hormono-sensibility of 50% and an HER2 overexpression of 44%. Sixty-nine percent of the patients had no breast surgery or radiotherapy; global five-year survival rate for these women was 77.4%±11.5.

CONCLUSION

The survival rates of this study should lead the practitioner to choose a less aggressive breast therapy. Moreover, the histological characteristics explain the high metastatic potential of these tumors, and relate them to the HER2+ subclass of gene expression patterns of breast carcinomas.

A Case Report of Male Occult Breast Cancer First Manifesting as Axillary Lymph Node Metastasis With Part of Metastatic Mucinous Carcinoma

Occult breast cancer (OBC) is a type of breast cancer without any symptoms in the breast (no primary cancer lesion is found in either breast on a physical examination or imaging examination such as ultrasound and mammography). The incidence of OBC is rare in females, whereas in males, there are few cases of breast cancer, and the rate of OBC is very low. This is the first time report a case of male OBC first manifested as axillary metastasis, of which the pathological results showed moderately differentiated adenocarcinoma with part of metastatic mucinous carcinoma.A 40-year-old male patient presenting palpable masses in his left axillary on physical and imaging examination revealed unremarkable despite of multiple swollen lymph nodes in the left axillary, and the resected sample showed metastatic adenocarcinoma with part of metastatic mucinous carcinoma. Based on immunohistochemical analysis, positive of estrogen receptor (ER), progesterone receptor (PR), and human epidermal receptor 2 (Her-2), it was identified as an OBC.This is the fourth case report of male OBC in the literature; 1 case was reported in China in 2008, and it was metastatic infiltrating ductal carcinoma, and 2 cases were reported in Korea in 2012, one of which was reported as metastatic carcinoma and the other was metastatic adenocarcinoma; however, our case was a moderately differentiated adenocarcinoma with part of mucinous carcinoma. Our case of male OBC could metastasize to supraclavicular region and lung in addition to axillary lymph nodes, and the prognosis was relatively poor compared to the 3 cases reported before.The aim of this case report is to introduce the imaging, pathological features, and management of a rare male OBC.