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

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.

A Case Report of Occult Breast Cancer Detected by Diagnostic Laparoscopy for Suspected Ovarian Cancer

Diagnostic laparoscopy is useful in the management of gynecological cancers; however, it can occasionally result in the detection of other malignancies. Occult breast cancer (OBC) is metastatic breast cancer without a recognized primary breast lesion. We report a rare case of OBC that was detected laparoscopically. A 64-year-old female presented to our hospital with back pain. Magnetic resonance imaging (MRI) revealed a 50 mm multicystic tumor with an internal nodule in the right ovary. Positron emission tomography/computed tomography showed abnormal accumulation in multiple lymph nodes, moderate accumulation in the ovarian tumor nodule, and no accumulation in the breasts. Ovarian cancer was suspected, and a diagnostic laparoscopy was performed. Laparoscopically, a cystic tumor in the right ovary and 10 mm nodule in the right round ligament were observed and partially resected. Immunohistopathologically, the nodules of the round ligament exhibited features consistent with those of breast cancer, but the ovarian tumor was a seromucinous borderline tumor. MRI revealed no breast lesions. Therefore, the malignancy was diagnosed as an OBC.

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.

The Elusive Primary: Metastatic Adenocarcinoma of the Breast Presenting Solely as a Hard Sternal Mass

BACKGROUND Carcinoma of unknown primary (CUP) is a diverse category of malignancies diagnosed in patients who have metastatic disease but without an identifiable primary tumor at initial presentation. CASE REPORT We report a case of CUP which was later diagnosed to be metastatic adenocarcinoma of the breast in a 62-year-old woman. The patient initially presented to a primary care clinic with an incidental finding of a small hard mass in the middle of the sternum, with no other clinical findings in the breast or axillary lymph nodes. Chest X-ray, ultrasound, and CT scan of the sternum suggested a benign sternal lesion, and a mammogram was normal. Due to the persistence of the mass, a biopsy was performed. The histopathological findings revealed a metastatic adenocarcinoma, most likely from breast origin, with positive estrogen receptor (ER) and mammaglobin on immunohistochemistry studies. The patient subsequently underwent PET scan, repeat mammogram, and MRI of the breast. Following high uptake in the rectum on PET, a colonoscopy was performed, revealing a suspicious rectal mass. The mass was surgically excised, and the final histopathological examination concluded the mass was a second primary adenocarcinoma of the rectum. Genetic analyses for BRCA1 and BRCA2 were negative. CONCLUSIONS This is a rare case of an isolated bone-like lesion on the sternum due to metastatic adenocarcinoma of the breast in a patient with no prior history of breast cancer and lacking any clinical or radiological evidence of breast or axillary lymph node lesions on presentation. The patient was also subsequently diagnosed with 2 primary carcinomas. Thorough clinical examination, extensive radiological investigations, laboratory investigations, histopathological examination, and a multidisciplinary approach are essential in managing CUP.

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.

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.

[Breast-like cancer of unknow primary : Implications for radiological diagnostics]

BACKGROUND

Cancer of unknown primary (CUP) is defined by the presence of metastatic disease with an undetectable primary tumor at the time of presentation despite standard-of-care imaging. Although the prognosis of most CUP patients is poor, certain subgroups with more favorable prognosis have been defined.

DIAGNOSTICS

Women with isolated axillary lymph node metastases and confirmed histologic adenocarcinoma or poorly differentiated subtype, no other distant metastases, and no evidence of a primary cancer including primary breast carcinoma evaluated by clinical examination, computed tomography of thorax and abdomen, mammography, breast ultrasound, and breast magnetic resonance imaging (MRI) represent a potentially curable subgroup of patients with CUP. Breast MRI is the most important radiological modality in the diagnostic workup of breast-like CUP to exclude a primary cancer in the breast.

THERAPY

Breast-like CUP patients are treated according to guidelines for patients with node-positive breast cancer. Standard-of-care adjuvant systemic therapy should be given. Axillary lymph node dissection (ALND) is indicated. If no primary cancer in the breast is detected, surgery of the ipsilateral breast should not be performed. Radiotherapy of the ipsilateral breast and supra-/infraclavicular lymph nodes should be discussed.

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.

Survival analysis and nomogram for early-stage occult breast cancer with positive lymph nodes based on the SEER database

Background

Occult breast cancer (OBC) is a rare type of breast cancer, which accounts for 0.3-1.0% of all breast cancers. However, the treatment of OBC remains controversial, especially the local treatment. We aimed to analyze the impact of different treatment and N stage on survival in early-stage OBC patients, and construct a nomogram to predict the prognosis.

Methods

The data of patients with early-stage breast cancer were obtained from 17 registries in the Surveillance, Epidemiology, and End Results (SEER) database. Patient characteristics and breast cancer-specific survival (BCSS) were compared among the groups. Cox proportional risk models were used for both the univariate and multivariate analyses. Variables with a P value <0.07 in the univariate analysis were included in the multivariate analysis. The independent prognostic factors were included in the nomogram and validated internally.

Results

A total of 492 early-stage OBC patients were randomized at a 7:3 ratio into the training cohort (n=348) and the testing cohort (n=144). N2+ stage patients had a worse prognosis than N1 stage patients (P=0.0051). Triple-negative breast cancer (TNBC) patients had the worst prognosis. Early-stage OBC patients benefited from surgery (P=0.0093) and radiotherapy (P=0.0102), but not chemotherapy (P=0.4030). An analysis of OBC patients with different N stages showed that in terms of treatment, N1 stage patients benefited from surgery (P=0.023), but did not benefit significantly from radiotherapy (P=0.0793), whereas N2+ stage patients benefited from radiotherapy (P=0.0098), but the benefit from surgery was not significant (P=0.1005). In the multivariate analysis, N stage, surgery, and radiotherapy remained statistically significant. Based on the results of the multivariate analysis, we constructed a nomogram for estimating the 3- and 5-year BCSS of OBC patients. The concordance index and the calibration plots show that our nomogram had sufficient accuracy and good coordination.

Conclusions

N stage, surgery, and radiotherapy were identified as independent prognostic factors for OBC. We successfully constructed a nomogram using these independent risk factors and demonstrated that it could help predict the 3- and 5-year BCSS of OBC patients. Further data analyses need to be conducted to revise the treatment of early-stage OBC.

Cutaneous metastasis of occult breast cancer: a case report

Occult breast cancer (OBC) is characterized by metastatic presentation of undetectable breast tumor on imaging exams. OBC is a rare disease (accounting for 0.3% to 1.0% of all breast cancers) that represents a major diagnostic challenge. The aim of this study was to report a case of OBC with primary presentation of multiple cutaneous metastases with subsequent emergence of bone metastasis. A 70-year female patient had multiple cutaneous metastatic lesions in the left cervical region, left breast, left axillary region, left subscapular region, in three chirodactylus of the right hand and three chirodactylus of the left hand. Imaging tests (mammogram, ultrasonography and magnetic resonance imaging of the breast) did not show alterations. Biopsy, histology sections and immunohistochemistry of the left cervical cutaneous lesion were compatible with OBC. After two years of anastrozole treatment (1mg/day), there was regression of all cutaneous lesions and stabilization of bone metastasis. OBC has a better prognosis. It may exhibit spontaneous regression or respond to less aggressive treatment strategies, as described in this case.