Adjuvant radiation therapy and survival for pure tubular breast carcinoma--experience from the SEER database

Special Histologic Type and Rare Breast Tumors - Diagnostic Review and Clinico-Pathological Implications

Breast cancer is the most common malignant tumor in females. While most carcinomas are categorized as invasive carcinoma, no special type (NST), a diverse group of tumors with distinct pathologic and clinical features is also recognized, ranging in incidence from relatively more common to rare. So-called "special histologic type" tumors display more than 90% of a specific, distinctive histologic pattern, while a spectrum of tumors more often encountered in the salivary gland may also arise in the breast. Metaplastic carcinomas can present diagnostic challenges. Some uncommon tumors harbor pathognomonic genetic alterations. This article provides an overview of the key diagnostic points and differential diagnoses for this group of disparate lesions, as well as the salient clinical characteristics of each entity.

Special subtypes with favorable prognosis in breast cancer: A registry-based cohort study and network meta-analysis

BACKGROUND

We aimed to explore whether cribriform and adenoid cystic carcinoma had comparable prognoses to mucinous, tubular and papillary carcinoma, which were long recognized as favorable histologies by NCCN guidelines.

METHODS

A retrospective analysis based on the Surveillance, Epidemiology, and End Results Study (SEER) database (1994-2014) was conducted. The prognostic significance of all clinicopathological factors was calculated using univariate and multivariate analyses. A systematic review based on PubMed and network meta-analysis was conducted.

RESULTS

From the SEER database, the histologic subtypes of breast cancer (tubular, cribriform, adenoid cystic, mucinous, and papillary) were sorted by overall survival (OS) (94.4%, 91.6%, 90.8%, 87.6%, and 84.2%, respectively) and tubular, cribriform, mucinous, papillary, and adenoid cystic carcinoma by breast cancer-specific survival (BCSS) (99.4%, 98.4%, 97.7%, 95.2%, and 94.9%, respectively). A network meta-analysis combining 11 studies (886,649 patients) was conducted, which demonstrated consistent outcomes. SEER-based analyses revealed that, among the favorable subtypes, systemic chemotherapy did not improve OS or BCSS in hormone receptor-positive, node-negative patients, validating that these subtypes are generally associated with excellent outcomes, for which systemic chemotherapy may not be warranted.

CONCLUSIONS

Our data are consistent with guidelines suggesting that the mucinous, tubular, and papillary subtypes of breast cancer have favorable histologies. SEER data and meta-analysis supports this favorable category to include adenoid cystic and cribriform carcinoma, whose OS and BCSS outcomes are comparable to the former three. These findings add to the body of data, suggesting that patients with these histologic subtypes confer excellent prognosis, which may guide optimal therapeutic management strategies.

Rare epithelial breast cancer: surgery and adjuvant therapy

Breast cancer is a heterogenous disease, exhibiting a wide range of morphological phenotypes shaping its prognosis and clinical course. However, optimal management of rarer breast cancer subtypes is often undefined and controversial in literature due to the lack of large studies and randomised trials. This review aims to discuss the treatment of 13 rare epithelial subtypes, focussing on surgery and adjuvant therapies.

The effects of postoperative radiotherapy on survival outcomes in patients under 65 with estrogen receptor positive tubular breast carcinoma

Background

The value of postoperative radiotherapy in tubular breast carcinoma patients under 65 years is uncertain.

Methods

Data on patients with estrogen receptor positive T1N0M0 tubular breast carcinoma who were younger than 65 years and who received breast-conserving surgery between 2000 and 2013 were retrieved from the Surveillance, Epidemiology and End Results database. Demographic, clinicopathologic features, and receipt of postoperative radiotherapy were analyzed to investigate effects on survival.

Results

Data from 2442 patients were analyzed, of whom 2020 (82.7%) received postoperative radiotherapy and 422 (17.3%) did not. The number of patients treated with or without postoperative radiotherapy showed no differences during the study period (p = 0.184). Radiotherapy was more likely to be administered in patients with well differentiated tumors. Multivariate Cox analysis showed that postoperative radiotherapy delivery was significantly correlated with better breast cancer-specific survival (BCSS) (hazard ratio [HR] 0.297, 95% confidence interval [CI] 0.105–0.836, p = 0.022) and overall survival (OS) (HR 0.656, 95% CI 0.441–0.978, p = 0.038). Ten 10-year BCSS was 99.3% in patients who received postoperative radiotherapy and 98.1% in those who did not (p = 0.020), and 10-year OS was 93.4 and 91.0%, respectively (p = 0.029). Postoperative radiotherapy increased BCSS and OS in the subgroups of age < 50 years, non-Hispanic white, well differentiated tumors, and progesterone receptor positive tumors.

Conclusions

Postoperative radiotherapy after breast-conserving surgery improved survival outcomes in tubular breast carcinoma patients aged < 50 years. However, omitting postoperative radiotherapy may not decrease survival in patients aged ≥50 years.

Clinicopathologic characteristics and clinical outcomes of pure type and mixed type of tubular carcinoma of the breast: a single-institution cohort study

Introduction

We aimed to evaluate the clinicopathologic characteristics and clinical outcomes of the mixed type versus the pure type of tubular carcinoma (TC) of the breast in a retrospective cohort study.

Materials and methods

Patients were categorized into the following three groups: patients with pure TC of the breast (the PTC group), patients with TC and carcinoma in situ of the breast (the TC-CIS group), and patients with TC and other invasive carcinomas of the breast (the TC-IC group). We compared the clinicopathologic characteristics and treatment outcomes of the three groups. The primary end point of this study was breast cancer-specific survival (BCSS). Secondary end points included distant metastasis-free survival (DMFS) and locoregional recurrence (LRR).

Results

A total of 68 patients were included in this study, including 31 patients in the PTC group, 12 in the TC-CIS group, and 25 in the TC-IC group. Our data showed that PTC and TC-CIS were more likely to be smaller in size (P=0.014) and had substantially less nodal involvement (P=0.019), compared with TC-IC. The median follow-up time was 64.3 months (range, 3.78–223.2 months) for all patients. No locoregional relapse was observed in any group during the follow-up period. The 10-year BCSS of the PTC, TC-CIS, and TC-IC groups was 100%, 100%, and 95.2%, respectively, and the 10-year DMFS was 92.3%, 100%, and 96.0%, respectively. There was no significant difference in terms of BCSS (P=0.53) or DMFS (P=0.84) between the three groups.

Conclusion

This study indicates that both the pure type and mixed type of TC of the breast show very low LRR and distant metastasis rate and have excellent survival. The TC-IC group is likely to show good prognosis similar to the PTC group. Further clinical trials with larger sample sizes as well as molecular and genetic studies are warranted.

Tubular carcinomas of the breast: an epidemiologic study

AIM

We explored the clinicopathologic characteristics, prognostic factors and outcomes in tubular carcinoma (TC) of the breast.

METHODS

We retrospectively assessed 8091 TC patients using the SEER database from 2000 to 2013.

RESULTS

Most patients were non-Hispanic white, well-differentiated disease, tumor size ≤2 cm, node-negative, nonmetastatic, hormone receptor-positive and HER2-negative status. The 10-year breast cancer-specific survival and overall survival were 98.1 and 82.0%, respectively. Multivariate analysis indicated that age, ethnicity, surgery procedures, radiotherapy and chemotherapy were independent predictors affecting survival outcomes. There was comparable breast cancer-specific survival between surgery and nonsurgery groups.

CONCLUSION

The patients with TC has excellent survival outcomes, which may in part be due to the favorable tumor characteristics.

Omission of Postoperative Radiotherapy in Women Aged 65 Years or Older With Tubular Carcinoma of the Breast After Breast-Conserving Surgery

Introduction

To investigate the temporal trends of postoperative radiotherapy (RT) administration and the effects of omitting postoperative RT on breast cancer-specific survival (BCSS) in women aged ≥65 years with tubular carcinoma (TC) of the breast who received breast-conserving surgery (BCS).

Methods

We included women aged ≥65 years with non-metastatic TC of the breast who underwent BCS between 2000 and 2013 using the Surveillance, Epidemiology, and End Results database. Statistical analyses were performed using chi-square tests, Kaplan–Meier analyses, Cox proportional hazards models, and a 1:1 propensity score matching (PSM).

Results

Before PSM, a total of 1,475 patients with tumor size ≤2 cm, node-negative disease, and estrogen receptor-positive disease were identified, including 927 (62.8%) underwent postoperative RT and 548 (37.2%) had postoperative omission of RT. The administration of postoperative RT steadily declined over the study period. Patients with younger age, larger tumor size, and other race/ethnicity were more likely to receive postoperative RT. The median follow-up duration was 85.0 months, the 5- and 10-year BCSS rates were 98.7 and 97.9%, respectively. The median BCSS was 161.9 and 165.0 months for patients with and without postoperative RT, respectively, and the corresponding 5-year BCSS rates were 98.5 and 98.8%, respectively (p = 0.134). Prognostic analysis indicated that postoperative RT was not associated with improved BCSS rates compared with RT omission (p = 0.134). After PSM, a total of 431 complete pairs were generated. In the matched population, the 5-year BCSS rates were 98.6 and 98.4% in non-postoperative RT and postoperative RT groups, respectively (p = 0.858). The univariate analyses also confirmed that the administration of postoperative RT was not associated with better BCSS (p = 0.858).

Conclusion

The incidence of breast cancer-related death is probably sufficiently low to avoid postoperative RT in women aged ≥65 years with TC of the breast after BCS.

Invasive lobular carcinoma of the breast: A special histological type compared with invasive ductal carcinoma

The clinical outcomes and therapeutic strategies for infiltrating ductal carcinoma (IDC) and infiltrating lobular carcinoma (ILC) are not uniform. The primary objectives of this study were to identify the differences in the clinical characteristics and prognoses between ILC and IDC, and identify the high-risk population based on the hormone receptor status and metastasis sites. The Surveillance, Epidemiology, and End Results Program database was searched and patients diagnosed with ILC or IDC from 1990 to 2013 were identified. In total,796,335 patients were analyzed, including 85,048 withILC (10.7%) and 711,287 withIDC (89.3%). The ILC group was correlatedwith older age, larger tumor size, later stage, lower grade, metastasis disease(M1) disease, and greater counts ofpositive lymph nodesandestrogen-receptor-positive (ER)/progesterone receptor-positive (PR) positive nodes. The overall survival showed an early advantage for ILC but a worse outcome after 5 years. Regarding the disease-specific survival, the IDC cohort had advantages over the ILC group, both during the early years and long-term. In hormone status and metastasis site subgroup analyses, the ER+/PR+ subgroup had the best survival, while the ER+/PR- subgroup had the worst outcome, especially the ILC cohort. ILC and IDC had different metastasis patterns. The proportion of bone metastasis was higher in the ILC group (91.52%) than that in the IDC (76.04%), and the ILC group was more likely to have multiple metastasis sites. Survival analyses showed patients with ILC had a higher risk of liver metastasis (disease-specific survival[DSS]; P = 0.046), but had a better overall survival than the bone metastasis group (P<0.0001). We concluded that the long-term prognosis for ILC was poorer than that for IDC, and the ER+/PR- subgroup had the worst outcome. Therefore, the metastasis pattern and prognosis must be seriously evaluated, and a combination of endocrine therapy and chemotherapy should be considered.