Papillary carcinoma in situ

To describe a new international dataset for pathology reporting of ductal carcinoma in situ (DCIS), variants of lobular carcinoma in situ (LCIS) and low grade lesions (encapsulated papillary carcinoma, solid papillary carcinoma in situ, Paget's disease) produced by the International Collaboration on Cancer Reporting (ICCR).

The ICCR, a global alliance of pathology bodies, uses a rigorous and efficient process for the development of evidence-based, structured datasets for pathology reporting of common cancers. Their aim is to support quality pathology reporting and engender understanding between breast surgeon, pathologist and oncologist for optimal and uniform patient management globally. Here we describe the dataset for DCIS, some variants of LCIS (namely the pleomorphic and the florid variants) and low grade lesions by a multidisciplinary panel of internationally recognised experts. The agreed dataset comprises 12 core (required) and 5 non-core (recommended) elements suitable for both developed and low-income jurisdictions, derived from a review of current evidence. Areas of contention have been addressed using a pragmatic approach in the absence of evidence. Use of all core elements is the minimum reporting standard for any individual case. Commentary is provided, explaining each element's clinical relevance, definitions to be applied where appropriate for the agreed list of value options and the rationale for considering the element as core or non-core.

This first internationally agreed dataset for DCIS, variants of LCIS and low grade lesions reporting will enable their standardisation of pathology reporting and enhance clinicopathological communication leading to improved patient outcomes. Widespread adoption will also facilitate international comparisons, multinational clinical trials and help to improve the management of breast disease globally.

We aimed to investigate mammography (MG), ultrasound (US), and magnetic resonance imaging (MRI) findings of papillary breast carcinoma subtypes and to compare the diagnostic features and performance of the imaging method in distinguishing subtypes.

Forty-two patients presenting with pathological diagnosis of 45 papillary carcinoma lesions, between 2014 and 2019, were included. Cases were assigned to five subgroups according to the latest World Health Organization (WHO) classification. The clinical characteristics (n = 45) and imaging features of each pathological subgroup were retrospectively related to imaging findings from US (n = 45), MG (n = 37), and breast MRI (n = 23), and further compared.

The finding of a palpable mass in all subgroups was more common than nipple discharge on clinical breast evaluation, and no significant difference was found between the subgroups. Irregular shape on MG (10/12, 83.3%, p = 0.039) and US (11/12, 91.7%, p = 0.039) was found more frequently in invasive micropapillary carcinoma (IMPC) compared to other subgroups. Circumscribed margins (4/5, 80%, p = 0.002) occurred more frequently in papillary ductal carcinoma in situ (pDCIS) and encapsulated papillary carcinoma (EPC) than in other subgroups (6/8, 75%, p = 0.002). Lower apparent diffusion coefficient (ADC) values were found in solid papillary cancer (SPC) than in other subgroups (ADC = 0.35 x 10^-3, p = 0.017).

Radiological findings of papillary carcinomas overlap with each other. US and MRI are complementary when revealing specific morphological characteristics.

Background Intraductal papillomas (IDPs) are typically classified as B3 lesions in histology as they may show intralesional heterogeneity with a potential upgrade to malignancy. On core needle biopsy (CNB), a distinction between papilloma versus papillary ductal carcinoma in situ (DCIS) may be difficult. It is well known that otherwise benign papillomas may harbor foci of atypical ductal hyperplasia or DCIS. In this study, we aimed to calculate the radiological (mammogram and ultrasound) accuracy of IDP and to analyze the accuracy of CNB to diagnose IDP. Furthermore, we calculated the percentage of upgrade to malignancy after surgical excision. Any case that had a co-existing in-situ or invasive carcinoma during surgical excision was considered as an "upgrade" to malignancy. Finally, we analyzed the current management protocol for IDP in the institution and suggested changes, if needed. Methodology This is a retrospective cross-sectional study. A total of 112 cases diagnosed as IDP radiologically and/or by histopathology over a one-year time frame were included. A retrospective analysis of the accuracy of the radiological diagnosis was done by comparing it with CNB and/or surgical excision biopsy reports. The number of cases diagnosed with a co-existing in-situ or invasive carcinoma was calculated. This was considered as an "upgrade" from a B3 lesion in CNB to carcinoma in surgical excision. Current institutional management protocols were evaluated and compared with international benchmarks. Results Out of the 112 cases, 91 were suspected to be papilloma by imaging. The remaining 21 cases who were positive for papilloma on biopsy but were not diagnosed radiologically were also studied separately. Among the biopsied patients, eight were positive for IDP with atypia in CNB. Five out of these eight cases had an in-situ or invasive component during the surgical excision, with one invasive lobular carcinoma, three lobular carcinomas in situ, and one DCIS on surgical excision histopathology. The upgrade percentage was calculated to be 22.72%. Conclusions Due to the large upgrade potential of IDP, it is recommended to biopsy every radiologically suspected lesion and excise pathology-proved lesions. If the biopsy shows papilloma without atypia, vacuum excision is sufficient; otherwise, surgical excision with a clearance of margins is advocated. Annual mammograms/surveillance is recommended for biopsy-proven cases. IDP has a high upgrade potential, and, hence, care should be taken to biopsy suspicious lesions. An excision of biopsy-proven lesions must be done.