Primary signet ring cell carcinoma of the breast: A rare entity with unique biological behavior-A clinical study based on pure signet ring cell carcinoma cohort

The "Forgotten" Subtypes of Breast Carcinoma: A Systematic Review of Selected Histological Variants Not Included or Not Recognized as Distinct Entities in the Current World Health Organization Classification of Breast Tumors

Breast carcinoma is the most common cancer in women. Nineteen different subtypes of breast carcinomas are recognized in the current WHO classification of breast tumors. Except for these subtypes, there are a number of carcinomas with special morphologic and immunohistochemical features that are not included in the 5th WHO classification, while others are considered special morphologic patterns of invasive breast carcinoma of no special type. In this manuscript, we systematically review the literature on four different subtypes of invasive breast carcinoma, namely lymphoepithelioma-like breast carcinoma, breast carcinoma with osteoclast-like giant cells, signet-ring breast carcinoma, and metaplastic breast carcinoma with melanocytic differentiation. We describe their clinicopathological characteristics, focusing on the differential diagnosis, treatment, and prognosis.

Gastrointestinal signet ring cell malignancy: current advancement and future prospects

Globally, gastrointestinal cancer is the most widespread neoplastic disease and the primary contributor to cancer-associated fatalities. Gastrointestinal signet ring cell carcinoma (SRCC) exhibits unique distinguishing features in several aspects when compared to adenocarcinomas (ACs). The scarcity of signet ring cell carcinoma has resulted in a heightened significance of related clinical and molecular investigations. However, a comprehensive and systematic review of the clinical, molecular, therapeutic, and research aspects of this disease is currently absent. This review provides an overview of the latest developments in our understanding of the clinical and molecular features of gastrointestinal signet ring cell carcinoma (SRCC). Additionally, we have compiled a list of potential therapeutic targets or biomarkers, as well as an examination of the current treatment options and the possible mechanisms of formation.

Invasive lobular carcinoma with extracellular mucin (ILCEM): clinicopathologic and molecular characterization of a rare entity

Invasive lobular carcinoma with extracellular mucin (ILCEM) is a rare histologic subtype of breast cancer. Little is known about the pathologic or genomic signatures that distinguish ILCEM from classic invasive lobular carcinoma (ILC) or mucinous carcinoma. We studied 17 breast cancers with lobular morphology and extracellular mucin. Thirteen tumors with sufficient tissue for DNA extraction were analyzed by a next generation sequencing (NGS) assay that interrogates 447 genes for mutations and copy number variations (CNVs). Median patient age was 66 yrs (range: 31-77 yrs). Sixteen patients presented with masses, 7 of which were >2 cm. Seven patients had lymph node metastases. The cases of ILCEM were moderately (n = 13) or poorly differentiated (n = 4), frequently exhibiting variant morphology that has not been previously described or emphasized, including grade 3 nuclei (n = 11), diffuse signet ring cells (n = 10), solid growth (n = 4), tumor necrosis (n = 3) or apocrine features (n = 2). All tumors showed absent or reduced membranous E-cadherin expression. Concurrent lobular carcinoma in situ (LCIS) was seen in 11/17 cases, 1 of which was a striking example of signet ring cell LCIS with extracellular mucin. Receptor profiles were ER+/HER2- (n = 15) and ER+/HER2+ (n = 2). With a median follow-up of 83.5 months (range: 3-171 months) in 12 patients with available information, 8 patients had recurrences resulting in 4 cancer-related deaths. The most common CNVs were 16q loss (n = 11) and 1q gain (n = 9). CDH1 gene-level alterations were detected in all but one case, including frameshift (n = 7), nonsense (n = 2), and donor splice site (n = 1) mutations and indels (n = 2). Recurrent mutations were also seen in PIK3CA (n = 3), POLQ (n = 3), TP53 (n = 3), ERBB3 (n = 3), ERBB2 (n = 2), and RUNX1 (n = 2). Genes with recurrent amplifications included GATA3 (n = 4), FOXA1 (n = 3), CCND1 (n = 2). Our data highlights ILCEM as a distinct variant of ILC that often presents with higher-grade and variant morphologic features and is associated with an aggressive clinical course. NGS data support an overall lobular-type molecular profile and reveal potentially targetable alterations in a subset of cases with recurrence.

Immunohistochemical analysis of PD-L1 and tumor-infiltrating immune cells expression in the tumor microenvironment of primary signet ring cell carcinoma of the prostate

Primary signet ring cell carcinoma (SRCC) of the prostate is a rare neoplasm. However, its potential tumorigenic mechanism, clinicopathological features, and prognostic outcome have not been systematically described. To determine the pathogenic mechanism, we detected distributions of programmed cell death-ligand 1 (PD-L1), programmed death 1 (PD-1), and cellular components in the tumor microenvironment, including tumor-infiltrating lymphocytes (CD4 and CD8), tumor-associated macrophages (TAMs; CD163 and CD68), and tumor-associated fibroblasts (vimentin and alpha-smooth muscle actin [α-SMA]), in tumor tissues from four patients with primary prostatic SRCC compared with corresponding adjacent tissues and tumor tissues from 30 patients with prostate adenocarcinoma (PCa) by immunohistochemical staining. We found higher expression of PD-L1, CD163, and CD68 in primary SRCC specimens than that in both corresponding adjacent nontumor specimens and PCa specimens with different Gleason scores, indicating that TAMs may participate in the malignant biological behavior of primary SRCC of the prostate. For further analysis, we searched electronic journal databases and Surveillance, Epidemiology, and End Results (SEER) to identify 200 eligible patients including our four cases. According to Kaplan–Meier survival curve analysis, patients <68 years old, with radical prostatectomy (RP), Gleason score of 7–8, and lower clinical stage had longer overall survival (OS). Moreover, Cox multivariate analysis indicated that race (hazard ratio [HR] = 1.422), surgical approach (HR = 1.654), and Gleason score (HR = 2.162) were independent prognostic factors for OS. Therefore, primary SRCC of the prostate represents a distinct and aggressive subtype of prostate cancer associated with a higher distribution of PD-L1 and TAMs, which warrants further clinical investigation.

Prognostic Analysis of Primary Breast Signet Ring Cell Carcinoma and Mucinous Breast Adenocarcinoma: A SEER Population-Based Study

Background

Primary breast signet ring cell carcinoma (SRCC) is a rare type of breast cancer with typical morphological characteristics, high aggressiveness, and poor prognosis. SRCC is different from mucinous breast adenocarcinoma (MBC). However, only a few studies have explored the clinicopathological features and prognosis of SRCC and MBC.

Methods

Data retrieved from the Surveillance, Epidemiology, and End-Results (SEER) database (2004-2015) were used to explore the prognostic effect of clinicopathological features and treatment modalities on survival outcomes of SRCC and MBC patients. Kaplan-Meier plot analysis, multivariate Cox proportional risk model, propensity score matching (PSM), and subgroup analysis were performed.

Results

A total of 167 patients with SRCC and 11,648 patients with MBC were included in the study. SRCC patients exhibited higher histological grade (p < 0.001), larger tumor volume (p < 0.001), higher rate of lymph node metastasis (p < 0.001), and higher frequency of distal metastasis (p < 0.001) compared with MBC patients. Cox proportional hazards regression analysis showed that SRCC patients had lower overall survival (OS) and breast cancer-specific survival (BCSS) compared with MBC patients. Subgroup survival analysis showed that the SRCC patients had lower OS and BCSS in subgroups including younger than 60 years old, white race, married, without chemotherapy, and received radiotherapy compared with the MBC patients in these subgroups. In addition, the SRCC patients had lower BCSS in subgroups including other races (including Asian or Pacific Islander and American Indian/Alaska Native), without surgery, and lymph node metastasis.

Conclusion

The findings showed that primary breast SRCC patients have unique clinical characteristics and worse prognosis compared with MBC patients. Notably, different treatment methods resulted in different prognosis for SRCC and MBC types; therefore, SRCC patients should be distinguished from MBC patients to improve efficacy of treatment.

Metastatic Breast Signet-Ring Cell Carcinoma from a Colonic Primary: Review of a Rare Case Report

Introduction: Colonic signet-ring cell carcinoma is a distinctive rare subtype of adenocarcinoma with a predilection for early metastasis. Among the rare extramammary metastatic adenocarcinomas to the breast, colonic signet-ring cell carcinomas constitute a small percentage. The distinction of a primary from a secondary breast signet ring cell carcinoma is indispensable since it may result in different therapeutic approaches. Here we presented a rare case of metastatic breast signet-ring cell carcinoma from a rectal origin and review its distinctive histopathologic features. Case Presentation: A 37-year-old woman presented with a breast mass 3 months after undergoing low anterior resection surgery to remove a rectal mass, diagnosed as signet ring cell carcinoma. Histopathologic examination of the core needle breast mass biopsy revealed tumor cells with signet-ring cell cytomorphology. The performed immunohistochemistry confirmed carcinoma of colonic origin. Conclusions: Colorectal signet-ring cell carcinoma is a rare and aggressive tumor. Its metastatic spread is most seen in the intra-abdominal area, with seldom reported cases of breast metastasis. Histologically, it can mimic a primary breast carcinoma, especially if no prior history of colonic origin exists. Accurate diagnosis is important since these 2 entities carry different therapeutic management. Proper immunophenotyping, obtaining a thorough clinical history and imaging studies facilitate a correct diagnosis.

Clinicopathological characteristics and prognosis of signet ring cell carcinoma of the gallbladder

Background

Signet ring cell carcinoma (SRC) is a rare histological subtype of gallbladder adenocarcinoma. The current study evaluates the clinicopathologic features and prognosis of SRC.

Methods

Patients with adenocarcinoma of the gallbladder were identified in the Surveillance, Epidemiology, and End Results database from 1973 to 2016. Overall survival (OS) and cancer-specific survival (CSS) of patients who had SRC were compared with those of patients who had non-SRC using Cox regression and propensity score methods.

Results

Of 22,781 gallbladder adenocarcinomas retrieved, 377 (1.7%) were SRC and the other 22,404 were non-SRC. SRC was more significantly associated with older age, female gender, poor differentiation, advanced tumor stage, lymph node metastasis, distant metastasis, and advanced AJCC stage. The 5-year OS and CSS in the SRC group were 7.2 and 6.5%, respectively, both of which were significantly worse than the 13.2 and 13.3% seen in the SRC group (P = 0.002 and P = 0.012, respectively). This survival disadvantage persisted in multivariable analyses [hazard ratio (HR) = 1.256, P = 0.021 and HR = 1.211, P = 0.036] and after propensity score matching (OS: HR = 1.341, P = 0.012 and CSS: HR = 1.625, P = 0.005). Surgery in combination with chemotherapy improved OS of gallbladder SRC patients compared with surgery alone (HR = 0.726, P = 0.036) or chemotherapy alone (HR = 0.433, P < 0.001).

Conclusion

Patients with SRC of the gallbladder have distinct clinicopathological features with poor prognosis. Surgery in combination with chemotherapy can improve survival.

Primary signet-ring cell carcinoma of the lung in an HIV-positive patient

Primary lung signet-ring cell carcinomas are a rare entity and only a few cases of pure signet-ring cell carcinomas of the lung are reported in the English literature. They usually have an aggressive behavior and a poor prognosis because in most cases they are identified at an advanced stage. We present a unique case of primary signet-ring cell carcinoma of the lung because the patient was HIV positive, a heavy smoker, and also the tumor, discovered incidentally during chest x-ray, was a pure type of signet-ring cell carcinoma. Surgical therapy associated with chemoradiotherapy represents the gold standard in the care of these patients.