Breast cancer metastasis to the GI tract may mimic primary gastric cancer

Covert Breast Cancer Metastasis to the Gastrointestinal Tract: Is Extra Vigilance Needed?

Breast cancer (BC) is a common cancer in females. Spread to the gastrointestinal tract is rare. This is a 61-year-old woman with history of T2N0M0 lobular BC treated 5 years earlier. She underwent endoscopic evaluation for new-onset anemia and was found to have multiple gastric ulcers, a normal-appearing duodenum, and subtle colonic nodules. Targeted and random biopsies of abnormal and normal findings, respectively, showed adenocarcinoma with diffuse immunohistochemical staining compatible with her BC history. This highlights the importance of maintaining a high suspicion index in patients with lobular BC and the utility of random biopsies in such cases.

Gastric metastasis and peritoneal carcinosis revealing primary breast cancer: an unusual presentation

Breast cancer is the most frequent cancer among women. Gastrointestinal tract metastases are uncommon and might be misidentified as primary carcinoma.A noteworthy case-study involved 53-year-old-woman complaining from epigastric pain, ascites and overall health decline. Initial investigations were inconclusive, prompting laparoscopic peritoneal biopsies which revealed independent cell proliferation. Subsequently, a second look upper digestive endoscopy showed multiple gastric ulcerations suggestive of gastric carcinoma. Histologic examination confirmed independent cell proliferation with estrogen receptors expression, a characteristic feature of breast carcinoma. Further investigations led to bilateral invasive lobular breast carcinoma diagnosis. Epirubicin cycophosphamide was prescribed after progression under letrozole ribocilib therapy.This case aims to raise awareness among clinicians about the importance of ruling out breast cancer in patients with peritoneal carcinosis and paying attention to digestive symptoms in breast cancer patients with careful gastric endoscopic examination to avoid misdiagnosis.

The clinicopathological and immunohistochemical features of breast carcinomas with signet-ring-cell differentiation

BACKGROUND

This study investigated the clinicopathological features, immunophenotypic characteristics and differential diagnosis of primary breast carcinomas with signet ring cell differentiation, as well as differences in the traits of signet ring-like cell mucin.

METHODS

A total of five cases of primary breast cancer diagnosed with signet ring cell differentiation and treated at The First People's Hospital of Jingmen from January 2016 to December 2021 were collected. HE, immunohistochemical staining, and AB-PAS staining were used for the analysis.

RESULTS

Although we strictly selected all the primary breast cancer cases with signet ring cell differentiation, there were differences in the arrangement of the cells and the grading of nuclei. Our immunohistochemical results showed that the ER was consistently strongly positive, and the PR expression was not consistent, while all the cases of HER2 were negative. CK7 was negative in one case, and CK20 and CK5/6 were not expressed in all the cases. The mucin MUC1 was positive and showed two patterns. MUC2 was strongly positive in all the cases. All the cases were negative for CDX2, SATB2, PAX8, TTF-1, and Napsin A, while the positive expression of COX2, Villin, and WT-1 was not constant. One case expressed neuroendocrine markers. The expression level of Ki67 was between 10 and 30%. AB (pH 2.5)-PAS staining revealed that the intracellular mucus contained more cells with neutral mucus, while the extracellular mucus was mainly acidic.

CONCLUSION

We found that histological morphology, cell morphology, and nuclear grading differentiate among different cases. The immunohistochemical characteristics of primary breast cancers diagnosed with signet ring cell differentiation are helpful for identification. The differences in the expression patterns of mucins may be related to unfavorable clinicopathological factors, but their usefulness as a prognostic marker remains to be further understood. The heterogeneity of cell mucus, the differentiation of tumor cells, and the phenotypic changes of tumors also need further study.

Metastatic gastric cancer from breast carcinoma presenting with paraneoplastic rheumatic syndrome: A case report

BACKGROUND

Breast cancer is the most frequently diagnosed cancer worldwide. It is the leading cause of death by malignant disease in women.

CASE SUMMARY

A female patient, 73 years of age, sought care due to weakness, mild abdominal pain, arthralgia, and weight loss. She was taking anastrazole as maintenance therapy for localized breast cancer and had moderate anemia and elevated acute-phase markers. Upper digestive endoscopy showed isolated erosion in the gastric corpus. This lesion was compatible with signet-ring cell adenocarcinoma in anatomopathological study and was confirmed as metastasis of a breast carcinoma in immunohistochemistry, which was positive for estrogen antibody. Further imaging studies determined numerous proximal bone metastases. The patient was treated with prednisone for paraneoplastic syndrome, which improved the anemia and rheumatic disease, and with chemotherapy, which greatly improved the symptoms. She has been followed-up for 6 mo, and her anemia, arthralgias, and acute phase markers have normalized.

CONCLUSION

Systemic treatment strategies seem to be the best choice for gastric metastasis from breast cancer, resulting in disease control and relapse-free survival. Prospective studies with longer follow-up are needed to better understand the biological, pathological, and clinicopathological characteristics and outcomes of the endoscopic features associated with metastatic gastric cancer from breast carcinoma.

Delayed and Synchronous Recurrence of Breast Cancer Metastases in Multiple Organs

The most common sites of breast cancer metastasis include the lymph nodes, bones, lungs, liver, and brain. Gastrointestinal tract metastasis is rarely seen, and hypopharyngeal metastasis is extremely rare. We herein report a case of late distant recurrence of breast cancer and synchronous metastasis to the hypopharynx, stomach, ileum, bones, and lymph nodes almost 24 years after surgery. To our knowledge, this is the first case of synchronous metastasis to the hypopharynx, gastrointestinal tract, and other organs, especially after a long interval following primary mastectomy.

Gastric metastases of breast cancer: Histopathological and molecular characterization of a single Institution case series

The metastatic spread of breast carcinoma to the stomach is a rare event and often represents a diagnostic challenge. In the present study, 23 cases of gastric metastases from breast cancer were retrospectively identified dating back until 2007. Primitive histotype, localization, gross appearance, microscopic architecture were analyzed. Cytokeratins 7 and 20, sex hormones, HER2 and Ki67 expression was evaluated. According to the results, the series was characterized by an enrichment of lobular primitive histotype (43.7%). In most cases gastric metastases were described as parietal nodules, polypoid masses or ulcerated lesions, mainly involving the antro-angular region. In a relatively high rate (10.5%) of cases, endoscopic examinations resulted negative for macroscopic lesions. More than half of the cases (52.2%) microscopically resembled primitive poorly cohesive gastric cancer. Because gross and histological findings can be deceiving, immunohistochemistry may be essential for the diagnosis of gastric metastases from breast cancer. Accordingly with the results of our analysis and literature review, an immunohistochemical panel composed of cytokeratins 7 and 20, Estrogen and Progesteron Receptors would drastically improve diagnostic accuracy. Interaction among the clinician, endoscopist and the pathologist is also essential to provide the patient the best therapeutic option.

Gastrointestinal metastatic signet ring cell breast cancer in young females: a case report

BACKGROUND

Signet ring cell carcinoma (SRCC) is characterized by strong invasiveness and rapid progression. It occurs mostly in young and middle-aged patients, and early patients may have no clinical symptoms. Gastric SRCC with breast cancer metastasis is relatively rare. It often presents challenges for clinicians and pathologists and may lead to an absolutely different therapeutic strategy.

CASE DESCRIPTION

In this paper, we report on a 37-year-old woman who was admitted to the hospital with a left breast mass discovered 5 days earlier, the mass was occasionally painful, and there was no skin swelling, skin depression, or other abnormalities. The initial diagnosis considered her to have a left breast tumor. The patient was previously healthy with no family history of tumor. Considering the possibility of malignant lesions, she underwent resection of the left breast tumor and surrounding tissue. Postoperative pathological findings suggested SRCC (left breast mass). Although the patient had no history of gastrointestinal tumors, considering that SRCC can also appear in the gastrointestinal tract and other organs. We performed gastroscopy on the patient, showed an ulcerative mass in the greater curvature of the gastric body, with irregular nodular uplift of the surrounding mucosa. The excised breast lesions were analyzed by immunohistochemistry, and the pathological result showed SRCC (left breast tumor). Combined with the results of immunohistochemistry, it was consistent with gastrointestinal metastasis. Through our multi-faceted differential diagnosis, the final diagnosis of the patient was clear, which not only bought time for the patient's subsequent treatment, but also avoided misdiagnosis and blind treatment due to the particularity and rarity of the case.

CONCLUSIONS

Gastric cancer should be considered when breast tumors show SRCC without in situ lesion. Signet ring cell gastric cancer (occult) should be excluded even if the patient has no family history of gastric cancer. It is important to distinguish metastatic cancer from primary breast cancer to avoid misdiagnosis and blind treatment due to the particularity of the case, at which point an early recognition can be made and an optimal treatment plan can be chosen.

Diagnostic utility of the combined use of HNF4A and GATA3 in distinction between primary and metastatic breast and gastric carcinomas

Sometimes the distinction between gastric adenocarcinomas and breast carcinomas can be challenging. Hepatocyte nuclear factor 4-alpha (HNF4A) has been suggested as a potential marker in these cases. The aim of the present work was to evaluate the role of the combined use of HNF4A and GATA3 as immunohistochemical markers in distinction between primary and metastatic breast and gastric carcinomas. This retrospective study was conducted on (81) cases divided into four groups of cohorts: primary BC (cohort I, n = 25), primary GC (cohort II, n = 23), and metastases derived from both types of tumors designated as metastasis derived from BC (cohort III-A, n = 17) and metastasis derived from GC (cohort III-B, n = 16). We performed immunohistochemistry analysis of HNF4A and GATA3 in all (81) cases. HNF4A expression was seen in 22 of 23 primary gastric adenocarcinomas and was absent in all 25 primary breast carcinomas (sensitivity 95.7%, specificity 100%). HNF4A was seen in 15 of 16 metastatic gastric adenocarcinomas and was absent in all 17 metastatic breast carcinomas (sensitivity 93.8%, specificity 100%). GATA3 showed 92 and 88% sensitivity, and 95.7 and 100% specificity for primary breast carcinomas and metastatic breast carcinomas, respectively. Our data confirmed the potential utility of HNF4A as a diagnostic marker and can be used as an adjunct to GATA3 as an immunohistochemical panel to differentiate between breast and gastric carcinomas.

Metastatic Breast Lobular Carcinoma to Unusual Sites: A Report of Three Cases and Review of Literature

Invasive lobular carcinoma of the breast is the second most common type of invasive breast carcinoma. Invasive lobular carcinoma has an unusual pattern of metastases, which poses a diagnostic challenge for both clinicians and pathologists. We herein present three cases of breast invasive lobular carcinoma presented with metastasis to unusual sites, namely, uterus, colon and stomach. We recommend a higher index of suspicion in any case with breast cancer developing gastrointestinal tract or genital tract symptoms.

Breast carcinoma metastasising to the gastric wall and the peritoneum: what physicians need to know

Breast cancer is the most common cancer among women in the USA and rarely metastasises to the gastric wall. We present a case of a 69-year-old woman with medical history of stage II-B breast cancer who presented with epigastric abdominal pain and black tarry stools. CT scan of the abdomen showed moderate gastric wall thickening and ascites. The patient underwent an esophagogastroduodenoscopy (EGD) with endoscopic ultrasound (EUS) for a fine-needle biopsy, which was negative for malignancy. Based on her presentation, we kept a high index of suspicion for peritoneal carcinomatosis and malignancy. The patient underwent laparoscopic wedge resection of the gastric wall with biopsies of gastric wall and peritoneum. Both biopsies confirmed the diagnosis of metastatic invasive lobular breast carcinoma. Our case highlights the importance of diagnostic laparoscopy and EUS in the setting of negative EGD biopsy results with a high suspicion of breast cancer metastasis to gastric wall.

A 58-Year-Old Woman with Acute Gastric Perforation Due to Metastatic Ductal Carcinoma 18 Years Following Bilateral Mastectomy for Invasive Ductal Carcinoma of the Breast

Patient: Female, 58-year-old

Final Diagnosis: Gastric perforation

Symptoms: Abdominal pain • peritonitis

Medication: —

Clinical Procedure: Jejunostomy tube placement • laparoscopic surgery • open surgery

Specialty: Surgery

Perforating duodenal ulcer with umbilical herniation as a metastatic complication of primary signet ring cell carcinoma of the breast

Primary signet ring cell carcinoma (SRCC) of the breast is extremely rare, and the associated patterns of metastatic dissemination poorly described. Here, we report the case of a 61-year-old woman presenting with acute abdominal pain. Esophagogastroduodenoscopy revealed a non-bleeding erosive gastropathy, which was biopsied and found significant for a poorly differentiated, GATA3-positive SRCC. The patient was lost to follow up until re-presenting 6 months later with a perforating duodenal ulcer and umbilical herniation. Biopsies of umbilical hernia sack contents were significant for an estrogen receptor (ER) positive SRCC, and breast examination identified a right breast mass significant for an ER positive lobular carcinoma with signet ring features, thereby affirming the diagnosis of metastatic SRCC of the breast. This case offers insight into an advanced form of a rare clinical entity, and suggests that staining for breast markers such as GATA3 should be considered for all biopsies significant for SRCC.

Rare common bile duct metastasis of breast cancer: A case report and literature review

BACKGROUND

Breast cancer is the most common tumor in women, and about one-third of cases develop metastatic disease. However, metastatic breast cancer rarely invades the common bile duct (CBD) directly without involving the liver, and involvement of the gastrointestinal tract is rare. Cases of such metastases pose a particular diagnostic challenge.

CASE SUMMARY

A 55-year-old female presented to the Department of Gastroenterology with complaint of a 2 mo history of right upper abdominal pain accompanied by pain in the right back, aggravated after eating greasy diet. The patient had received a diagnosis of breast cancer 3 years prior. Physical examination showed obvious superficial protuberant erythema on the left neck and chest skin, with slight tenderness and burning sensation. Endoscopic retrograde cholangiopancre-atography showed an obstruction at the end of the CBD. Histopathology of the CBD and symptomatic skin biopsies showed positivity for cytokeratin 7 and trans-acting T-cell-specific transcription factor breast cancer biomarkers. A cancer embolus was also found in the skin vasculature. Accordingly, the diagnosis of breast cancer metastases to the skin and biliary ducts was made. A plastic biliary sent was placed, which relieved the right upper abdominal pain and protected against unnecessary hepatectomy surgery.

CONCLUSION

Although rare, biliary metastasis should be considered in patients with bile duct stenosis and a history of breast cancer.

Clinical Characteristics and Prognosis of Gastrointestinal Metastases in Solid Tumor Patients: A Retrospective Study and Review of Literatures

Background

According to the literature and our experience, patients with gastrointestinal metastases are relatively rare. Numerous case reports and literature reviews have been reported. We present one of the larger case series of gastrointestinal metastases.

Objectives

To explore the clinical characteristics and prognosis of patients with gastrointestinal tract metastases, which are rare metastatic sites.

Methods

Patients with gastrointestinal metastases in the setting of stage IV primary carcinomas treated at Beijing Ditan Hospital and Peking University International Hospital from November 1992 to August 2017 were included in this study. The diagnosis of gastrointestinal tract metastases was based on histopathology.

Results

30 patients (median age 56 years, 56.7% female) were included. The most common primary carcinomas associated with gastrointestinal metastases were breast (11 patients, 36.7%), stomach (9 patients, 30.0%), and lung (4 patients, 13.3%) cancer. The major pathological types were adenocarcinoma (16 patients, 53.3%) and ductal carcinoma (9 patients, 30.0%). Ten patients (33.3%) underwent local gastrointestinal treatment, and 20 patients (66.7%) underwent nonlocal treatment (involving chemotherapy alone or best supportive care). For breast cancer patients and gastric cancer patients who underwent local therapy, a significant survival advantage was observed (p = 0.001 and p = 0.012, respectively). The presence of other common metastases was identified as an independent poor prognostic factor through multivariate analysis with a HR (hazard ratio) of survival of 0.182 (95% confidence interval (CI) 0.11-0.523, p = 0.031).

Conclusion

Gastrointestinal metastases are most frequently from breast invasive ductal carcinoma. The presentation of other common metastases with gastrointestinal metastasis indicates poor prognosis, and selected patients may benefit from surgical intervention.

Perforated gastric carcinomatosis following invasive lobular cancer of the breast

Current guidelines do not advocate a routine search for gastric metastasis in known patients of breast cancer. This makes it challenging to suspect them clinically as they progress over many years. Gastric carcinomatosis from primary invasive lobular cancer can perforate leading to life-threatening abdominal emergency necessitating surgery.

Differentiating breast carcinoma with signet ring features from gastrointestinal signet ring carcinoma: assessment of immunohistochemical markers

Signet ring morphology is recognized throughout the gastrointestinal tract. However, this pattern may be observed in other primary sites giving rise to diagnostic challenges in the work-up of metastases. Relatively newer immunohistochemical markers have not been evaluated in this context. We assessed expression patterns of several common immunohistochemical markers in tumors with Signet ring morphology to delineate a pragmatic approach to this differential diagnosis. Primary breast and gastrointestinal carcinomas showing Signet ring features were reviewed. Non-mammary and non-gastrointestinal tumors with this morphology were included for comparison. Estrogen receptor (ER), progesterone receptor (PR), E-cadherin, CK7, CK20, GCDFP-15, mammaglobin, CDX2, GATA-3, and HepPar-1 immunohistochemistry was performed. Expression patterns were compared between breast and gastrointestinal tumors as well as lobular breast and gastric tumors. Ninety-three cases were identified: 33 breast carcinomas including 13 lobular, 50 gastrointestinal tumors including 23 gastric, and 10 from other sites. ER (sensitivity=81.8%, specificity=100%, positive predictive value (PPV)=100%, negative predictive value (NPV)=89.3%) and GATA-3 (sensitivity=100%, specificity=98%, PPV=96.8%, NPV=100%) expression were associated with breast origin. CK20 (sensitivity=66.7%, specificity=93.3%, PPV=94.1%, NPV=63.6%) and CDX2 (sensitivity=72%, specificity=100%, PPV=100%, NPV=68.9%) demonstrated the strongest discriminatory value for gastrointestinal origin. These markers exhibited similar discriminatory characteristics when comparing lobular and gastric signet ring carcinomas. In a limited trial on metastatic breast and gastric cases, these markers successfully discriminated between breast and gastric primary sites in 15 of 16 cases. ER and GATA-3 are most supportive of mammary origin and constitute an effective panel for distinguishing primary breast from primary gastrointestinal Signet ring tumors when combined with CK20 and CDX2 immunohistochemistry.

Metastatic gastric cancer from breast carcinoma: A report of 78 cases

The metastatic spread of breast carcinoma to the stomach is rare. There are a small number of previous studies that report metastases from the breast to the stomach and these provide limited information regarding this infrequent event. Consequently, the clinicopathological features, clinical outcomes and the optimal treatment for these patients remain to be elucidated. In the present study, 78 cases of gastric metastases from breast cancer, including the current case, were identified from previous studies between 1960 and 2015. The clinicopathological features of primary breast tumors and metastatic gastric lesions, including initial stage, tumor size, hormone receptor status, treatment modalities and overall survival (OS) rate, were analyzed. The patients were all female and the median age at the time of gastric metastasis diagnosis was 59 years old (range, 38–86 years). The majority of the patients initially presented with stage II breast cancer (35.9%) and abdominal pain was the most common symptom of gastric metastases (75.6%). A total of 51/78 patients (65.4%) were identified to have a history of invasive lobular breast carcinoma and the majority of gastric tumors were positive for hormonal receptors and human epidermal growth factor receptor 2 (HER-2) negative (estrogen receptor, 94.0%; progesterone receptor, 68.3%; HER-2, 5.9%). Furthermore, in the univariate analysis, multiple organs involved prior to or at the time of gastric metastases were diagnosed and multiple gastric lesions and peritoneal carcinomatosis were significantly correlated with OS. Additionally, salvage hormonal therapy, but not surgery or chemotherapy, significantly extended OS. However, in the multivariate analysis, metastasis prior to stomach involvement was the only independent indicator of poor OS. In conclusion, physicians must be vigilant when patients with breast cancer history present with gastrointestinal symptoms, despite gastric metastasis from breast cancer being rare. An appropriate systemic therapeutic strategy that includes hormonal therapy may be beneficial for this group of patients.

The Clinical Significance of Occult Gastrointestinal Primary Tumours in Metastatic Cancer: A Population Retrospective Cohort Study

Purpose

The purpose of this study was to estimate the incidence of occult gastrointestinal (GI) primary tumours in patients with metastatic cancer of uncertain primary origin and evaluate their influence on treatments and overall survival (OS).

Materials and Methods

We used population heath data from Manitoba, Canada to identify all patients initially diagnosed with metastatic cancer between 2002 and 2011. We defined patients to have “occult” primary tumour if the primary was found at least 6 months after initial diagnosis. Otherwise, we considered primary tumours as “obvious.” We used propensity-score methods to match each patient with occult GI tumour to four patients with obvious GI tumour on all known clinicopathologic features. We compared treatments and 2-year survival data between the two patient groups and assessed treatment effect on OS using Cox regression adjustment.

Results

Eighty-three patients had occult GI primary tumours, accounting for 17.6% of men and 14% of women with metastatic cancer of uncertain primary. A 1:4 matching created a matched group of 332 patients with obvious GI primary tumour. Occult cases compared to the matched group were less likely to receive surgical interventions and targeted biological therapy, and more likely to receive cytotoxic empiric chemotherapeutic agents. Having an occult GI tumour was associated with reduced OS and appeared to be a nonsignificant independent predictor of OS when adjusting for treatment differences.

Conclusion

GI tumours are the most common occult primary tumours in men and the second most common in women. Patients with occult GI primary tumours are potentially being undertreated with available GI site-specific and targeted therapies.

BREAST CANCER METASTASIS IN THE STOMACH: WHEN THE GASTRECTOMY IS INDICATED ?

Background:

Breast cancer is the most common malignant neoplasm in the female population. However, stomach is a rare site for metastasis, and can show up many years after initial diagnosis and treatment of the primary tumor.

Aim:

Analyze a case series of this tumor and propose measures that can diagnose it with more precocity.

Methods:

Were analyzed 12 patients with secondary gastric tumors. Immunohistochemistry has demonstrated that primary tumor was breast cancer. We retrieved information of age, histological type, interval between diagnosis of the primary breast cancer and its metastases, immunohistochemistry results, treatment and survival.

Results:

The mean age was 71.3 years (ranging 40-86). Ten cases had already been underwent mastectomy in the moment of the diagnosis of gastric metastasis. Two patients had diagnosis of both primary and secondary tumors concomitantly. At average, diagnosis of gastric metastasis was seven years after diagnosis of primary breast cancer (ranging 0-13). Besides, nine cases had also metastases in other organs, being bones the most affected ones. Immunohistochemistry of the metastases has shown positivity for CK7 antibody in 83.34%, estrogen receptor in 91.67%, progesterone receptor in 66.67% and AE1AE3 antibody in 75%, considering all 12 cases. Moreover, CK20 was absent significantly (66.67%). The positivity of BRST2 marker did not present statistical significance (41.67%). Eight cases were treated with chemotherapy associated or not with hormonal blockade. Surgical treatment of gastric metastasis was performed in four cases: three of them with total gastrectomy and one with distal gastrectomy. Follow-up has shown a mean survival of 14.58 months after diagnosis of metastasis, with only two patients still alive.

Conclusion:

Patients with a history of breast cancer presenting endoscopic diagnosis of gastric cancer it is necessary to consider the possibility of gastric metastasis of breast cancer. The confirmation is by immunohistochemistry and gastrectomy should be oriented in the absence of other secondary involvement and control of the primary lesion.

Lobular carcinoma of the breast with gastrointestinal metastasis

We present the case of a 74-year-old woman with metastatic lobular carcinoma with an occult breast primary presenting as a suspected ampullary tumor due to its ampullary metastasis. The patient's clinical presentation is of interest in two aspects. First, lobular carcinoma of the breast metastatic to the ampulla is extremely rare. Second, in the absence of a detectable primary lesion, prior history of malignancy, or distinguishing clinical, radiological, and endoscopic features, histopathological assessments are pivotal for arriving at the appropriate diagnosis and for optimizing treatment.

Breast cancer metastasis to the stomach confirmed using gastroscopy: A case report

Breast cancer metastasis to the stomach is relatively rare. Unlike infiltrating ductal carcinoma, invasive lobular carcinoma (ILC) has a high tendency to metastasize to the stomach. The present study reports a case of a 53-year-old female who had undergone a modified radical mastectomy of the left breast for ILC eight years previously and presented at the clinic seeking treatment for epigastric discomfort from sour regurgitation and belching that had persisted for one month. Gastroscopy revealed multiple apophysis lesions in the stomach, which were diagnosed as metastatic tumors to the stomach. The diagnosis was further established using histological and immunohistochemical analyses for gross cystic disease fluid protein-15, cytokeratin (CK) 7 and CK20. The patient was treated with systemic chemotherapy without surgery. During the treatment, two gastroscopy procedures revealed that the apophysis lesions in the gastric body had narrowed significantly. Few cases of breast cancer metastasizing to the stomach have been reported, particularly those that have been confirmed using gastroscopy. The present study reports a case of breast cancer metastasis to the stomach to raise awareness of the condition.

Extruded highly proliferative benign mucous neck cells: a peculiar histologic mimic of poorly cohesive gastric carcinoma

Histologic mimics of poorly cohesive gastric carcinoma are uncommon but are important for pathologists to recognize. Here we report 2 cases of a novel histologic pattern mimicking poorly cohesive gastric carcinoma. In both cases, light microscopy revealed sheets of discohesive epithelial cells with prominent mitoses that have high proliferative activity, with a Ki67 proliferation index greater than 70%. One case was diagnosed as poorly cohesive carcinoma at an outside hospital and the other was referred in consultation as atypia of undetermined significance. Reexamination of the hematoxylin-eosin slides revealed morphologic clues that these sheets of discohesive cells represent artifactual extrusion of the highly proliferative neck zone from the surrounding benign mucosa. In contrast to poorly cohesive cancer, this artifact lacks all of the following diagnostic features: nuclear atypia, signet ring cell morphology, and intercellular stroma with infiltrating single cells between glands. Eight and 14 months later, both patients remain cancer free.