Unexpected destination! Rectal carcinoma metastasis to breast

Breast mass as the first sign of metastasis from rectal carcinoma: a case report and review of the literature

We present a case report of a 41-year-old woman who developed a left breast mass 18 months after undergoing Dixon rectal cancer surgery. The purpose of this case report is to highlight the possibility of breast metastases in patients with colorectal cancer and emphasize the importance of careful evaluation and follow-up as well as timely and accurate diagnosis and management of the metastatic disease. During the physical examination in 2021, we noted that the lower border of the mass was 9 cm from the anal verge and that it occupied approximately one-third of the intestinal lumen. A pathological biopsy revealed the mass in the patient's intestinal lumen was a rectal adenocarcinoma. The patient underwent Dixon surgery for rectal cancer and received subsequent chemotherapy. The patient had no prior history of breast-related medical conditions or a family history of breast cancer. During the current physical examination, we discovered multiple lymphadenopathies in the patient's left neck, bilateral axillae, and left inguinal region, but none elsewhere. We observed a large erythema of about 15x10 cm on the patient's left breast, with scattered hard nodes of varying sizes. Palpation of the area beyond the upper left breast revealed a mass measuring 3x3 cm. We conducted further examinations of the patient, which revealed the breast mass and lymphadenopathy on imaging. However, we did not find any other imaging that had significant diagnostic value. Based on the patient's conventional pathology and immunohistochemical findings, combined with the patient's past medical history, we strongly suspected that the patient's breast mass was of rectal origin. This was confirmed by the abdominal CT performed afterward. The patient was treated with a chemotherapy regimen consisting of irinotecan 260 mg, fluorouracil 2.25 g, and cetuximab 700 mg IV drip, which resulted in a favorable clinical response. This case illustrates that colorectal cancer can metastasize to unusual sites and underscores the importance of thorough evaluation and follow-up, particularly when symptoms are atypical. It also highlights the importance of timely and accurate diagnosis and management of metastatic disease to improve the patient's prognosis.

Breast Metastasis From Rectal Signet-Ring Cell Carcinoma: A Case Report and Review of Literature

BACKGROUND

Metastatic rectal cancer (mRC) of the breast is an extremely rare clinical situation. There are few reported cases in domestic or foreign literature. The clinicopathologic characteristics along with the diagnostic and therapeutic strategies of such cases remain relatively unclear. Here, we would like to provide our comprehensive insights into this rare entity.

METHODS

We present a case that till now is the first reported breast metastasis from rectal cancer pathologically diagnosed as a signet-ring cell carcinoma, and we review the current literature on this rare event. The detailed clinical data, histopathology, management, and follow-up aspects were gathered for analysis.

RESULTS

A total of 15 cases were collected including the current case. Breast metastases from rectal cancer present at an average age of 47.7 years (range, 28 to 69 years) and appear with an average interval of 28.4 months (range, 5 months to 18 years) following primary tumor diagnoses. Of the 15 cases, 8 and 5 are pathologically diagnosed as adenocarcinomas and mucinous adenocarcinomas, respectively. Most cases (11/15) are accompanied by extramammary metastases. About half of the breast metastases (7/15) were to the left. In all cases, the main complaints were palpable mass. The average maximum diameter of the metastatic mass is 2.7 cm (range, 1-11 cm). The majority (8/12) of cases with accessible therapy information exclude the option of local surgery.

CONCLUSION

Previous cancer history and accurate immunohistochemistry data play critical roles to distinguish mammary metastasis from a primary neoplasm of the breast. Mastectomy and molecular-targeted drugs should be considered with priority if systemic condition supports them.

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.

Rare case of a male breast tumour secondary to poorly differentiated rectal adenocarcinoma

Rectal cancer metastasis to the breast is rare. A case history is presented of a 57-year-old man with breast metastases from rectal carcinoma. However, this patient did not have metastasis in common metastatic sites, such as the liver, lung, and other organs. The patient had undergone chemotherapy for advanced rectal carcinoma 6 months earlier and presented with a mammary mass. An ultrasound-directed core needle biopsy of the breast mass was performed. Cytology indicated an adenocarcinoma with poor to moderate differentiation in the breast mass Immunohistochemistry (IHC) showed cytokeratin (CK) expression with a pattern that is characteristic of colorectal tumours: CK7(−), CK20(+), CDX2(−), Villin(+) TOPOII(−), and a Ki-67 index of 30%. The 3 main breast tumour markers were negative. Based on these histopathological and immunohistochemical findings, the patient was diagnosed with breast metastases from rectal carcinoma. Distant metastasis should be taken into account when a patient has a medical history of rectal adenocarcinoma, even when a rare metastasis site is involved. We should be vigilant when patients have some features that are favorable for metastasis. Histopathological characteristics and immunohistochemical tests are helpful for diagnosis. Regardless of surgical treatment after neoadjuvant chemotherapy, standard chemotherapy regimens for intestinal tumors, and EGFR molecular-targeted drugs, there is no obvious effect and the prognosis is poor. The treatment method needs further study.