Case Report: Metastatic Signet-Ring-Cell Carcinoma of the Bladder From Breast Invasive Lobular Carcinoma Detected by Computed Tomography

Abstract

Secondary bladder tumors are relatively rare among all bladder tumors, while bladder metastases from breast cancer have been rarely reported. Furthermore, signet-ring differentiation may appear in the metastases from a breast invasive lobular carcinoma regardless of whether the primary breast tumor had signet-ring cells, which may cause diagnostic uncertainty. We report a case of a 55-year-old female patient with diffuse bladder thickening as the chief complaint and no specific clinical manifestations. While the cystoscopy showed multiple scattered red protuberances, the biopsy suggested signet-ring-cell carcinoma. The gastroscopy results suggested poorly differentiated adenocarcinoma with signet-ring cells. Considering the patient's history of invasive lobular carcinoma of the breast, chronic myeloid leukemia, and metastatic endometrial carcinoma from the breast, we performed an immunohistochemical analysis and the results indicated that signet-ring-cell carcinomas of the stomach and bladder originated from the invasive lobular carcinoma of the breast. We performed positron emission tomography/computed tomography and the results showed that there were multiple bone metastases already present. This was the first English case report of invasive lobular carcinoma of the breast metastasizing to the uterus, stomach, bladder, and bones with multiple signet-ring-cell variations. This study shares our reasons for misdiagnosing and opinions on diagnosing and treating for this kind of cases.

Keywords: CT manifestations; bladder carcinoma; breast invasive lobular carcinoma; case report; clinical diagnosis; metastasis; multiple cancers; signet-ring-cell carcinoma.

Figure 1

The representative staining results of endometrial carcinoma [(A) H&E, ×200; (B) estrogen receptor, ×200; (C) progesterone receptor, ×200; (D) GATA-3, ×200].

Figure 2

(A) The bladder wall thickened (August, 2020); (B) The bilateral ureter was slightly dilated (August, 2020); (C) The bladder wall was significantly thickened (March, 2021); (D) Hydronephrosis in the right kidney (March, 2021); (E) The bladder wall was significantly thicker than before (May, 2021); (F) Hydronephrosis in bilateral kidneys (May, 2021); (G) The bladder wall was still thick (September, 2021); (H) Hydronephrosis was slightly less than before (September, 2021).

Figure 3

(A) Left ureteral opening. Bladder wall was locally thickening without new organisms (August, 2020); (B) Right ureteral opening (August, 2020); (C) Small red protuberances could be seen around left ureteral opening (May, 2021); (D) Right ureteral opening could not be seen (May, 2021); (E) Left ureteral opening (September, 2021); (F) Small red protuberances on bladder wall; right ureteral opening could not be seen (September, 2021).

Figure 4

The representative staining results of bladder carcinoma [(A). H&E, ×200; (B) CDX-2, ×200; (C) CK20, ×200; (D) GATA-3, ×200; (E) Villin, ×200]; The representative staining results of gastric carcinoma [(F) H&E, ×200; (G) CDX-2, ×200; (H) CK20, ×200; (I) GATA-3, ×200; (J) Villin, ×200; (K) estrogen receptor, ×200; (L) progesterone receptor, ×200; (M) E-cadherin, ×200].