Devin P. Puapong, Surgical Resident, Department of Surgery; Raquel Goldhardt, Surgical Resident, Department of Surgery; Scott E. Lentz, Staff Surgeon, Department of Gynecologic Oncology; Najeeb S. Alshak, Chief, Department of Pathology and Laboratory; Maher A. Abbas, Chief, Section of Colon and Rectal Surgery, Kaiser Permanente Los Angeles, Los Angeles, CA
Devin P. Puapong, MD
Department of Surgery
Raquel Goldhardt, MD
Department of Surgery
Scott E. Lentz, MD
Department of Gynecologic
Najeeb S. Alshak, MD
Department of Pathology
and Laboratory Medicine
Maher A. Abbas, MD
Section of Colon and
Los Angeles, CA
Introduction: Breast cancer is one of the leading causes of death among women. Although metastatic spread of breast cancer to the abdomen and pelvis has been reported, metastatic disease to the rectum is unusual.
Discussion: This paper discusses the case of a breast and ovarian cancer patient who presented with an isolated, late metastasis to the rectum that was treated with en bloc low anterior resection. Histological evaluation revealed a poorly differentiated adenocarcinoma of the breast metastatic to the wall of the rectum, consistent with the patient's primary breast carcinoma. The authors review the literature and discuss breast cancer metastasis and its associated outcomes.
Conclusion: Invasive ductal carcinoma of the breast metastasizes most commonly to the bones, lungs, liver, and brain; however, metastasis to the abdomen and pelvis is possible and should not be overlooked. The case reported in this paper was particularly complicated because of the patient's history of ovarian cancer and the possibility that the mass was a recurrence of the ovarian cancer. A longer median survival has been reported in abdominal and pelvic metastases patients who have received optimal debulking, and in those who experience an initial disease-free interval greater than 5 years before recurrence.
Breast cancer is a common malignancy in women and most frequently metastasizes to the bones, lungs, liver, and brain. Metastatic disease to the pelvis is rare, with a reported rate of 0.5%, and most cases involve the adnexae.1-5 We report a case of invasive ductal carcinoma metastasizing to the wall of the rectum in a patient with a history of breast and ovarian cancer. Because of the location of the mass, recurrent ovarian cancer was suspected. Histopathology revealed the mass to be a poorly differentiated adenocarcinoma of the breast metastatic to the wall of the rectum. We discuss metastatic disease from breast cancer and the factors that affect patient prognosis.
A 40-year-old woman with a history of breast and ovarian cancer presented for routine post-treatment follow-up. Her stage IIB breast cancer had been diagnosed 10 years earlier. She underwent mastectomy and received postoperative adjuvant chemotherapy at that time. Seven years later, the patient developed stage IIIA ovarian cancer (Figure 1), which was treated with neoadjuvant chemotherapy, abdominal hysterectomy, bilateral salpingo-oophorectomy, and debulking of omental and peritoneal implants. The patient remained healthy and had no clinical or radiographic evidence of disease for an additional 3 years. She then developed constipation, and rectovaginal examination noted a fixed, smooth, anterolateral rectal mass 6 cm from the anal verge. Colonoscopy revealed the mass to be submucosal without mucosal involvement. Computed tomography (CT) scanning showed a 5-cm extraluminal rectal mass and no evidence of metastatic disease (Figure 2). Her carcinoembryonic antigen level was normal, but her CA125 level was elevated at 526 U/mL (normal, <35 U/mL). The clinical and imaging findings were suspicious for recurrent ovarian cancer localized to the pelvis; there was no evidence of distant disease. The patient was advised to undergo surgical resection.
Exploration of her abdomen and pelvis revealed a localized pelvic tumor emanating from the anterior rectal wall, without evidence of carcinomatosis. An en bloc low anterior resection was performed, which included a portion of the posterior vaginal wall to ensure negative margins. A primary stapled end-to-end colorectal anastomosis was performed without fecal diversion. Histopathologic evaluation of the surgical specimen revealed ductal carcinoma of the breast metastatic to the rectal wall (Figure 3). Lymphovascular infiltration was noted, and three lymph nodes were positive for metastatic disease. The tumor histology, including negative estrogen and progesterone receptor status and negative overexpression of HER2/neu, were identical to the patient's primary breast cancer.
The patient's postoperative course was uneventful and she was discharged from the hospital 4 days later. She underwent postoperative radiation therapy to the pelvis and received systemic chemotherapy. At 3-month follow-up, she showed no evidence of recurrent disease clinically (CA125 level, 22 U/mL) or radiographically on bone and CT scans (Figure 4).
Metastatic disease from invasive ductal carcinoma of the breast usually involves the bones, lungs, liver, and brain, and involvement of the gastrointestinal tract is rarely encountered. Invasive lobular carcinoma of the breast, however, is known to metastasize to the gastrointestinal and genitourinary tracts in addition to the peritoneum and retroperitoneum.3-5 We could identify no other reports in the literature of a ductal breast cancer that metastasized solely to the rectum.
In this particular case, it is important to note that our patient's presentation with ovarian cancer and ascites was complicated by her history of breast cancer. Her abdomen was explored only after she exhibited a near complete response to empiric chemotherapy directed against epithelial ovarian carcinoma. Because she had received chemotherapy preoperatively, the histologic diagnosis of ovarian carcinoma could not be made conclusively, and it was unclear whether her ovarian cancer was of breast or ovarian origin.
Recurrence of advanced ovarian carcinoma is almost universal, which is why our patient's rectal mass was suspected to be of ovarian origin. Clinical complete response to therapy is associated with a 1-year recurrence rate of 50% and a 2-year recurrence rate of 80%.6,7 Treatment of recurrent disease is largely determined by the patient's disease-free interval. Multiple authors have found statistically significant survival advantages associated with a disease-free interval greater than 12 months.6,7 The lengthy disease-free interval between our patient's primary ovarian cancer therapy and the presentation of the isolated rectal mass made a surgical approach favorable, even though her lesion turned out to be metastatic breast cancer.
The overall rate of pelvic metastases in patients with breast cancer is relatively low. Drotman and colleagues reviewed the pelvic CT scans of 2,426 breast cancer patients; the scans were taken over a 9-year period.1 Only 17 patients (0.5%) were found to have pelvic metastases, of which 11 cases were isolated to bone, 5 were adnexal, and 1 had multiple sites of involvement (bones, adnexa, and endometrium). The majority of patients in the study (65%) had an initial diagnosis of invasive ductal carcinoma.
Treatment of recurrent ovarian disease is largely determined by the patient's disease-free interval.
Abu-Rustum and colleagues reviewed breast cancer patients who underwent laparoscopy or laparotomy over a 15-year period.2 In this cohort of 821 patients, 59 (7%) had metastatic disease to the abdomen or pelvis. Of these patients, 42 (71%) had adnexal or endometrial involvement, 7 (12%) had bone metastases, 5 (8.5%) had liver involvement, and the remaining 5 (8.5%) had multiple metastatic sites. In the subgroup of 59 patients with abdominal or pelvic metastases, 43 (73%) had an initial diagnosis of invasive ductal carcinoma. Similar to our case, the majority of these patients (69%) had positive axillary lymph nodes and underwent adjuvant chemotherapy (90%) after the breast cancer was diagnosed. Following debulking surgery, patients with no gross residual disease survived longer than those who had grossly positive margins, with a median survival period of 36 months and 20 months, respectively. Furthermore, when the time from initial diagnosis to recurrence exceeded 5 years, the median survival after recurrence was longer (36 months vs 17 months for recurrence diagnosed before 5 years).
In cases of early onset breast cancer, genetic mutations (namely BRCA1 and BRCA2) must be considered and genetic counseling should be encouraged.
Our patient was found to have recurrent metastatic disease 10 years after the initial breast cancer diagnosis. We were able to achieve grossly negative margins and the patient was referred for pelvic radiotherapy followed by chemotherapy because of the poor histologic features of her tumor. Additionally, because of her age at initial presentation and strong family history of breast cancer, the patient had been previously referred for genetic counseling. In cases of early onset breast cancer, genetic mutations (namely BRCA1 and BRCA2) must be considered and genetic counseling should be encouraged.
Although rare, ductal carcinoma of the breast can metastasize to the abdomen and pelvis. Based on our literature search, this case represents the first published report of an isolated metastasis to the rectum originating from an invasive ductal carcinoma of the breast diagnosed 10 years earlier. Resection of all gross recurrent disease can offer prolonged survival in some patients.
The authors have no relationship with any commercial entity that might represent a conflict of interest with the content of this article and attest that the data meet the requirements for informed consent and for the Institutional Review Boards.