Contrast-enhanced computed tomography detection of occult breast cancers presenting as axillary masses

Evaluation of the usefulness of breast CT imaging in delineating tumor extent and guiding surgical management: a prospective multi-institutional study

OBJECTIVE

The aim of the present study was to evaluate the usefulness of computed tomographic (CT) imaging in delineating tumor extent and guiding surgical management.

BACKGROUND

The routine use of preoperative magnetic resonance imaging (MRI) is a controversial issue in breast cancer management. Negative studies with regard to the utility of MRI might be due to differences in positioning during imaging and subsequent surgery.

METHODS

Candidates for breast-conserving surgery were eligible for the study. The surgeons marked the line of planned excision on the skin, which was also recorded on the CT image. Contrast-enhanced breast CT was performed in the supine surgical position. The CT results were used to help determine the extent of resection. The pathological findings were then compared with the CT-guided surgical plans.

RESULTS

A total of 297 patients were involved. The surgeons widened the extent of resection in 42 (14.1%, 95% confidence interval 10.1%-18.1%) patients on the basis of the CT findings. Among the 6 patients whose procedures were changed to mastectomy, 4 had pathologically multicentric tumors and 2 had widely spread intraductal components. The remaining 36 patients underwent quadrantectomy instead of wide excision on the basis of the CT images. There were 3 patients in whom conversion from wide excision to quadrantectomy resulted in overexcision. Preoperative breast CT may have reduced the positive margin rate and also correctly changed the extent of surgery in 13.1% of patients.

CONCLUSIONS

This prospective study suggests that breast CT, carried out in the supine position, is useful in the preoperative determination of the optimal surgical procedure.

Two cases of occult breast cancer in which PET-CT was helpful in identifying primary tumors

We report two cases of occult breast cancer in which masses were completely nonpalpable and positron emission tomography-computed tomography (PET-CT) was extremely helpful in identifying the primary tumor. Case 1 involved a 56-year-old woman with enlarged lymph nodes 3 cm in size in the axilla. Based on excisional biopsy, axillary lymph node metastasis of breast cancer was suspected but an obvious primary tumor in the breast was not identifiable on mammography, contrast-enhanced CT, or ultrasonography. Faint accumulation of fluorodeoxyglucose (FDG) was noted only on PET-CT, so the site was considered to be the primary site, and operation was performed. As a result of postoperative pathological examination, ductal carcinoma in-situ (DCIS) was diagnosed. Case 2 involved a 55-year-old woman with enlarged lymph nodes 3 cm in size in the axilla. Based on the excisional biopsy, axillary lymph node metastasis of breast cancer was suspected. In this case as well, an obvious primary tumor was not identifiable with palpation or mammography. On PET-CT, faint accumulation of FDG was noted in the vicinity of the CD regions, or upper and lower outer quadrants. When contrast-enhanced CT and ultrasonography were performed, a faint nodular opacity less than 1 cm in size corresponding to this site was found and diagnosed as the primary site, operation was subsequently performed. Pathologic diagnosis indicated invasive cancer. PET-CT is a helpful option for the diagnosis of occult breast cancer with primary sites that conventional imaging studies have difficulty identifying.

The role of computed tomography in the selection of breast cancer treatment

Contrast-enhanced computed tomography (CE-CT) is one of the most sensitive imaging modalities. CE-CT plays a role in the following: (1) to determine the extent of breast cancer to select the appropriate breast conserving treatment (BCT). The sensitivity and specificity for the detection of extensive intraductal component (EIC) by CE-CT were 82-88% and 75-89%, respectively. The pathological extent of tumors significantly correlated with the extension revealed by CE-CT; (2) to determine the extent of resection following neoadjuvant chemotherapy, which is difficult to assess by other modalities; (3) to diagnose axillary lymph node metastasis. The sensitivity and specificity are 79-90% and 70-89%, respectively; (4) to identify occult breast cancer with axillary metastasis and to diagnose local recurrence after BCT.

Occult breast carcinoma presenting with axillary lymph node metastases: follow-up of eleven patients

BACKGROUND

Breast carcinoma presenting with axillary metastases and no clinically apparent primary tumor in the breast is an uncommon form of stage IIdisease. The methods of diagnosis and treatment of these patients are not established. We present our eleven treated cases of occult carcinoma and discuss the issues of evaluation and management.

METHODS

Eleven patients with occult breast carcinoma (OBC) presenting between January, 1985 and April, 1998 at the National Shikoku Cancer Center were evaluated clinically and with immunohistochemical staining. Immunohistochemical staining was performed using the Envision method. The primary antibodies for gross cystic disease fluid protein-15 (GCDFP-15), estrogen receptor (ER) and progesterone receptor (PR) were used.

RESULTS

Nine patients underwent mastectomy. Breast-conserving surgery was performed in one patient. One patient did not receive any operation for the breast. No primary tumor was found among three of nine cases receiving mastectomy. Some adjuvant therapies after the operation were performed in eight cases. Follow-up ranged from 5 to 310 months (median, 54 months), and the five-year disease free survival rate was 62.5%. There were eight GCDFP-15 positive cases (72.7%) and four ER and/or PR positive cases (36.4%).

CONCLUSIONS

GCDFP-15 is useful for confirming the primary site of breast carcinoma. Ultrasonography, computed tomography, and magnetic resonance imaging are thought to be good for detecting occult primary tumors. The incidence of OBC is still unclear, but it is possible that these patients need to be treated as typical stage II patients.

Treatment of noninvasive carcinoma: fifteen-year results at the National Cancer Center Hospital in Tokyo

The introduction of screening mammography (MMG) will lead to increased detection of preclinical early breast cancer in Japan. It has become more important to understand the nature of these lesions. We tried to elucidate the long term prognosis and clinical and pathological characteristics of noninvasive cancers. A total of 336 (5.4%) ductal carcinoma in situ (DCIS) and 32 (0.5%) lobular carcinoma in situ (LCIS) were diagnosed in 6 277 breast carcinomas at the National Cancer Center Hospital from 1962 to 1995. Most (80%) LCIS occurred in premenopausal women. LCIS has significantly higher bilaterality than that of DCIS. Local recurrence occurred in approximately 10% of patients after breast conserving surgery for DCIS and LCIS. Four patients died of breast carcinoma, which were initially diagnosed as noninfiltrating carcinoma. The 15-year cause specific survival rates of patients with DCIS and LCIS were 98.5 % and 100 %, respectively.