New Research Targets Breast Cancer Diagnosis and Treatment

ORLANDO—A series of clinical studies presented at the 52nd Annual Cancer Symposium of the Society of Surgical Oncology (SSO) addressed various aspects of breast cancer diagnosis, staging, and treatment.

MRI in Occult Breast Cancer

Modified radical mastectomy is the accepted treatment in occult breast cancer, based on the assumption that isolated axillary metastases must reflect the presence of a primary tumor somewhere. However, in one-third of women with occult breast cancer, no tumor is found in mastectomy specimens. John A. Olson, Jr., MD, of Memorial Sloan-Kettering Cancer Center, reported that modified magnetic resonance imaging (MRI) can prevent many of those unnecessary mastectomies.

Dr. Olson and his colleagues reviewed records of 40 women with biopsy-proven metastatic axillary lymph nodes, occult primary cancer, and negative physical examination and mammography. Results of MRI with and without gadolinium were compared with pathologic findings in 34 patients.

Tumors were identified in 95% of specimens from patients who were MRI positive but in only 1 of 5 patients who were MRI negative. Dr. Olson noted that there is room for improvement, since one of the five MRI-negative patients actually had a tumor, but he concluded that “MRI identifies most occult breast cancer and facilitates breast conservation.”

Preop Chest X-Rays Add Little

Routine chest x-rays add little to preoperative staging in clinical stage I or stage II breast cancer and should be used only in patients in whom metastasis is suspected, Gregory A. Carlson, MD, reported. Dr. Carlson and his colleagues at the Baystate Medical Center, Springfield, Massachusetts, found that preoperative chest x-rays had changed management in only one of 1,571 such patients treated at that institution.

“These procedures represent an unnecessary cost and should be reserved for patients with other indications of underlying disease,” Dr. Carlson concluded. He estimated that dropping these routine x-rays could save $18 million annually nationwide.

Skin-Sparing Mastectomy

Skin-sparing mastectomies facilitate immediate breast reconstruction, give better cosmetic results (see Figure), and are well accepted by patients. Rache Simmons, MD, reported that they are also as safe as other approaches.

Dr. Simmons and her colleagues at Cornell Medical Center, New York, compared outcomes in 77 patients who had skin-sparing mastectomies with those of 154 patients who had non-skin-sparing mastectomies.

There were no significant differences in local recurrence rates, distant recurrence rates, local recurrence-free survival at 5 years, or distant recurrence-free survival at 5 years.

However, Dr. Simmons pointed out two possible study biases: Patients referred for skin-sparing mastectomy tended to be younger, and median follow-up for the newer technique was 15.6 months vs 32.4 months for patients treated with other types of mastectomy surgery.

Immediate Reconstruction

There has been concern that immediate breast reconstruction might jeopardize outcomes for patients with locally advanced breast cancer by delaying subsequent chemotherapy. Lisa Newman, MD, reported that immediate breast reconstruction can be done with low morbidity in patients with locally advanced disease and does not increase local or distant relapse rates.

Dr. Newman and her colleagues at the University of Texas M.D. Anderson Cancer Center compared postoperative management and outcomes in 50 patients with locally advanced breast cancer who had modified radical mastectomies and immediate reconstruction with those of 72 patients undergoing mastectomy without immediate reconstruction.

The median interval between surgery and postoperative chemotherapy was 35 days for those having immediate breast reconstruction vs 21 days for those who did not. Dr. Newman described this difference as “marginally significant”

(P = .05). It did not appear to be clinically important, since there were no significant differences in local or distant relapse rates. However, 7 of the 15 patients receiving immediate reconstruction with implants (47%) required subsequent implant extractions because of contractures or infections. Thus, Dr. Newman stressed that immediate reconstruction in this setting should be performed with autogenous tissue.

Patients who have had carcinoma in one breast have an elevated risk of cancer in the contralateral breast and may consider contralateral prophylactic mastectomy as a preventive measure. Leslie Montgomery, MD, of Memorial Sloan-Kettering Cancer Center, reported results of a study incorporating data from the National Prophylactic Mastectomy Registry, developed at Memorial Sloan-Kettering. At the time of the report, the registry included 817 women who had undergone prophylactic (unilateral or bilateral) mastectomy.

The results show that most women undergoing unilateral prophylactic mastectomy have no regrets. Only 18 of 296 patients (6%) who had undergone contralateral prophylactic mastectomy reported that they regretted having had the procedure.

“To minimize the risk of regrets in women who are contemplating contralateral prophylactic mastectomy, it is imperative that these women be counseled regarding an estimation of the risk of contralateral breast cancer, the possible alternatives to contralateral prophylactic mastectomy, and the efficacy of prophylactic mastectomy,” Dr. Montgomery advised.