Study: New study questions favorability of rare form of breast cancer
In patients with mucinous carcinoma, a distinctive tumor that reportedly has a very favorable prognosis, a minimally effective therapy that includes no additional treatment post-surgical removal should be reconsidered as researchers have made a link between this rare breast cancer and multiple tumors undetected by mammography or ultrasound.
George Perkins, MD, associate professor of the department of radiation oncology at the University of Texas M.D. Anderson Cancer Center in Houston and colleagues presented the findings of the review at the CTRC-AACR San Antonio Breast Cancer Symposium last week.
"While mucinous breast cancer is thought to be a disease with a favorable prognosis, our study is the first to identify it as one associated with significant multifocal presentation--a potentially unfavorable aspect with a subtype long thought to be extremely favorable," explained Perkins. "Our findings must caution those caring for these women that they may not only need more radiographic evaluation, such as MRI, but also intraoperative collaboration with radiology and pathology. These patients also may need standard radiation treatment, rather than the minimal effective therapy.”
According to the authors, this rare form of breast cancer, also known as also known as colloid carcinoma (accounting for approximately two percent of all diagnosed breast cancer cases) has been thought by researchers to have a better prognosis than other invasive breast cancers. However, research for this cancer has been limited by short follow-up periods and small patient-populations.
The researchers used a sample size of 264 patients, presenting with a pure mucinous carcinoma diagnosis at M.D. Anderson from 1965 to 2005. Eighty-six percent of the patients involved in the study, ranging in age from 25-89 years, were at stage T2 or less. The median follow-up for the patients was approximately 14 years.
The authors found that of the 44 percent of the women who received breast-conserving therapy, and the rest who underwent a mastectomy, 51 percent of all patients received radiation.
Initially, 10 percent of all patients had presented with multifocal disease. However, after a complete pathological review and resection, a rate of 38 percent of all patients were found to have multifocal disease. Moreover, none of these occult tumors were detected by mammography and/or ultrasound.
At the five-year follow-up mark, overall survival rates, disease-free survival and local-regional control were 95 percent, 88 percent, and 83 percent. At the 10-year mark, rates increased to 97 percent for overall survival, 95 percent for disease-free survival and 92 percent for local-regional control. The 15-year mark saw rates of 97 percent, 94 percent and 85 percent, for overall survival, disease-free survival and local-regional control, respectively.
Surgical options presented no difference in trends in overall overall survival, disease-free survival or overall survival. However, improved rates for local-regional control were noted by the authors in patients who had undergone radiation post-surgery to those that had not.
“It's imperative that we continue to research personalized treatment options for this subtype and that patients receive their treatment based on actual presentation rather than the assumption that this is always a favorable disease," Perkins said.
Other plans for follow- up to this study by Perkins and colleagues will include the evaluation of a subtype of mucinous breast cancer thought to be exceedingly aggressive in hopes of establishing specific screening and treatment guidelines.
George Perkins, MD, associate professor of the department of radiation oncology at the University of Texas M.D. Anderson Cancer Center in Houston and colleagues presented the findings of the review at the CTRC-AACR San Antonio Breast Cancer Symposium last week.
"While mucinous breast cancer is thought to be a disease with a favorable prognosis, our study is the first to identify it as one associated with significant multifocal presentation--a potentially unfavorable aspect with a subtype long thought to be extremely favorable," explained Perkins. "Our findings must caution those caring for these women that they may not only need more radiographic evaluation, such as MRI, but also intraoperative collaboration with radiology and pathology. These patients also may need standard radiation treatment, rather than the minimal effective therapy.”
According to the authors, this rare form of breast cancer, also known as also known as colloid carcinoma (accounting for approximately two percent of all diagnosed breast cancer cases) has been thought by researchers to have a better prognosis than other invasive breast cancers. However, research for this cancer has been limited by short follow-up periods and small patient-populations.
The researchers used a sample size of 264 patients, presenting with a pure mucinous carcinoma diagnosis at M.D. Anderson from 1965 to 2005. Eighty-six percent of the patients involved in the study, ranging in age from 25-89 years, were at stage T2 or less. The median follow-up for the patients was approximately 14 years.
The authors found that of the 44 percent of the women who received breast-conserving therapy, and the rest who underwent a mastectomy, 51 percent of all patients received radiation.
Initially, 10 percent of all patients had presented with multifocal disease. However, after a complete pathological review and resection, a rate of 38 percent of all patients were found to have multifocal disease. Moreover, none of these occult tumors were detected by mammography and/or ultrasound.
At the five-year follow-up mark, overall survival rates, disease-free survival and local-regional control were 95 percent, 88 percent, and 83 percent. At the 10-year mark, rates increased to 97 percent for overall survival, 95 percent for disease-free survival and 92 percent for local-regional control. The 15-year mark saw rates of 97 percent, 94 percent and 85 percent, for overall survival, disease-free survival and local-regional control, respectively.
Surgical options presented no difference in trends in overall overall survival, disease-free survival or overall survival. However, improved rates for local-regional control were noted by the authors in patients who had undergone radiation post-surgery to those that had not.
“It's imperative that we continue to research personalized treatment options for this subtype and that patients receive their treatment based on actual presentation rather than the assumption that this is always a favorable disease," Perkins said.
Other plans for follow- up to this study by Perkins and colleagues will include the evaluation of a subtype of mucinous breast cancer thought to be exceedingly aggressive in hopes of establishing specific screening and treatment guidelines.