There are about 140,000 women diagnosed annually with early breast cancer in the United States. For these women, most are going to be eligible for at least one or two or more of these local therapy options including lumpectomy plus whole breast irradiation, lumpectomy plus brachytherapy, lumpectomy alone, mastectomy alone or mastectomy plus reconstruction. When patients receive local therapy that’s concordant with guidelines our feeling is that their survival is excellent and essentially equivalent regardless of the local therapy chosen. However, these local therapies differ significantly in the extent of surgery and radiation that is delivered.
As another point of background, mastectomy rates in the United States have been increasing for early breast cancer and this is a study that was published earlier this year in JAMA Surgery using data from the National Cancer Database. They reported that nearly 40% of women with early breast cancer in the United States were treated with mastectomy and that the proportion of women treated with mastectomy increased substantially between 2005 and 2011. Then of these women who underwent mastectomy, approximately 40% underwent post-mastectomy breast reconstruction and the use of post-mastectomy breast reconstruction in the United States also increased significantly over this time frame.
There are multiple reasons why a woman may choose to have a mastectomy over a lumpectomy; there are certainly medical indications such as multifocality or multicentricity or the presence of a heritable genetic syndrome. But recent literature also indicates that patient fears and misperceptions often drive the choice for mastectomy. Notably absent is the concept of value when making determinations about the best local therapy for women with early breast cancer.
In light of this background, our primary objective was to improve the understanding of the relative value of local treatment options for early breast cancer by comparing their complication burden, total cost, complication related cost and non-complication cost. To do this we assembled two unique non-overlapping cohorts. We used a large commercially available database called the MarketScan Commercial Claims and Encounters Database. This captures younger patients, under the age of 65, with private insurance at the time of diagnosis and this is simply an amalgamation of claims, there’s no cancer information directly in this database. In addition we used the SEER Medicare data to study older patients aged 66 and older at the time of diagnosis. This is a population based data source which links Medicare claims to tumour registry data abstracted by registrars whose data ultimately flows to the National Cancer Institute. This represents approximately 26% of the United States population.
One of our primary outcomes was the presence of any complication and to define these complications we assembled this set of ICD9 and CPT codes to reflect the common complications that one might see after local therapy for early breast cancer. These outcomes included wound complication, infection, hematoma, seroma, breast pain, fat necrosis, radiation pneumonitis, rib fracture, graft or implant complications, implant removal and other post-operative complications.
To assess cost we looked at all claims that occurred between diagnosis and 24 months after diagnosis to assess total cost and costs were adjusted for medical inflation and are reported in 2014 dollars. We also identified complication related cost which we defined as the sum of all costs that occurred on days when a complication was noted in the insurance claims. We also defined non-complication costs as the difference between total cost and complication cost. You can think of non-complication cost as essentially reflecting the baseline cost of these different treatments if no complications were to occur.
So what did we find? In the MarketScan cohort, which was about 44,000 patients, the median age was 53 and the most common treatment was lumpectomy plus whole breast irradiation with 38% of patients. Mastectomy alone and mastectomy plus reconstruction were the next most common, each representing approximately one quarter of treated patients. In the SEER Medicare cohort, which had approximately 60,000 patients, the most common treatment was also lumpectomy plus whole breast irradiation, nearly 50% of patients, with the next most common treatment being mastectomy alone and, of note, relatively few patients in the older SEER Medicare cohort were treated with mastectomy plus reconstruction.
When evaluating the outcome of any complication, the treatment group associated with the highest risk of complication was mastectomy plus reconstruction at 56% whereas the treatment associated with the lowest risk of complication was mastectomy alone at 25%. In the SEER Medicare cohort similarly mastectomy plus reconstruction was associated with the highest risk of any complication. In this cohort all complication risks were somewhat higher and mastectomy plus reconstruction the risk was 69%. In contrast, the treatment associated with the lowest risk of any complication was lumpectomy alone.
We created logistic regression models for the outcome of any complication, adjusting for age, race, comorbidity, chemotherapy receipt, axillary surgery and nodal positivity. These are two separate models in two separate cohorts and notably we found very similar findings. So, relative to lumpectomy plus whole breast irradiation, treatment with mastectomy plus reconstruction was associated with a nearly twofold increased risk in the outcome of any complication. Of note, lumpectomy plus brachytherapy was also associated with a modest increased risk in any complication ranging from 36-46% increase in risk. When we evaluated total cost, remember this is any cost occurring within two years of diagnosis, in the MarketScan cohort we found that mastectomy plus reconstruction was the most expensive treatment and mastectomy alone was the least expensive treatment. Relative to the most common treatment, lumpectomy plus whole breast irradiation, mastectomy plus reconstruction was $23,000 more expensive per patient. In the SEER Medicare cohort the most expensive treatment was lumpectomy plus brachytherapy and the least expensive treatment was lumpectomy alone. Again, looking at the difference between lumpectomy plus whole breast and mastectomy plus reconstruction, mastectomy plus reconstruction was associated with approximately a $2,000 increase in cost per patient.
When evaluating simply complication costs, to me one of the most surprising findings of the study was that the average patient treated with mastectomy and reconstruction who has private insurance results in a complication cost of $10,000 per patient. This is approximately $9,000 higher than the cost of complications with lumpectomy plus whole breast irradiation. Similarly in the SEER Medicare cohort mastectomy plus reconstruction was also an outlier with approximately $2,500 increased cost per patient compared to lumpectomy plus whole breast irradiation.
When evaluating non-complication costs, which could be thought of as treatment costs in the absence of complications, again mastectomy plus reconstruction was the most expensive treatment in the MarketScan cohort and approximately $15,000 more expensive than lumpectomy plus whole breast irradiation. In contrast, in the SEER Medicare cohort mastectomy plus reconstruction was slightly less expensive than lumpectomy plus whole breast irradiation, about $700 in the black, as I have shown here. So this indicates that mastectomy plus reconstruction is not terribly more expensive if you can avoid complications in older patients who are Medicare beneficiaries.
This study has some important limitations. First of all, not all patients included in these cohorts would have been eligible for all the different treatments so our findings represent what the average patient treated with these treatments can expect in the community setting. Also, I would be the first to acknowledge that assessing complications via claims codes is imperfect and doesn’t necessarily reflect the severity of these complications.
There’s a very important caveat which I think needs to be clear when interpreting these findings and that is that these findings are most relevant to patients and payers when contemplating initial management and both lumpectomy and mastectomy are viable treatment options for a patient. However, if a mastectomy has been performed, reconstruction is generally considered to be a high value intervention and it would be inappropriate to conclude otherwise from the data that we have presented.
So, in conclusion, there’s a twofold increase in complications with mastectomy and reconstruction compared to lumpectomy plus whole breast irradiation resulting in excess cost. The complication burden is modestly elevated with brachytherapy but cost of complications is minimally higher than lumpectomy plus whole breast. Complication burden and total cost are lowest with mastectomy alone for younger women and lumpectomy alone for older women. For women who wish to preserve a breast mound, lumpectomy plus whole breast irradiation appears to be a high value treatment for younger women and either lumpectomy alone or lumpectomy plus whole breast appear to be high value treatments for older women. I would add that the value of lumpectomy plus whole breast irradiation could be further improved if radiation oncologists adopt shorter, more cost effective schedules for delivering whole breast irradiation. Thank you.