Developing a secondary malignancy—a new, distinct cancer unrelated to the first—is a recognized concern for breast cancer survivors. Lymphoma, a cancer of the immune system’s lymphocytes, is one such secondary cancer that can occur after breast cancer treatment. While the overall risk is low, two specific scenarios link a history of breast cancer or its reconstruction to an elevated risk of developing lymphoma. Understanding these associations and recognizing the signs is an important aspect of long-term survivorship care.
The General Risk of Secondary Cancers
A second primary malignancy is a new cancer that develops in a patient successfully treated for a previous, unrelated cancer, distinct from a recurrence. The increased risk for cancer survivors compared to the general population is often related to the initial treatment modalities used to eradicate the first tumor.
Systemic treatments like chemotherapy, particularly regimens that include alkylating agents, can increase the risk of secondary cancers by causing DNA damage in healthy cells. This damage can lead to the development of blood-related malignancies, such as leukemia. Radiation therapy also causes damage to the DNA of nearby healthy tissue within the treatment field, creating a slight, long-term risk for new cancers.
Some patients may also have shared biological or genetic predispositions that increase the likelihood of developing multiple cancers. For instance, a mutation in the BRCA1 or BRCA2 genes elevates the risk for breast cancer and other cancers, such as ovarian cancer. However, for most survivors, secondary cancer development is linked to the long-term biological effects of the powerful therapies necessary to treat the initial breast cancer.
Specific Lymphoma Types Linked to Breast Cancer Treatment
One of the most specific associations between breast cancer treatment and lymphoma involves the use of certain breast implants for reconstruction after mastectomy. This is known as Breast Implant-Associated Anaplastic Large Cell Lymphoma (BIA-ALCL), a rare type of T-cell Non-Hodgkin Lymphoma. BIA-ALCL is primarily linked to implants with a textured surface, rather than smooth implants, and is considered a localized malignancy of the immune system.
The proposed mechanism for BIA-ALCL development centers on a chronic inflammatory response triggered by the textured surface of the implant. This texture can harbor bacterial biofilms, leading to persistent, low-grade inflammation within the fibrous capsule that forms around the implant. Over many years, this chronic stimulation of T-cells may lead to a malignant transformation, resulting in the lymphoma. This cancer typically develops in the fluid, called a seroma, that accumulates between the implant and the surrounding scar capsule.
A separate risk is the development of a radiation-associated lymphoma, typically a Non-Hodgkin Lymphoma, in the area exposed to radiation therapy. Standard breast cancer radiation is highly targeted, but the cumulative effect of radiation exposure can lead to the infrequent development of various malignancies, including lymphomas, within the chest wall or armpit region. This risk is generally considered to have a long latency period, often appearing many years after the initial treatment.
Recognizing Symptoms and Diagnostic Procedures
Recognizing the symptoms of a secondary lymphoma is important for breast cancer survivors. General symptoms of lymphoma, often referred to as “B symptoms,” include unexplained, persistent fevers, drenching night sweats, and unintentional weight loss. Patients may also notice new, persistent, and painless swelling of lymph nodes in the neck, armpit, or groin area.
For BIA-ALCL, the most common presentation is a late-onset swelling or enlargement of the breast, typically occurring several years after the implant was placed. This is usually due to the rapid accumulation of fluid, or a seroma, around the breast implant. Less commonly, it may present as a palpable mass near the implant or capsule.
The diagnostic pathway begins with a thorough physical examination and advanced imaging, such as a PET or CT scan, to identify any enlarged lymph nodes or masses. If BIA-ALCL is suspected due to late-onset seroma, the distinct diagnostic procedure involves aspirating the fluid surrounding the implant. This fluid is then analyzed for malignant cells and specifically tested for the CD30 marker, which is characteristic of BIA-ALCL. Ultimately, a tissue biopsy is required for a definitive diagnosis of any secondary lymphoma.
Treatment Strategies for Secondary Lymphoma
Treatment for a secondary lymphoma is highly individualized, taking into account the patient’s prior history of breast cancer and the treatments they have already received. For most types of secondary lymphoma, standard modalities include systemic approaches such as chemotherapy and immunotherapy. Radiation therapy may also be utilized, though its use is carefully considered if the area was previously treated for breast cancer.
The treatment for BIA-ALCL is unique and often involves a surgical approach. If the disease is confined to the fluid and the capsule, the recommended treatment is the complete surgical removal of both the implant and the surrounding fibrous capsule, known as an en bloc capsulectomy. This surgical removal is frequently curative and results in a favorable prognosis. For more advanced cases that have spread beyond the capsule, chemotherapy or radiation may be added to the treatment plan.