1. Occult Breast Cancer: The essential is invisible to the eyes
Farnaz Haji DO, MS, Kiran Chatha MD, Krystina Tongson, DO, Mohammad Masri, MD
Department of Surgery, Larkin Community Hospital, South Miami, FL
INTRODUCTION
IMAGES
DISCUSSION
Occult primary breast cancer is metastatic breast cancer found outside the breast without a detectable primary breast tumor.
The incidence is <1% of all newly diagnosed breast cancers.
Axillary metastasis of this type of breast cancer is very rare and poses a diagnostic and therapeutic challenge to physicians. With new imaging technologies and improvement in radiation and chemotherapy techniques, the detection and management of this rare entity is evolving.
Here we report the case of a 60-year-old female that presented with a painful and erythematous left axillary mass. All breast imaging was negative for a primary breast cancer however lumpectomy of the axillary mass revealed histological findings consistent with breast cancer. Her case and surgical management is discussed, followed by a review of the currently available data on diagnosis, treatment, and prognosis of this rare disease. .
Due to the rarity of occult primary breast cancer, there is still much to be defined about this type of breast cancer. In the presence of an axillary metastasis, preoperative diagnostic workup must first rule out other primary sites of disease.
High sensitivity of MRI for breast tumors may increase diagnostic accuracy and management. However, as depicted in our case, even MRI was not able to detect a primary breast malignancy.
In the absence of a palpable breast mass and normal imaging of both breasts, the origin of axillary mass must be confirmed by pathology and IHC.
If the histological and IHC analysis is compatible with mammary origin, patients are treated according to guidelines for stage II breast cancer.
NCCN recommends that all patients undergo axillary lymph node dissection (ALND). The standard approach is to perform a modified radical mastectomy (MRM) at the time of ALND.
For women who wish to preserve their breast, whole breast radiation therapy is an option. Observation alone is not recommended.
National guidelines provide data for all women with axillary nodal metastases and an occult primary breast cancer to undergo systemic adjuvant therapy according to published guidelines for stage II primary breast cancer.
This case highlights the challenges these cases may present for primary care physicians and in turn affect timely referral to breast surgeons. If not for a thoughtful diagnostic process and careful interdisciplinary approach to patient management decisions, our patient may have received a delayed diagnosis and may not have received definitive treatment.
CASE DESCRIPTION
60-year-old Hispanic female, with a PMHx of hyperlipidemia, DM, and hypothyroidism, presented to a primary care office with a painful and erythematous left axillary mass.
Patient denied familial history of breast, ovarian or uterine cancer. She did not report any discharge from the nipple, breast deformity, trauma to the chest wall or weight loss.
Bilateral screening mammogram showed a left axillary tail nodular lesion classified as BI-RADS 0. Due to the questionable result of the mammogram, the patient pursued a left breast ultrasound, which revealed pathological adenopathy in left breast axillary tail. Biopsy was recommended and the patient underwent lymphadenectomy of the left axillary mass.
Pathological analysis of the mass revealed invasive ductal carcinoma and ductal carcinoma in situ, high grade. Immunohistochemistry (IHC) was ER+, PR- and equivocal for HER2. Her oncotype recurrence score was 55, correlating with an increased rate of 10-year distant recurrence.
Following positive histological results, PET imaging was performed to rule out further distant metastasis. No increased FDG uptake suggesting metastatic disease was reported.
The patient’s work up continued with MRI of the bilateral breasts, which showed no findings of primary breast malignancy. Imaging results confirmed the diagnosis of occult breast malignancy not delineated by breast MRI or mammogram. In the absence of other metastatic disease following removal of the axillary malignancy, the patient was offered close follow up vs. mastectomy.
The patient proceeded with left modified radical mastectomy and was referred to oncology for chemotherapy and possible radiation.
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DCIS- from Axillary biopsy Tumor with necrosis; Levels of Axillary lymph nodes; Axillary mass work up algorithm
Contact information
Farnaz Haji,