Diagnosis of a Malignant Intramammary Node Retrospectively Aided by Mastectomy Specimen MRI-Is the Search Worth It? A Case Report and Review of Current Literature
A 61-year-old female was presented to the breast clinic with complaints of a lump in the right breast since the past 3 months. On examination, a lump was palpated in the right upper-outer quadrant without any palpable axillary nodes. The contralateral breast and axilla were clear. Mammography showed a high density lesion in the upper outer quadrant of the right breast with perilesional architectural distortion and spiculations (). The MRI showed a soft tissue mass showing irregular spiculated margins in the upper outer quadrant of the right breast which was hypointense on T1W images and hyperintense on Short Tau (t) (inversion time) Inversion Recovery (STIR) images; further, it showed areas of restricted diffusion at the periphery. Another similar appearing nodular lesion was noted at the right 12 o'clock position measuring approximately 5 mm (). It showed a homogeneous contrast enhancement with rapid increase in signal intensity on the postcontrast scan, followed by a washout-type II signal intensity curve favoring a malignant lesion. A second-look ultrasound examination was performed, presenting a tiny hypoechoic nodule (). With the lesion being small, an ultrasound-guided FNAC was attempted in the same sitting, which was negative for malignancy. The lesion was classified as indeterminate and the patient underwent modified right radical mastectomy with axillary node sampling. Sentinel lymph node biopsy and lymphoscintigraphy are not routinely performed at out institution. The final histopathology was reported as infiltrating ductal carcinoma; grade II without nodal involvement as the axillary nodes were negative. The smaller lesion was not evaluated in pathological grossing owing to its size. As the lesion was highly suspicious for malignancy, the resected pathology specimen was subjected to an MRI examination .The specimen MRI confirmed the STIR hyperintense lesion observed previously (). The lesion was then localized under MR guidance and methylene blue was injected at the site (). The specimen was sent back for regrossing and pathology examination. Additional sections were taken from the marked region, which showed intramammary node with metastasis from ductal carcinoma without perinodal extension (). Thus, the disease was then labeled as follows: carcinoma with axillary node-negative but metastatic intramammary node, which upgraded the disease to stage II. The patient was placed on adjuvant systemic therapy and close follow-up, as the presence of intramammary node correlates with poorer overall prognosis.