Excellent long term oncological outcome in a patient with rare glycogen rich clear cell carcinoma of breast following breast conservation surgery

INTRODUCTION: We present a case report of excellent oncological outcome after 7-year follow up in a female Indian patient with pT2N3aM0 rare GRCC of the breast following breast conservation surgery and appropriate adjuvant treatment. Glycogen rich cell carcinoma (GRCC) is a rare subtype of primary malignant neoplasm of the breast which is not commonly discussed. Only approximately 288 cases have been reported since its first description globally with reports of varying prognosis. Even less (4 patients), which have been reported from India have described only clinic pathological features. This is first case report of patient from India discussing long term oncological outcome of a patient with rare GRCC (pT2N3aMO) of the breast following breast conservation surgery and appropriate adjuvant treatment. A 41-year-old lady presented to us with history of 2 × 2 cm right breast lump for 2 weeks. A BIRAD IV hypo echoic lesion with slightly irregular margins in the upper outer quadrant of the right breast and right axillary lymphadenopathy was reported in mammogram. PET CT showed metabolically active lesion 2.3 × 1.3 cm enhancing nodule with spiculated margins at the same site (SUV-10.8) with metabolically active right axillary metastatic lymphadenopathy (SUV-11) with no distant metastases. Core biopsy indicated Ductal carcinoma. Patient underwent right breast conservation surgery (Wide local excision and oncoplasty with axillary clearance) uneventfully followed by appropriate adjuvant treatment (Chemotherapy, Targeted treatment, Radiotherapy). The final pathological stage was Glycogen rich clear cell carcinoma, pT2N3a M0 with Her2 positive but negative for ER and PR with Ki 67–50 %. The patient had excellent outcome and was alive and cancer free even after 7 years follow up. CONCLUSION: The purpose of reporting this case is to increase the knowledge about this rare subtype of breast cancer which underwent organ preservation. This case report reveals that clinical behavior and oncological outcome of GRCC breast can be unexpected, unusual, varied and even good, contrary to recent 2019 SEER data (Zhou Z, Kinslow CJ, Hibshoosh H, et al. Clinical features, survival and prognostic factors of glycogen-rich clear cell carcinoma (GRCC) of the breast in the US population. J Clin Med. 2019; 8: pii: E246).