[Chemotherapy-Resistant Breast Cancer and Carcinomatous Pleuritis Successfully Treated with Abemaciclib plus Letrozole Therapy].

A 78-year-old woman was examined in the outpatient department with a chief complaint of swelling of the left breast. Examination confirmed a 10 cm mass in the left breast as along with edema and redness of the skin, following which a diagnosis of invasive micropapillary carcinoma was made after biopsy. The CT imaging showed left chest wall invasion, multiple axillary lymph node metastases, and left carcinomatous pleuritis. Since this a case of advanced breast cancer, we initiated treatment with bevacizumab plus paclitaxel. After 8 months, her medication was changed to eribulin, owing to progression of the cancer, which continued even up to 4 months. We then initiated abemaciclib plus letrozole therapy as the third treatment. We observed tumor reduction and clearing of pleural effusion with no serious adverse events, and continued her therapy for 11 months before the cancer progressed. We report a case of chemotherapy-resistant breast cancer and carcinomatous pleuritis in an older adult patient for which abemaciclib plus letrozole therapy was effective.

[A Case of Lung Metastasis of the Breast Cancer with a Remarkable Response to Stereotactic Body Radiation Therapy(SBRT)].

A 69-year-old woman admitted to our hospital with the lump in the left breast. Further examination was performed for the lesion, and it was diagnosed as invasive ductal carcinoma. Partial resection and sentinel lymph node biopsy were performed. Pathological diagnosis was metaplastic carcinoma with squamous metaplasia. As the adjuvant treatment, docetaxel and cyclophosphamide(TC)therapy and radiotherapy was performed. Following the treatment of those, tegafur-uracil was administered for 2 years. Three years after the surgery, an isolated lung metastasis was revealed by CT. Capecitabine and cyclophosphamide(XC)therapy was administered, but not effective. Stereotactic body radiation therapy(SBRT)was performed for the lesion. As a result, the metastatic lesion was obscured. Drug therapy was stopped due to adverse events, and she is observed by no medication. Thirty-six months after SBRT and 78 months after the surgery, the patient is alive without recurrence. SBRT could be an effective treatment strategy for the oligometastais of the lung.

[A case of mucinous carcinoma treated by local excision after long-term serial observations].

We report a case of a 45-year-old woman in whom an abnormality was identified by an examination when she was 42 years old. Breast ultrasonography revealed a cyst in the C area of the left breast. Ultrasonography performed 3 years later showed a mass lesion, 1 cm in diameter, in the C area of the left breast. Contrast-enhanced magnetic resonance imaging (MRI) showed a mass shadow. Core needle biopsy was performed, and the pathological diagnosis was mucinous carcinoma. Partial excision of the breast and sentinel lymph node biopsy were performed. The final histopathological diagnosis was mucinous carcinoma( pure type, estrogen receptor[ ER][ +], progesterone receptor[ PgR][ +], human epidermal growth factor receptor-2[ HER2][ 0], Ki67[ 10%], T1N0M0, stage I). One year after the operation, no signs of recurrence or metastasis have been observed. It was difficult to ascertain the presence of a lesion as the patient experienced pregnancy and childbirth during serial observations. An early diagnosis was made by imaging techniques such as consecutive ultrasonography, owing to which we were able to treat the patient early. The findings of this case emphasize the need for serial imaging studies.

Successful Retreatment of Metastatic Triple-negative Breast Cancer With Immune Checkpoint Inhibitors and Chemotherapy.

BACKGROUND/AIM: The efficacy of retreatment with immune checkpoint inhibitors (ICIs) in programmed death-ligand 1 (PD-L1) positive metastatic or recurrent triple-negative breast cancer (mTNBC) remains unknown. We report a case of a patient with recurrent triple-negative breast cancer who was successfully treated with two different ICIs in combination with chemotherapy. CASE REPORT: A 60-year-old female patient was treated with neoadjuvant chemotherapy consisting of epirubicin + cyclophosphamide (EC) followed by docetaxel (DTX). The tumor shrank with EC, but progressed with DTX. One year after the surgery, the patient presented with multiple lung metastases. The patient received combination therapy with atezolizumab and nab-paclitaxel and achieved a partial response (PR). However, the disease progressed after 6 months. She received eribulin as second-line chemotherapy for 4.5 months, and her treatment was changed to pembrolizumab, carboplatin, and gemcitabine as third-line chemotherapy. The tumor immediately reduced and disappeared after three cycles of this treatment and achieved PR. CONCLUSION: This case illustrated that retreatment with ICIs was effective.