[Two Cases of Catheter-Related Venous Thrombosis Treated with Direct Oral Anticoagulants(DOAC)].

The implantation of a totally implantable central venous(CV)access port is considered a risk factor for venous thromboembolism( VTE). In the treatment of catheter-related thrombosis(CRT), both European and American guidelines recommend anticoagulation therapy with catheters in place. We experienced 2 cases of upper extremity deep vein thrombosis (UEDVT)after the implantation of CV access ports through the left subclavian vein for adjuvant chemotherapy in patients with resected breast cancer. Both patients were successfully treated with direct oral anticoagulants(DOAC) while the port remained in place with a careful follow-up that included monitoring of serum D-dimer levels. The administration of DOAC to CRT that develops in patients undergoing postoperative adjuvant chemotherapy for breast cancer may be relatively safe, with a low potential for adverse events such as bleeding.

[A Case of Pathological Complete Response Following Neoadjuvant S-1 Monotherapy in an Elderly Patient with Locally Advanced Breast Cancer].

An 86-year-old woman was referred to our hospital after an incidental CT scan of the trunk revealed a mass in the left breast and enlarged axillary lymph nodes. A core needle biopsy(CNB)from a 2 cm mass in the left breast revealed invasive ductal carcinoma, weakly positive result for ER, negative result for PgR, and negative result for HER2. She also had multiple enlarged left supraclavicular lymph nodes and was T2N3cM0, Stage ⅢC on pretreatment evaluation. She was given the S-1 oral drug of choice, starting with 80 mg/day/4-week dosing with a 2-week rest. Eight months after the start of S-1, a partial mastectomy and sentinel lymph node biopsy were performed. Pathological findings showed a pathological complete response(ypTis/ypN0)with only a 2 mm non-invasive carcinoma remnant in the left mammary gland. S-1 is weakly recommended as primary chemotherapy for HER2-negative metastatic recurrent breast cancer, but there are no reports to date of complete response in resection cases. S-1 may be administered to patients with locally advanced breast cancer who cannot tolerate standard drug therapy and may be converted to resection after a successful response.

[A case of metastatic colorectal cancer with icterus due to multiple liver metastases treated effectively by FOLFOX plus bevacizumab].

A 64-year-old male with fatigue and icterus was referred to our hospital. Computed tomography(CT)demonstrated multiple liver metastases and colonoscopic examination revealed advanced rectal cancer, which was diagnosed as moderately- differentiated adenocarcinoma without KRAS mutation. His serum total bilirubin level was 15.6 mg/dL. We started combination chemotherapy with 5-fluorouracil, Leucovorin and oxaliplatin(modified FOLFOX6)at a 20% lower than standard dosage for safety. When his bilirubin fell to 2.3 mg/dL after 4 courses of mFOLFOX6, the doses of 5-fluorouracil and oxaliplatin were increased to standard doses, and treatment with bevacizumab of 5 mg/kg every 2 weeks was begun. After another 3 courses of chemotherapy, his bilirubin was normalized to 0.8 mg/dL. No significant toxicity was observed. Combination chemotherapy with mFOLFOX6 plus bevacizumab was effective and feasible in this case of metastatic rectal cancer with icterus due to diffuse liver metastases.