A resected case of acinar cell carcinoma of the pancreas with liver metastasis following chemotherapy using modified FOLFIRINOX.

BACKGROUND: Acinar cell carcinoma of the pancreas is a rare exocrine malignancy representing less than 1% of all pancreatic neoplasms. It has been reported that it responds to treatment differently from pancreatic ductal adenocarcinoma and the treatment algorithm for acinar cell carcinoma usually depends on the stage of the respective tumor and the patient's current status. CASE PRESENTATION: A 60-year-old man presented with upper abdominal pain and anorexia. Abdominal ultrasonography showed a large-sized hepatic mass and he was referred to our hospital. Contrast-enhanced computed tomography demonstrated a 110-mm low-density area occupying the right hemi-liver and an enhanced mass of 70 × 56 mm in the tail of the pancreas, which seemed to directly infiltrate into the spleen. The case was diagnosed as acinar cell carcinoma with a simultaneous liver metastasis identified by liver biopsy. Upfront resection of pancreatic cancer with distant metastasis might not be considered as an optimal choice, and in this case chemotherapy was administered prior to curative resection. Chemotherapy using the modified FOLFIRINOX regimen was undertaken, resulting in a partial remission; the liver tumor reduced in size from 110 to 47 mm and the pancreatic tumor from 70 to 40 mm. The patient then safely underwent curative hepatic resection with distal pancreato-splenectomy. Histological examinations revealed small-sized atypical cells with large nuclei that had formed acinar patterns, and immunostaining with trypsin was positive in tumor cells, which was in accordance with acinar cell carcinoma. More than 3 years later, the patient is doing well without any recurrence. CONCLUSION: Aggressive and curative surgery in combination with chemotherapy such as FOLFIRINOX could be a treatment option to achieve long-term survival in cases of acinar cell carcinoma with liver metastases.

Characteristics of a real-time radiation exposure dosimetry system using a synthetic ruby for radiotherapy.

Radiotherapy-related medical accidents are frequently caused by planning problems, excessive irradiation during radiotherapy, or patient movement. This is partly because the local exposure dose cannot be directly monitored during radiotherapy. This article discusses the development of our recent real-time radiation exposure dosimetry system that uses a synthetic ruby for radiation therapy. Background noise was observed before the measurement of the short-term characteristic features. Regarding the relationship between the number of photons and dose rate, using 100 monitor units (MU)/min as the measurement value, the counts decreased by approximately 10% at 600 MU/min. A clear correlation was observed between the MU value and the number of photons (R2 = 0.9987). The coefficient of variation (%CV) was less than ± 1.0% under all the irradiation conditions. Slight differences were observed between the ion chamber and the synthetic ruby dosimeters in the measurement of the percentage depth dose. However, this difference was almost matched by correcting for the Cherenkov light. Although some problems were observed with the synthetic ruby dosimeter system, our results indicate that the developed dosimeter can be used to measure the irradiation dose of patients in real time, with no significant impact on the data, as any effect would be masked by the larger effect of the ruby; however, the impact requires a detailed assessment in the future.

[A Case of Long-Term Clinical Complete Response after Chemotherapy for Locally Advanced Rectal Cancer].

With the advancement ofchemotherapy against colorectal cancer, clinical complete responses(cCR)are more frequently observed. We report a case oflocally advanced rectal cancer with maintained long-term cCR after chemotherapy alone. Detailed examinations ofa man in his 60s revealed that he had poorly controlled diabetes mellitus, with elevated serum CEA and CA19-9 levels. Colonoscopy revealed rectal cancer(Rba). Besides the prostate invasion observed in the CT scan, intestinal obstruction was caused by a tumor that required surgical removal. However, the tumor was unresectable due to prostate and pelvic wall metastases; therefore, only sigmoid colostomy was performed. After 6 courses of mFOLFOX6, the tumor shrunk, and prostate invasion reduced as confirmed by the CT scan. Chemotherapy was switched to sLV/5FU2 due to the occurrence of peripheral neuropathy. No tumor was found after 20 courses of treatment, and cCR was achieved after 58 courses ofcontinuous and consecutive treatment. Throughout the treatment, radical resection was proposed to the patient; however, the surgery was not performed because of his lifestyle, ie, heavy smoking, which resulted in poor blood sugar control. The patient appears to be tumor free for 7 years after the initiation of chemotherapy.