BACKGROUND: Pancreatic acinar cell carcinoma (PACC) is a rare pancreatic neoplasm. Recently, molecular analysis revealed that PACC shows a high frequency of the BRCA1/2 mutation and is likely to be considered a cancer associated with hereditary breast and ovarian cancer (HBOC). Hereditary cancers, including HBOC, are characterized by multifocal and/or metachronous tumors. However, no case reports exist of germline BRCA1-mutated synchronous and metachronous PACC.
METHODS: A 58-year-old man was diagnosed with synchronous and metachronous PACC at the age of 56 and underwent two surgeries. Ten months after the second surgery, the patient developed multiple liver metastases. Gemcitabine plus nab-paclitaxel therapy was administered as first-line chemotherapy. After seven cycles, computed tomography examination revealed progressive disease (PD). Therefore, modified FOLFIRINOX (mFFX) was administered as second- line chemotherapy. After 19 cycles of mFFX, comprehensive cancer genomic profiling (CGP) identified a BRCA1 pathogenic variant that was confirmed to be germline origin. Accordingly, we treated the patient with olaparib; however, he was diagnosed with PD after 4 months. He subsequently died 5 years and 9 months after the initial surgery, and 3 years and 10 months after chemotherapy. Based on the genetic data of the patients, his family members received genetic counseling followed by cascade testing. Consequently, the same gBRCA1 pathogenic variant was detected in the son and his surveillance for HBOC-related cancers was initiated.
CONCLUSIONS: We diagnosed a 58-year-old man with a synchronous and metachronous PACC with germline BRCA1 pathogenic variant. Considering that PACC is likely to have BRCA1/2 mutations responsible for HBOC, we need to be aware of the possible presence of multifocal and/or metachronous tumors in patients with PACC. Additionally, patients with PACC should undergo genetic examinations, which would be beneficial in determining treatment strategies and health care for blood relatives.

Pancreatic acinar cell carcinoma (PACC) is a rare pancreatic tumor type, and ruptured pancreatic tumors are rarer. Computed tomography (CT) in a 48-year-old man incidentally revealed a raptured pancreatic tail tumor. The patient was treated conservatively because he was asymptomatic, and his general condition was stable. After a detailed examination, the pancreatic tumor was diagnosed as raptured PACC. Considering the potential infiltration of tumor cells into the hematoma within the omental sac, our decision is to initiate chemotherapy as the primary course of action. A liquid biopsy was performed, and comprehensive genomic profiling of circulating tumor DNA showed a tumor BRCA2 mutation. Chemotherapy with modified FOLFIRINOX (mFFX) was selected as the first treatment. After seven courses of mFFX, the primary tumor diminished remarkably. At this time, the radical resection was performed via distal pancreatectomy with simultaneous resection of the gastric wall and colon, which had adhered strongly to the tumor. Histopathological examination revealed that the tumor had shrunk to less than 5% of its original size due to chemotherapy (Grade 3 of Evans Classification). Devising treatment strategies for ruptured pancreatic malignant tumors is challenging due to the worsening general condition caused by severe abdominal symptoms and intra-abdominal bleeding. In this context, this case-report documents a rare instance of raptured PACC with a tumor BRCA2 mutation that underwent radical resection following mFFX treatment.

Paediatric pancreatic acinar cell carcinoma (PACC) presents a diagnostic challenge, often confused with pancreatoblastoma (PB) due to its rarity. It is crucial to differentiate between PB and PACC, given their distinct therapeutic strategies and prognoses. Histologically, the absence of squamoid nests and scarcity of tumor mesenchyme support PACC. Conversely, the identification of a BRAF alteration leans towards PACC. Here, we present the case of an 8-year-old girl with a well-defined mass in the pancreas. The tumor exhibited a SEC31A-BRAF fusion gene and amplification of 18p, showcasing unequivocal acinar differentiation and a minor degree of neuroendocrine differentiation. Additionally, the tumor displayed scant fibrous stroma, and an absence of squamoid nests, further supporting PACC. Notably, this is the first reported instance of a solid tumor featuring a SEC31A-BRAF gene fusion. The discovery of this novel fusion gene expands our understanding of BRAF fusion partner profiles, particularly in the context of paediatric PACC.

Pancreatic acinar cell carcinoma (PACC) is a very rare subtype of pancreatic cancer. Due to small number of patients, no standard chemotherapy protocol has been established. We experienced an extremely rare case of PACC with liver metastasis that showed a pathological complete response after modified FOLFIRINOX (mFFX) therapy. A 42-year-old man who underwent distal pancreatectomy for an 80 mm tumor at the pancreatic tail 3 years ago was referred to our hospital in September 2017 for the treatment of a recurrent liver tumor. Percutaneous biopsy revealed an acinar-neuroendocrine carcinoma, similar to the surgical specimen. He received eight cycles of irinotecan plus cisplatin chemotherapy. However, the tumor increased in size, and treatment was switched to mFFX therapy. The tumor in the liver shrank remarkably after nine cycles of mFFX therapy. Conversion surgery was selected, and the patient underwent hepatic left and caudate lobectomy 8 months after administration of mFFX. The resected specimen showed no viable tumor cells, indicating a pathological complete response. The histological diagnosis was reconsidered, and PACC was finally diagnosed via an additional immunohistological review. The patient has remained well with no recurrence for 6 years after surgery. This study is the first to report a case of pathological complete response with mFFX therapy for the recurrence of PACC.

A 73-year-old Japanese man with a history of distal biliary cancer treated by pancreatoduodenectomy developed pancreatic acinar cell carcinoma (PACC) treated by remnant pancreatectomy and adjuvant chemotherapy. Thirteen months after surgery, multiple liver metastases developed and FOLFOX chemotherapy was initiated. Based on the PACC diagnosis and a positive family history for breast and ovarian cancer genetic testing was performed which revealed a pathogenic germline BRCA2 variant (c.8629G > T, p.Glu2877Ter). Olaparib therapy was initiated and the metastases responded well (partial response). PACC is a BRCA2-associated cancer which may respond well to PARP inhibitors.

Pancreatic acinar cell carcinoma (PACC) is a rare pancreatic malignancy with unique clinical, molecular, and morphologic features. The long-term survival of patients with PACC is substantially better than that of patients with ductal adenocarcinoma of the pancreas. Surgical resection is considered the first choice for treatment; however, there is no standard treatment option for patients with inoperable disease. The patient with metastatic PACC reported herein survived for more than 5 years with various treatments including chemotherapy, radiotherapy, antiangiogenic therapy and combined immunotherapy.

UNASSIGNED: Pancreatic acinar cell carcinoma (PACC) is rare, and its appropriate treatment remains unknown. We aim to explore the characteristics and optimal treatment of it.
UNASSIGNED: The data on clinicopathologic characteristics, molecular alteration, treatment, and survival of patients diagnosed with PACC at the Sun Yat-sen University Cancer Center from 2005 to 2020 were collected. The optimal treatment was explored by co-analyzing our results and published literatures.
UNASSIGNED: Twenty-two PACC patients were enrolled. Eight of 17 non-metastatic patients received adjuvant chemotherapy. The patients receiving fluoropyrimidine-based regimen (n = 3) had a better median disease-free survival (mDFS) than those with gemcitabine-based regimen (n = 5) (unreached vs 27 months). Eight metastatic patients received first-line chemotherapy. Four patients received second-line chemotherapy. The objective response rate (ORR) of the fluoropyrimidine-based regimen was 85.7% (6/7), much better than that of the gemcitabine-based regimen (0/5). One patient who had responded to the first-line FOLFIRINOX (5-fluorouracil + oxaliplatin + leucovorin + irinotecan) regimen received olaparib as maintenance treatment for 5 months with good tolerance. Thirty-one published literatures, with a total of 86 cases, were included in the co-analysis. The ORR of the first-line fluoropyrimidine-based regimen (n = 47) was higher than that of gemcitabine-based regimen (n = 39) (59.6% vs 15.3%, P < .001). Eight of 11 patients treated with the FOLFIRINOX regimen achieved partial response (PR).
UNASSIGNED: For patients with metastasis, a fluorouracil-based regimen such as FOLFIRINOX may be preferred, and maintenance treatment of poly ADP-ribose polymerase (PARP) inhibitors after effective platinum-containing treatment for breast cancer susceptibility gene (BRCA) mutation patients must be assessed.

UNASSIGNED: Acinar cell carcinoma (ACC) of the pancreas is a rare pancreatic cancer subtype (incidence, 0.5-2%) with unclear epidemiology and prognosis. Sometimes, repeat resection including total pancreatectomy is required for recurrence. We report a case of ACC recurring in the remnant pancreatic head after distal pancreatectomy that was successfully cured by remnant pancreatic resection following combination therapy with nab-paclitaxel (nab-PTX) and gemcitabine (GEM).
METHODS: A 64-year-old woman was referred for pancreatic tumour treatment. CT revealed a 46-mm tumour in the pancreatic body, and endoscopic ultrasonography-guided fine needle aspiration (EUS-FNA) indicated ACC. Distal pancreatectomy was performed, and the final diagnosis was ACC. CT 18 months later showed a 34-mm tumour in the remnant pancreatic head revealed as ACC by EUS-FNA. Portal vein invasion was apparent, so neoadjuvant chemotherapy with nab-PTX and GEM was administered, and remnant pancreatic resection (total pancreatectomy) was performed. No recurrence or distant metastasis was present more than 6 months later.
UNASSIGNED: Mean survival time for ACC is 18-47 months, and prognosis is good compared with pancreatic ductal adenocarcinoma (PDAC). ACC tends to extend and grow along the main pancreatic duct, which increases the recurrence rate to 50-60%. EUS and EUS-FNA were useful for evaluating tumour extension and diagnosis. Repeat pancreatic resection that included total pancreatectomy was feasible and could be performed safely.
CONCLUSIONS: ACC has a better prognosis than PDAC but with a higher recurrence rate. Aggressive surgical resection that included remnant total pancreatotomy with chemotherapy was useful in treating ACC.

BACKGROUND: Pancreatic acinar cell carcinoma (PACC) is a distinct type of pancreatic cancer with low prevalence. We aimed to analyze prognostic factors and survival outcome for PACC in comparison to pancreatic ductal adenocarcinoma (PDAC), based on data from the German Cancer Registry Group.
METHODS: Patients with PACC and PDAC were extracted from pooled data of the German clinical cancer registries (years 2000 to 2019). The distribution of demographic parameters, tumor stage and therapy modes were compared between PACC and PDAC. The Kaplan-Meier method and Cox regression analysis were used to delineate prognostic factors for PACC. Propensity score matching was used to compare survival between PACC and PDAC.
RESULTS: There were 233 (0.44%) patients with PACC out of 52,518 patients with pancreatic malignancy. Compared to PDAC, patients with PACC were younger (median age 66 versus 70, respectively, p < 0.001) and the percentage of males was higher (66.1% versus 53.3%, respectively, p < 0.001). More patients were resected with PACC than with PDAC (56.2% versus 38.9%, respectively, p < 0.001). The estimated overall median survival in PACC was 22 months (95% confidence interval 15 to 27), compared to 12 months (95% confidence interval 10 to 13) in the matched PDAC cohort (p < 0.001). Surgical resection was the strongest positive prognostic factor for PACC after adjusting for sex, age, and distant metastases (hazard ratio 0.34, 95% confidence interval 0.22 to 0.51, p < 0.001). There was no survival benefit for adjuvant therapy in PACC.
CONCLUSIONS: PACC has overall better prognosis than PDAC. Surgical resection is the best therapeutic strategy for PACC and should be advocated even in advanced tumor stages.

Though outcomes for patients with recurrent/refractory malignant germ cell tumors (mGCTs) are poor, therapies targeting mTOR and EGFR inhibition have shown promise in vitro. We hypothesized that the combination of sirolimus and erlotinib will show activity in patients with recurrent/refractory mGCTs. Patients were enrolled in a prospective phase II clinical trial; central review of existing pathology specimens was performed. Of the five patients evaluated, two had their diagnoses revised to pancreatic acinar cell carcinoma and alpha-fetoprotein (AFP)-secreting gastric adenocarcinoma, respectively. Although mGCTs are common AFP-secreting neoplasms, recurrence or refractoriness to standard regimens should prompt histologic reevaluation for other diagnoses.