Pancreatic Acinar Cell Carcinoma

Metastatic pancreatic acinar cell carcinoma with BRCA2 gene alternation resected after modified FORFIRINOX therapy: a case report and literature review

Background

Pancreatic acinar cell carcinoma (PACC) is a rare subtype of pancreatic cancer, and its clinicopathological behavior is not fully understood because of its rarity. The excision of the tumor is the best treatment, but PACC patients often have distant metastasis at the time of first diagnosis and sometimes have relapse after surgery. Thus, appropriate anti-tumor agents need to be administered; however, there is still no standard chemotherapy regimen for PACC. We report a case of PACC in a patient with breast cancer susceptibility gene (BRCA)2 gene alternation whose hepatic metastasis was shrunk by a treatment with a modified FORFIRINOX (mFFX) regimen. The patient also underwent conversion surgery after the mFFX treatment.

Case Description

A 67-year-old man was treated for breast cancer in 2016. In 2022, he experienced a continuous left back pain, and abdominal computed tomography (CT) revealed a 47-mm hypo-dense mass in the pancreatic tail and a 100-mm slightly enhanced mass in the liver at segment 8. He was diagnosed with PACC with liver metastasis by liver and pancreatic tumor biopsies. He was started on mFFX and, at the same time, we performed an analysis of the BRCA gene alternation with blood and genetic screening using a liver biopsy specimen. Later, the germline BRCA2 gene alternation was identified, and mFFX was continued. He had considerable tumor shrinkage after 13 mFFX cycles and was then sent for surgery. An excised sample showed no tumor in the liver and a 900-µm residual tumor in the pancreatic tail. He had relapse in the liver at segment 6 at 12 months after surgery, which was then excised. He had a lymph node relapse at 3 months after the second surgery, and was receiving olaparib.

Conclusions

mFFX might be prioritized as the first-line chemotherapy for PACC patients, and an analysis of the BRCA gene alternation needs to be conducted.

Pathological complete response with FOLFIRINOX therapy for recurrence of pancreatic acinar cell carcinoma

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.

New treatment insights into pancreatic acinar cell carcinoma: case report and literature review

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.

Germline BRCA2 variants in advanced pancreatic acinar cell carcinoma: A case report and review of literature

BACKGROUND

Pancreatic acinar cell carcinoma (PACC) is a rare tumor. Up to 45% of PACCs have alterations in the DNA damage repair pathway and 23% harbor rearrangements in the BRAF or RAF1 genes. We present a PACC case with a germline BRCA2 likely pathogenic variant (LPV) to highlight the impact of genomic testing on treatment decisions and patient outcomes. In our larger case series, we provide clinic-based information on additional 10 PACC patients treated in our center.

CASE SUMMARY

A 70-year-old male was diagnosed with advanced PACC. At presentation, he was cachectic with severe arthralgia despite prednisolone and a skin rash that was later confirmed to be panniculitis. He was treated with modified FOLFIRINOX (mFFX) with the knowledge of the germline BRCA2 LPV. Following 11 cycles of mFFX, a computed tomography (CT) scan demonstrated significant tumor response in the pancreatic primary and hepatic metastases, totaling 70% from baseline as per Response Evaluation Criteria in Solid Tumors. Resolution of the skin panniculitis was also noted. We identified two additional PACCs with druggable targets in our case series. Our data contribute to practical evidence for the value of germline and somatic profiling in the management of rare diseases like PACC.

CONCLUSION

This patient and others in our larger case series highlight the importance of genomic testing in PACC with potential utility in personalized treatment.

Pancreatic acinar cell carcinoma: A comprehensive review

Acinar cell carcinoma (ACC) is a rare pancreatic malignancy with distinctive clinical, molecular, and morphological features. The long-term survival of ACC patients is substantially superior to that of pancreatic adenocarcinoma patients. As there are no significant patient series about ACCs, our understanding of this illness is mainly based on case reports and limited patient series. Surgical resection is the treatment of choice for patients with the disease restricted to one organ; however, with recent breakthroughs in precision medicine, medicines targeting the one-of-a-kind molecular profile of ACC are on the horizon. There are no standard treatment protocols available for people in which a total surgical resection to cure the condition is not possible. As a result of shared genetic alterations, ACCs are chemosensitive to agents with activity against pancreatic adenocarcinomas and colorectal carcinomas. The role of neoadjuvant or adjuvant chemoradiotherapy has not been established. This article aims to do a comprehensive literature study and present the most recent information on acinar cell cancer.

Multicenter Retrospective Analysis of Chemotherapy for Advanced Pancreatic Acinar Cell Carcinoma: Potential Efficacy of Platinum- and Irinotecan-Containing Regimens

OBJECTIVES

The aim of this multicenter retrospective study was to identify the optimal chemotherapeutic regimen for advanced pancreatic acinar cell carcinoma (PACC).

METHODS

Fifty-eight patients with histopathologically confirmed advanced PACC who had received chemotherapy between 1996 and 2013 were enrolled. The clinical characteristics of the patients and the treatment efficacy data were collected from the medical records at 16 Japanese institutions, using standardized data collection instrument.

RESULTS

The most commonly selected treatment regimens were gemcitabine-, fluoropyrimidine-, platinum-, and irinotecan-containing regimens. The overall response rate in the patients who received first-line chemotherapy were 7% and 38%, respectively, and the median overall survival was 13.2 months. When the data for all the treatment lines were aggregated, the response rates to gemcitabine-, fluoropyrimidine-, platinum-, and irinotecan-containing regimens were 7%, 18%, 40%, and 29%, respectively. The overall survival tended to be better in patients who had received a platinum-containing regimen (hazard ratio, 0.50; 95% confidence interval, 0.23-1.11; P = 0.08) or irinotecan-containing regimen (hazard ratio, 0.42; 95% confidence interval, 0.15-1.19; P = 0.09) at least once in the treatment course as compared with those who had not.

CONCLUSIONS

Our findings suggested that platinum- and irinotecan-containing regimens exhibited some potential efficacy in patients with advanced PACC.

The cytologic and immunohistochemical findings of pancreatic mixed acinar-endocrine carcinoma

BACKGROUND

The classification of epithelioid pancreatic neoplasms based on fine-needle aspiration (FNA) is important for proper management, as distinction of pancreatic neuroendocrine neoplasms from other similar appearing lesions can result in significantly different treatment. Mixed acinar-endocrine carcinomas (MAEC) are genetically related to acinar carcinomas and are treated as such. We reviewed cases of MAEC to better characterize their cytologic and immunohistochemical features.

METHODS

Eight FNAs of MAECs were identified and reviewed. A chart review for each case was conducted.

RESULTS

All patients were male, 42-68 years of age, and presented with either Stage 3 or 4 disease. Smear backgrounds of all cases showed naked nuclei without significant necrosis. The smears were cellular with cells arranged in either three-dimensional (3D) clusters with intervening capillaries or singly dispersed. Acinar formation was a prominent feature. Cells were round to oval with small to moderate amounts of delicate cytoplasm. The nuclei were round to oval with mild to moderate anisonucleosis with granular chromatin and small nucleoli. Apoptotic bodies and mitoses were noted in most cases, with Ki67 indices of 10%-48%. All tumors, by definition, demonstrated expression of trypsin and synaptophysin with variable chromogranin expression (50%).

CONCLUSION

The cytology of acinar cell carcinoma shares features with aspirates of other nonductal adenocarcinoma neoplasms of the pancreas. A clue to the diagnosis is that tumors show high Ki67 indices and a diagnosis of MAEC should be excluded anytime a diagnosis of Grade 2 or 3 well-differentiated neuroendocrine tumor or high-grade neuroendocrine carcinoma is in the differential.

Long-term survival of two patients with recurrent pancreatic acinar cell carcinoma treated with radiofrequency ablation: A case report

BACKGROUND

Pancreatic acinar cell carcinoma (PACC) is a rare type of malignant pancreatic cancer that represents approximately 1% of all pancreatic neoplasms. Due to its very low incidence, only a few retrospective studies are available. Although surgery is the first choice for treatment, most patients experience recurrence (mainly in the liver) and there are no clear recommendations for patients with advanced disease.

CASE SUMMARY

We report two patients with PACC treated with surgery who experienced tumour recurrence in the liver. Patient 1 carried a germline mutation in the APC gene. Both patients were treated with gemcitabine plus oxaliplatin and gemcitabine plus capecitabine as first- and second-line therapies, respectively. After a favourable response to chemotherapy, the patients underwent radiofrequency ablation of the remaining liver metastases. For patient 1, we documented a relapse in the liver after a disease-free period of 9 mo, and treatment with gemcitabine plus capecitabine was restarted. The patient achieved a complete response, and he remains alive without evidence of disease recurrence after six years. After radiofrequency ablation, patient 2 experienced disease-free survival for 21 mo, when peritoneal relapse was diagnosed and treated with chemotherapy. The patient achieved a stable disease state for nearly two years; nevertheless, further progressive disease was documented, and he died seven years after the first relapse.

CONCLUSION

PACC presents different biological behaviours than pancreatic adenocarcinoma. Multidisciplinary treatment involving local ablative therapies may be considered for PACC.

Pancreatic acinar cell carcinoma--literature review and case report of a 56-year-old man presenting with abdominal pain

We present a case of acinar cell carcinoma of the pancreas (ACC) with metastasis to the liver in a patient who presented with complaints abdominal pain. The presentation, diagnosis, and management of a 56-year-old man with ACC are discussed here. Imaging with computerized tomography (CT) in particular is crucial in the diagnosis, which can identify the primary lesion as well as metastases. ACC should be considered in the differential as a source of abdominal, epigastric, or back pain with imaging that is suggestive of the diagnosis as prompt recognition and initiation of treatment is paramount in the overall prognosis.