En bloc resection of visceral aorta and right kidney due to aortic sarcoma using temporary extracorporeal bypass grafting

DNA Mismatch Repair Deficiency as a Biomarker in Sarcoma

Purpose

Lynch syndrome (LS) is a cancer predisposition syndrome caused by a germline loss-of-function mutation in a mismatch repair (MMR) gene. While sarcomas are not classically considered LS cancers, we investigated the MMR status and clinical features of sarcomas in LS patients to help inform optimal treatment strategies.

Methods

A prospectively maintained institutional clinical cancer genetics database was queried for LS patients (defined by pathogenic germline mutation in a MMR gene) with a documented diagnosis of sarcoma between 1998-2022. Tumor MMR status was determined by immunohistochemistry (IHC) for MMR proteins and secondarily by PCR assay if IHC was normal or intact.

Results

Among the 30 LS patients with sarcoma, germline mutations were most common in MSH2 (50%). The most common sarcoma subtypes were undifferentiated pleomorphic sarcoma (40%) and leiomyosarcoma (27%). Median age at diagnosis was 49.2 years (interquartile range 40.4-62.4). 90% presented with localized disease, and 10% presented with synchronous metastatic disease. Among 10 patients with tissue available for biomarker determination, dMMR was confirmed in 4 (40%), while the remaining (60%) were pMMR. Three patients received immunotherapy. Two of these had confirmed dMMR tumor status: one demonstrated a sustained complete response on pembrolizumab monotherapy for 44 months; the other had a partial response on ipilimumab and nivolumab for 31 months but died from an unrelated cause. In the entire cohort of 30 patients at a median follow-up time of 68.2 months since sarcoma diagnosis (interquartile range 29.0-151.5 months), median overall survival and progression-free survival have not been reached.

Conclusion

While rare, sarcoma can be encountered in patients with LS, particularly those with germline MSH2 mutation. LS-associated sarcomas occur significantly earlier, carry a favorable outcome, and demonstrate the potential for durable response with immunotherapy.

Special features of sarcomas developed in patients with Lynch syndrome: a systematic review

Lynch syndrome (LS) is a genetic predisposition leading to colorectal and non-colorectal tumors such as endometrial, upper urinary tract, small intestine, ovarian, gastric, biliary duct cancers and glioblastoma. Though not classically associated with LS, growing literature suggests that sarcomas might develop in patients with LS. This systematic review of literature identified 44 studies (N=95) of LS patients who developed sarcomas. It seems that most sarcomas developed in patients with a germline mutation of MSH2 (57%) exhibit a dMMR (81%) or MSI (77%) phenotype, as in other LS-tumors. Although undifferentiated pleomorphic sarcoma (UPS), leiomyosarcoma, and liposarcoma remain the most represented histologic subtype, a higher proportion of rhabdomyosarcoma (10%, especially pleomorphic rhabdomyosarcoma) is reported. Further studies are required to better characterize this sub-population.

Case report: Undifferentiated sarcoma with multiple tumors involved in Lynch syndrome: Unexpected favorable outcome to sintilimab combined with chemotherapy

Background

Patients with Lynch syndrome are at an increased risk of developing simultaneous or metachronous tumors, while sarcomas have been occasionally reported. Sarcomas are generally not considered part of the common Lynch syndrome tumor spectrum. However, more and more studies and case reports suggested that sarcoma could be a rare clinical manifestation of Lynch syndrome, leading to new treatment strategies for sarcoma.

Case summary

We report the case of a 74-year-old male patient with Lynch syndrome who had rectal mucinous adenocarcinoma and prostate adenocarcinoma and then developed undifferentiated sarcoma of the left neck two years later. Mismatch repair deficiency (dMMR) was confirmed by immunohistochemical staining for the mismatch repair proteins MSH2, MSH6, MLH1 and PMS2. The result of polymerase chain reaction (PCR) microsatellite instability (MSI) testing of sarcoma showed high-level microsatellite instability (MSI-H). Additionally, a pathogenic germline mutation in MSH2 (c.2459-12A>G) was detected by next-generation sequencing (NGS). Taking into account HE morphology, immunohistochemical phenotype, MSI status, NGS result, medical history and germline MSH2 gene mutation, the pathological diagnosis of left neck biopsy tissue was Lynch syndrome related undifferentiated sarcoma with epithelioid morphology. The patient has been receiving immunotherapy (sintilimab) combined with chemotherapy (tegafur, gimeracil and oteracil potassium capsules) and currently has stable disease. We also reviewed the literature to understand the association between sarcoma and Lynch syndrome.

Conclusion

Sarcoma may now be considered a rare clinical manifestation of Lynch syndrome. Attention and awareness about the association between Lynch syndrome and sarcoma need to be increased. Therefore, timely detection of MMR proteins and validation at the gene level for suspicious patients are the keys to avoiding missed or delayed diagnosis and to identifying patients suited for immunotherapy, which may also help to provide appropriate genetic counseling and follow-up management for patients.

Complete resection and arterial reconstruction for primary sarcoma arising from superior mesenteric artery

In the treatment of retroperitoneal sarcoma involving major vessels, complete resection with vascular reconstruction is challenging. We describe the case of a 72-year-old man who presented with 8 months of abdominal pain. Diagnostic workup revealed occlusion of the celiac trunk and the origin of the superior mesenteric artery due to a soft tissue sarcoma. Radical resection of the tumor and vessels was performed. Guided by intraoperative angiography, arterial reconstruction was performed without mesenteric ischemia. All arterial margins were negative. At the 6-year follow-up, the patient was alive with no evidence of recurrence.

Temporary Vascular Debranching to Facilitate Retroperitoneal Tumour en bloc Resection

Background

Oncovascular teams are known to be a cornerstone in planning and facilitating en bloc resection of large retroperitoneal masses. Vascular surgeons can help with dissection close to major vessels by vascular reconstruction when necessary, and also in performing specific procedures that can facilitate safe and optimal tumour mass resection. Two cases are reported where temporary vascular debranching of major arteries allowed safe tumour harvesting.

Case reports

A 68 year old man with a necrotic retroperitoneal carcinoma underwent en bloc resection with temporary debranching of the coeliac trunk, superior mesenteric artery, and right renal artery using a multibranched bypass from the axillary artery. The post-operative course included septic shock related to pulmonary infection requiring a 10 day stay in the intensive care unit (ICU). Renal function was normalised on day two. The patient was discharged on day 18. However, he died 78 months post-operatively from pulmonary metastases after anti-angiogenic treatment.

A 34 year old man with a retroperitoneal mature teratoma underwent en bloc resection with temporary debranching of the coeliac trunk, superior mesenteric artery, left and right renal arteries, and left and right common iliac arteries, with a multibranched bypass from the axillary artery. Post-operatively he required a five day stay in the ICU. Acute kidney injury (AKI) was noted, but it resolved without dialysis. The patient was discharged on day 16. After 78 months follow up he presented with chronic renal failure requiring dialysis. Follow up computed tomography angiography showed pulmonary metastases; although the metastases were manageable with surgical treatment, the patient refused further care.

Conclusions

Temporary extra-anatomical bypass from the axillary artery to the visceral arteries could be considered as an option to provide adequate perfusion and to prevent visceral ischaemia during en bloc resection of large retroperitoneal masses.

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Temporary axillary bypass protects target organs from the risk of ischaemia.

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Temporary axillary bypass allows tumour mobilisation without the risk of bleeding.

Primary angiosarcoma of aorta: A systematic review

PURPOSE

To elucidate the epidemiology, anatomical, presentation, classification, pathology, investigative modalities, management and prognosis of primary angiosarcoma of the aorta.

MATERIAL AND METHODS

A systematic review of literature from the database inception to January 2021 in PubMed and Embase, CINAHL and Cochrane Library in accordance to PRISMA was conducted. Retrieval and extraction was performed by two independent reviewers. The hierarchy of the evidence was assessed through the National Institute for Health and Care Excellence Checklist. Data were subjected to pooled prevalence analysis, Kaplan-Meier survival and test of probability using log-rank analysis. This review is registered with International Prospective Register of Systematic Reviews: RD42021231314.

RESULTS

82 studies with n = 123 cases met the inclusion criterion. Abdominal (45%) aorta was the commonest anatomical site with female predominance in ascending aorta (4:1) and aortic arch (2:1). The longest survival was in the ascending aorta and the shortest in the abdominal aorta [540 (interquartile range [IQR], 7-1560 days vs. 180 (IQR, 1-5730 days)], respectively. The overall median survival was 210 days (IQR, 1-5730 days) or 7 months. Lack of metastasis (47%) was a marker of longer survival (p < 0.03) irrespective of other attributes.

CONCLUSION

The pathophysiology appears to be a trend of increasing fatigue, fever and weight loss associated with segmental dysfunction of the aorta projecting occlusive or destructive phenotypes. Computed tomography angiography features of volume-occupying, bulky, polypoid (intraluminal), protrusive vegetation, hyper vascular without atherosclerotic lesions are extremely suggestive of PA of the aorta at 5th and 6th decades of life.

Clinical and Molecular Assessment of Patients with Lynch Syndrome and Sarcomas Underpinning the Association with MSH2 Germline Pathogenic Variants

Lynch syndrome (LS) is a hereditary cancer-predisposing syndrome associated most frequently with epithelial tumors, particularly colorectal (CRC) and endometrial carcinomas (EC). The aim of this study was to investigate the relationship between sarcomas and LS by performing clinical and molecular characterization of patients presenting co-occurrence of sarcomas and tumors from the LS spectrum. We identified 27 patients diagnosed with CRC, EC, and other LS-associated tumors who had sarcomas in the same individuals or families. Germline genetic testing, mismatch repair (MMR) protein immunohistochemistry, microsatellite instability (MSI), and other molecular analyses were performed. Five LS patients presenting personal or family history of sarcomas were identified (3 MSH2 carriers and 2 MLH1), with 2 having Muir-Torre phenotypes. For two MSH2 carriers we confirmed the etiology of the sarcomas (one liposarcoma and two osteosarcomas) as LS-related, since the tumors were MSH2/MSH6-deficient, MSI-high, or presented a truncated MSH2 transcript. Additionally, we reviewed 43 previous reports of sarcomas in patients with LS, which revealed a high frequency (58%) of MSH2 alterations. In summary, sarcomas represent a rare clinical manifestation in patients with LS, especially in MSH2 carriers, and the analysis of tumor biological characteristics can be useful for definition of tumor etiology and novel therapeutic options.