Radiation and chemotherapeutics are associated with altered aortic aneurysm growth in cancer patients

Influence of a History of Malignancy on the Long-Term Survival of Abdominal Aortic Aneurysm Patients with Indication for an Elective Repair

BACKGROUND

The elective repair of aorto-iliac aneurysms (AAAs) in patients with a cancer history is sometimes controversial. Our aim was to evaluate the relationship between the history of a solid tumor and the long-term survival of patients with an AAA within therapeutic range.

METHODS

The consecutive series of patients with an intact AAA within therapeutic range attended in a tertiary hospital (2008-2021) was evaluated. Collected variables included clinical and cancer characteristics, such as time since treatment, location, and extension. The association between cancer history and survival was evaluated with Cox models adjusted by age, sex, the Charlson comorbidity index, and aneurysm treatment.

RESULTS

The study included 416 patients (mean age 75.2 years; 92.2% male; 314 AAA electively treated). Among them, 117 had a history of a solid tumor (61 genitourinary, 30 digestive, and 22 respiratory), 54 were active or treated <6 months, 12 had metastases, and 8 were under palliative care. During follow-up, 248 (59.6%) patients died. Patients with nonadvanced urological cancer had similar survival than those without cancer, while only those with an advanced cancer (metastasis or palliative care) or a currently treated nonurological solid tumor had lower life expectancy (hazard ratio = 1.84, P = 0.04). All AAA patients, regardless their cancer history, had lower survival rates when compared with an age- and sex-matched population.

CONCLUSION

Patients with AAA have a limited life expectancy and a prior cancer history does not commonly worsen their prognosis. Patients with an advanced or a current nonurological cancer had lower survival rates, so in these cases AAA decision-making should be individualized.

Abdominal aortic aneurysm histomorphology shows different inflammatory aspects among patients and is not associated with classic risk factors - the HistAAA study

AIMS

Abdominal aortic aneurysm (AAA) treatment is upon a diameter threshold. Attempts for medical growth abrogation have failed thus far. This study aims to elucidate the heterogeneity of AAA histomorphology in correlation to individual patient and aneurysm metrics.

METHODS AND RESULTS

Samples from the left anterior aneurysm wall underwent histologic analysis including angiogenesis, calcification, fibrosis, type and grade of inflammation in adventitia and media. Clinical information and state of aneurysm (intact, symptomatic, ruptured, inflammatory) were retrieved. Semi-automated geometric analysis (Endosize©, Therenva) and finite element methods (A4Clinics© Research Edition, Vascops GmbH) were included.364 patients' samples (85.4% male, median age 69 years) were scored for acute or chronic inflammation, both not associated with rupture (52x), symptomatic disease (37x) or diameter (57 [52-69] mm; p = 0.87). The degree of fibrosis and the presence of angiogenesis were significantly higher (both p < 0.001) with increasing inflammation, which in turn significantly decreased with patient age (est = - 0.015/year, p = 0.017). No significant differences were seen for acute (vs. elective), male (vs. female) or diabetic patients. Aneurysm geometry (n=252) or annual growth rate (n=142) were not associated with histologic characteristics. Yet, local luminal thrombus formation was significantly higher with increasing inflammation (p = 0.04).

CONCLUSION

Type and degree of inflammation are the most distinguishable histologic characteristics in the AAA wall between individual patients, yet are not associated with diameter or rupture. Local luminal thrombus formation is associated with inflammatory features and suggests a vivid bio-physical compartment with intra-individual age-dependent differences.

Deciphering Popliteal Artery Aneurysm Patient Diversity: Insights From a Cluster Analysis of the POPART Registry

BACKGROUND

Popliteal artery aneurysms (PAAs) are the most common peripheral aneurysm. However, due to its rarity, the cumulative body of evidence regarding patient patterns, treatment strategies, and perioperative outcomes is limited. This analysis aims to investigate distinct phenotypical patient profiles and associated treatment and outcomes in patients with a PAA by performing an unsupervised clustering analysis of the POPART (Practice of Popliteal Artery Aneurysm Repair and Therapy) registry.

METHODS AND RESULTS

A cluster analysis (using k-means clustering) was performed on data obtained from the multicenter POPART registry (42 centers from Germany and Luxembourg). Sensitivity analyses were conducted to explore validity and stability. Using 2 clusters, patients were primarily separated by the absence or presence of clinical symptoms. Within the cluster of symptomatic patients, the main difference between patients with acute limb ischemia presentation and nonemergency symptomatic patients was PAA diameter. When using 6 clusters, patients were primarily grouped by comorbidities, with patients with acute limb ischemia forming a separate cluster. Despite markedly different risk profiles, perioperative complication rates appeared to be positively associated with the proportion of emergency patients. However, clusters with a higher proportion of patients having any symptoms before treatment experienced a lower rate of perioperative complications.

CONCLUSIONS

The conducted analyses revealed both an insight to the public health reality of PAA care as well as patients with PAA at elevated risk for adverse outcomes. This analysis suggests that the preoperative clinic is a far more crucial adjunct to the patient's preoperative risk assessment than the patient's epidemiological profile by itself.

Appropriate management of the small abdominal aortic aneurysm

There is variation in the management of small aneurysms in the United States today, with some surgeons moving forward with elective repair and others practice ongoing surveillance. Literature exists to suggest that small aneurysms are repaired at a higher rate than should be considered acceptable, and this represents a deviation from current standards of care. To best understand the optimal care of this patient population, this article aims to evaluate the current management of small aneurysms, review contemporary guidelines and the literature behind them, and assess the appropriateness of surgical management of small aneurysms.

Radiation therapy for cancer is potentially associated with reduced growth of concomitant abdominal aortic aneurysm

PURPOSE

Co-prevalence of abdominal aortic aneurysm (AAA) and cancer poses a unique challenge in medical care since both diseases and their respective therapies might interact. Recently, reduced AAA growth rates were observed in cancer patients that received radiation therapy (RT). The purpose of this study was to perform a fine-grained analysis of the effects of RT on AAA growth with respect to direct (infield) and out-of-field (outfield) radiation exposure, and radiation dose-dependency.

METHODS

A retrospective single-center analysis identified patients with AAA, cancer, and RT. Clinical data, radiation plans, and aneurysm diameters were analyzed. The total dose of radiation to each aneurysm was computed. AAA growth under infield and outfield exposure was compared to patients with AAA and cancer that did not receive RT (no-RT control) and to an external noncancer AAA reference cohort.

RESULTS

Between 2003 and 2020, a total of 38 AAA patients who had received well-documented RT for their malignancy were identified. AAA growth was considerably reduced for infield patients (n = 18) compared to outfield patients (n = 20), albeit not significantly (0.8 ± 1.0 vs. 1.3 ± 1.6 mm/year, p = 0.28). Overall, annual AAA growth in RT patients was lower compared to no-RT control patients (1.1 ± 1.5 vs. 1.8 ± 2.2 mm/year, p = 0.06) and significantly reduced compared to the reference cohort (1.1 ± 1.5 vs. 2.7 ± 2.1 mm/year, p < 0.001). The pattern of AAA growth reduction due to RT was corroborated in linear regression analyses correcting for initial AAA diameter. A further investigation with respect to dose-dependency of radiation effects on AAA growth, however, revealed no apparent association.

CONCLUSION

In this study, both infield and outfield radiation exposure were associated with reduced AAA growth. This finding warrants further investigation, both in a larger scale clinical cohort and on a molecular level.

Editor's Choice -- European Society for Vascular Surgery (ESVS) 2024 Clinical Practice Guidelines on the Management of Abdominal Aorto-Iliac Artery Aneurysms

OBJECTIVE

The European Society for Vascular Surgery (ESVS) has developed clinical practice guidelines for the care of patients with aneurysms of the abdominal aorta and iliac arteries in succession to the 2011 and 2019 versions, with the aim of assisting physicians and patients in selecting the best management strategy.

METHODS

The guideline is based on scientific evidence completed with expert opinion on the matter. By summarising and evaluating the best available evidence, recommendations for the evaluation and treatment of patients have been formulated. The recommendations are graded according to a modified European Society of Cardiology grading system, where the strength (class) of each recommendation is graded from I to III and the letters A to C mark the level of evidence.

RESULTS

A total of 160 recommendations have been issued on the following topics: Service standards, including surgical volume and training; Epidemiology, diagnosis, and screening; Management of patients with small abdominal aortic aneurysm (AAA), including surveillance, cardiovascular risk reduction, and indication for repair; Elective AAA repair, including operative risk assessment, open and endovascular repair, and early complications; Ruptured and symptomatic AAA, including peri-operative management, such as permissive hypotension and use of aortic occlusion balloon, open and endovascular repair, and early complications, such as abdominal compartment syndrome and colonic ischaemia; Long term outcome and follow up after AAA repair, including graft infection, endoleaks and follow up routines; Management of complex AAA, including open and endovascular repair; Management of iliac artery aneurysm, including indication for repair and open and endovascular repair; and Miscellaneous aortic problems, including mycotic, inflammatory, and saccular aortic aneurysm. In addition, Shared decision making is being addressed, with supporting information for patients, and Unresolved issues are discussed.

CONCLUSION

The ESVS Clinical Practice Guidelines provide the most comprehensive, up to date, and unbiased advice to clinicians and patients on the management of abdominal aorto-iliac artery aneurysms.

Pathogenesis and management of abdominal aortic aneurysm

Abdominal aortic aneurysm (AAA) causes ∼170 000 deaths annually worldwide. Most guidelines recommend asymptomatic small AAAs (30 to <50 mm in women; 30 to <55 mm in men) are monitored by imaging and large asymptomatic, symptomatic, and ruptured AAAs are considered for surgical repair. Advances in AAA repair techniques have occurred, but a remaining priority is therapies to limit AAA growth and rupture. This review outlines research on AAA pathogenesis and therapies to limit AAA growth. Genome-wide association studies have identified novel drug targets, e.g. interleukin-6 blockade. Mendelian randomization analyses suggest that treatments to reduce low-density lipoprotein cholesterol such as proprotein convertase subtilisin/kexin type 9 inhibitors and smoking reduction or cessation are also treatment targets. Thirteen placebo-controlled randomized trials have tested whether a range of antibiotics, blood pressure-lowering drugs, a mast cell stabilizer, an anti-platelet drug, or fenofibrate slow AAA growth. None of these trials have shown convincing evidence of drug efficacy and have been limited by small sample sizes, limited drug adherence, poor participant retention, and over-optimistic AAA growth reduction targets. Data from some large observational cohorts suggest that blood pressure reduction, particularly by angiotensin-converting enzyme inhibitors, could limit aneurysm rupture, but this has not been evaluated in randomized trials. Some observational studies suggest metformin may limit AAA growth, and this is currently being tested in randomized trials. In conclusion, no drug therapy has been shown to convincingly limit AAA growth in randomized controlled trials. Further large prospective studies on other targets are needed.

Cancer, cancer treatment and aneurysmatic ascending aorta growth within a retrospective single center study

Background: Multi-morbidity poses a substantial challenge for health care in an aging population. Recent studies did not provide evidence for general side effects of anti-cancer therapy regarding the growth rate of coincident abdominal aortic aneurysms, although it was suggested that specific therapeutic substances might accelerate growth. Aneurysm pathology, however, differs with respect to localization. Hence, we present the first ever analysis on the association of cancer and cancer therapy with growth alteration of aneurysms of the ascending aorta (AscAA). Patients and methods: A retrospective single-center identification of AscAA+cancer patients was performed in the institutional picture archiving and communication system (PACS). Included were all patients with ≥2 CT angiograms over ≥6 months and additional malignancy. Clinical data and aneurysm diameters were retrieved and analyzed for an association of cancer (stratified by tumor entity) or cancer therapy (stratified by several classes of chemotherapeutic agents and radiation therapy) with annual growth rate, respectively. Statistics included t-test, Wilcoxon test, and a linear regression model accounting for initial AscAA diameter and type of treatment. Results: From 2003 to 2021, 151 patients (median age 70 years; 85% male) with AscAA and coincident 163 malignancies were identified. Prostate (37%) and hematologic cancer (17%) were most frequent. One-hundred-eleven patients (74%) received chemotherapy and 75 patients (50%) had radiation. After exclusion of six patients with an initial AscAA diameter >55 mm, the average annual AscAA growth rate was 0.18±0.64 mm/year, with only 12 patients experiencing a growth rate >1mm/year. Neither tumor entity nor radiation or chemotherapy - alone or in combination - were significantly associated with an alteration of the annual AscAA growth rate. Likewise, a subanalysis for singular chemotherapeutic agents did not reveal a specific association with AscAA growth alteration. Conclusions: Growth rates of AscAA are low in this cohort with coincident malignancy. Cancer and/or chemotherapy or radiation are not associated with an alteration of the annual growth rate. Additional control examinations seem unnecessary.