REVIEW ONCOLOGY

The prognostic significance of disseminated tumour cells in bone marrow in patients with operable breast cancer: An updated analysis

SUMMARY

The main cause of death in patients with breast cancer is the spread and outgrowth of tumour cells at distant sites. The presence of disseminated tumour cells (DTCs) in the bone marrow at diagnosis is a predictor for metastasis. This is an updated analysis of a prospective study in 100 patients with operable breast cancer on the long term-significance of bone marrow micrometastasis. The follow-up time ranges between one and 242 months, with a mean of 131 months and a median of 141 months. Bone marrow aspirates were analysed for the presence of DTCs by real-time polymerase chain reaction (RT-PCR) for cytokeratin 19 (CK19) and mammaglobin (MAM), as well as immunocytochemistry (ICC) for cytokeratin (CK). The aim of this study was to confirm the association between DTCs and disease-specific survival (DSS), as well as distant metastasis-free survival (DMFS).

CK19 positivity did not reach statistical significance for DSS (p=0.065) or DMFS (p=0.233). However, MAM positivity was significantly prognostic for DSS (HR: 5.583, p<0.001), but only borderline trending for DMFS (p=0.064). The combination of CK19 and MAM positivity, however, did confer a significantly increased risk for both DSS (HR: 3.073, p=0.003) and DMFS (HR: 3.150, p=0.023). ICC CK positivity significantly predicted DSS (HR: 3.868, p=0.040) or DMFS (HR: 3.868, p=0.040) when using a cut-off of ≥1 DTC. Stratifying the quantitative data also gave a significant result for DSS and DMFS (OR: 2.974, p=0.008). Combining both detection measurements using a cut-off of ≥1 DTC in immunochemical detection showed a significant association with DSS (HR: 3.213, p=0.089) and DMFS (HR: 4.984, p=0.015). Three negative parameters significantly predicted DSS (HR: 0.368, p= 0.017), but not DMFS. There was no statistically significant association of DTCs with organ-specific metastasis. This study supports the role of DTCs as a negative, prognostic factor in patients with operable breast cancer. The combination of multiple DTCs could be useful in identifying this increased risk.

(BELG J MED ONCOL 2023;17(3):71–84)

Value of testing for homologous recombination repair deficiency in newly diagnosed advanced-stage epithelial ovarian cancer: Recommendations for Belgian physicians

SUMMARY

Epithelial ovarian cancer (EOC) is the most frequent form of OC, a disease with a poor prognosis and high lethality, as most patients are diagnosed at advanced stages. To successfully battle EOC, it is crucial to identify reliable biomarkers and use personalised therapies in patient subgroups. A common feature of high-grade serous and endometrioid OC is homologous recombination repair deficiency (HRD), which frequently stems from the inactivation of the breast cancer susceptibility (BRCA) genes. Poly-(adenosine diphosphate [ADP])-ribose polymerase inhibitors (PARPi) were, therefore, developed for their lethality against HRD tumour cells. While patients with non-HRD tumours may also benefit from PARPi therapy in the recurrent EOC setting, recent phase III trials on newly diagnosed advanced-stage EOC have shown that PARPi treatment benefit is greater in patients with HRD tumours. These findings open new avenues for the use of PARPi as maintenance therapy in HRD-positive patients who had received first-line chemotherapy. This manuscript provides recommendations for Belgian physicians on how to approach HRD testing and incorporate it into treatment decisions of patients with newly diagnosed advanced-stage EOC.

(BELG J MED ONCOL 2023;17(2):38–45)

Cancer, chronic kidney disease and thrombosis

SUMMARY

Chronic kidney disease (CKD) and cancer are intertwined in many ways. In fact, cancer can cause CKD either directly or indirectly through the treatment adverse effects, while CKD may conversely be a risk factor for cancer. According to the Belgian Renal Insufficiency and Anticancer Medications (BIRMA) study, 64% of patients with cancer had a glomerular filtration rate (GFR) <90 ml/min/1.73m² and 16% of them presented with a mildly to severely decreased GFR (i.e.; <30 ml/min/1.73m² or 30–60 ml/min/1.73m²). As many anticancer drugs are predominantly excreted in the urine, tailoring the drug dose to the renal function of the individual patient is a crucial consideration. Furthermore, patients with cancer and CKD are also at an increased risk of thrombosis. Therefore, safe and effective drugs for the treatment and prevention of thrombotic events are necessary.

(BELG J MED ONCOL 2023;17(2):46–51)

Avoiding ‘whoops’ surgery in primary bone tumours in the spine: An intake protocol for all possibly involved caregivers in a tertiary hospital

SUMMARY

Primary bone tumours of the spine are relatively rare when compared to metastatic lesions and haematopoietic neoplasms. This often results in misdiagnosis leading to a high incidence of inadvertent intralesional surgery, which is associated in many cases with worse progression-free survival and overall survival. Based on evidence and consensus, a protocol was designed at the University Hospitals Leuven, intended to guide all possibly involved caregivers in different clinical situations. The protocol raises awareness of potentially suspicious situations and provides expert input to avoid unfortunate decisions, even in situations with alarming neurological deficits.

(BELG J MED ONCOL 2023;17(1):4–10)

Real-world evidence for implementation of new drugs

SUMMARY

Randomised clinical trials are still the gold standard when it comes to the development of new drugs. There are, however, important limitations to trials. Such as, patients included in clinical trials are often not representative of the general population, which limits the applicability of trial results in clinical practice. In this article, the advantages and disadvantages of observational data are discussed. For example, observational data are generally more representative of the general population and can include large numbers of patients. However, there are important biases that should be considered when performing observational studies. Of these, so-called ‘confounding by indication’ is the most important form of bias, which means that reasons for certain treatment allocations are also associated with outcomes of treatment, which can disrupt the analyses. In summary, real-world data can add to clinical trials, but bias in these studies cannot be completely resolved. For this reason, clinical trials remain essential and should attempt to use less stringent inclusion criteria in order to improve the generalisability of their results.

(BELG J MED ONCOL 2023;17(1):11–4)

The role of radiation therapy in pancreatic cancer management

SUMMARY

Treatment of pancreatic ductal adenocarcinoma (PDAC) has been the subject of controversy for decades. At the centre of this controversy is radiation therapy. Since PDAC is considered a systemic disease, the role of radiation therapy is debated. However, most of the available evidence is blurred by suboptimal radiation doses, less effective chemotherapy regimens and abandoned radiotherapy techniques. This article reviewed the available literature and discussed the changes in radiation therapy that have taken place over the past decade.

(BELG J MED ONCOL 2022;16(7):328–35)

Radiotherapy for metastatic colorectal cancer: When is it worth it?

SUMMARY

Colorectal cancer is a prevalent cancer in Belgium. Unfortunately, many of these patients will develop metastases at some point in their disease. However, given the new therapeutic options, the prognosis of these patients is better than before. Local ablation of metastases is among these therapeutic options. This concept of metastasis-directed therapy (MDT) is generally accepted for oligometastatic disease. It can be accomplished by a multitude of techniques, including surgery, radiofrequency and microwave ablation, but also radiotherapy (RT). This review addressed the rationale and application of RT within this context.

(BELG J MED ONCOL 2022;16(7):336–42)