Keywords
c-TACE - neuroendocrine liver metastases - microwave ablation (MWA) - laser interstitial
thermotherapy (LITT)
Abbreviations
NELM:
Neuroendocrine liver metastasis
c-TACE:
Conventional transarterial chemoembolization
MWA:
Microwave ablation
LITT:
Laser interstitial thermotherapy
NET:
Neuroendocrine tumor
RFA:
Radiofrequency ablation
TAE:
Transarterial embolization
VR:
Volume reduction
CT:
Computed tomography
MRI:
Magnetic resonance imaging
OS:
Overall survival time
mOS:
Median overall survival
SR:
Survival rate
CA:
Complete ablation
NEC:
Neuroendocrine carcinoma
CUP:
Cancer of unknown primary
Introduction
With an incidence of 5–7 cases per 100,000, gastropancreatic neuroendocrine neoplasms
show the second highest prevalence among gastrointestinal cancers today [1]. Neuroendocrine liver metastases (NELMs) occur in 28–75 % of patients with neuroendocrine
tumors (NETs) [2] and NELMs severely reduce life expectancy. For example, patients with NETs of the
small intestine without NELMs showed an estimated survival of 176.3 ± 30.3 months,
whereas patients with NELMs had a survival of 98.1 ± 8.1 months [3]. Various procedures are available for the treatment of NELMs. The best curative
method in terms of survival is liver resection, but according to the latest ENETS
guidelines, only 20–57 % of patients can be treated this way [4]. Since symptoms in neuroendocrine tumors often appear very late and nonspecifically,
a disseminated stage of disease is often already present, which reduces the chance
of surgical treatment [5]. Therefore, other therapy methods for non-resectable liver metastases play an important
role. These therapeutic procedures include drug therapy, nuclear medicine approaches
(such as peptide radio receptor therapy, selective intra-arterial radiotherapy [SIRT
or TARE]), and interventional radiological therapies. These interventional radiological
therapies can be further divided into local ablations (microwave ablation [MWA], radiofrequency
ablation [RFA], laser interstitial thermotherapy [LITT]) and transarterial therapies
(conventional transarterial chemoembolization [c-TACE], transarterial embolization
[TAE]) [6]. Following the guidelines of the Arbeitsgemeinschaft der Wissenschaftlichen Medizinischen Fachgesellschaften (AWMF), local ablation is recommended for unresectable liver metastases with an oligometastasis
(≤ 5 metastases) with a diameter of ≤ 5 cm. Embolization therapy (TAE/TACE) of the
liver can be performed in symptomatic NETs, with the presence of multiple unresectable
liver metastases, but also in case of asymptomatic NELMs with hepatic progression
[7].
Numerous studies have shown that these interventional therapies have significantly
improved the survival and well-being of patients [3]
[6]
[7]. Most data published to date relates to RFA [6], while there are only a few publications on MWA and LITT [7]. In addition, there are few studies that examine the application of interventional
therapies in more detail. It is important to investigate whether there are factors
that influence the success of c-TACE therapy in terms of volume reduction (VR) and
how VR of the lesions varies over the course of c-TACE therapy. The aim of this study
was to retrospectively identify prognostic factors for patients with NELMs undergoing
interventional therapies and to determine the most effective therapy in terms of VR
and survival.
Materials and Methods
This retrospective cohort study was approved by the institutional review board (IRB)
with a waiver for written informed consent.
Patient selection
130 patients (82 men, 48 women) who received NELM treatment between 1996 and 2020
were retrospectively evaluated. The mean age was 59.0 years (range 24.6–87.0 years)
([Table 1]). The number of liver lesions per patient ranged from 1 to > 100 lesions. The diameter
of the lesions ranged from 0.2–17 cm. Ablations were performed in oligometastatic
(≤ 5 metastases) patients with lesions with a diameter of ≤ 5 cm. 40 patients (24
LITT, 19 MWA, 3 LITT and MWA) were treated with a thermoablative procedure. In the 24 LITT patients, a total
of 82 lesions were treated in 69 interventions. In the 19 MWA patients, 63 lesions
were treated in 62 interventions.
Table 1
Baseline characteristics.
|
Parameters
|
n = 130 patients
|
|
Mean age/range
|
59.0 years/24.6–87.0 years
|
|
Gender, male/female
|
82/48
|
|
Treatment
|
|
|
|
89
|
|
|
16
|
|
|
20
|
|
|
5
|
|
Primary tumor
|
|
|
|
6
|
|
|
28
|
|
|
8
|
|
|
37
|
|
|
9
|
|
|
42
|
|
Number of c-TACE interventions, n
|
|
|
|
25
|
|
|
8
|
|
|
22
|
|
|
14
|
|
|
5
|
|
|
9
|
|
|
4
|
|
|
7
|
|
|
3
|
|
|
5
|
|
|
23
|
|
|
6.25
|
|
|
4
|
|
Days between c-TACE interventions (mean/median)
|
83.7/35
|
|
Liver lesions, n
|
|
|
|
12
|
|
|
28
|
|
|
88
|
|
|
2
|
c-TACE was performed in patients with symptomatic NELMs or with the presence of multiple
unresectable NELMs. c-TACE was also performed in the neoadjuvant context: In patients
who had > 5 lesions, the use of c-TACE could reduce the number of lesions to ≤ 5.
Thus, these patients could now undergo thermal ablation. All patients were discussed
in a multidisciplinary tumor board. All included patients were not amenable to surgery
or refused surgery.
c-TACE
A total of 813 c-TACE procedures were performed on the 130 patients. Patients who
underwent only one c-TACE procedure were not included in the tumor VR analysis.
After a catheter was inserted into the common femoral artery using the Seldinger technique,
an angiography examination of the abdominal arterial vasculature was performed. Then
a microcatheter was positioned through the celiac trunk into the common hepatic artery.
Depending on which NELM was to be treated, the microcatheter was advanced into either
the right or left hepatic artery or into a segmental artery. Once the correct location
was confirmed, chemotherapeutic agents and embolization material were injected into
the target artery.
MWA
MWA was performed using a CT–guided percutaneous approach under analgo-sedation. The
first MWA was carried out in October 2009. The systems used for ablation were Covidien
(Medtronic, Minneapolis, USA), Amica (Amica Hospital Service, Aprilia, Italy), and
Microsulis (Microsulis Medical Limited, Waterlooville, UK).
LITT
LITT was performed from 1996 to 2009. Due to the high material and personnel expenditure,
the procedure was then replaced by MWA. First, metastases were localized with a CT
examination and the laser application set was introduced using local anesthesia. Then
the patients were transferred to an MRI scanner where the actual ablation took place.
LITT was performed using a Nd:YAG-laser (Dornier MedLas 5060 and 5100) with a bare
fiber (400μm). The laser application kit (SOMATEX, Berlin, Germany) consisted of a
cannulation needle, guide wire, a sheath system, and a special protective catheter
[6].
Imaging
To evaluate c-TACE interventions, a 1.5 Tesla MRI scanner and a 256 row CT scanner
were used. Before the first c-TACE procedure, a non-enhanced and a contrast-enhanced
MRI examination was performed. In all subsequent c-TACE interventions, a preinterventional
MRI examination without contrast enhancement was performed. After each c-TACE, a CT
scan was performed to assess the retention of lipiodol and to detect misdirected lipiodol.
To evaluate and control MWA and LITT, patients received an MRI scan before and after
the intervention. For follow-up, MRI scans were performed every 3 months in the first
year and every 6 months thereafter.
The volume of the reference lesions was determined by the sum of the area of the lesions
in the individual layers multiplied by the layer thickness. The ablation margin was
considered sufficient if the ablation zone exceeded the NELM by at least 5 mm.
Statistical analysis
Descriptive statistics were performed with BiAS, survival analysis with MedCalc. The
mixed-effects model for VR analysis was calculated with R.
For survival analysis and to determine predictors of death, patients were divided
into different cohorts according to the following parameters: sex, age at the beginning
of treatment (20–39, 40–59, ≥ 60 years), therapeutic intention (curative, palliative,
symptomatic), number of liver lesions (1–2, 3–9, ≥ 10), and location of the primary
(foregut, midgut, hindgut, pancreas, lung, and other origin) ([Fig. 1]).
Fig. 1 Patient selection and analyses performed.
Abb. 1 Patientenauswahl und durchgeführte Analysen.
The classification considering the therapeutic intention was based on the following
criteria: The aim of the curative treatment was the complete eradication of liver metastases in patients who had no
other extrahepatic metastases. Patients categorized as palliative had extrahepatic metastases or a high tumor burden in the liver. The goal of palliative
treatment was to prolong their survival and achieve a stable disease. Patients were
categorized as symptomatic if they showed symptoms which was usually associated with a massive intrahepatic
tumor load (> 50 % of the liver).
The parameter “therapeutic intention” was additionally investigated in more detail.
It was analyzed how many patients, depending on their therapeutic category, had a
response to c-TACE and whether the therapeutic intention would change over the course.
Response to c-TACE meant that the treatment criteria for local ablation (oligometastasis,
diameter ≤ 5 cm) were achieved with c-TACE therapy.
Additionally, survival depending on therapy was analyzed. All survival analyses were
done using the Kaplan-Meier method, the logrank test, and Cox regression analysis.
Four patients who only visited our radiological institute once were excluded from
survival analysis.
Overall survival time (OS) was determined from the time of first interventional treatment
until death or last follow-up. Patients alive at the time of the last follow-up were
censored.
Because of the simultaneous analysis of locoregional ablations and c-TACE, different
numbers of lesions were evaluated in patients. Therefore, a mixed-effects model was
used for the evaluation of c-TACE volume reduction: The investigated parameters were
the drugs used for c-TACE (gemcitabine, irinotecan, other drugs), the site of the
primary (foregut, midgut, hindgut, pancreas, lung, other), the therapeutic intention
(curative, palliative, symptomatic), whether there was a break of treatment longer
than 90 days between two c-TACE procedures, and whether the liver had been treated
with c-TACE before treating the reference lesion. The last parameter was assessed
because in some cases lesions occurred in the later course of c-TACE therapy, for
example, after the 5th c-TACE intervention, or were not treated before because the
liver segment containing the reference lesion was not treated during the prior interventions.
Accordingly, patients were divided into three groups depending on how many c-TACE
procedures had been performed prior to the treatment of the reference lesion: 1–4,
5–9 or ≥ 10 c-TACE procedures.
For the assessment of thermoablative procedures regarding complications and complete
ablation, descriptive statistics, Chi2-test, and Fisher’s exact test were used. Complications were divided according to
the CIRSE classification system [8].
Results
Survival analysis
The median overall survival (mOS) of all 126 patients that could be evaluated for
survival was 38.4 months (95 %CI 22.8–55.1). The 1, 2, 3 and 5-year survival rates
(SR) were 75 %, 58 %, 51 %, and 36 %, respectively. Regarding survival depending on
therapy, patients who only underwent c-TACE showed an mOS of 19.6 months (95 %CI 13.8–35.5),
a one-year SR of 65 %, and a five-year SR of 31 %. Patients who received subsequent
MWA had an mOS of 37.2 months (95 %CI 29.4–54.4), a one-year SR of 93 %, and a five-year
SR of 32 %. Patients who received subsequent LITT showed an mOS of 54.1 months (95 %CI
34.3–93.9), a one-year SR of 100 %, and a five-year SR of 40 %. However, no statistically
significant difference in survival between MWA, LITT, and c-TACE was found (p = 0.0703).
([Table 2])
Table 2
Survival depending on treatment.
|
n
|
Mean [month]
|
Median [month]
|
1 yr-sr [%]
|
5 yr-sr [%]
|
|
Only c-TACE
|
85
|
42.882
|
19.561
|
65
|
31
|
|
c-TACE and only MWA
|
16
|
40.702
|
37.249
|
93
|
32
|
|
c-TACE and only LITT
|
20
|
89.291
|
54.082
|
100
|
40
|
Statistically significant differences in survival were found for the parameters: number
of liver lesions and therapeutic intention. The group of ≥ 10 liver lesions differed
significantly from 1–2 liver lesions (p = 0.0019, HR = 0.27, 95 %CI 0.12–0.62) and
from 3–9 liver lesions (p = 0.0008, HR = 0.35, 95 %CI 0.19–0.65). Regarding the therapeutic
intention, all groups differed significantly from each other ([Fig. 2]). The curative group had a significantly longer survival than the palliative group
(p = 0.0387, HR = 2.35, 95 %CI 1.0452–5.2768) and the symptomatic group (p < 0.0001,
HR = 6.27, 95 %CI 2.70–14.50). The palliative group had a significantly longer survival
than the symptomatic group (p < 0.0001, HR = 2.67, 95 %CI 1.69–4.22).
Fig. 2 Kaplan-Meier analysis comparing the OS of the three cohorts curative, palliative,
and symptomatic.
Abb. 2 Kaplan-Meier-Analyse mit Vergleich der Überlebenszeiten der drei Kohorten kurativ,
palliativ und symptomatisch.
No statistical significance (p > 0.05) was identified regarding the parameters: sex
(p = 0.393), location of the primary (p = 0.397), and age (p = 0.491).
Course of disease depending on therapeutic intention
In the curative cohort, response to c-TACE was achieved in 90.9 % of patients (10/11).
In the palliative cohort, response was reached in 43.6 % of patients (31/71). Nevertheless,
7 of 11 (63.6 %) initially curative patients ended up in the palliative group, while
13 of 71 (18.3 %) initially palliative patients were finally given curative therapy.
All patients classified as symptomatic remained in this group for the entire course
of therapy ([Table 3]).
Table 3
Response to c-TACE and survival according to therapeutic intention.
|
n
|
Response to c-TACE
|
Therapeutic intention in the course
|
Median OS
|
95 % CI for OS
|
|
Curative
|
11
|
10 (90.9 %)
|
Curative: 4
Palliative: 7
|
106.9 months
|
81.3–156.5
|
|
Palliative
|
71
|
31 (43.6 %)
|
Curative: 13
Palliative: 58
|
45.5 months
|
34.3–59.4
|
|
Symptomatic
|
48
|
0 (0 %)
|
Symptomatic: 48
|
9.4 months
|
4.5–19.3
|
Evaluation of tumor volume reduction – c-TACE
VR of the reference lesions was achieved in 65 % of patients. The median VR was 23.5 %
([Fig. 3]). With respect to whether the liver was already treated with c-TACE before the treatment
of the reference lesion, a statistically significant correlation was determined in
the mixed-effects model. The group “≥ 10 c-TACE procedures” differed significantly
from the group “1–4 c-TACE procedures” (p = 0.026, OR = 4.689, 95 %CI 1.20–18.25).
For the group of 1–4 c-TACE procedures, VR was demonstrated in 69 % of reference lesions,
whereas for the group of ≥ 10 c-TACE procedures, VR was achieved in only 35 %. Treatment
interruptions of longer than 90 days (e. g., due to a wait-and-see therapy strategy,
intermediate remission, or scheduling reasons on the part of the patient) were also
associated with a negative outcome regarding VR (p = 0.052, OR = 3.150, 95 %CI 0.990–10.018).
No significant association was shown for the therapeutic intention, location of primary,
and drugs used in c-TACE.
Fig. 3 Example of c-TACE and MWA in the treatment of a 24-year-old male with two NELMs from
an NET of the small intestine. In total, the patient received 8 c-TACE and 2 MWA treatments
resulting in complete hepatic remission. (a) Two years after small intestinal resection, the patient shows the reference lesion
in segment 4/2 and another lesion in segment 7. (b) Axial CT after eight c-TACE interventions showing a total volume reduction of 80 %
of the reference lesions (upper arrow). Detection of lipiodol in the lesions (arrows).
(c) Axial CT showing the process of MWA with the ablation antenna placed inside the
reference lesion in segment 4/2 (arrow). (d) Axial contrast-enhanced T1-weighted MRI after first MWA. Complete ablation of the
reference lesion within the necrosis zone (upper arrow) and one last persistent lesion
in segment 7 (lower arrow). (e) Axial CT showing the process of the second MWA with the ablation antenna placed
inside the lesion in segment 7 (arrow). (f) Axial non-enhanced T1-weighted MRI after second MWA of the last remaining lesion
in segment 7 showing the necrosis zones (arrows) and resulting in complete hepatic
remission.
Abb. 3 Beispiel für c-TACE und MWA bei der Behandlung eines 24-jährigen Mannes mit zwei
NELM eines NET des Dünndarms. Insgesamt erhielt der Patient 8 c-TACE und 2 MWA, was
zu einer vollständigen Remission der Leber führte. (a): Zwei Jahre nach der Dünndarmresektion zeigt der Patient die Referenzläsion in Segment
4/2 und eine weitere Läsion in Segment 7. (b) Axiales CT nach acht c-TACE-Eingriffen mit einer Volumenreduktion der Referenzläsion
von insgesamt 80 % (oberer Pfeil). Nachweis von Lipiodol in den Läsionen (Pfeile).
(c) Axiales CT, das den Verlauf der MWA zeigt, wobei die Ablationsantenne innerhalb
der Referenzläsion im Segment 4/2 platziert ist (Pfeil). (d) Axiales T1-gewichtetes MRT mit Kontrastmittel nach der ersten MWA. Vollständige
Ablation der Referenzläsion innerhalb der Nekrosezone (oberer Pfeil) und eine letzte
persistierende Läsion im Segment 7 (unterer Pfeil). (e) Axiales CT, das den Verlauf der zweiten MWA zeigt, wobei die Ablationsantenne innerhalb
der Läsion in Segment 7 platziert ist (Pfeil). (f) Axiales T1-gewichtetes MRT nach der zweiten MWA der letzten verbleibenden Läsion
in Segment 7 mit Darstellung der Nekrosezonen (Pfeile) und anschließender vollständiger
hepatischer Remission.
In addition, it was investigated whether the effect of the individual c-TACE interventions
changed during the course of c-TACE therapy. The number of c-TACE interventions per
patient ranged from 1–26 interventions. Despite c-TACE therapy, patients on average
showed intrahepatic disease progression after the 6th intervention ([Table 4]). Therefore, from the 7th intervention onwards the proportion of interventions, in which a VR was achieved
through c-TACE therapy, was always smaller than or equal to the proportion of volume
increase. For example, 18 lesions that were treated with ≥ 7 c-TACE procedures were
evaluated in this study. After the seventh c-TACE intervention, increased lesion volume
was detected in 56 % of lesions (n = 10). A VR was detected in only 44 % of the lesions
(n = 8). Also, after the 8th to 10th c-TACE intervention, a larger lesion volume was
detected in the majority of lesions after c-TACE than before c-TACE. In contrast,
after the first 6 c-TACE procedures, a VR was detected in the majority of cases ([Table 4]).
Table 4
C-TACE volume reduction of lesions in the course of c-TACE therapy.
|
c-TACE no.
|
1
|
2
|
3
|
4
|
5
|
6
|
7
|
8
|
9
|
10
|
|
Number of lesions evaluated
|
97
|
74
|
60
|
43
|
31
|
24
|
18
|
14
|
8
|
7
|
|
% of lesions with volume reduction
|
59
|
53
|
65
|
58
|
45
|
67
|
44
|
36
|
50
|
43
|
|
% of lesions with volume increase
|
39
|
46
|
33
|
40
|
55
|
29
|
56
|
64
|
50
|
57
|
|
% of lesions with constant volume
|
2
|
1
|
2
|
2
|
0
|
4
|
0
|
0
|
0
|
0
|
Evaluation of tumor volume reduction – thermoablative interventions
Complete ablation (CA) after LITT was found in 68 of 71 evaluable lesions (95.7 %).
CA by MWA was observed in 54 out of 60 lesions (90 %) ([Fig. 3]). For 2 of the 6 lesions that were not completely ablated, it must be noted that
these 2 lesions were too large for CA and were only supposed to be reduced in size.
Excluding these two lesions, the percentage of CA is 93.1 %.
No statistically significant difference was demonstrated between MWA and LITT with
respect to complete ablation (Fisher’s exact test: p = 0.70).
64 of 69 LITT interventions could be evaluated regarding complications. Minor complications
occurred in 12 interventions (18.8 %): 8 pleural effusions (Cirse Grade 1), 1 case
of edema of adjacent structures (Grade 1), 2 subcapsular hematomas (Grade 2), and
1 bilioma (Grade 2). One hepatic abscess as a major complication was reported (Grade
3). Regarding MWA, 58 of 62 interventions could be evaluated for complications. Mild
complications occurred in 5 cases (8.6 %): 2 pleural effusions (Grade 2), 1 hemorrhage
(Grade 2), 1 case of edema (Grade 1), and 1 case of air trapping (Grade 1).
With regard to complications, a statistical trend for MWA with fewer complications
than LITT was shown, although no statistical significance was demonstrated (p = 0.07,
Chi2-test = 3.31).
Discussion
The aim of this study was to identify prognostic factors for patients with NELMs undergoing
radiological interventional therapies and to determine the most effective therapy
in terms of VR and survival. Significant prognostic factors for survival were number
of liver lesions and therapeutic intention. No statistical significance was identified
for the parameters: sex, age, and location of the primary. In contrast, Barat et al.
described that a pancreatic primary, an unknown primary site, and male gender are
associated with a shortened survival [9]. Our study also showed that the therapeutic intention for symptomatic patients cannot
be changed to a palliative or curative treatment option, but a change from palliative
to curative intention and vice versa is quite possible. In 2016, Vogl et al. investigated
the SR depending on the clinical indication (curative vs. palliative) in patients
with general liver lesions treated with MWA. In this study, no significant difference
was shown between the curative and the palliative group, whereas curative treatment
intention was associated with a significantly longer life in our study [10]. One explanation may be that Vogl assessed only MWA patients and liver lesions of
different origin.
Assessing survival depending on therapy, no statistically significant difference was
found. However, the one-year SR of the c-TACE group differed considerably from the
two other groups, but the 5-year SR (31 %) was quite similar. The literature contains
very different data on the 5-year SR of NELM patients treated with c-TACE. In a review
from 2020, the 5-year SR ranged from 19 % to 50 % [11]. Following Mayo et al., one explanation for the different data on SR may be the
great heterogeneity of the patients and the fact that different institutes treat cases
of different severity [12].
Regarding VR and complications of thermoablative procedures in NELMs, data is still
lacking [13]. Perrodin et al. examined MWA for 40 liver malignant lesions, including 17 NELMs
[13]. Here, CA was seen in 97.5 % and mild complications in 12 % of cases. Martin et
al. described a CA rate in 90 % of cases [14]. Thus, these studies showed a similar trend for MWA for CA and complications. For
LITT, Peräla described in a case report two LITT patients with NELMs [15]. One patient had minor complications. The total survival was 21 and 13 years.
In contrast to MWA and LITT, there are already many papers that have investigated
the general outcome of TACE or TAE. In 2021, Clift et al. summarized the results of
studies regarding TAE and TACE therapies for NELMs [16]. However, there are still only a few studies that have assessed c-TACE therapy in
more detail regarding VR and how the VR of the lesions varies over the course of multiple
c-TACE procedures. For patients with HCC, Breunig et al. investigated the course of
TACE therapy (comprising 1–10 TACE procedures), in terms of expenses and survival
[17]. Wang et al. investigated the effect of different numbers of TACE procedures on
liver function in HCC patients with transjugular intrahepatic portosystemic shunt
[18]. Thus, there are few papers that describe the course of TACE therapy in more detail,
and mainly for HCC. Our study demonstrated that VR was achieved significantly more
often when a lesion was treated at the beginning of multiple c-TACE procedures and
that efficacy of c-TACE decreases after the 6th intervention. Furthermore, it has
been shown that VR due to c-TACE is particularly effective when there is no treatment
break longer than 90 days between interventions (p = 0.052). It can be assumed that
patients should be closely monitored to treat lesions as early as possible in the
case of reappearance.
In this study there are several limitations: NENs are a very heterogeneous tumor type
with sometimes very rare entities with different therapeutic options. A precise classification
of the different tumors with respect to the exact primary and grading would be very
important to make the data more comparable and to derive more differentiated results.
In the present study, no classification of tumors by grading (G1 vs. G2 vs. G3. vs.
NEC, Ki67) was performed, as no data were available due to the retrospective nature
of the study. Furthermore, it should be noted that the classification on Ki67 was
introduced with the ENETS guidelines of 2006/2007, but the data of the study date
back to 1996 [19]. Regarding the classification according to primary, it should be mentioned that
there was a substantial number of patients with “other” NEN subtypes. Here, a more
precise subanalysis was not possible, because this group was also very heterogeneous
with many different primaries (kidney, adrenal gland, paraganglion, CUP, jugulotympanic
paraganglion of the middle ear, etc.).
Additionally, in some cases several forms of therapy (c-TACE, MWA, LITT) were performed
on the same patient, making a separate assessment of the individual therapeutic successes
difficult.
In conclusion: The number of liver lesions and therapeutic intention were shown to
be prognostic factors for survival. It was shown that palliative patients could still
be treated curatively and vice versa. A high rate of complete ablation in thermoablative
procedures was achieved. LITT compared to MWA was associated with more complications.
An interesting new aspect shown by this study was the fact that c-TACE is especially
effective at the beginning of multiple interventions regarding NELM volume reduction.
Also, longer treatment breaks should be avoided. The evaluation of the course of multiple
c-TACE interventions has still been studied very little and therefore represents an
interesting prospect for the future.
Clinical relevance of the study
-
With increasing incidences of neuroendocrine neoplasms and insufficient scientific
data, further analysis of neuroendocrine neoplasms is essential.
-
For better prognostic assessment, identification of risk factors is important. In
this study, the number of liver lesions and the therapeutic intention were confirmed
as risk factors.
-
It has been shown that the effectiveness of c-TACE therapy decreases over the course
of several c-TACE interventions, thus providing an important finding for further evaluation
of c-TACE therapy.
