Keywords
Autologous - Hodgkin - refractory - relapsed
Introduction
Hodgkin lymphoma (HL) is a type of malignancy with high cure rates. However, about
15% of patients with early-stage disease and about 20%–30% with advanced-stage disease
either have refractory disease or tend to have relapse of the disease after initial
therapy.[1] Approximately 80% of patients have symptoms or signs of the disease at relapse.[2] The goal of the treatment in relapsed/refractory HL is long-term disease control
while minimizing the toxicity and complications of therapy. High-dose chemotherapy
followed by autologous stem cell transplant (ASCT) is the treatment of choice for
relapsed/refractory disease.[3]
[4] Although ASCT has not shown to improve the overall survival, it is considered the
standard of care.
Methods
This was a retrospective study conducted from January 2010 to July 2018 in the department
of hematology at our 200-bedded tertiary cancer hospital. The study was initiated
using computer-based database and medical records as the data source. Relapsed/refractory
HL cases were defined as clinically symptomatic or progressive or PET-CT scan relapsed/progressive
patients with or without proven histopathology. Relapse case was defined as a case
that came back after the remission from first-line chemotherapy. The refractory case
was defined as a case that progressed during the treatment with first-line chemotherapy.
A study pro forma was established, which included patient identification, diagnosis,
staging, histological types, international prognostic index score, chemotherapy types
and number of cycles, date of relapse, conditioning regimen, and date of transplant.
Patient’s disease status till the last follow-up was recorded along with the date
of relapse and/or death. After the collection of reports, statistical analysis was
conducted using SPSS Software version 20. The primary objective of our study was to
calculate the overall survival post autologous transplant, while the secondary objectives
were to calculate the overall response and disease-free survival in our patients.
Survival curves were plotted with Kaplan–Meier methodology. Patients who were lost
to follow-up after therapy were censored as alive at their last follow-up. Descriptive
statistics was used for the analysis of demographic variables, disease characteristics,
and response rates.
Results
Patients characteristics
A total of 22 patients were diagnosed with relapsed/refractory HL during the study
period. In our study, majority of the cases were male patients (59%) with a mean age
of 29 years (range 15–57 years) and were Stage 4A (40.9%), with nodular sclerosis
(54.5%) and International Prognostic Score (IPS) score of two (40.9%). B symptoms
at diagnosis were recorded in 45% of the patients. None of the patients were diagnosed
with tuberculosis prior to the histological diagnosis of HL – one of the differential
diagnoses in these patients. Nine percent of the patients had comorbidities. All (100%)
of the patients had the Eastern Cooperative Oncology Group performance status (ECOG-PS)
of ≤2. None of the patients had acquired immunodeficiency syndrome at the time of
diagnosis, and no patients had a history of exposure to radiation before the diagnosis
[Table 1].
Table 1
Clinical characteristics of patients
|
Patients characteristics
|
n (%)
|
|
TB – Tuberculosis; ECOG – Eastern Cooperative Oncology Group
|
|
Mean age
|
29.6±12
|
|
Male
|
13 (59.1)
|
|
Female
|
9 (40.9)
|
|
Age group
|
|
|
15–30
|
16 (73)
|
|
30–45
|
3 (13.5)
|
|
45–60
|
3 (13.5)
|
|
>60
|
0
|
|
National patients
|
17 (77.5)
|
|
International patients
|
5 (22.5)
|
|
Professional
|
11 (50)
|
|
Students
|
7 (32)
|
|
Homemaker
|
4 (18)
|
|
Comorbidity
|
2 (9)
|
|
TB
|
0
|
|
Retropositivity
|
0
|
|
Radiation exposure before
|
0
|
|
ECOG 1
|
22 (100)
|
Lymphoma characteristics
Stage 4A was the most common presentation with 40.9%. The most common histopathology
was nodular sclerosis observed in 54.5%, followed by mixed cellularity, lymphocyte-predominant
type, and lymphocyte-depleted type, in 36.5%, 4.5%, and 4.5%, respectively. IPS could
be estimated in all the patients. IPS score ≤4 was observed in 95.5% (21/22) of the
patients. No bone marrow involvement and extranodal sites of disease was observed.
Bulky disease (defined as largest tumor size ≥10 cm) was also not observed in our
patients. There were 9 relapsed cases and 13 refractory cases in total [Table 2].
Table 2
Clinical characteristics of lymphoma
|
Lymphoma characteristics
|
n (%)
|
|
HL – Hodgkin lymphoma; IPS – International prognostic score
|
|
Staging
|
|
|
IA
|
1 (4.5)
|
|
IB
|
1 (4.5)
|
|
IIB
|
3 (13.6)
|
|
IIIA
|
2 (9.1)
|
|
IIIB
|
3 (13.6)
|
|
IVA
|
9 (40.9)
|
|
IVB
|
3 (13.6)
|
|
Histological types
|
|
|
Lymphocyte depleted
|
1 (4.5)
|
|
Mixed cellularity
|
8 (36.5)
|
|
Nodular lymphocyte predominent HL
|
1 (4.5)
|
|
Nodular sclerosis
|
12 (54.5)
|
|
IPS score
|
|
|
1
|
8 (36.4)
|
|
2
|
9 (40.9)
|
|
3
|
4 (18.2)
|
|
4
|
0
|
|
5
|
1 (4.5)
|
|
B symptoms
|
10 (45)
|
|
Relapsed cases
|
9 (41.5)
|
|
Refractory cases
|
13 (58.5)
|
Treatment characteristics
Most of the patients (n = 21 patients, 95.5%) were treated with standard ABVD chemoregimen before the relapse,
while 4.5% of the patients received CHOP regimen due to advanced age or comorbidities.
Six cycles of chemotherapy were completed by all of the patients. Radiation was given
to 22.5% of the patients for either bulky sites or residual disease at the end of
chemotherapy. Post relapsed/refractory, the most common second-line regimen used was
ifosfamide, carboplatin, and etoposide (ICE) regimen (55%), followed by dexamethasone,
high-dose Ara-C, and Cisplatin (DHAP); gemcitabine, dexamethasone, and cisplatin;
and mesna, ifosfamide, mitoxantrone, and etoposide regimens. Majority of the patients
after the second-line chemotherapy had partial response (PR) (73%) before undergoing
autologous transplantation. Post autologous transplant, four patients had relapsed,
of which two patients received the third-line six cycles of Gemox chemotherapy, while
one patient received radiation to the relapsed mediastinum. About 40.5% of the patients
developed an infection during the transplant, which was salvageable with broad-spectrum
antibiotics. Transplant-related mortality was zero during our transplantation [Table 3].
Table 3
Treatment characteristics
|
Treatment charactersitics
|
n (%)
|
|
ICE – Ifosfamide, carboplatin, and etoposide; DHAP – Dexamethasone, high-dose Ara-C,
and cisplatin; CR – Complete response; PR – Partial response; SD – Stable disease;
PD – Progressive disease; ABVD – Adriamycin, bleomycin, vinblastine, dacarbazine;
CHOP – Cyclophosphamide, doxorubicin,oncovin, prednisone; GEMOX – Gemcitabine, oxaliplatin;
MINE – Mesna, ifosfamide, mitoxantrone, and etoposide
|
|
1st line chemotherapy
|
|
|
ABVD regimen
|
21 (95.5)
|
|
CHOP regimen
|
1 (4.5)
|
|
Second-line chemotherapy (salvage)
|
|
|
ICE regimen
|
12 (55)
|
|
DHAP regimen
|
6 (27)
|
|
GDP regimen
|
2 (9.0)
|
|
MINE regimen
|
1 (4.5)
|
|
ABVD regimen rechallenge
|
1 (4.5)
|
|
Response after salvage chemo
|
|
|
CR
|
2 (9)
|
|
PR
|
16 (73)
|
|
SD
|
1 (4.5)
|
|
PD
|
3 (13.5)
|
|
Third-line chemo posttransplant
|
2 (9)
|
|
GEMOX regimen
|
|
|
Radiation before transplant
|
5 (22.5)
|
|
Radiation after transplant
|
1 (4.5)
|
Transplantation characteristics
All the relapsed/refractory patients underwent autologous transplantation at our center.
The conditioning regimen used was BEAM regimen (100%) to treat patients for autologous
transplantation. The mean stem cell collection during the stem cell transplantation
was 6.022 ± 3.4 × 10 × 6/kg and the mean neutrophil engraftment duration was 13.3
± 3.8 days. The overall response rate was 81.8% with 9.1% complete response (CR),
72.7% PR, and 4.5% stable disease. The overall survival was 77.92 ± 6.65 months and
disease-free survival was 69.66 ± 8.13 months as shown in [Figures 1] and [2], respectively. There were two deaths (9.0%) during the follow-up period, one with
the relapse and other with acute myeloid leukemia transformation. A total of four
re-relapses occurred after autologous transplantation, and six (27%) patients were
lost to follow-up [Table 4].
Figure 1: Overall survival postautologous transplantation
Figure 2: Disease free survival post autologous transplantation
Table 4
Transplantation characteristics
|
Transplant characterictics
|
n (%)
|
|
TRM – Transplant related mortality; CR – Complete response; PR – Partial response;
SD – Stable disease; PD – Progressive disease; BEAM – BCNU, etoposide, cytrabine,
melphalan
|
|
Autologous transplant cases
|
22 (100)
|
|
Conditioning regimen BEAM
|
22 (100)
|
|
Mean stem cells collected (×106/kg)
|
6.022±3.4
|
|
Mean engraftment day
|
13.3±3.8
|
|
Infections during transplant
|
9 (40.5)
|
|
Response rate
|
|
|
Overall response rate
|
81.8%
|
|
CR
|
2 (9.1)
|
|
PR
|
16 (72.7)
|
|
SD
|
1 (4.5)
|
|
PD
|
3 (13.7)
|
|
Overall death
|
2 (9.0)
|
|
Transplant related death (TRM)
|
0
|
|
Death due to AML transformation
|
1 (4.5)
|
|
Death due to relapse
|
1 (4.5)
|
|
Relapse/refractory cases
|
4 (18)
|
|
Overall survival (months)
|
77.92±6.65
|
|
Disease free survival (months)
|
69.66±8.13
|
|
Lost to follow-up cases
|
6 (27)
|
Discussion
This report comprises about 96-month follow-up of a single institution cohort of patients
with refractory/relapsed HL who underwent ASCT. The results showed that high-dose
chemotherapy followed by ASCT can induce disease control and improve the prognosis
of patients with advanced refractory or relapsed HL. The patient population of this
study was heterogeneous and pretreated, with a median of two lines of chemotherapy
regimens before transplantation. Despite this, 91% of the patients were alive and
86.5% disease-free at the end of the follow-up.
The diagnosis of relapsed or refractory HL is mostly done clinically as most patients
are symptomatic at presentation. Occasionally, however, new lesions or lesions at
the initial site are picked up on imaging studies. NCCN v1.2017 recommends obtaining
contrast computed tomography (CT) scan of the neck, thorax, abdomen, and pelvis at
6, 12, and 24 months after completion of the therapy or as clinically indicated. The
role of positron-emission tomography (PET)-CT scan in the diagnosis of relapsed or
refractory disease is still not clearly defined. NCCN v1.2017 recommends PET-CT only
if the last PET was Deauville 4–5 to confirm CR. Although these imaging modalities
expose the patient to various risks, the benefits over clinical detection are not
very clear.[5]
[6] Repeat biopsies of the persistent or new lesions are recommended. Repeat biopsies
are especially useful in patients with refractory disease and late relapses (3–5 years
after primary treatment) or treating physician suspects another malignancy. In our
study, clinical examination and PET-CT scan with or without biopsy had been used to
confirm the relapsed/refractory cases.
Several prognostic factors have been evaluated by various investigators to predict
survival in relapsed/refractory disease.[7]
[8]
[9]
[10]
[11]
[12] These include patient-related factors such as poor PS, age >50 years, the presence
of B symptoms, poor response to the first chemotherapy, low albumin, anemia, and lymphocytopenia.
Disease-related factors include Stage III/IV at presentation, extranodal disease,
relapse in the previous radiation field, residual disease pretransplant, and time
to relapse <1 year. In our study, advanced stage had been found to be associated more
with relapsed/refractory cases, while IPS score was not found to be associated.
Several studies have emphasized the need for cytoreduction prior to transplant. Hence,
various salvage chemotherapy regimens have been studied in randomized controlled trials.[9]
[13]
[14]
[15]
[16]
[17]
[18]
[19]
[20]
[21]
[22] However, there is no gold standard salvage chemotherapy, as head-to-head comparison
among these various regimens has not been conducted. Several regimens such as gemcitabine,
vinorelbine, and pegylated liposomal doxorubicin; ifosfamide, gemcitabine, and vinorelbine;
and gemcitabine, carboplatin, and dexamethasone have also been tried with good results.[23]
[24]
[25] However, these regimens have not been tried in randomized controlled trials. The
decision to use the appropriate regimen is usually made by the treating physician
according to the institutional experience and protocols and individual patient-related
factors. One of the major factors which decide on the choice of salvage chemotherapy
regimens is the impact on subsequent peripheral blood stem cell (PBSC) mobilization.
Regimens containing melphalan have been reported to impair PBSC mobilization.[26]
[27] Hence, regimens which do not contain melphalan like ICE and DHAP have become popular
in recent years. One study concluded that although both ICE regimen and DHAP regimens
were safe, the former had slightly more response rates.[28] Bendamustine, lenalidomide, and everolimus have also been tried in several Phase
2 trials. We have used ICE regimen in majority of cases and we have found the maximum
benefits with minimum side effects.
Newer class of agents have also been used in Phase 2 trials. Notable among these are
the antibody–drug conjugates and programmed death receptor-1 (PD-1) inhibitors (immunotherapy).
Brentuximab vedotin (anti-CD30 antibody–drug conjugate) was initially used as single
agent. Recently, there has been an attempt to combine this agent with conventional
salvage chemotherapy regimens with good success rates.[29]
[30]
[31]
[32]
[33]
[34]
[35] Nivolumab (PD-1 inhibitor) has also been used recently. A Phase 1/2 trial demonstrated
good efficacy and safety when combined with brentuximab.[36] Further larger Phase 3 studies are required to validate the results of these preliminary
studies involving newer agents. BEAM regimen is most commonly used as high-dose conditioning
chemotherapy before ASCT. A trial by GHSG reported higher freedom from treatment failure
in patients who underwent ASCT following HDC compared to HDC alone. The overall survival
however remained the same.[37] Hence, NCCN v12017 recommends HDC followed by ASCT for all patients with relapsed/refractory
HL.
Survival after relapse post-ASCT remains poor. It is estimated that up to 50% of patients
ultimately relapse following ASCT. Treatment of such patients is particularly challenging.
RIC allogenic SCT remains one of the options but is limited by various factors such
as donor availability, patient preference, and lack of sensitivity of the disease
to chemotherapy. In our study, a total of four cases relapsed and one patient developed
acute myeloid leukemia post autologous transplantation. Of four patients, one died,
two received third-line GEMOX chemotherapy, and fourth received radiation to the mediastinum.
Later, three patients were doing well till the last follow-up.
Brentuximab vedotin has been successfully used in such patients. The 5-year survival
rates are encouraging considering the heavily pretreated nature of these individuals.
It can be used even if treated previously in the same patient.[38]
[39]
[40] Nivolumab and pembrolizumab have also been used in relapse post-ASCT with good results.[41]
[42]
[43] Very recently, a combination of immunotherapy and brentuximab was administered in
a small group of patients who had relapsed post-ASCT. The overall response rates were
100%. No serious Grade 3/4 toxicities which would lead to treatment discontinuation
were observed.[44] Lenalidomide alone or in combination with bendamustine has been tried. Other agents
which have given mixed results are histone deacetylase inhibitors such as panobinostat
and mTOR inhibitor everolimus.[45]
[46]
[47] However, we did not use any of these newer treatments in our re-relapsed cases.
The strength of this study lies in the fact that this is one of the considerable number
of patients’ data from India on relapsed/refractory HL treated with autologous transplantation.
However, this is a retrospective analysis which has its inherent flaws of missing
data and lack of follow-up.
Conclusion
ASCT plays an integral role in the treatment of patients with HL. Most patients with
HL are cured with combination chemotherapy with or without radiation therapy. ASCT
is currently the optimal treatment for patients who fail chemotherapy and radiation
therapy. Treatment of relapsed HL post autologous transplantation is particularly
challenging.
Consent
Informed consent was obtained from all patients for being included in the study.
