1. Introduction
Hodgkin lymphoma (HL) is a lymphoid tissue neoplasm. The damaged tissue comprises mono- and multinucleated cells surrounded by non-neoplastic inflammatory cells. Two histopathological subtypes are recognized: Classic and Nodular Lymphocytic Predominance [1] occurring in individuals of all ages; however, there are two peaks of occurrence (adolescents and over 60 years of age) and a slight predominance in men. HL accounts for about 10% of all lymphomas and 0.5% of all cancers in the United States of America [2]. The incidence has remained unchanged in recent decades. In 2020, there were 83,087 new cases registered worldwide per year, out of which 7091 cases corresponded to South America [3].
The overall incidence, age of occurrence, and even survival vary in different geographic areas [4,5,6], and the incidence of subtypes is affected by geography and socioeconomic factors [5]. Although the specific causes of these discrepancies are unknown, describing HL's epidemiological characteristics helps to clarify this behavior. Reports from Latin America have shown a lower incidence at an earlier age of onset and lower survival compared to Caucasian populations [4,7,8]. In Ecuador, the clinicopathological characteristics of adult HL were described in 2007; and are contrasted the epidemiological data of this study are compared with data from the last 11 years [6,9,10].
This study provides the epidemiological characteristics of patients diagnosed with HL treated at a national referral cancer center from 2010 to 2021. In addition, we describe the local incidence, trends over time, age characteristics, place of origin, and distribution based on histopathological subtypes to help clarify geographical differences and determine a baseline for future research.
2. Material and methods
A cross-sectional descriptive observational design study was carried out at the SOLCA (Sociedad de Lucha Contra el Cancer), Guayaquil. This is a private non-profit oncology institution for public benefit. It has comprehensive and partial agreements for the provision of services with different institutions of the Ecuadorian Network of Comprehensive Health Care (RPIS) and has been established as a reference center at the national level.
The study included patients of all ages with a diagnosis of HL, who were treated between 2010 and 2021, constituting the total population. Data were obtained from the institution’s hospital tumor registry, identified by the ICD 10 coding: C81 (HL). Patients who lacked the necessary epidemiological information were excluded.
The demographic variables were sex, age at diagnosis, histopathological subtype, and province of origin. For data analysis, Microsoft Office 2010 Excel spreadsheets, SPSS v.29 license were used. Descriptive statistics were used to summarize the study variables, reported in frequencies and percentages. Continuous variables such as age are reported with medians and ranges. A trend analysis was performed to assess the annual percentage, and the most common types of neoplasms in both sexes in 2021 were identified to determine the incidence of HL.
Regarding ethical aspects, the study was carried out with open data and was authorized by the research committee of SOLCA Guayaquil.
3. Results
Of the different types of neoplasms treated at the SOLCA Hospital in 2021, HL is in 16th place in frequency, corresponding to 1.67% of the total cases (Fig. 1).
We obtained 870 patients with ICD 10 C81 from the hospital registry; 646 patients with a diagnosis of HL, treated between 2010 and 2021, were included in the study. We excluded cases whose complete data were not available (Fig. 2).
Table 1 shows the epidemiological characteristics of the patients treated for Hodgkin lymphoma according to histological subtype, sex, age of occurrence, and the three central provinces of origin (see complete map in Fig. 3).
Table 1
Clinical and demographic characteristics of patients with Hodgkin lymphoma treated at SOLCA - Guayaquil hospital.
Figure 4 illustrates the trend in the care of HL patients at the SOLCA - Guayaquil hospital during the study period, distinguishing between patients who received partial care through any service, and those who received specific oncological treatment at the institution.
Figure 4
Trend of patients treated for Hodgkin lymphoma at the SOLCA - Guayaquil hospital, 2010 - 2021
The median age of disease occurrence was 26 years, with a greater number of patients diagnosed in adulthood. Within the epidemiological characteristics of age group and sex in patients with Hodgkin lymphoma, the highest proportion was observed in men in the group of 0-19 years, with 37.7%; while in women it was the group from 20-29 years, with 45.5% (Fig. 5).
4. Discussion
In this study, the proportion of Hodgkin lymphoma in 2021 and its behavior between 2010 and 2021 were obtained. It should be noted that the SOLCA - Guayaquil Hospital is a reference institution for cancer patients and provides services to the public and private health network. The most frequent province of origin was Guayas, with approximately three out of every five patients. A percentage increase in care has been observed annually since 2010 with 4.0%, 2016 with 9.8%, and 2021 with 12.7%. The highest proportion was recorded in 2019 with 14.6%. This may be due to greater health coverage and better public policies.
Furthermore, Hodgkin lymphoma with nodular sclerosis was the most frequent with 50.3%. This figure is maintained over time in the institution as shown by the 10-year study carried out from 1998 to 2007, which reports a frequency of 51.4% for this histological subtype [11]. Likewise, at the Comandante Pinares hospital in the period 2007-2017, nodular sclerosis subtype was the most frequent with 35.3% of cases mostly in men [12]. Also, this research aligns with the findings of the Institute of Hematology and Immunology of Cuba, which found that Hodgkin lymphoma with nodular sclerosis was the most common type of lymphoma in men, representing 64% of cases [9]. Similarly, the AD study in the State of Pará, Brazil, showed that nodular sclerosis was the most common type in men 64% [13]. In the same way, the HL study in western Paraná, Brazil, showed that the nodular sclerosis type was the most frequent in men (64.6%) [14].
In addition, the higher proportion observed in men in the 0-19 years age group is very similar to that of the HL study in western Paraná, Brazil, which indicated they were mostly men (52%) older than 10 years (75%) with a diagnosis of nodular sclerosis (48%) [15].
5. Conclusions
Hodgkin lymphoma with nodular sclerosis is the most common type Hodgkin lymphoma in patients treated at the SOLCA - Guayaquil hospital during this study period, particularly in men from 0 to 19 years of age and women from 20 to 39 years of age. This situation is similar to the world literature on the behavior pattern of this disease.
6. Limitations
While this study could not explain the incidence of Hodgkin lymphoma in Guayaquil, it provided valuable information on the distribution by age, sex, and other aspects of the disease. The results open the door to further research to better understand the incidence of Hodgkin lymphoma in the city and to develop more effective prevention and control strategies.