Contrary to solid cancers, hematologic malignancies (blood cancers) have some unique characteristics and often require different treatments. Importantly, it is now well established that the hematologic malignancies (lymphoma, leukemia, and myeloma) despite sharing some common clinical features are also biologically distinct entities. Among them, lymphoma, a cancer of lymphocytes, is a very heterogeneous group of neoplasms exhibiting diverse clinical presentations, prognoses, and therapeutic responses and includes more than 70 different subtypes. Lymphomas are conventionally divided into two main groups, Hodgkin’s lymphoma (HL) and non-Hodgkin’s lymphoma (NHL), with both types having multiple early clinical manifestations, often delaying the diagnosis. By comparison, HLs are rare and less heterogeneous, whereas NHLs are more a common and highly heterogeneous group of B-, T-, or NK-cell neoplasms. HL only accounts for approximately 10% of newly diagnosed lymphoma 
. The complex heterogeneity can also be evident from the fact that in HL alone, the distinctions can be made between two subtypes, classic HL (cHL) and rare nodular lymphocyte-predominant HL (nLPHL) 
. Besides, cHL is further categorized into nodular sclerosis (NS), mixed cellularity (MC), lymphocyte-rich (LR) and lymphocyte-depleted (LD) cHL. The cHL subtype is composed of Hodgkin (H) and Reed-Sternberg (RS) cells, collectively referred to as Hodgkin and Reed-Sternberg cells (HRS). The scenario is more complex in NHL, which is classified according to the type of lymphocytes involved: B lymphocytes (B-cells) or T lymphocytes (T-cells). Diffuse large B-cell lymphoma (DLBCL), follicular lymphoma (FL), and Burkitt’s lymphoma (BL) are common NHL types that are usually classified according to their aggressive or slow growing characteristics.
As per reports from the SEER database (https://seer.cancer.gov/
, accessed on 3 August 2021), HL affected approximately 219,128 people in the United States in 2018. To mention, HL is quite curable, but there are differences in incidence rates, sex and age distribution (young and adults), mainly based on the socioeconomic background 
. The most common age group of diagnosis is generally between 20 and 34 years old. Contrarily, NHL pose a challenge to the treatment response. According to the German Center for Cancer Registry Data (ZfKD), about 19,200 people in Germany were diagnosed with NHL in 2017, mostly in people of advanced age (average: women 72 years, men 70 years). In 2020, the number of incident cases is increased to 18,549 in Germany from the data of GLOBOCAN 2020 (http://gco.iarc.fr/today
, accessed on 25 November 2021). Similarly, approximately 81,560 patients are expected to be diagnosed with NHL in the United States in 2021 according to data from Cancer Statistics Center of American Cancer Society (http://cancerstatisticscenter.cancer.org/
, accessed on 3 August 2021).