Participants characteristics and treatment pattern of relapsed/refractory mantel cell lymphoma [rrMCL]) participants treated by Bortezomib (BTZ) will be observed for cohort 1.

Participants characteristics and treatment pattern of newly diagnosed MCL participants (if more than 20% of total BTZ-treated MCL) will be analysed for cohort 2.

Continuous variable (age) will be summarized using descriptive statistics.

Categorical variable (disease status) will be summarized using a frequency distribution with the number and percentage of participants in each category. Treatment response will be analyzed by this variable if newly diagnosed MCL patients account for more than 20 percent (%) of total.

A worsening in Eastern Cooperative Oncology Group (ECOG) performance status score was defined as greater than or equal to 1-point increase from Baseline. ECOG is a 5-point scale 0=Fully active, 1=Ambulatory, carry out work of sedentary nature, 2=Ambulatory, capable of all self-care, 3=Capable of limited self-care, confined to bed or chair more than 50% of waking hours, 4=Completely disabled, no self-care, totally confined to bed or chair, 5=Dead.

Ann Arbor stage can be obtained from imaging results or directly from admission records. Ann Arbor stage describes areas of involvement; Stage I(IE) - One lymph node region or extralymphatic site (IE); Stage II(IIE)- Two or more lymph node regions or at least one lymph node region plus a single localized extralymphatic site (IIE) on the same side of the diaphragm; stage III (IIIE, IIIS)-Lymph node regions or lymphoid structures (example, thymus,Waldeyer's ring) on both sides of the diaphragm with optional localised extranodal site (IIIE) or spleen (IIIS); stage IV-Diffuse or disseminated extralymphatic organ involvement.

ORR is defined as the sum of complete response [CR] rate (CR+ unconfirmed complete remission [CRu]) + Partial remission [PR] rate as per International Working Group (IWG 2007) criteria. These response criteria are based on the reduction in the size of the enlarged lymph node as measured by computerized tomography (CT) scan and the extent of bone marrow involvement that is determined by bone marrow aspirate and biopsy. Complete response [CR] defined as disappearance of all evidence of disease; CRu satisfies CR criteria, however any residual lymph node mass greater than (>)1.5 centimeter (cm) in longest transverse dimension or extranodal site of disease (irrespective of size) must have regressed by more than 75% of the product of the longest perpendicular dimensions compared to the pretreatment baseline. PR defined as at least a 50% decrease in sum of the product of the diameters (SPD) of up to six of the largest dominant nodes or nodal masses.