Extramedullary haematopoiesis in patients with transfusion dependent β-thalassaemia (TDT): a systematic review

Figures & data

Figure 1. Prisma flowchart with details of the article screening process.

Table 1. Demographic characteristics of BTM patients with EMH.

Characteristics	Results (N = 253)
Gender
Males	144 (56.9%)
Females	103 (40.7%)
Not reported	6 (2.3%)
Mean age at presentation of EMH (years)	35.3 ± 0.5
Ethnicity (N, %)
Not reported	64 (25.6%)
Italian	167 (66%)
Iranian	7 (2.8%)
Greek, Chinese, African	2 (0.8%)
Pakistani, Palestinian, Emirati, Iraqi, Qatari, Liberian, Australian, Mediterranean, Cambodian	2 (0.8%)
	2 (0.8%)
	1 (0.4%)
Mean haemoglobin (mg/dL)	8.2 ± 2.1
Site of EMH (N, %)
Not reported	3 (1.2%)
Around the Spinal cord	222 (87.7%)
Skull	6 (2.4%)
Spinal cord	5 (1.9%)
Intracranial	4 (1.6%)
Thorax	3 (1.2%)
Spleen	1 (0.4%)
Liver	2 (0.8%)
Mediastinum	1 (0.4%)
Adrenal gland	6 (2.4%)
Diagnostic tests (N, %)
Not reported	4 (1.6%)
MRI	226 (89.3%)
CT Scan	25 (9.9%)
Biopsy	9 (3.6%)
PET scan	4 (1.6%)
SPECT	3 (1.2%)
Ultrasound	3 (1.2%)
Myelogram	1 (0.4%)
X-ray	1(0.1%)
Treatment (N, %)
Not available	174 (68.8%)
Blood transfusions to increase pre-transfusion Hb	30 (11.8%)
Exchange transfusion	2 (0.8%)
Hydroxyurea	12 (4.7%)
Steroids	6 (2.4%)
Radiotherapy	20 (7.9%)
Surgery	15 (5.9%)
Outcome
Not reported	201 (79.4%)
Recovered	52 (20.5%)

Figure 2. Frequency of reported presenting features of EMH in BTM patients.

Table 2. Treatment lines among the patients with a reported outcome.

Treatment	Count (N = 52)
In various combination
Blood transfusion	27 (51.9%)
Exchange transfusion	1 (1.9%)
Hydroxyurea	11 (21.1%)
Steroids	6 (11.5%)
Radiotherapy	19 (36.5%)
Surgery	12 (23%)
Exclusive treatment
Blood transfusion	6 (%)
Hydroxyurea	1 (%)
Steroids	1 (%)
Radiotherapy	5 (%)
Surgery	12 (%)

Figure 3. MRI spine: intraspinal epidural extramedullary masses T2 (lowered border) to T9 (arrows in A and B). Anterior displacement and compression of the cord in the thoracic spine is secondary to the compression by the EMH (arrow in C at T7 level) reaching upto the left neural foramen (arrow in D at T10 level). Note. Image taken from Clinical Case reports from a previously published article [18]. The licence of the article (CC-BY) permits unrestricted reuse of the published work.

Figure 4. MRI spine: (A) Sagittal T2 WI showing a diffuse low-signal intensity of the bone marrow of a well-defined isointense mass (5.3 × 3 cm) in the presacral region (blue arrow). A second mass (2 × 1 cm) in anterior extradural space posterior to S1 level (Blue arrow). (B) Mass enhancement seen in the axial postcontrast fat-saturated image at the presacral area (Blue arrow). (C) Axial postcontrast fat-saturated image at S1 level showing anterior extradural mass with slightly high signal intensity (blue arrow) at the midline, with displacement of the S1 nerve roots laterally. Note. Image taken from Clinical Case reports from a previously published article [42]. The licence of the article (CC-BY) permits unrestricted reuse of the published work.

Figure 5. (A) Haematoxylin and eosin-stained slide showing lymphoid tissue comprising tiny lymphocytes with scattered megakaryocytes (arrows), and clusters of myeloid and erythroid cells (circled). (B) Immunohistochemical stain “CD61” highlighting the cytoplasm of megakaryocyte in brown chromogen. (C) Immunohistochemical stain “MPO”, highlighting the myeloid precursors. (D) Immunohistochemical stain “Hemoglobin A”, highlighting the erythroid precursors. Note. Image taken from Clinical Case reports from a previously published article [42]. The licence of the article (CC-BY) permits unrestricted reuse of the published work.

Figure 6. The pathophysiology of EMH in BTM. Concept reused with permission from Yang et al. [22].

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