Myeloproliferative disorders (MPDs) are a diverse group of conditions that are characterised by the overproduction of red cells, white cells and/or platelets in bone marrow. There are numerous conditions considered in this group but the most common are:
Neurolymphomatosis is a rare condition characterised by the direct invasion of the cranial and peripheral nerves and roots by lymphoma, in the great majority B-cell non-Hodgkin lymphoma.
It should be differentiated from non-tumour conditions associated with lymphoma that also affect the periphe...
Nodular lymphoid hyperplasia (NLH) is a type of rare, benign, lymphoproliferative disease. It is most commonly reported affecting the gastrointestinal and respiratory systems.
The presence of gut/mucosa associated lymphoid tissue (GALT/MALT) can be seen in children and young adults as a normal ...
Non-Hodgkin lymphoma (NHL) is a catch-all term for lymphomas that are not of the Hodgkin subtype. It is a heterogeneous group of malignancies in terms of histology, clinical presentation, and prognosis.
See 2008 WHO classification for further information on subtypes.
There are several non lymphomatous lymphoid disorders that can affect the lung. This implies that they comprise of lymphoid tissue but may not have progressed as far as an overt lymphoma. They include:
lymphocytic interstitial pneumonia
This article lists examples of normal imaging of the gastrointestinal tract and surrounding structures, divided by modality.
example 1: abdominal film
example 2: erect and supine
example 3, example 4: paediatric
example 5: young adult male
example 1, exampl...
This article lists examples of normal imaging of the liver and biliary tree and surrounding structures, divided by region and modality.
liver silhouette: example
example 1 with shear wave elastography
liver Doppler ultrasound: example ne...
Pancreatic lymphoma is most commonly a B-cell sub-type of non-Hodgkin lymphoma.
Typically seen in middle-aged patients: mean of 55 years; range, 35-75 years and in immunocompromised patients.
Presentation is often non-specific. reported symptoms include 1:
Paraneoplastic syndromes occur secondary to the indirect effects of a malignancy and occur remotely to the primary malignancy. Symptoms are mediated by cytokines, hormones or immune cross-reactivity. These syndromes can cause a diverse range of symptoms and can affect multiple systems.
Perisplenitis is acute inflammation of the splenic capsule and its peritoneal covering.
It is seen uncommonly but there is no data on its actual incidence.
It is seen usually in young and middle-aged patients, with acute left hypochondrial or lower chest pa...
PET-CT is a combination of cross-sectional anatomic information provided by CT and the metabolic information provided by positron emission tomography (PET).
PET is most commonly performed with 2-[F-18]fluoro-2-deoxy-D-glucose (FDG). Fluorine-18 (F-18) is an unstable radioisotope and has a half-...
Pituitary lymphoma is very rare, although lymphomatous (or leukaemic) infiltration of the perisellar dura is not infrequently encountered as part of more widespread CNS disease. This article concerns itself with involvement of the pituitary itself rather than the region more broadly. For a gener...
Plasmacytomas are a discrete, solitary mass of neoplastic monoclonal plasma cells in either bone or soft tissue (extramedullary). It is a rare tumour that is associated with latent systemic disease in the majority of affected patients. It can be considered as a singular counterpart of multiple m...
Pleural involvement with lymphoma can occur in two situations:
primary pleural lymphoma
primary effusion lymphoma
secondary involvement of the pleura with lymphoma
POEMS syndrome is an acronym for a rare multisystem disorder comprising of a minimum of three of the following features in the setting of a plasma cell dyscrasia:
M: monoclonal gammopathy
S: skin changes (including hyperpigmentation and sk...
Polycythaemia vera (older term: polycythaemia rubra vera) is a myeloproliferative disorder that results in an excess of red blood cells in the bloodstream.
The estimated prevalence is around 2-3 per 10,000 people. It typically presents in older individuals. There may be a slightly...
Polyglandular autoimmune syndromes (PAS) are a rare set of diseases characterised by the presence of ≥2 autoimmune endocrine disease.
Three types of PAS have been described.
PAS type I
a.k.a. APECED (autoimmune polyendocrinopathy, candidiasis and ectodermal dystrophy) or MEDAC (mu...
Primary bone (skeletal/osseous) lymphoma (PBL) is a less common manifestation of lymphoma than secondary involvement from disseminated lymphoma. It is rare, accounting for <5% of bone tumours and <1% of non-Hodgkin lymphoma.
PBL is defined as the presence of lymphoma isolated to on...
Primary effusion lymphoma is a rare form of non-Hodgkin lymphoma (diffuse large cell B cell lymphoma) characterised by malignant fluid accumulation in the absence of lymphadenopathy.
Typical sites of accumulation include
Primary hepatic lymphoma (PHL) is rare accounting for roughly 100 described cases. If it is being considered as a diagnosis, distal lymphadenopathy, splenomegaly, bone marrow disease, and leukaemia should not be present for at least 6 months after the liver tumour is detected (see: secondary hep...
Primary immunodeficiency states are heterogenous group of disorders that occur when there is an impairment of humoral or cell-mediated immunity in the absence of any recognised precipitating cause such as drug therapy or infective agent such as human immunodeficiency virus (HIV).
Primary mediastinal large B-cell lymphoma is a distinct entity, recognised in the WHO classification of lymphoma.
Primary mediastinal large B-cell lymphoma accounts approximately 5% of large B-cell lymphoma, which is usually disseminated or found in the abdomen. There appears to b...
Primary ovarian lymphoma (POL) refers to involvement of the ovary with lymphoma but without involvement of any other site. It is an extremely rare yet well recognised condition.
POL accounts for ~1.5% of ovarian tumours 5.
The rarity of this condition is probably contr...
Primary pleural lymphoma is extremely rare, especially in immunocompetent patients.
Primary pleural lymphoma accounts for <0.5% of all non-Hodgkin lymphoma 2 and ~2.5% of primary chest wall tumours 4.
Primary pleural lymphoma may be Hodgkin or non-Hodgkin lymphoma wit...
Primary pulmonary lymphoma (PPL) refers to a clonal lymphoid proliferation affecting the lungs without any detectable extrapulmonary involvement. It is a much rarer type of pulmonary lymphoma and is most frequently represented by lymphoma of B cell lineage - often marginal zone B-cell lymphoma o...
Protein C deficiency is a hypercoagulable state due to reduced activity or an absolute deficiency of protein C, an anticoagulant protein. Protein C deficiency increases the risk of venous thrombosis.
The prevalence of protein C deficiency in the general population is around 1 per ...
Protein S deficiency is a hyperocoagulable state associated with increased risk of venous thrombosis (up to 5% of patients with deep venous thrombosis may carry this deficiency).
Protein S deficiency may be expected in ≈1 of every 500 people 3.
Protein S, a vitamin K-d...
Pulmonary leukostasis is a medical emergency that is most commonly seen as a complication of chronic myeloid leukaemia (CML) in blast crisis, and acute myeloid leukemia when white blood cell (WBC) counts are over 100 x 109/L (100,000/microL). It needs to be considered in any patient with myeloge...
Pulmonary lymphoma refers to lung parenchymal involvement with lymphoma.
It can be broadly divided as primary or secondary.
primary pulmonary lymphoma: (rare) usually non-Hodgkin lymphoma which is limited to the lung with or without mediastinal lymph node involvement and with no evi...
The Rai staging system is one of the two staging systems currently adopted in assessment of chronic lymphocytic leukaemia (CLL).
It comprises of stages 0 to IV and classifies chronic lymphocytic leukemia into low, intermediate and high-risk categories, which correspond with stages 0, I & II, an...
A number of sonographic features are helpful in distinguishing reactive versus malignant lymph nodes.
Grey scale features
Features that favour reactive/infective nodes over malignancy include:
surrounding soft tissue oedema
Doppler examination is particularly...
Reed-Sternberg cells are a classical finding diagnostic of Hodgkin lymphoma. They are giant, multinucleated cells with abundant pale cytoplasm. Reed-Sternberg cells are rare, making up <1% of lymphoid tissue, with the background comprised of lymphocytes, plasma cells, eosinophils and macrophages.
Renal lymphoma is usually seen as a part of spectrum of multi-systemic lymphoma, however, rarely may be seen as a primary disease.
While renal lymphoma has autopsy incidence of 30-60% in lymphoma patients, actual CT diagnosis incidence is ~ 5%1.
The kidneys are the most common ab...
The reticuloendothelial system (RES) comprises of a number of tissues:
liver Kupffer cells
Retrorenal spleen refers to variant position of the spleen, when its inferior portion lies posterior to the upper pole of the left kidney.
This normal variant occurs in ~20% of patients, with the finding more common in patients who lie supine 1.
Recognition of this variant is important to avoi...
Richter transformation is defined as development of high-grade non-Hodgkin lymphoma (NHL) in patients with chronic lymphocytic leukaemia (CLL) or small lymphocytic lymphoma.
It has been expanded to include other lymphoid malignancies that develop in CLL patients, including Hodgkin disease, prol...
Rosai-Dorfman disease, also known as sinus histiocytosis with massive lymphadenopathy, is a rare benign idiopathic proliferative disease that involves phagocytic histiocytes.
The disease predominantly occurs in young adults with a mean age at presentation of 21 years. There may be...
Rubinstein-Taybi syndrome (RTS) is a very rare genetic multi-system disorder primarily characterised by mental retardation, broad and often angulated thumbs and halluces, and distinctive facial features.
The estimated incidence is 1 in 100,000-125,000 live births 5.
Sclerosing angiomatoid nodular transformation (SANT) of the spleen is a recently recognised, rare, non-neoplastic vascular splenic lesion of uncertain aetiology.
The term SANT first appeared in the literature in a 2004 paper by Martel et al. which examined a series of 25 cases 3. ...
Secondary hepatic involvement with lymphoma (secondary hepatic lymphoma) is common, much more so than primary hepatic lymphoma.
Hepatomegaly with deranged liver function tests is the most common presentation. Jaundice is common. Rarely, patients may present with acute li...
Secondary involvement of the bone with lymphoma, also referred as secondary bone lymphoma, is much more common than primary bone lymphoma, occurring in ~15% of disseminated lymphomas.
Secondary bone lymphoma is defined as lymphoma involving the bone with nodal disease occurring wit...
Secondary involvement of the pleura with lymphoma (secondary pleural lymphoma) is very common, occurring in ~20% of lymphomas. It may be a result of an extension of lymphoma into the visceral or parietal pleura or be a complicating pleural effusion and is a poor prognostic factor.
Secondary pulmonary lymphoma (SPL) refers to pulmonary involvement with lymphoma when the condition is not limited to the lung and has mediastinal lymph node involvement or evidence of extrathoracic dissemination for at least three months after the initial diagnosis. This is a more common form o...
Sézary syndrome (SS) is a type of cutaneous T-cell lymphoma. It is sometimes considered an advanced and leukaemic form of cutaneous T-cell lymphoma (CTCL).
It is clinically characterised by an extensive erythematous rash covering most of the body as well as the presence o...
Sickle cell disease (SCD) is a hereditary (autosomal recessive) condition resulting in the formation of abnormal haemoglobin (a haemoglobinopathy), which manifests as multisystem ischaemia and infarction, as well as haemolytic anaemia.
There is no recognised gender predilection. ...
Abdominal manifestations of sickle cell disease (SCD) are wide and can involve many organs.
For a general discussion, please refer to sickle cell disease.
may occur transiently with the sequestration syndrome, where rapid pooling of blood occurs in the spleen, resulting ...
Small bowel lymphoma is the most common small bowel malignancy, accounting accounts for ~25% of all primary small bowel malignancies and ~40% of all primary gastrointestinal lymphomas.
Small bowel lymphoma is most commonly secondary extranodal involvement in widespread systemic ly...
Small lymphocytic lymphoma (SLL) is a non-Hodgkin lymphoma affecting the B-lymphocytes of the immune system. It is considered the same disease process as chronic lymphocytic leukaemia (CLL) although unlike CLL, the tumour cells are mostly confined to the lymph nodes rather than the blood stream...
Smouldering multiple myeloma (SMM) is a precursor to multiple myeloma.
Similar to MGUS patients, smoulder multiple myeloma patients are asymptomatic.
The criteria for smouldering multiple myeloma diagnosis according to the International Myeloma Worki...
The spleen is an organ of the haematological system and has a role in immune response, storage of red blood cells and haematopoiesis.
The spleen is a wedge-shaped organ lying mainly in the left upper quadrant (left hypochondrium and partly in the epigastrium) and is protected by ...
Splenic epithelial cysts, also referred as splenic epidermoid cysts or primary splenic cysts, are usually an innocuous incidental finding on imaging. They represent about 20% of the cysts found in the spleen. On imaging, they present as a unilocular fluid lesion with thin and smooth walls and no...
Splenic (artery) embolisation is an endovascular technique for treatment of splenic and splenic artery pathology as an alternative to splenic artery ligation or splenectomy. It often results in successfully treating the underlying pathology, while maintaining at least partial splenic function.
Splenic hamartomas are very rare lesions commonly found incidentally on imaging. They are most often solitary but may be present as multiple nodules in patients with tuberous sclerosis or Wiskott-Aldrich syndrome.
The recently-described sclerosing angiomatoid nodular transformatio...
Splenic metastases are relatively rare on imaging, although they are more commonly found on autopsy. Typically they are part of a widespread metastatic disease.
The rate of splenic metastases varies between 1-10% of autopsy studies, depending on whether microscopic or macroscopic ...
Splenic pseudocysts, also referred as secondary splenic cysts, are acquired cystic lesions not delineated by a true epithelial wall. They represent the majority of the splenic cystic lesions, corresponding to approximately 80% of them (c.f. splenic epithelial cysts). The main causes are:
Splenic trauma can occur after blunt or penetrating trauma or secondary to medical intervention (i.e. iatrogenic). The spleen is the most frequently injured organ after blunt trauma.
Patients may present with left upper quadrant/left chest pain, left shoulder tip pain (re...
Splenomegaly is a term which refers to enlargement of the spleen. The normal adult splenic length upper limit is usually around 12-15 cm. Also one should know how to calculate splenic index, volume and mass by CT and MR techniques. Massive splenomegaly is a term used when the spleen weighs >1000...
Splenunculi (also known as supernumerary, accessory spleens, or splenules) are small nodules of spleen that are separate from the rest of the organ. They are benign and asymptomatic, their importance is mainly related to the need to distinguish them from more sinister pathology.
Sweet syndrome (acute febrile neutrophilic dermatosis) is characterised by a constellation of clinical symptoms, physical features, and pathologic findings which include:
tender erythematous skin lesions (papules, nodules, and plaques)
a diffuse infiltrate consisting predo...
T cell prolymphocytic leukaemia (T-PLL) is a rare and unusual haematological malignancy.
It represents around 2% of all mature lymphocytic leukaemias in adults over the age of 30 1. It usually affects older adults with an average age at presentation being around 65 years. There ma...
Technetium agents based on the technetium-99m (Tc-99m) radioisotope are frequently used agents in medical imaging. The radioactive technetium radiotracer can be chelated to a number of different compounds to create specific radiopharmaceuticals and optimise the functional imaging of various stru...
Testicular leukaemia can be seen in patients during and after acute leukaemia. The blood-testis barrier limits chemotherapy from reaching the testicle, and therefore the testicle can act as a harbor for leukaemic cells.
Typically presents with painless testicular enlargem...
Testicular lymphoma is an uncommon cause of testicular malignancy. Lymphoma can involve the testes in three ways:
primary site of extranodal disease (primary testicular lymphoma)
secondary involvement of systemic disease
primary manifestation of subclinical systemic disease
This article is c...
Thalassaemia is an autosomal recessive haemoglobinopathy that originated in the Mediterranean region. The genetic defect causes a reduction in the rate of globin chain synthesis which causes the formation of abnormal haemoglobin molecules. The resultant microcytic anaemia is the characteristic p...
Thrombotic thrombocytopaenic purpura (TTP) is a rare but life-threatening condition characterised by thrombocytopaenia, microangiopathic haemolytic anaemia and end-organ damage.
The prevalence of TTP is ten cases per one million people 2. Ninety-percent of cases occur in adulthood...
In periods of bodily stress the thymus may acutely shrink to 40% of its original volume (depending on the severity and duration of the stress). During the recovery phase it can grow back to its original size or even larger (up to 50% larger). This "rebound effect" is known as thymic rebound hype...
Tower vertebrae a rare manifestation of sickle cell disease, in which short infarcted vertebrae are seen adjacent to other abnormally grown in height vertebrae.
codfish or h-shaped vertebrae
anterior vertebral vascular notches
Trousseau syndrome is referred to by a number of names, such as migratory thrombophlebitis and cancer-associated thromboembolism, but is essentially the association of venous thrombosis provoked by a yet to be diagnosed malignancy.
Tumours associated with increased erythropoetin are varied and numerous. Patients will be polycythaemic due to erythropoetin secretion. Tumours in this group include:
renal cell carcinoma (RCC) 2
hepatocellular carcinoma (HCC)
Twin anaemia polycythaemia sequence (TAPS) is considered a variant of the twin to twin transfusion syndrome (TTTS).
TAPS may occur spontaneously in up to 5% of monochorionic twins and may also develop after incomplete laser treatment in twin-to-twin transfusion syndrome cases 2.
Typhlitis, also called caecitis or neutropaenic colitis, is a necrotising inflammatory condition which typically involves the caecum and, sometimes, can extend into the ascending colon or terminal ileum.
Typhlitis was first described in children with leukaemia and severe neutropae...
Uterine lymphoma refers to involvement of the uterus with lymphoma. Some authors also place lymphoma of the uterine cervix under this group.
It is rare condition with initial uterine involvement occurring in only 1% of patients with lymphoma 3. However, uterine involvement is more...
Vaginal lymphoma can refer to:
secondary involvement of the vagina (secondary vaginal lymphoma) from widespread generalised lymphoma
usually comprises of diffuse large cell B non-Hodgkin's lymphoma (DLBCL) 2
primary vaginal lymphoma
Vanishing vertebrae is a rare ischaemic manifestation of sickle cell disease, in which a completely infarcted vertebral body literally disappears or vanishes, as a result of infarction. In the few reported cases, the posterior elements remain intact.
codfish or h-shaped vertebrae
Vitamin K is a family of fat-soluble vitamins essential for normal blood-clotting function and comprises two vitamers that are found naturally: phytomenadione (also known as phylloquinone or K1) and menaquinone (or K2).
Menaquinone is synthesised by normal flora in the intestine although the am...
Von Willebrand disease (vWD) is the most common inherited bleeding diathesis (easy bleeding).
Bruising and mucosal bleeding are typical presentations, but there is a spectrum of severity. The more residual vWF a patient has, the less severe the bleeding.
Waldenström macroglobulinaemia, previously also known as lymphoplasmacytic lymphoma, is a type of B-cell lymphoma. It is a rare condition, accounting for only 1% of all lymphoproliferative disorders.
Recent publications classify Waldenström macroglobulinaemia as an lymphoplasmacytic lymphoma w...
The Wells criteria for pulmonary embolism is a risk stratification score and clinical decision rule to estimate the probability for acute pulmonary embolism (PE) in patients in which history and examination suggests acute PE is a diagnostic possibility. It provides a pre-test probability which, ...
Wiskott-Aldrich syndrome (WAS) is a rare immunodeficiency disease with a characteristic phenotype that includes:
X-linked recessive and only occurs in boys
petechiae, bloody diarrhoea, epistaxis due to thrombocytopenia with small platelets
eczema starts in first month of life
Zebra spleen, also referred to as psychedelic spleen or more correctly inhomogeneous splenic enhancement refers to the transient heterogeneous parenchymal enhancement of the spleen during the arterial or early portal venous phases of contrast enhancement in CT, MRI, or ultrasound imaging.