Eble JN, Sauter G., Epstein JI, Sesterhenn IA - iarc

Haemangioma
P. Tamboli
Definition
Haemangioma is a benign vascular
tumour that occasionally arises in the
kidney.
ICD-O code 9120/0
Epidemiology
These tumours most commonly affect
young to middle aged adults; however,
the youngest reported patient was a
newborn {2916}. There is no sex
predilection. A number of these tumours
are asymptomatic and are discovered
incidentally at autopsy {1205}.
Clinical features
Symptomatic patients present with recurrent
episodes of hematuria. Colicky pain
may also be noted, caused by the passage
of blood clots. In addition to sporadic
tumours, haemangiomas may be
part of a syndrome such as Sturge-
Weber syndrome, Klippel-Trenaunay
syndrome and systemic angiomatosis.
Macroscopy
Haemangiomas are generally unilateral
and single, but may rarely be multifocal
or bilateral {2573,2916}. The largest haemangioma
reported to date was 18 cm in
greatest diameter {2875}. Renal pyramids
and renal pelvis are the most common
sites of involvement, rarely these
tumours may be found in the renal cortex
or the renal capsule {2779}. On cut section
they are unencapsulated, have a
spongy red appearance, or may be
apparent as a small red streak.
Histopathology
Both capillary and cavernous haemangiomas
have been reported, the latter
being more common. A case of intravascular
capillary haemangioma, arising in a
renal vein, and presenting as a renal
mass has also been reported {1145}.
They exhibit the typical histologic features
of haemangiomas, i.e, irregular
blood-filled vascular spaces lined by a
single layer of endothelial cells. They
may show an infiltrative growth pattern,
but lack the mitosis and nuclear pleomorphism
seen in angiosarcomas.
Lymphangioma
S.M. Bonsib
Definition
Lymphangioma is a rare benign renal
tumour that may arise from the renal capsule,
develop within the cortex, or most
often, present as a peripelvic or renal
sinus mass.
ICD-O code 9170/0
Epidemiology and etiology
These lesions are more common in
adults. Children account for 1/3 of cases.
Some cases may develop secondary to
inflammatory lower urinary tract diseases,
or represent a developmental
abnormality in lymphatic formation. A
bilateral presentation in children is
referred to as lymphangiomatosis {1462}.
Some cases appear neoplastic with karyotype
abnormalities such as monosomy
X, trisomy 7q, and defects in the von
Hippel Lindau gene {358,578}. They are
usually treated by nephrectomy because
preoperative investigations cannot distinguish
them from a malignant neoplasm.
Macroscopy
Lymphangiomas are encapsulated, diffusely
cystic lesions ranging from small
well-delineated tumours to large (19 cm)
lesions that replace the entire renal
parenchyma {89,1867,2921}.
Histopathology
The cysts communicate, contain clear
fluid, and are composed of fibrous septae
lined by flattened endothelium that is
factor VIII and Ulex europaeus agglutinin
positive but cytokeratin negative. The
fibrous septa may contain small bland
entrapped native tubules and lymphoid
cells. Smooth muscle may be present as
in lymphangiomas elsewhere.
Leiomyoma / Haemangioma / Lymphangioma
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