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Sites
Venous aneurysms can occur at any site. In the lower limbs, they have been reported in the
popliteal vein, the femoral vein, the great saphenous vein, the small saphenous vein (2), foot
veins and the superficial communicating veins of the legs. In the pelvis they have been
reported in the external and internal iliac veins (3). In the neck they are commonly found in
the internal jugular vein (4), the external jugular vein (5,6), anterior jugular vein (7), the
facial vein and the parotid gland veins. In the upper limbs, they have been reported in the
subclavian vein, the cephalic vein, the basilic vein, and the brachial vein. Intra-abdominally
they have been reported in the superior vena cava (8), the inferior vena cava, the superior
mesenteric vein, the portal vein (9), and the splenic vein and in the chest in the azygos
venous system (10). About 60% of them are found in the deep venous system of the lower
extremities and the remaining 40% are distributed in the rest of the venous system (11).
Pathology
The pathogenesis of these rare lesions is unknown. There is elastic tissue dysplasia and
smooth muscle fiber fragmentation, both of which are replaced by fibrous tissue. The
tunica media exhibits a reduced number of muscle fibers. Congenital focal defects of the
elastic and muscle fibres have been proposed to contribute to the development of venous
aneurysms (12).
Presentation
The most common presentations of venous aneurysm are pain (75%), swelling (67%) and
a mass (42%) (11). However, there are region specific presentations and venous aneurysms
in the lower limbs, and the pelvis can present with deep venous thrombosis. In a review of
117 patients with popliteal venous aneurysm by Sessa et al. 45% presented with
pulmonary embolism, 26% with chronic venous disease (phlebitis, pain, and ulcer) and
26% with varicose veins (13). Most of the popliteal aneurysms were associated with
varicose veins and were more common in females. Venous aneurysms of the neck veins
present with swelling in almost all the published cases and are most often found in the
internal jugular vein. The abdominal, pelvic and thoracic vein aneurysms are most often
identified as incidental findings during routine diagnostic investigations for other diseases.
Complications
The most serious complication of venous aneurysm of the lower limb, abdominal and
pelvic veins is pulmonary embolism. Cardiac arrest and death have been reported due to
the thrombo-embolic events as complication of these aneurysms. Deep venous thrombosis
and chronic venous disease (phlebitis, pain swelling, ulcers) are the most common
complications. Paradoxical embolus via a patent foramen ovale has been reported leading
to hemiplegia (14,15).
Nerve compression syndromes due to venous aneurysms have also been reported.
They include radial nerve compression by cephalic vein aneurysm (16), tibial nerve
compression by popliteal vein aneurysm (17), median nerve compression by brachial vein
aneurysm (18), and brachial plexus compression by a subclavian vein aneurysm (19).
Investigations
Color duplex scan has been found to be accurate and sufficient in diagnosing limb venous
aneurysms. It not only enables diagnosis but also provides valuable information on site,
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size, patency, the presence of thrombus, valve status and flow dynamics that are useful for
managing these aneurysms (Fig. 1). Venographic methods have also been employed in a
number of case studies in diagnosis and assessment of these aneurysms. However, not only
is venography invasive but also does not give any information to the clinician about the
haemodynamic status of the veins.
Other modalities such as contrast enhanced magnetic resonance imaging (MRI) and
computed axial tomography (CAT) may need to be employed in certain circumstances
and they have been found to be accurate in diagnosing venous aneurysms within the thorax
and abdomen. However, CAT and MRI have been employed mostly when venous
anomalies are identified incidentally during the diagnostic investigation of abdominal
mass, some other disease or suspicious shadows on plain X-rays. In abdominal, pelvic and
thoracic venous aneurysms, CT and MRI scans may perhaps be the most appropriate
methods of investigations, given the limitations of other methods such as ultrasound,
venogram, etc.
Treatment
Treatment of venous aneurysm is varied. The vast majority can be managed conservatively
except deep venous aneurysms of the lower limbs. For popliteal vein aneurysm, surgery is
the treatment of choice as they usually present with thrombosis and embolism which could
be life threatening. The method of choice is tangential aneurysmectomy and lateral
venorrhaphy. Other methods employed are resection with end-to-end anastomosis and
resection with vein interposition graft (13). In a large retrospective study and review,
surgery has mostly been the treatment of choice and this has been found to be effective in
managing most such venous aneurysms (20,21).
Pelvic and abdominal vein aneurysms have usually been managed conservatively as
well as surgically, but the vast majority of surgeons prefer surgery to conservative
Figure 1 Ultrasound B-mode image of a great saphenous aneurysm. This was found in the lower
thigh of a female patient who presented with local pain over the aneurysm. It measured 25!22 mm.
The aneurysm was pushing the saphenous fascia and distorted the local anatomy in the saphenous
canal. No varicose veins were found in either extremity. There was no thrombosis but only mild
reflux exiting through a medial tributary. The diameter of the saphenous vein above and below the
aneurysm measured 4.6 and 4.1 mm, respectively. The patient did not want any treatment, and she
was scheduled to have follow-up once a year.
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management because of the increased risk of thrombosis and embolism and rupture (21).
Tangential excision and lateral venorrhapy or poly-tetra-fluoroethylene (PTFE)
interposition graft have been employed in their surgical management.
Thoracic venous aneurysms can be managed conservatively. Most of the surgery
is for rupture and increasing size, which are not common (21).
Neck vein aneurysms have been excised in most of the case reports. Most of these
neck venous aneurysms have been found in the younger age group. Cosmetic appearance
is the only indication for surgery and this is by surgical excision and direct suture
(4,22,23). However the majority of these can be treated conservatively with routine follow
up (24–26).
Blue Rubber Bleb Nevus Syndrome
Blue rubber bleb nevus syndrome (BRBNS) is a rare congenital venous disorder
characterized by cutaneous and gastrointestinal venous malformation. It is associated
with intestinal hemorrhage and iron deficiency anemia. It was first recognized by
Gascoyen in 1860 and in 1958 Bean further described these lesions and coined the term
BRBNS (27).
The cause of this syndrome is unknown. The majority of cases occur sporadically
but Gallione et al. have studied two families with venous malformation syndrome and
found a linkage to chromosome 9p (28). Vikkula et al. concluded that these families had an
activating mutation in the tyrosine kinase (TIE2) receptor that participates in abnormal
angiogenesis (29).
Cutaneous Lesions
In BRBNS, lesions are usually multiple and characteristically consist of deep-blue blebs
which are soft and rubbery and are easily compressible.
They can be found anywhere over the body surface but the majority of them are
located most commonly on the upper extremities and trunk. The size of the skin lesions
varies from a few millimeters to 5 cm or more. They are usually covered with a layer of
skin of varying thickness and in contrast to the gastrointestinal lesions they rarely
bleed spontaneously.
Cutaneous lesions are of three types:
1. A large disfiguring lesion that may compress the surrounding tissues
2. A typical red to blue–violet nodule or macule covered with skin
3. An irregular macule or papule that may punctuate or merge with adjacent nevi
These cutaneous lesions are soft and are most often asymptomatic. The lesion can be
emptied of blood on pressure. Excessive sweating has been described to occur from the
overlying skin due to the close association of the nevi with sweat glands (30).
Gastrointestinal Lesions
These are again characteristically multiple and can occur anywhere from the mouth to
the anus. The commonest occurrence of these lesions is in the small bowel. In the colon
they have a predilection to the left side. The typical mucosal lesion is a nodule similar to
the cutaneous lesion with a bluish tinge covered by a thin layer of mucosal cells. They
may also appear as a bluish–red spot or polypoid lesions. They can bleed spontaneously
and are a cause of gastrointestinal hemorrhage and iron deficiency anemia.
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Presentations and Complications
The most common presentation in the skin is the obvious lesion, but in the gastrointestinal
tract,anemia and frank bleedingare the presenting features. Theyconstitute one of rare causes
of bleeding in the gastrointestinal tract in infants, children and young adults (31–36). These
lesions are also known to occur in the kidneys giving rise to hematuria in the brain leading to
intracranial hemorrhage causing ataxia, dementia, focal neurological signs and symptoms
(37) and in the vulva they can cause severe bleeding and distress (38). They have also been
reported to cause consumptive coagulopathy (39), a cause of massive gastrointestinal
bleeding (40), and endobronchial involvement leading to chronic cough (41).
Investigations
The skin lesions are obvious but the most common manifestation is anaemia and
gastrointestinal bleeding and for this gastrointestinal endoscopy is the investigation of
choice in the upper and lower gastrointestinal tract. In the small bowel, endoscopic
techniques such as wireless capsule endoscopy and push enteroscopy have been employed
in the investigation and wireless capsule endoscopy in particular has been found to be
quite accurate in the diagnosis (42). In intracranial and intra-abdominal lesions other
methods such as CAT and MRI angiography may be necessary for diagnosis. In certain
circumstances technetium labeled red cells have been used to delineate the lesions at times
of active bleeding (43).
Treatment
The cutaneous lesions do not usually cause any symptoms except occasional pain and
discomfort. No reports of thrombosis in these lesions have been noted so far. They very
rarely bleed spontaneously, however trauma to these lesions may cause profuse bleeding.
Resuscitation with fluids, blood and blood products is the goal of treatment of
gastrointestinal bleeding. Specific treatment of gastrointestinal bleeding due to BRBNS
includes: sclerotherapy, rubber band ligation and argon beam laser coagulation of the
lesions. In intractable cases bowel resection may have to be undertaken to control the
bleeding. Multiendoscope (simultaneous use of laparoscope and gastrointestinal
endoscope) assisted resection of these lesions in the gastrointestinal tract has also been
undertaken with good results (44).
Congenital Angiodysplasias
These are congenital vascular anomalies encompassing three variations in presentation (45).
1. Klippel–Trenaunay syndrome (KTS).Thisconsistsofatriadofvaricosity,
hemangioma and hypertrophy of soft tissues and bones.
2. Parks-Weber syndrome. This consists of hypertrophy of the lower limbs with
hemodynamically active congenital arterio-venous fistulae, usually of an intra-
and extraosseous location.
3. Servelle-Martorell type. This consists of hemangiomatosis usually of a venous
(cavernous) type, affecting soft tissues as well as bones in association with skeletal
hypoplasia. There is a retardation of bone growth by substitution and destruction
of the epiphysial cartilages by the intraosseous hemangioma.
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From a clinical perspective, this classification has little relevance because manage-
ment of these in most cases are identical. Hence all these are clubbed and termed Klippel–
Trenaunay–Weber syndrome or just Klippel–Trenaunay syndrome.
In 1988 the Hamburg Classification came into existence and is the most
comprehensive classification and is based on clinical, anatomical and pathophysiological
features of the disease. This classified all congenital vascular malformations into five groups
based on the predominance of the anatomic component: arterial, venous, atreriovenous
shunting, lymphatic, and combined (hemolymphatic). Each one of these is further classified
into “Extratruncular form” and “Truncular form.” The extratruncular form develops from
the embryonic remnant because of the developmental arrest during the embryonic life. This
embryonic remnant originates from the mesodermal cells and hence retains the capacity of
organogenesis and to differentiate further at a later stage in life when subjected to various
normal physiological stimuli. However the truncal form lacks this feature of differentiation
as it is a growth defect which occurs at later stages of embryonic life and hence lacks the
capacity to differentiate (46,47).
Klippel–Trenauny Syndrome
KTS was originally described in 1900 and is characterized by a constellation of three
anomalies (1) soft tissue and bony hypertrophy of the extremity, (2) cutaneous vascular
naevi of the affected extremity mainly of the port-wine stain type and (3) varicose veins and
lymphatic anomalies. The other added features are clinically absent aterio-venous shunting
and the presence of deep venous anomalies which include atresia, hypoplasia or aneurysmal
dilatation of the deep veins, external compression by fibrous bands, valvular incompetence
or agensis (48,49).
Etiology. The etiology of KTS is still obscure. A number of theories have been
hypothesized, some of them quite controversial. One of the suggested theories is that KTS is
due to an embryogenic abnormality of the vascular system at the mesodermal level (45,50).
Much genetic research has been undertaken to understand the etiology of KTS, but so
far it has remained elusive. A few cases have been thought to be due to an autosomal
dominant gene with low penetrance. Berry reviewed 49 cases of KTS and found that all of
them were sporadic and suggested that it was due to somatic mutation (51).
Angiogenic factors critical in the initiation and maintenance of vascular architecture
have been studied. Two genetic defects of angiogenic factor VG5Q have been identified in
patients with KTS, i.e., excessive expression and enhanced activity. The autocrine effect of
VG5Q promotes uncontrolled vascular proliferation. Two mutations have been identified,
one of these is chromosomal translocation (5:11) which increases the VG5Q transcription
and the second mutation is E133K which enhances the angiogenic effect of VG5Q. In
addition, the angiogenic factor TNFSF-12 also called TWEAK interacts with VG5Q to
summate the angiogenic effect (52). However, none of these have been demonstrated
consistently in KTS.
Clinical Features. In addition to the venous malformation, KTS is not uncommonly
associated with lymphatic malformations. In a study of 252 patients, 63% had the triad of
varicose veins, limb hypertrophy and cutaneous vascular naevi, 37% had just two of the
triad, however in 94% of patients with KTS, one of the triad was noted shortly after birth
(53). None of the reports show any gender differences nor significant family history. Lower
limbs are more often affected (88% to 95%), unilateral involvement occurs in 85% of cases,
upper and lower limb involvement in 15% of cases, and all four extremity involvement is
very rare (49,53,54).
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Due to the venous congestion and the lymphedema, pain, heaviness and fatigability
are some of the common presenting complaints.
Capillary Malformation. This is the commonest of the triad of KTS and occurs in
62% (49). It presents as a port-wine patch which is red to purple in color, flat and has an
irregular distribution. On the trunk it has a clear sharp border and does not cross the midline
whereas in the extremities it has a patchy distribution. In addition to skin, the subcutaneous
tissue, muscles, abdominal and thoracic cavities can be also involved (54). These capillary
malformations, although they do not disappear, they may however fade significantly on
aging. In addition they can bleed, develop skin atrophy, hyperhidrosis, infection etc (53,54).
Venous Anomalies. The venous anomalies in KTS are mainly varicosities. Unlike
common varicose veins these are extensive and large. They take an erratic course and begin
in childhood. Trelat and Monod described the “vein of Servelle” which is a large dilated vein
starting from a plexus of veins over the dorsum of the foot running laterally over the lower
limbs before entering the deep system at sites such as the profunda vein, popliteal vein,
superficial femoral or the iliac system via the gluteal veins. In 33% of cases it extends the
whole length of the lower extremity terminating in the iliac vein system (55).
In a study involving 144 patients with KTS, it was observed that the lower limbs were
the more commonly affected. In the 559 operations performed for KTS by Servelle, he has
observed that the commonest veins affected in the lower limbs was the popliteal (54).
The other commonly described anomalies of the venous system in KTS are
hypoplasia, agenesis, venous and valvular incompetence and aneurysmal dilation of the deep
venous system. Other frequently occurring defects are fibrous bands and hypoplasia.
Servelle in 448 operations for KTS has observed that in the popliteal veins, the lesions were
compression and fenestration in 71%, peirvenous sheath in 15% and the remaining 14%
accounts for hypoplesia and agensis. In 252 operations on the superficial femoral vein,
compression and fenestration were observed in 54%, hypoplasia in 41% and perivenous
sheath and agensis in the remaining 5%. Whereas in the 19 operations on iliac veins,
hypoplesia accounts for 63% and agenesis for 37%. In the upper limbs, in 80 patients, the
brachial and axillary veins were involved in the pathology, compression in 63%, hypoplasia
in 22% and agenesis in 15% (48).
Limb Hypertrophy. This usually manifests at a later age in life. Soft tissue, bone or
both may be involved. Increase in limb length is due to involvement of bone whereas
increase in the girth is due to the soft tissue involvement. In 144 patients, limb hypertrophy
has been observed in 93%. Increase in the length was observed in 66% and increase in the
girth in 69% (49).
Other Anomalies. Anomalies of the lymphatic in KTS are the most common and
can be disabling. The most common anomalies are aplasia, hypoplasia and a decrease in the
number of lymph trunks and lymph nodes are noticed in 70% of patients. Cutaneous
lymphatic vesicles, cutaneous lymphatic leakage can occur due to the associated
lymphatic abnormalities.
Complications. At least one episode of deep vein thrombosis and thrombophlebitis
occurs in 17% of patients with KTS and venous thrombosis has a potential risk of throwing
pulmonary emboli.
Bleeding from hemangioma can cause rectal, vaginal, vulvar or esophageal bleeding
and hematuria due to pelvic vein involvement that accounts for 23% (49). Hematochezia is
a common form of bleeding in KTS. The pathophysiology is the internal iliac vein
normally drains the rectal, pudendal, vesicular and genital veins. In KTS, the lateral vein in
the lower limbs and the sciatic vein form the posterior venous system. They unite in the
thigh and divide to enter the superior and the inferior sciatic notch to join the internal iliac
vein. The internal iliac vein in turn is overloaded by these veins and hence its normal
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draining tributaries become varicose with concomitant bleeding and hematochezia and
hematuria (56).
Cavernous hemangiomas can enlarge rapidly, usually in the first year of life,
producing high-output congestive heart failure or a consumptive coagulopathy (Kasabach–
Merritt syndrome). This syndrome is marked by anemia, thrombocytopenia, prolonged
prothrombin time (PT) and activated partial thromboplastin time (APTT), reduced levels
fibrinogen and fibrin split products.
Investigation. Diagnosis of KTS is clinical. However, investigations are only
needed to identify any surgically correctable lesions and, if surgery is indicated, to assess the
feasibility and the extent of surgery because the majority of patients with this disorder are
managed conservatively. Generally color duplex scanning is sufficient to map the venous
anomaly. Venogram and contrast enhanced MRI scans may be needed in identifying the
architecture, the defect and the extent of the lesions. Lymphangiogram and lymphoscinti-
graphy may delineate the lymphatic defects and may help in managing the patients.
Scanogram of the skeletal system and CT scans may be helpful in identifying the skeletal
discrepancy and help in determining the timing of surgery (51,53).
Treatment. KTS is a life-long disease. To date there is no treatment available to
completely cure the abnormality. Patients have to learn to live with the anomaly. There are a
number of KTS support organizations that are helpful in bringing together patients and
helping them to understand the disease, provide psychological support and disseminate
information, and also keep them updated with ways of adjusting and managing their
life styles.
Common presenting complaints in KTS are due to varicosities of the lower limbs and
cosmetic appearance. The majority of the patients can be treated symptomatically with
support stockings, elevation, rest and continued reinforcement to wear graduated
compression stockings. The secondary effects of varicosities such as phlebitis, cellulitis
and ulcers are treated with antibiotics and compression. Surgery has been undertaken in the
past for KTS. Servelle has reported remediable causes for the venous congestion and
varicosities in the lower limbs such as bands, perivenous sheath, hypoplasia and agenesis.
He claims that resolving these anomalies can improve the venous circulation and varicosity
(48). Treating varicosities with traditional varicose vein surgery—vein stripping, ligation,
and multiple stab avulsions—is fraught with the risk of worsening the situation with
development of new varicosities, difficulties of wound healing, bleeding, infection etc (57).
Sclerosing agents (sodium tetradecyl sulphate, ethanolamine oleate) have been used with
some success in obliterating the varicosities. In one study 44% of the venous malformation
over the face disappeared and 28% decreased on foam sclerotherapy (58). In another study
1% polidocanol has been used and has shown promising results (59).
Capillary malformations usually diminish in size and appearance on aging. However,
they present a common problem in the earlier years. Surgery should be withheld, as it is
complicated with bleeding, non healing wounds, ulcers etc. With the advent of laser therapy
many of these disfiguring appearances could be minimized. Ordinary pulse dye laser has not
shown to be effective in improving the port wine stain (60). Flashlamp pump dye laser has
found to be quite effective in treating port wine staining in childhood, (61,62) although it
may darken and thicken the skin. A multilayer technique has been developed that seems to
cause less skin damage (63). However the intelligent application of modern cosmetic
products helps in masking these lesions to almost invisibility.
Hypertrophy and limb elongation are usually treated based on the degree of
overgrowth. A discrepancy of less than 2 cm length can be adjusted by altering the soles of
the shoes. Greater than 2 cm may need surgical correction (53). A number of methods have
been employed. Servelle showed thatligating the deep veins of the opposite leg increased the
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limb length of that leg compensating for the over growth of the anomalous leg in 48 children
(48). However, this is not the standard current practice. Limb length discrepancy is tailored to
the needs of individual patient. Predicting the overgrowth is difficult in children and it is still
debated as to when, how and where intervention should be undertaken. Current practice is to
cause epiphyseal arrest by stapling of the epiphysis but this is not always effective.
Epiphysiodesis described by Mullikne and Young is considered to be more reliable and
permanent (64). However, prior to undertaking such surgery, scanogram and CAT may be
useful in determining the best time for this procedure.
Lymphedema is usually managed with compression stockings, massage and surgery is
rarely indicated. General skin care and prevention of trauma is important to prevent the
complications of healing, ulcers, infection etc.
Gastrointestinal bleeding usually stops spontaneously. Esophageal varices may need
sclerotherapy or rubber band ligation. Hemorrhoidal bleeds can be similarly managed.
Occasionally in rectosigmoid bleeding, rectosigmoidectomy may have to be undertaken to
control the bleeding (56).
VENOUS TUMORS
Venous tumors are one of the rarest neoplasms encountered in venous clinical practice.
They are either benign or malignant, however most venous tumors are malignant. They
arise from the tissues of the vessel wall and they include endothelioma from the
endothelial lining of the tunica intima, fibrosarcoma from the connective tissue of all the
three layers, and leiomyoma and leiomyosarcoma from the smooth muscles of the tunica
media. Leiomyosarcoma is the most common among these rare neoplasms. Two cases of
primary malignant lymphoma of the veins have also been reported (65,66).
Leiomyosarcoma
The commonest site of occurrence of these tumors is in the inferior vena cava and in the
extremities thegreat saphenous vein(67). Their occurrencein the azygos vein (68) pulmonary
veins (69), femoral vein, internal jugularvein (70),portal vein (71), renal vein(72), iliac veins
(73), and ovarian vein (74) has also been reported. Potentially they can occur in any vein.
Leimyosarcoma of the inferior vena cava is the more common (60% overall); 80% of
these occur in women and the majority of them have been detected in the elderly (75). The
mean age of detection in two big reviews was between 50 and 60 years (76,77). In the
extremities they occur more commonly in the great saphenous vein.
The distribution of primary IVC leiomyosarcoma is described in relation to the renal
and hepatic veins: segment I infrarenal, segment II suprarenal, and segment III suprahepatic
(78). The majority of them are intramural but intravenous extension of these tumors have
also been reported (79).
Histology
The tumor consists of an elongated pinkish-white, lobulated, moderately circumscribed, and
encapsulated fibrous mass. Histologically they consists of hyperchromatic, enlarged, solid
spindle-cell lesion with elongated spindled irregular nuclei arranged in interwoven fascicles
with small focal areas of necrosis. The smooth muscle cells are typical for leiomyoma with a
whorled pattern without nuclear pleomorphism. Mitotic activity is no greater than 1 per 15
high-power fields. The tumor cells display desmin, vimentin, and smooth muscle cell actin
but not S-100 protein (80,81).
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Figure 2 Klippel–Trenauny syndrome. (A) Young female patient with hypertrophy of the left
lower extremity, staining of the skin, and varicose veins. The lateral thigh veins were enlarged and
had reflux. The femoral vein was hypoplastic. (B) Thrombosis of the lateral vein in a young male. He
also had bleeding in the intestine and for this reason an IVC filter was placed. (See color insert.)
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Clinical Presentation
Clinically they are often asymptomatic and hence remain undetected for great periods. They
may present as a palpable mass (40% to 80%), back pain (70%) or abdominal pain (60%).
Suprarenal inferior vena caval involvment may present as renal failure however this is
infrequent because of the rich collateral network retroperitonially via the left renal vein (75).
Although obstruction of the hepatic veins is uncommon, this has been reported in 36
patients. In these cases the clinical symptoms may present as an acute or chronic form of
Budd-Chiari syndrome (82–85). These tumors can invade the right atrium and patients may
present with acute heart right heart failure, with symptoms similar to pulmonary
hypertension or pulmonary embolism.
These tumors are slow growing and there is usually adequate time for the development
of venous collateral circulation and as a result clinical presentation with signs and symptoms
of acute deep venous obstruction is rare. Lower limb swelling is more frequent if the iliac or
femoro-popliteal veins are invaded. Primary tumors of the superficial leg veins usually
present as a painless mobile mass, whereas those arising from deep veins can be fixed to the
surrounding tissues (86,87).
Investigations
Ultrasound scan, contrast enhanced CAT, and MRI are usually sufficient in delineating these
lesions. As they are retroperitoneal other surrounding structures such as ureter, aorta, bowel,
biliary structures may be involved in the disease process hence intravenous urography,
angiography, barium examination, etc. may also be useful in assessing their involvement.
However, a definitive diagnosis can often only be made on histopathological examination of
the resected specimen. Duplex scan may be useful in assessing the venous anatomy
and hemodynamics.
Treatment
Resection of the neoplasm is the treatment of choice. After resection, the caval defect can be
dealt with caval interruption, patch repair, or interposition graft using spiral saphenous vein
or ePTFE prosthetic graft. Recently several studies have shown that reconstructing the
inferior vena cave with prosthetic material is not only possible but also the graft patency
maintained is good (88,89). Due to the close proximity of other important anatomical
structures, nephrectomy, cholecystectomy, hepatectomy may have to be undertaken to free
the margins. However vena caval reconstruction should be selective. If the pre operative
investigations shows that the vena cava is occluded without secondary effects this could be
safely treated with caval interruption, as there are usually enough venous collaterals to
prevent secondary effects of interruption (75). Given the median survival of about
three years, the longest survival has been recorded to be 13 and 17 years after resection
(75,90).
Adjuvant treatment such as radiotherapy and chemotherapy can be instituted but they
have not shown to be of much benefit.
Leiomyoma
Intravenous leiomyomatosis is an extremely rare, benign, well-differentiated tumor that can
cause venous obstruction or cardiac irritability due to its propensity to extend into the inferior
vena cava andto the rightheart. The tumor isconfined to thevascular channels (91).Although
they are benign, they can recur. This disorder is more common in women who have had
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