Diffuse cavernous haemangioma of the recto-sigmoid colon: CT and MRI findings

A 59-year-old male patient with clinical suspicion of ulcerative colitis since 1978, without histology, treated intermittently with Sulfasalazine. On admission, the patient presented bloody diarrhoea, weight loss, and fatigability. Physical examination revealed a subponderal and pale patient. Rectal examination showed a smooth, nodular, compressible mass and red blood.

CT with retrograde negative contrast opacification (1.5l water) and iodinated non-ionic contrast i.v. injection (1.5ml/kgc), in axial plane (Fig.1a, b, c). Sagittal reconstructions (Fig.1d,e) demonstrate symmetrical circumferential parietal thickening of the recto-sigmoid, densification of the mesorectal fat, in association with numerous phleboliths in the rectal and sigmoid colon walls and in the adjacent adipose structures.

Pelvis MRI evaluation using T2 weighted images (wi) in axial (Fig.2a,b), coronal oblique (Fig.2c) and sagittal plane (Fig.2d), diffusion (Fig.2e) with ADC map (Fig.2f) in sagittal plan and 3D T1 Fat Sat pre-/ and post extracellular paramagnetic contrast i.v.injection, in axial (Fig.3a,b), sagittal (Fig. 3c,d) and coronal plane (Fig. 3f): marked and uniform circumferentially parietal thickening of the recto-sigmoid with T2 hyperintensity (arrows), linear and serpiginous structures in the peri- / mesorectal fat (arrowhead).

Colonoscopy (Courtesy to Prof.C.Gheorghe). Starting from the mucocutaneous line there is a circumferential rectal and sigmoid lesion with friable mucosa, spontaneous mucosal bleeding and multiple hemorrhagic dots (Fig.4).

Background. Diffuse cavernous hemangioma of rectum and sigmoid colon (DCHRSC) is a rare disease arising from the submucosal vascular plexus that are attributable to embryonic sequestration of mesodermal tissue [1-3]. This type of pathology affects mainly young adults, characterized by the clinical triad of recurrent episodes of painless, rectal bleeding, multiple ectopic phleboliths on CT evaluation, and cutaneous hemangiomas (3). The mortality in untreated cases is around 50% due to the risk of bleeding of this lesion [2]. Cavernous hemangiomas are composed of large thin-walled vascular channels and have no capsule. DCHRSC can occur as solitary or multiple lesions. There may be synchronous lesions of the stomach and small intestine or be a part of a multicentric process with involvement of the spleen, kidney, brain, and skin [1-4]. Chronic iron deficiency anaemia, bowel obstruction, intussusception, perforation, and consumptive coagulopathy has been reported as complications of DCHRSC [4,6,7].

Imaging modalities: CT, MRI.

CT diagnostic. Pathognomonic CT findings consist of transmural heterogenous enhancing, bowel-wall thickening containing multiple small rounded punctate calcifications corresponding to phleboliths (Fig.1a-c). CT is the most sensitive imaging modality to detect the phleboliths in the areas of the thickened bowel wall, and in the adjacent fatty structures (fig.1d,e). The extramural extension can be accurately evaluated using CT [5,6, 8-9].

MRI diagnostic. The MRI features are represented by markedly thickened and T2 hyperintensity of the rectosigmoid colonic walls associated with T2 hyperintensity of perirectal fat, which has heterogeneous appearance, containing serpiginous structures (Fig.2a-c). Diffusion and ADC map doesn’t show any water restriction of the recto-sigmoid lesions. T1 Fat Sat wi after contrast paramagnetic i.v, (Fig.3) in sagittal and coronal plane highlight a heterogeneous transmural enhancement of the recto-sigmoid walls (arrows) in association with abnormal heterogeneous perirectal fat-containing multiple linear and serpiginous vessels (arrowhead). The regional arteries or veins are with normal caliber [1,7].

On colonoscopy, cavernous hemangiomas present as nodular, compressible lesions that are deep blue to dull red and are associated with mucosal congestion and oedema. Chronic inflammatory changes often mask findings that could lead to proper diagnosis. Biopsy may cause profuse haemorrhage [1,4].

Treatment is correlated with the site and extent of the lesions. Many therapeutic techniques have been tried in DCHRSC : angiographic embolization, sclerotherapy, ligation of mesenteric vessels, radiotherapy. Surgical resection of the affected rectum and colon is generally the treatment of choice [1,3,4].

Take-Home Message / Teaching Points. DCHRSC is a rare cause of rectal bleeding. The thickening of the recto-sigmoid walls and phleboliths are easily seen on CT. In preoperative, MRI represents the imaging modality of choice to diagnose and assess the full extent of the DCHRSC.