Splenic cord capillary hemangioma and anemia: resolution after splenectomy

Controversies in the Spleen: Histiocytic, Dendritic, and Stromal Cell Lesions

Histiocytic, dendritic, and stromal cell lesions that occur in the spleen are challenging diagnostically, not well studied due to their rarity, and therefore somewhat controversial. New techniques for obtaining tissue samples also create challenges as splenectomy is no longer common and needle biopsy does not afford the same opportunity for examination of tissue. Characteristic primary splenic histiocytic, dendritic, and stromal cell lesions are presented in this paper with new molecular genetic findings in some entities that help differentiate these lesions from those occurring in non-splenic sites, such as soft tissue, and identify possible molecular markers for diagnosis.

A case of cord capillary hemangioma of the spleen: a recently proven true neoplasm

Cord capillary hemangioma (CCH) of the spleen is an extremely rare lesion. Once classified under splenic hamartoma, CCH is now differentiated from hamartoma, as its clonality has recently been proven. Herein, we present the case of an incidentally found CCH, measuring 6 × 5.5 × 5 cm, in a 45-year-old man. He underwent splenectomy and has been recurrence-free for 8 years. Macroscopically, the cut surface of the mass showed a central stellate scar with peripheral interspersed reddish areas of variable sizes and intervening fibrous bands. Microscopically, the mass was well demarcated from the splenic tissue. The macroscopic reddish areas were found to correspond to nodules of various sizes, which were predominantly composed of CD34-expressing capillaries without the presence of CD8-expressing sinuses. The relative proportion of these two types of vessels distinguishes CCH from sclerosing angiomatoid nodular transformation (SANT), as SANT shows the apparent presence of CD8-expressing sinuses. In longstanding cases of SANT, sinuses might become ambiguous and the differences between CCH and SANT might become subtle. Nonetheless, immunohistochemistry should be performed when these conditions are suspected, since accurate distinction is usually achieved as a result.

Laparoscopic excision of a giant splenic vascular tumor

The splenic vascular tumor referred to as a hemangioma is rare and typically presents as a small asymptomatic lesion. We report a case of a giant splenic cyst in a 13-year-old boy with abdominal distension. He underwent laparoscopic excision of the splenic cyst without complication. Pathology revealed a vascular tumor. At 15 months of follow-up, he continued to be asymptomatic, and abdominal ultrasound showed no recurrence of his disease. Laparoscopic excision of giant splenic cysts is a viable option in children, allowing for preservation of normal splenic tissue.

Clonal X-chromosome inactivation suggests that splenic cord capillary hemangioma is a true neoplasm and not a subtype of splenic hamartoma

Splenic hamartoma is a rare tumor-like lesion composed of structurally disorganized red pulp elements. It has been hypothesized that two other splenic lesions, cord capillary hemangioma and myoid angioendothelioma, may fall within the spectrum of splenic hamartoma, simply representing morphological variants. In this study, we compared the vascular and stromal composition of cord capillary hemangioma and myoid angioendothelioma with those of classical hamartoma. In addition, we assessed the clonal vs polyclonal nature of the lesions in nine female cases by performing clonality analysis for X-chromosome inactivation at the human androgen receptor locus (HUMARA) on laser-assisted microdissected samples. In 15 of 17 cases, increased reticulin and/or collagen content was observed. The classical hamartoma cases showed a vasculature predominantly composed of CD8+ CD31+ CD34- splenic sinuses, whereas cases of cord capillary hemangioma and myoid angioendothelioma contained many CD8- CD31+ CD34+ cord capillaries, but very little CD8+ vasculature. All cases lacked expression of D2-40 and Epstein Barr virus-encoded RNA. All cases showed a proliferation index of ≤5% by Ki-67. Cases of classical hamartoma lacked significant perisinusoidal expression of collagen IV and low-affinity nerve growth factor receptor. Both markers were variably expressed in the other lesions. Increased CD163-positive histiocytes were found in four cases (three cord capillary hemangiomas and one myoid angioendothelioma). HUMARA analysis was informative in all nine tested cases, of which three cases showed a non-random X-chromosome inactivation pattern, indicating clonality. All three clonal cases were cord capillary hemangiomas. Our study has shown that in spite of considerable morphologic heterogeneity and overlapping features, classical hamartoma and cord capillary hemangioma and myoid angioendothelioma are different in terms of their vascular and stromal composition. Clonality analysis supports a true neoplastic origin for the cord capillary hemangioma. A larger study using additional immunohistochemical and molecular studies is necessary to further evaluate the biological significance of the current findings.

Esplenectomia parcial para tratar hemangioma esplênico

Apesar de a esplenectomia ser eficaz na abordagem terapêutica de pacientes com hemangioma esplênico, esse procedimento é acompanhado de elevada morbidade e até mortalidade, principalmente devido à sepse, quando realizado em crianças e adolescentes com sistema imunitário ainda imaturo. Para prevenir os efeitos adversos da asplenia, propõe-se neste artigo a esplenectomia parcial, com a retirada apenas da região do hemangioma, mantendo o restante do baço e preservando suas importantes funções.