NSIPTs have been reported in association with some other systemic vasculitis: granulomatosis with polyangiitis 1920, eosinophilic granulomatosis with polyangiitis 21, giant cell arteritis 2223, and Takayasu's disease 24.

The chronic inflammation of the different tissues, the vascular damage, and the immune dysfunction which characterize these affections are the main factors incriminated in the development of these pseudotumors. In addition, there is a potential genetic susceptibility and an indirect involvement of certain used therapies 122526. All these hypothetical factors of this tumorogenesis-like are validated in patients with BD; this is why some authors think that the association between NSIPT and BD is far from being a mere coincidence 12.

Several findings from our literature review reinforce this hypothesis of a causal link between BD and NSIPT; it is mainly about:

The scarcity of these two conditions: BD is a rare vasculitis with a prevalence which does not exceed 8 to 37/10,000 inhabitants 2728. Cardiac NSIPTs are also exceptional 293031, and since their first description in 1975 by Gonzalez-Crussi F 32, fewer than 30 cases have been reported 31. Thus, and given the extreme rarity of simultaneously having these two conditions "as a mere coincidence" in the general population, the potentially "promoting" character of the development of cardiac NSIPT presented by this angiitis seems highly probable,

The epidemiological characteristics: the epidemiological characteristics of the cardiac NSIPT associated with BD are clearly different from those conventionally observed for the NSIPT in the general population: in fact, in the general population, the NSIPT are a pathology of the child and the adolescent 2633343536, while our review of the literature showed a clear predominance of these pseudotumours in the adult with BD. Concerning the sex, in the general population NSIPTs affect both sexes equally 2633343536, whereas in patients with BD, the distribution of cardiac NSIPT shows a clear male predominance (sex ratio=2) similar to the distribution of the underlying vasculitis which once again reinforces the causal link,

The localizations of NSIPTs in the heart: the localization of these NSIPT associated with the BD is different from that observed in the general population: in the general population, the auricles represent the classic site of predilection 2930 whereas the involvement of the right ventricle remains exceptional 30. These data contrast sharply with cardiac NSIPT’s features during BD with right ventricular involvement in the majority of cases (83%) and no atrial involvement.

The significant difference in clinico-epidemiological characteristics between cardiac NSIPT occurring during BD compared to those in the general population, as well as the observed number of cases of NSIPT associated with BD, which appears to be far greater than the number theoretically expected because of the very rare prevalences of the two affections, strongly suggest a direct causal link between BD and the secondary appearance of these NSIPT. Pathogenic mechanisms common to these two conditions reinforce this hypothesis (immunological, inflammatory, vasculitic, reactive, and infectious) 62526.

The main problem posed by this association is a problem of differential diagnosis with cancers occurring during BD, especially since a carcinogenic potential of this vasculitis is currently strongly advanced by several authors 37; indeed, in large series, cancer occurs in 1.8% to 3.25% of patients with BD 3839. These malignant neoplasms have been reported in different organs and tissues in patients with Behçet's disease 37384041.

This differential diagnosis is often difficult to make because of the absence of specific clinical, biological or radiological signs of the NSIPT.

In addition to primary or secondary cardiac tumors 18; other differential diagnoses of NSIPT during BD are mainly organized or unorganized intracardiac thrombus 4243, an infectious endocarditis 1617 and endomyocardial fibrosis in its pseudo-tumoral form, which is another common complication of BD 444546.

In cases of cardiac NSIPT occurring during the course of BD, the lack of knowledge of the underlying pathology, particularly in the inaugural forms of the disease, led to excessive and unnecessary surgical procedures, sometimes with rapid recurrence after surgery 15161718. Thus, some authors advocate that BD, even in the absence of classical clinical signs, be considered as a differential diagnosis of any mass of the right ventricle occurring in the young subject particularly in the Mediterranean and the Middle East 42.

Regardless of the location, treatment of NSIPTs is still controversial and poorly codified; surgical excision is the treatment of choice 26.

In the forms of NSIPT associated with BD, the treatment is mainly based on systemic corticosteroid therapy at high doses, sometimes initiated by intravenous methylprednisolone boli 8, and associated with long-term immunosuppressive drugs. The most commonly used are monthly cyclophosphamide boli and oral azathioprine 918.

Biotherapy may be suggested as a second-line treatment for NSIPTs occurring during BD and resistant to conventional first-line treatment, with satisfactory results 47.

Surgery is only available in complicated life-threatening forms 48; the systemic vasculitis that characterizes this disease often exposes to operative complications and local recurrences 234. The majority of surgical procedures found in the literature for these cardiac NSIPTs associated with BD were mainly performed for the inaugural forms of the disease and for fear of a malignant neoplastic process 612161718.

Thus some authors recommend, especially for the cardiac localizations, to evoke and to look for BD in case of any unexplained heart mass, before considering a surgical excision sometimes heavy and serious 18.

Cardiac NSIPT associated with BD were characterized by a generally favorable prognosis; locoregional recurrence remains rare 15. Prolonged follow-up (clinical and radiological) remains however necessary because of the unpredictable evolution of these pseudotumors.