Introduction:
Cutaneous leishmaniasis (CL) is endemo-epidemic in the center and south of Tunisia. We report a verrucous form mimicking squamous cell carcinoma.
Case presentation:
A 80- year old woman with no medical record is presented to our department for a 3-month history of budding tumor on her left leg. It had started as a papule which progressively enlarged and became verrucous. Physical examination shows a painless verrucous mass measuring 5 cm in diameter, on the external face of the left leg’s lower extremity (Figure 1). There were no palpable regional nodes. The leg lesion was biopsied (Figure 2, 3). Histopathology revealed epidermal hyperkeratosis with a dense inflammatory infiltration of lymphocytes, plasmocytes and histiocytes (Figure 2) containing intracellular basophilic small and rounded structures which turned blue after Giemsa’s staining; these organisms were consistent with leishmaniaamastigotes (Fig.3). The diagnosis of verrucous and pseudotumoral cutaneous leishmaniasis (CL) was established. The patient was treated by cryotherapy once a week for 4 months with good results: the lesion has almost been completely resolved at 5 months, leaving a dyschromic scar.
Discussion:
Leishmaniasis is a protozoan infection that occurs worldwide. It has diverse clinical presentations and may represent a public health problem in endemic countries [1]. Various clinical forms can be encountered such as: the ulcerated and crusted form, the lupoïd form, the sporotrichoïd form and other rare forms (eczematiform, erysipeloid, psoriasiform, verrucous, and pseudotumoral) [2]. These uncommon presentations represent 2-5% of CL clinical presentations [3]. Small number of cases of verrucous and tumor-like forms had been reported in previous series [2]. The most important differential diagnosis is the verrucous variant of squamous cell carcinoma [4]. The diagnosis of CL may be made using several methods. The most common ones are tissue smear and skin biopsy with Giemsa staining in order to identify Leishmania amastigotes. The culture enables to identify the specimen but PCR has a higher sensitivity.  The treatment of CL can be topical or systemic. Cryotherapy alone can be efficient, particularly in the case of a small number of lesions [5]. Most of the published cases of verrucous CL were treated systemically [2,3,4].
The peculiarity of our case consists in its striking resemblance to verrucous squamous cell carcinoma which refers to the verrucous and pseudotumoral presentation, and the response to cryotherapy without need for systemic treatment.