Skin Myasis Associated with High-Risk Epidermoid Carcinoma in a Possible Lung Metastasis Patient.

Introduction

Myiasis is an ectoparasitic infestation by diptera larvae of higher flies of the genus Dermatobia. It can be a complication of malignant lesions and an association has been seen with skin cancers, mainly those affecting the head and neck; of these, epidermoid carcinoma is one of the most frequently associated with this complication.[1]

Clinical Case

A 70-year-old male with a dermatosis located on the head, which affected the right fronto-temporo-parietal region characterized by an 8 × 8 × 2 cm3 exophytic neoformation, was selected. In addition, erythematous ulcerated bleeding surface with serous and fetid secretion was observed on which mobile larvae were found inside [Figures 1 and 2].

Figure 1

Patient with multiple myiasis in ulcerated squamous cell carcinoma in the right-frontal-temporo-parietal region

Figure 2

Patient with squamous cell carcinoma and healing of myiasis

The accessible larvae were removed and ivermectin 12 mg was given orally in a single dose with complete cure of the myiasis [Figure 3]. The histopathological report of the tumor was well-differentiated invasive squamous carcinoma with positive lateral and deep surgical borders [Figures 4 and 5]. In extension studies, lung metastases were determined [Figure 6]. Therefore, It was sent to oncology for pharmacological treatment to reduce the size of the tumor and to perform excision.

Figure 3

Patient with post-chemotherapy squamous cell carcinoma

Figure 4

H-E section showing loss of polarity and cellular pleomorphism affecting the epidermis and dermis

Figure 5

H-E section showing cell pleomorphism, atypical cells, dyskeratosis

Figure 6

Pulmonary computerized axial tomography of patients with squamous cell carcinoma and myiasis

Discussion

Female flies have a strong visual and olfactory attraction to blood and decaying tissue; they are also attracted to tumor cell metabolites, which may explain the propensity of ulcerated malignant tumors to be parasitized. The preferred treatment is mechanically removing the larvae with forceps.[2] Patel et al. recommend using ivermectin, albendazole, and clindamycin to eradicate the infestation.[3] It is important to mention that the extension of the head tumor and the invasion of multiple myiases make the case presented an unusual presentation and of immediate approach.[4]

Conclusion

Myiasis may be a rare complication in patients with large, ulcerated, and necrotic squamous cell carcinoma. The goal of treatment is to remove all larvae to avoid deep invasion and bleeding. Large and invasive malignant tumors outside of surgical treatment require classification and referral to the oncologist for pharmacological management.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.