Nasosinus Metastases from Breast Cancer: A Review of Two Cases

Context: Breast cancer affects more than 2 million women a year worldwide. Improved treatments have made it possible to increase survival rates with more and more patients having time to develop secondary locations. Nasosinus metastases from this cancer are rare. Two recently treated breast cancer patients developed metastases to the sphenoidal and maxillary sinuses. These cases gave rise to an examination of the incidence of this disease, its diagnosis, the therapeutic means envisaged and the fate of these patients. Method: We report the diagnostic and therapeutic data of two patients suffering from breast cancer and presenting metastases at the nasosinus level, with a focus on the interest of radiotherapy in palliative care. Results: The two patients aged 56 and 60 presented in the course of their breast cancer secondary localizations in the sphenoidal and maxillary sinus confirmed by endoscopy and histology. All the cases presented massive lesions associated with other secondary bone locations in particular. After local radiotherapy and systemic chemotherapy treatment, one patient died 5 months after her diagnosis and the other was alive 16 months later. Conclusion: Nasal and sinus metastases from breast cancer are rare and have a poor prognosis as disseminated disease, they do not respond well to conventional systemic therapies even if palliative radiotherapy allows local control.

Advances in Breast Cancer Research recent years [1]. Improved treatments have made it possible to increase survival rates with more and more patients having time to develop secondary locations.
Nasosinus metastases from breast cancer are exceptional. Only a few cases of paranasal breast cancer metastases have ever been published [2] [3] [4]. The mechanism of paranasal sinus metastases is unclear. Hematogenous spread through the spine via the venous plexus has been advanced [5]. The Valsalva maneuver can cause retrograde flow through a low-pressure, valveless system, which communicates with the venous system of the thorax and transports tumor emboli to the pterygoid plexus and paranasal sinuses [5] [6]. We report the diagnostic and therapeutic data of two patients suffering from breast cancer and having presented metastases at the nasosinus level in the course of their disease.

Clinical Case 1
A 56-year-old woman was admitted to the Oto-Rhino-Laryngology department of the National University Hospital (NUH) of Fann and then referred to the ra-

Clinical Case 2
A 60-year-old patient was admitted to the Otorhinolaryngology department and then to radiotherapy at the Dalal Jamm University Hospital in Dakar for a

Discussion
Breast cancer in women has now overtaken lung cancer in terms of incidence in 2020, with around 2.3 million new cases, or 11.7% of all cancer cases. It is the fifth leading cause of cancer death worldwide, with 685,000 deaths [1]. Improved treatment of this disease led to better survival, indirectly giving more time for the appearance of unusual secondary locations. Hematogenous metastases from breast cancer could affect virtually any anatomical site in the body, but most commonly occur in bone, lungs and liver [4].
Nasosinus metastases from this cancer are rare. It occupies the fourth position as the starting point of secondary tumors of the frontal and ethmoidal sinuses, behind cancers of the kidneys, bronchi, and thyroid gland [7].
The clinical symptoms are not specific and may be confused with those of other tumors in the region of the facial mass. The table consists mainly of mainly unilateral nasal symptoms including rhinorrhea, nasal obstruction and epistaxis, which may be associated with mass syndrome [8], with neurological, ophthalmological or cutaneous manifestations. The proximity to the orbit can then cause compression or invasion leading to ocular symptoms: exophthalmos, diplopia and blindness [7]. In some cases reported in the literature, the symptomatology has wrongly suggested the diagnosis of ethmoiditis [2], treatment-resistant subacute sinusitis, or cavernous sinus thrombophlebitis with neurological and ophthalmological signs [8]. The diagnosis of these secondary nasosinus localizations is often concomitant with other metastatic bone and visceral lesions which largely determine the patient's prognosis. The therapeutic strategy generally includes: local treatment with radiotherapy for analgesia and local control to avoid serious functional or vital complications and systemic treatment with palliative chemotherapy even if the response to systemic treatment remains weak [10]. In our patients, hypofractionated radiotherapy made it possible to obtain a rapid analgesic effect and significant local control even if one of the patients died 5 months after the diagnosis. It is important to emphasize that the prognosis of these patients is poor and that in the majority of published cases the overall survival at 1 year was zero [3] [8] [10]. A patient was still alive in good general condition 16 months after the onset of nasosinus metastases and this after hypo-fractionated local radiotherapy, sequential chemotherapy type 4AC60 + 4 Taxotere + 6 Zometa and mastectomy.left of cleanliness.

Conclusion
Nasosinus metastases of breast cancer are very rare but possible, this diagnosis should be evoked before any nasosinus manifestation in a patient with a history of breast cancer, which would make it possible to make an early diagnosis and avoid as much possible as locoregional complications. Despite the poor prognosis generally associated with this picture due to generalized disease, radiotherapy offers good local control.

Ethical Considerations
The informed consent of the two patients was obtained at the diagnosis before the writing of these clinical cases.