Carcinoma del conducto salival: estudio clínico/patológico e inmunohistoquímico de 5 casos / Salivary duct carcinoma: a clinicopathologic and inmunohistochemical study of 5 cases

El carcinoma del conducto salival es un tumor epitelial maligno agresivo, que involucra principalmente a la glándula parótida, con características histológicas semejantes al carcinoma ductal de glándula mamaria. El propósito de este trabajo fue presentar los resultados clínico-patológicos de cinco casos de carcinoma del conducto salival primario de glándula parótida y evaluar la expresión de Ki67. Histológicamente, el carcinoma del conducto salival presentó nidos epiteliales con patrones papilar, sólido y cribiforme, comedonecrosis tanto en la lesión primaria como en los nodos linfoides metastásicos y, además, invasión perineural. Se demostró con Ki 67 una alta proliferación celular en cuatro (80 %) de los cinco casos estudiados. Se concluyó que: el carcinoma del conducto salival es una lesión maligna de mal pronóstico, raramente informado en la literatura odontológica, con características histológicas semejantes a las del carcinoma ductal de alto grado de la mama; la comedonecrosis es un signo específico de esta enfermedad; puede desarrollarse "de novo" o en un adenoma pleomórfico preexistente; su diagnóstico diferencial histopatológico es fundamental para planificar su tratamiento y determinar su pronóstico, a pesar de su tratamiento quirúrgico y radioterapia postoperatoria es un tumor agresivo con alta proliferación celular, infiltración perineural, recurrencias y metástasis.

Salivary duct carcinoma is an aggressive malignant epithelial tumor, primarily involving the parotid gland, with histologic features similar to ductal carcinoma of the breast. The purpose of this work was to report the clinicopathological results of five cases of primary salivary duct carcinoma of the parotid gland and evaluate the expression of Ki67. Histologically, salivary duct carcinoma presented epithelial nests with papillary, solid, and cribriform patterns, with comedonecrosis in both the primary lesion and the metastatic limph nodes, and perineural invasion. A high cell proliferation was demonstrated with Ki67 in four (80 %) of the five cases studied. We concluded that: salivary duct carcinoma is a malignant lesion with a poor prognosis, rarely reported in the dental literature, with histological characteristics similar to those of high-grade ductal carcinoma of the breast; comedonecrosis is a specific sign of this disease; may develop "de novo" or in a pre-existing pleomorphic adenoma; its differential histopathological diagnosis is essential to plan its treatment and determine its prognosis; despite its surgical treatment and postoperative radiotherapy, it is an aggressive tumor with high cell proliferation, perineural infiltration, recurrences and metastasis.

Squamoid eccrine ductal carcinoma

Abstract Squamoid eccrine ductal carcinoma is an eccrine carcinoma subtype, and only twelve cases have been reported until now. It is a rare tumor and its histopathological diagnosis is difficult. Almost half of patients are misdiagnosed as squamous cell carcinoma by the incisional biopsy. We report the thirteenth case of squamoid eccrine ductal carcinoma. Female patient, 72 years old, in the last 6 months presenting erythematous, keratotic and ulcerated papules on the nose. The incisional biopsy diagnosed squamoid eccrine ductal carcinoma. After excision, histopathology revealed positive margins. A wideningmargins surgery and grafting were performed, which again resulted in positive margins. The patient was then referred for radiotherapy. After 25 sessions, the injury reappeared. After another surgery, although the intraoperative biopsy showed free surgical margins, the product of resection revealed persistent lesion. Distinction between squamoid eccrine ductal carcinoma and squamous cell carcinoma is important because of the more aggressive nature of the first, which requires wider margins surgery to avoid recurrence.