Sánchez Magallán-González Rodrigo¹, Robles-Lomelín Pilar¹, Rivera-Monroy Germán², López-Gil Salvador³

¹Internal Medicine Department, Centro Médico ABC, Mexico City.

²Internal Medicine Department, Médica Sur, Mexico City.

³Nephrology, Centro Médico ABC, Mexico City.

Corresponding author: López-Gil Salvador, Nephrology, Centro Médico ABC, Mexico City, Sur 136 No. 116, Las Américas, Álvaro Obregón, 01120, Cd. de México, e-Mail: salvadorlgil@gmail.com.

Citation: Sánchez Magallán-González Rodrigo, Robles-Lomelín Pilar, Rivera-Monroy Germán, López-Gil Salvador (2026). Clear Cell Renal Carcinoma Pituitary Recurrence Presenting as Panhypopituitarism Manifested as Chronic Diarrhea: A Case Report and Brief Literature Review.. Euro J Case Rep Clin Imag. 2026; November, e22,1-4.

Copyrights: © López-Gil Salvador, 2026, et al., This article is licensed under the Creative Commons Attribution-Non Commercial-4.0-International-License-(CCBY-NC) (https://europeanjournalofcasereports.com/blogpage/copyright-policy). Usage and distribution for commercial purposes require written permission.

ABSTRACT

Background. Clear cell renal carcinoma is the most common histologic subtype of renal cell carcinoma and has the worst overall survival. Metastatic disease may develop in 20 to 40% of patients after radical nephrectomy. Pituitary metastasis is a rare presentation.

Objective. To report a case of pituitary metastatic recurrence of clear cell renal carcinoma that presented as panhypopituitarism, with chronic diarrhea as the main manifestation.

Case description. A 70-year-old man with type 2 diabetes mellitus, hypertension, multifactorial chronic kidney disease, and a right radical nephrectomy one year earlier for clear cell renal carcinoma, with no evidence of recurrence on follow-up, presented to the emergency room with general malaise and chronic watery diarrhea, weight loss, fatigue, and diplopia. He had bitemporal hemianopsia, right third and sixth cranial nerve palsies, and a right pupil unresponsive to light, consistent with cavernous sinus syndrome and partial Horner syndrome. Magnetic resonance imaging showed an extra-axial mass infiltrating the hypophyseal fossa. Panhypopituitarism was documented (decreased morning cortisol, central hypothyroidism, hypogonadotropic hypogonadism, and elevated prolactin); with stress-dose hydrocortisone and levothyroxine, symptoms and blood pressure improved. A transnasal biopsy confirmed metastatic recurrence of clear cell renal carcinoma. Nivolumab and directed gamma knife radiotherapy were offered.

Conclusions. Pituitary metastases are rare. We report an unusual presentation: chronic diarrhea as the main sign of panhypopituitarism secondary to pituitary recurrence of clear cell renal carcinoma.

Keywords. Carcinoma, Renal Cell; Panhypopituitarism; Pituitary Neoplasms; Diarrhea; Neoplasm Metastasis.