Pathways Case Studies: October 2019

A 52-year-old woman presents with progressive numbness involving the right side of her face and tongue, diplopia, swallowing difficulty, and gait instability. She has an avidly enhancing extra-axial mass in the right cerebellopontine angle.

(See below for representative images and links to virtual slides from the case)

	Amy Swanson, M.D. Fellow, Anatomic Pathology/Neuropathology Mayo Clinic
	Aditya Raghunathan, M.D., M.P.H. Consultant, Anatomic Pathology Mayo Clinic Assistant Professor of Laboratory Medicine and Pathology Mayo Clinic College of Medicine and Science

A 65-year-old woman had a 12 year progressive history of ascending numbness and tingling of the left, then right side of her body. Multiple physicians were consulted and diagnoses were considered, but the correct diagnosis was not entertained for 8 years until a sural nerve biopsy was performed showing these findings (Figure 1, LFB-PAS, Scale bar 40µm). An autopsy showed these findings in her brain (Figure 2, LFB-PAS, Scale bars 200µm and 40µm). Genetic testing and enzyme activity testing made the diagnosis.

	Matthew (Matt) Ball, D.O., M.S. Fellow, Neuropathology Mayo Clinic
	R. Ross Reichard, M.D. Consultant, Anatomic Pathology Mayo Clinic Associate Professor of Laboratory Medicine and Pathology Mayo Clinic College of Medicine and Science

A 61-year-old male developed flu-like symptoms with persistent cough. He had an episode of hemoptysis and presented for evaluation in the clinic. A chest x-ray showed a left lower lobe consolidation. A chest computed tomography (CT) scan revealed an 8.5 cm left lower lobe mass which was biopsied via bronchoscopy (Figure 1A). In addition to other ancillary testing, conventional chromosome analysis was performed which revealed the following modal karyotype: 44-45,Y,t(X;18)(p11.2;q11.2),add(2)(q37),-6,add(6)(q13),add(11)(q13),-13,+0-1r[cp20] (Figure 1B).

	Patrick Blackburn, Ph.D. Fellow, Laboratory Genetics and Genomics Mayo Clinic Assistant Professor of Laboratory Medicine Mayo Clinic College of Medicine and Science @SNP_Dogg
	Rhett Ketterling, M.D. Consultant, Laboratory Genetics and Genomics Mayo Clinic Professor of Laboratory Medicine and Pathology Mayo Clinic College of Medicine and Science

A 32-year-old G1P0 woman has an initial type and screen at her first prenatal appointment. She is B positive and her antibody screen is negative. On subsequent ultrasound, she is found to be pregnant with trichorionic triamniotic triplets (2 boys and 1 girl). She has routine prenatal care and requires no transfusions during her pregnancy. She carries the pregnancy until 34 weeks gestation when she has premature rupture of membranes. Given the babies’ positions on ultrasound, she proceeds to have a Caesarian section performed to deliver the triplets. Another type and screen is collected just prior to her Caesarian section, but this time the antibody screen is strongly positive. Her initial antibody identification panel is shown in Figure 1 (top).

A cold autoantibody is suspected and further supported by a positive monospecific anti-C3 DAT and a negative monospecific anti-IgG DAT. To facilitate performing an alloadsorption with phenotypically similar RBCs, RBC antigen phenotyping is performed on the mother. The mother’s RBC antigen phenotype is shown in Figure 1 (bottom).

Following an alloadsorption with enzyme-treated phenotypically similar RBCs that adsorbs the cold autoantibody, a new alloantibody (anti-Fy3) is detected within the adsorbate. Hemolytic disease of the newborn (HDN) is now a possibility for her newly born children (each of which weighs ~2 kg). An initial ABORh typing on each of the triplets reveals one is B positive, one is AB positive, and one is A negative.

	Justin Juskewitch, M.D., Ph.D. Fellow, Transfusion Medicine Mayo Clinic Instructor in Laboratory Medicine and Pathology Mayo Clinic College of Medicine and Science
	Camille van Buskirk, M.D. Consultant, Transfusion Medicine Mayo Clinic Assistant Professor of Laboratory Medicine and Pathology Mayo Clinic College of Medicine and Science

A 64-year-old man was found to have an incidental liver mass on ultrasonography during a work-up for chronic kidney disease. He had a history of alcohol use, which he discontinued in 2011. On further evaluation, his liver function tests (ALT, AST, total bilirubin, and alkaline phosphatase) were within normal limit. Tests for hepatitis B and C viral infection were negative. CA 19-9, CEA, and alpha-fetoprotein were all within the normal reference range. On imaging, there was an indeterminate mass in the posterolateral right hepatic dome, measuring approximately 6.3 x 5.6 cm. We received a liver V and VIII segmentectomy, showing a single 5.9 x 5.5 x 4.6 cm red-yellow, friable, encapsulated mass, which was present at 0.5 cm form the inked margin.

	Aqsa Nasir, M.B.B.S. Fellow, Surgical Pathology Mayo Clinic
	Saba Yasir, M.B.B.S. Consultant, Anatomic Pathology Mayo Clinic Assistant Professor of Laboratory Medicine and Pathology Mayo Clinic College of Medicine and Science

A woman in her 60s presents with a mass in the left lobe of the thyroid and lymph node metastases. Upon thyroidectomy, the tumor histologically was composed almost entirely of complex papillary and micropapillary structures consisting of follicular cells with eosinophilic cytoplasm and apical nuclei with prominent nucleoli, decreased nuclear to cytoplasmic ratio, and loss of cellular cohesion.

	Matthew Woge, M.D. Resident, Anatomic and Clinical Pathology Mayo Clinic
	Lori Erickson, M.D. Consultant, Anatomic Pathology Mayo Clinic Professor of Laboratory Medicine and Pathology Mayo Clinic College of Medicine and Science