Organ-specific histology Practice Questions

Q: A 32-year-old woman presents with amenorrhea and galactorrhea. MRI shows a pituitary adenoma. Histological examination of the surgical specimen shows cells arranged in cords and nests with sinusoidal capillaries. Special staining reveals three distinct cell types: chromophobes (50%), acidophils (40%), and basophils (10%). Immunohistochemistry shows the tumor cells staining strongly for prolactin. Evaluate the relationship between normal pituitary architecture and tumor development to determine which cell type most likely gave rise to this neoplasm.

Lactotrophs (acidophils producing prolactin). ***Lactotrophs (acidophils producing prolactin)*** - These cells are classified as **acidophils** based on their staining characteristics and are responsible for the secretion of **prolactin**, consistent with the patient's **amenorrhea** and **galactorrhea**. - Although the tumor specimen contains various cell types, the **immunohistostaining** specifically identifying **prolactin** confirms these cells as the source of the neoplasm. *Somatotrophs (acidophils producing growth hormone)* - While these are also **acidophilic** cells, they secrete **Growth Hormone (GH)**, and a tumor of this type would present with **acromegaly** or gigantism rather than galactorrhea. - They do not typically stain for **prolactin**, unless the tumor is a rare plurihormonal adenoma, which is not indicated here. *Corticotrophs (basophils producing ACTH)* - These cells are **basophils** and produce **ACTH**; an adenoma arising from them would lead to **Cushing's disease** due to hypercortisolism. - Histologically, they would not correspond to the strong **prolactin** staining observed in this immunohistochemical evaluation. *Gonadotrophs (basophils producing FSH/LH)* - These are **basophilic** cells that produce **FSH** and **LH**, and tumors originating from them are usually non-functional or present with mass effects rather than hormonal excess. - They are clinically and histologically distinct from **prolactin-producing** lactotrophs. *Chromophobes (null cells with no secretory granules)* - **Chromophobes** lack significant cytoplasmic staining due to a lack of hormone granules; they often represent cells that have depleted their secretory stores. - While they occupy 50% of the specimen, the **strong prolactin staining** identifies the active neoplastic process as originating from the hormone-producing lineage.

Q: A 35-year-old woman with hyperthyroidism undergoes thyroid biopsy. Microscopy shows follicles of varying sizes lined by cuboidal epithelium. The follicular lumens contain eosinophilic colloid material. In her condition, the follicular cells have become columnar with scalloped colloid borders and decreased colloid content. Analyze these changes and determine which cellular process is most enhanced?

Thyroglobulin endocytosis and hormone release. ***Thyroglobulin endocytosis and hormone release*** - In hyperthyroidism (such as **Graves' disease**), high activity leads to **scalloped margins** of the colloid, which represent active **endocytic vacuoles** consuming thyroglobulin. - Transition from cuboidal to **columnar epithelium** and decreased colloid volume indicate an enhanced rate of thyroid hormone secretion into the bloodstream. *Follicular cell apoptosis* - **Apoptosis** would lead to a decrease in cell number and glandular atrophy, whereas hyperthyroidism typically displays **hyperplasia** and hypertrophy. - The histological signs of **scalloping** and increased cell height are markers of high metabolic activity, not programmed cell death. *Parafollicular cell calcitonin secretion* - **Parafollicular cells** (C-cells) are responsible for **calcitonin** production, which regulates calcium levels and is not directly involved in thyroxine (T4) hyperthyroidism. - The description specifically mentions **follicular cell** morphology and changes in the **colloid**, which are unrelated to C-cell function. *Interfollicular fibrosis* - **Fibrosis** is a characteristic of chronic inflammatory conditions like **Riedel thyroiditis**, not the active secretory state of hyperthyroidism. - Active hyperthyroidism typically shows **increased vascularity** and cellularity rather than the deposition of dense connective tissue. *Colloid synthesis and storage* - While synthesis occurs, the hallmark of this histological picture is the **rapid depletion** and utilization of colloid, rather than its accumulation. - Inactive follicles or **hypothyroidism** typically show flattened cells and **distended lumens** due to excessive colloid storage.

Question 1

A 32-year-old woman presents with amenorrhea and galactorrhea. MRI shows a pituitary adenoma. Histological examination of the surgical specimen shows cells arranged in cords and nests with sinusoidal capillaries. Special staining reveals three distinct cell types: chromophobes (50%), acidophils (40%), and basophils (10%). Immunohistochemistry shows the tumor cells staining strongly for prolactin. Evaluate the relationship between normal pituitary architecture and tumor development to determine which cell type most likely gave rise to this neoplasm.

Accepted Answer

Lactotrophs (acidophils producing prolactin)

Answer

Somatotrophs (acidophils producing growth hormone)

Answer

Corticotrophs (basophils producing ACTH)

Answer

Gonadotrophs (basophils producing FSH/LH)

Answer

Chromophobes (null cells with no secretory granules)

Question 2

A 65-year-old man with progressive shortness of breath undergoes transbronchial biopsy. Microscopy shows thickened alveolar septa with increased collagen deposition. Type I pneumocytes are decreased, and there is proliferation of type II pneumocytes. Alveolar macrophages are present. The patient has a history of environmental asbestos exposure 30 years ago. Evaluate the histological progression and synthesize the most likely diagnosis considering the temporal relationship and cellular changes.

Accepted Answer

Asbestosis with interstitial fibrosis and ferruginous bodies

Answer

Chronic hypersensitivity pneumonitis with granulomas

Answer

Idiopathic pulmonary fibrosis with usual interstitial pneumonia pattern

Answer

Sarcoidosis with non-caseating granulomas

Answer

Acute respiratory distress syndrome with diffuse alveolar damage

Question 3

A 40-year-old woman presents with difficulty swallowing. Esophageal biopsy shows non-keratinized stratified squamous epithelium in the upper two-thirds and columnar epithelium with goblet cells in the lower third. Submucosal glands are present throughout. Evaluate these findings and synthesize a diagnosis considering the clinical significance of the epithelial transition zone.

Accepted Answer

Barrett esophagus with intestinal metaplasia requiring surveillance

Answer

Normal histological finding representing the gastroesophageal junction

Answer

Esophageal stricture with squamous hyperplasia

Answer

Normal columnar epithelium of the lower esophageal sphincter

Answer

Eosinophilic esophagitis with epithelial transformation

Question 4

A 50-year-old man with chronic pancreatitis undergoes pancreatic biopsy. Microscopy shows distinct acinar cells with basophilic basal cytoplasm and eosinophilic apical zymogen granules. Scattered among the acini are pale-staining clusters of cells with few granules and rich capillary networks. Immunostaining reveals insulin, glucagon, somatostatin, and pancreatic polypeptide in different cells within these clusters. Analyze the microarchitecture and predict which histological feature best explains the systemic effects of a tumor arising from these clusters?

Accepted Answer

Rich fenestrated capillary network allowing direct hormone entry to bloodstream

Answer

Lymphatic drainage to regional nodes for hormone distribution

Answer

Autonomic nerve fiber density for neurocrine release

Answer

Direct connection to pancreatic ducts for hormone delivery

Answer

Gap junctions with acinar cells for paracrine signaling

Question 5

A 35-year-old woman with hyperthyroidism undergoes thyroid biopsy. Microscopy shows follicles of varying sizes lined by cuboidal epithelium. The follicular lumens contain eosinophilic colloid material. In her condition, the follicular cells have become columnar with scalloped colloid borders and decreased colloid content. Analyze these changes and determine which cellular process is most enhanced?

Accepted Answer

Thyroglobulin endocytosis and hormone release

Answer

Follicular cell apoptosis

Answer

Parafollicular cell calcitonin secretion

Answer

Interfollicular fibrosis

Answer

Colloid synthesis and storage

Organ-specific histology — MCQs

Organ-specific histology — MCQs

On this page

Practice by Chapter

Want unlimited practice?