A 40-year-old man comes to the physician because of a 1-month history of a painless lump on his neck. Two years ago, he underwent surgery for treatment-resistant hypertension, episodic headaches, and palpitations. Physical examination shows a firm, irregular swelling on the right side of the neck. Ultrasonography of the thyroid gland shows a 2-cm nodule with irregular margins and microcalcifications in the right thyroid lobe. Further evaluation of this patient is most likely to show increased serum concentration of which of the following substances?
Q122
A 66-year-old man presents to his family physician complaining of a sandpaper-like sensation when he touches the lesion on his forehead. His medical history is relevant for hypertension and hypercholesterolemia, for which he is taking losartan and atorvastatin. He used to work as a gardener, but he retired 3 years ago. His vital signs are within normal limits. Physical examination of his forehead reveals male-pattern baldness and thin, adherent, yellow-colored skin lesions that feel rough to the touch (see image). His family physician refers to him to a dermatologist for further management and treatment. Which of the following conditions would the patient most likely develop if this skin condition is left untreated?
Q123
A 75-year-old woman comes to the physician because of a 3-month history of involuntary weight loss and a painless lump on her neck. Physical examination shows a firm, irregular swelling on the right side of the neck. Ultrasonography of the thyroid gland shows a 2-cm nodule with irregular margins and microcalcifications in the right thyroid lobe. A biopsy of the thyroid nodule is performed. Which of the following changes would be most consistent with anaplasia?
Q124
A 44-year-old man comes to the physician because of fatigue and increased straining during defecation for 3 months. During this time, he has lost 5 kg (12 lb) despite no change in appetite. He has a family history of colon cancer in his maternal uncle and maternal grandfather. His mother died of ovarian cancer at the age of 46. Physical examination shows conjunctival pallor. His hemoglobin concentration is 11.2 g/dL, hematocrit is 34%, and mean corpuscular volume is 76 μm3. Colonoscopy shows an exophytic mass in the ascending colon. Pathologic examination of the resected mass shows a poorly differentiated adenocarcinoma. Genetic analysis shows a mutation in the MSH2 gene. Which of the following is the most likely diagnosis?
Q125
A 32-year-old woman presents to her primary care physician for an annual checkup. She reports that she has been feeling well and has no medical concerns. Her past medical history is significant for childhood asthma but she has not experienced any symptoms since she was a teenager. Physical exam reveals a 1-centimeter hard mobile mass in the left upper outer quadrant of her breast. A mammogram was performed and demonstrated calcifications within the mass so a biopsy was obtained. The biopsy shows acinar proliferation with intralobular fibrosis. Which of the following conditions is most likely affecting this patient?
Q126
A 70-year-old man presents to the physician with a 1-month history of severe fatigue. During this time, he has unintentionally lost 2 kg (4.4 lb). Currently, he takes no medications other than aspirin for occasional knee pain. He does not smoke or drink alcohol. His vital signs are within the normal range. On physical examination, the conjunctivae are pale. Petechiae are present on the distal lower extremities and on the soft and hard palates. Palpation reveals bilateral painless cervical lymphadenopathy. Examination of the lungs, heart, and abdomen shows no abnormalities. Which of the following factors in this patient’s history or laboratory findings would most likely indicate a good prognosis?
Q127
A 5-year-old boy presents to his pediatrician with weakness. His father observed that his son seemed less energetic at daycare and kindergarten classes. He was becoming easily fatigued from mild play. His temperature is 98°F (37°C), blood pressure is 90/60 mmHg, pulse is 100/min, and respirations are 20/min. Physical exam reveals pale conjunctiva, poor skin turgor and capillary refill, and cervical and axillary lymphadenopathy with assorted bruises throughout his body. A complete blood count reveals the following:
Leukocyte count: 3,000/mm^3
Segmented neutrophils: 30%
Bands: 5%
Eosinophils: 5%
Basophils: 10%
Lymphocytes: 40%
Monocytes: 10%
Hemoglobin: 7.1 g/dL
Hematocrit: 22%
Platelet count: 50,000/mm^3
The most specific diagnostic assessment would most likely show which of the following?
Q128
A 10-year-old boy is brought by his mother to his pediatrician for "skin growths." His mother reports that she started noticing small lumps arising from the patient's lips and eyelids several months ago. She also notes that he seems to suffer from frequent constipation and appears "weaker" than many of his peers. The boy's past medical history is unremarkable. His father and paternal grandmother have a history of medullary thyroid carcinoma. His height and weight are in the 85th and 45th percentiles, respectively. His temperature is 99°F (37.1°C), blood pressure is 110/65 mmHg, pulse is 90/min, and respirations are 18/min. On examination, he has an elongated face with protruding lips. There are numerous sessile painless nodules on the patient's lips, tongue, and eyelids. This patient's condition is most strongly associated with a mutation in which of the following genes?
Q129
A 55-year-old man presents to the emergency department because of an excruciating headache that started suddenly after he got home from work. He also reports having double vision. Specifically, in the last week he almost got into two car accidents with vehicles that "came out of nowhere" while he was trying to merge on the highway. Physical examination is notable for ptosis of the left eye, which is also inferiorly and laterally deviated. The patient is treated emergently and then started on a hormone replacement in order to avoid life-threatening post-treatment complications. The patient's current presentation was associated with a pathologic process that existed for several months prior to this event. Which of the following symptoms could this patient have experienced as part of that pre-existing pathology?
Q130
A 3-year-old boy was brought in by his parents for undescended testes. The physical examination showed an absence of the left testis in the scrotum. Inguinal swelling was noted on the left side and was surgically corrected. Which of the following conditions will most likely occur in the later stages of his life?
Neoplasia US Medical PG Practice Questions and MCQs
Question 121: A 40-year-old man comes to the physician because of a 1-month history of a painless lump on his neck. Two years ago, he underwent surgery for treatment-resistant hypertension, episodic headaches, and palpitations. Physical examination shows a firm, irregular swelling on the right side of the neck. Ultrasonography of the thyroid gland shows a 2-cm nodule with irregular margins and microcalcifications in the right thyroid lobe. Further evaluation of this patient is most likely to show increased serum concentration of which of the following substances?
A. Thyroid-stimulating hormone
B. Gastrin
C. Parathyroid hormone
D. Metanephrines
E. Calcitonin (Correct Answer)
Explanation: ***Calcitonin***
- The patient's history of treatment-resistant **hypertension**, episodic **headaches**, and **palpitations**, for which he underwent surgery 2 years ago, is highly suggestive of a prior **pheochromocytoma**.
- The neck lump with a **thyroid nodule** showing **irregular margins** and **microcalcifications** in a patient with a history of pheochromocytoma points to **Medullary Thyroid Carcinoma (MTC)**, often part of **Multiple Endocrine Neoplasia type 2A (MEN2A)**, which is characterized by elevated **calcitonin**.
*Thyroid-stimulating hormone*
- **TSH** levels are typically normal or suppressed in differentiated thyroid cancers (papillary or follicular carcinoma) but would be elevated in primary hypothyroidism.
- MTC is a neuroendocrine tumor of the parafollicular C cells and does not generally affect TSH production, as it is not a differentiated thyroid cancer.
*Gastrin*
- Elevated **gastrin** levels are typically associated with **Zollinger-Ellison syndrome**, often caused by a **gastrinoma**, which is a feature of **MEN1**, not MEN2A.
- Gastrinomas do not present with thyroid masses or pheochromocytoma.
*Parathyroid hormone*
- While **primary hyperparathyroidism** (due to parathyroid adenoma or hyperplasia) is also a component of **MEN2A**, the primary endocrine marker for **medullary thyroid carcinoma** itself is calcitonin, not PTH.
- Elevated PTH would be expected if the patient also had hyperparathyroidism, but calcitonin directly indicates MTC.
*Metanephrines*
- **Metanephrines** (metanephrine and normetanephrine) are elevated in patients with **pheochromocytoma**, which the patient likely had in the past (hence the surgery for hypertension, headaches, and palpitations).
- However, the current presentation focuses on a new thyroid nodule, and calcitonin is the primary marker for **medullary thyroid carcinoma**, which develops in a significant proportion of patients with MEN2A.
Question 122: A 66-year-old man presents to his family physician complaining of a sandpaper-like sensation when he touches the lesion on his forehead. His medical history is relevant for hypertension and hypercholesterolemia, for which he is taking losartan and atorvastatin. He used to work as a gardener, but he retired 3 years ago. His vital signs are within normal limits. Physical examination of his forehead reveals male-pattern baldness and thin, adherent, yellow-colored skin lesions that feel rough to the touch (see image). His family physician refers to him to a dermatologist for further management and treatment. Which of the following conditions would the patient most likely develop if this skin condition is left untreated?
A. Squamous cell carcinoma (Correct Answer)
B. Mycosis fungoides
C. Seborrheic keratosis
D. Actinic cheilitis
E. Basal cell carcinoma
Explanation: ***Squamous cell carcinoma***
- The description of a **rough, sandpaper-like, yellow-colored lesion** on a sun-exposed area like the forehead, in a patient with a history of outdoor work (gardener), is highly characteristic of **actinic keratosis**.
- **Actinic keratosis** is a premalignant lesion that can progress to **invasive squamous cell carcinoma** if left untreated.
*Mycosis fungoides*
- This is a form of **cutaneous T-cell lymphoma** and typically presents as patches, plaques, or tumors that are often pruritic.
- It does not present as a rough, sandpaper-like lesion and is not directly associated with sun exposure in the same way as actinic keratosis.
*Seborrheic keratosis*
- Seborrheic keratoses are **benign epidermal tumors** that appear as "stuck-on" lesions, often waxy or greasy, and can be various shades of brown or black.
- While they can be rough, they are typically not described as "sandpaper-like" and do not carry the risk of malignant transformation like actinic keratosis.
*Actinic cheilitis*
- **Actinic cheilitis** is a variant of actinic keratosis that specifically affects the **lips**, primarily the lower lip, due to chronic sun exposure.
- While also premalignant and able to progress to squamous cell carcinoma, the lesion described in the question is on the **forehead**, not the lips.
*Basal cell carcinoma*
- **Basal cell carcinoma (BCC)** is another common skin cancer linked to sun exposure, but it typically presents as a **pearly nodule**, often with rolled borders and telangiectasias, or as a superficial red patch.
- While BCC can develop in sun-exposed areas, actinic keratosis is a direct precursor to squamous cell carcinoma, not basal cell carcinoma.
Question 123: A 75-year-old woman comes to the physician because of a 3-month history of involuntary weight loss and a painless lump on her neck. Physical examination shows a firm, irregular swelling on the right side of the neck. Ultrasonography of the thyroid gland shows a 2-cm nodule with irregular margins and microcalcifications in the right thyroid lobe. A biopsy of the thyroid nodule is performed. Which of the following changes would be most consistent with anaplasia?
A. Negative staining of tumor cells for thyroglobulin (Correct Answer)
B. Disorganized proliferation of mature thyroid cells
C. Increased expression of thyroid transcription factor-1
D. Replacement of thyroid cells by normal squamous epithelium
E. Reduced number of functional thyroid cells
Explanation: ***Negative staining of tumor cells for thyroglobulin***
- Anaplastic thyroid carcinoma is characterized by extreme **dedifferentiation**, losing most of the features of normal thyroid cells, including the ability to produce **thyroglobulin**.
- Therefore, **negative or weak staining for thyroglobulin** (a marker of thyroid differentiation) in a highly malignant thyroid tumor is consistent with anaplasia.
*Disorganized proliferation of mature thyroid cells*
- This description is more consistent with a **benign tumor** or hyperplastic nodule where cells retain their mature characteristics but grow abnormally.
- In contrast, anaplastic carcinomas involve highly **undifferentiated cells** that bear little resemblance to mature thyroid cells.
*Increased expression of thyroid transcription factor-1*
- **Thyroid transcription factor-1 (TTF-1)** is a nuclear protein expressed in various thyroid neoplasms, including well-differentiated carcinomas.
- While TTF-1 expression can occur in anaplastic carcinoma, it is usually **lost or significantly reduced** due to dedifferentiation, making increased expression inconsistent with anaplasia.
*Replacement of thyroid cells by normal squamous epithelium*
- This describes **squamous metaplasia**, a common finding in chronic inflammation or conditions like Hashimoto's thyroiditis, but it isn't anaplasia.
- Anaplastic carcinoma involves **malignant transformation** of thyroid cells into highly pleomorphic, undifferentiated cells, not replacement by normal non-thyroid cells.
*Reduced number of functional thyroid cells*
- While anaplastic carcinomas replace normal thyroid tissue, leading to a reduced number of functional cells, this is a **consequence** of the disease, not a defining characteristic of anaplasia itself.
- Anaplasia refers to the **histological appearance** of highly undifferentiated, malignant cells, rather than simply a reduction in functional cell count.
Question 124: A 44-year-old man comes to the physician because of fatigue and increased straining during defecation for 3 months. During this time, he has lost 5 kg (12 lb) despite no change in appetite. He has a family history of colon cancer in his maternal uncle and maternal grandfather. His mother died of ovarian cancer at the age of 46. Physical examination shows conjunctival pallor. His hemoglobin concentration is 11.2 g/dL, hematocrit is 34%, and mean corpuscular volume is 76 μm3. Colonoscopy shows an exophytic mass in the ascending colon. Pathologic examination of the resected mass shows a poorly differentiated adenocarcinoma. Genetic analysis shows a mutation in the MSH2 gene. Which of the following is the most likely diagnosis?
A. Familial adenomatous polyposis
B. Peutz-Jeghers syndrome
C. Turcot syndrome
D. Lynch syndrome (Correct Answer)
E. Gardner syndrome
Explanation: ***Lynch syndrome***
- The patient's **poorly differentiated adenocarcinoma** in the ascending colon, coupled with the **family history of colon and ovarian cancer** (early onset, diverse cancer types), and the **MSH2 gene mutation**, strongly indicates Lynch syndrome (hereditary nonpolyposis colorectal cancer).
- **Lynch syndrome** is caused by germline mutations in **DNA mismatch repair (MMR) genes** (e.g., MSH2, MLH1, MSH6, PMS2), leading to an increased risk of colorectal, ovarian, endometrial, and other cancers, often at a younger age and predominantly in the **right colon**.
*Familial adenomatous polyposis*
- This syndrome is characterized by the development of **hundreds to thousands of colorectal adenomatous polyps** during adolescence or early adulthood, a feature not mentioned in the patient's presentation.
- It is caused by a germline mutation in the **APC gene**, not MSH2, leading to an almost 100% lifetime risk of colorectal cancer if untreated.
*Peutz-Jeghers syndrome*
- This syndrome is characterized by **hamartomatous polyps** throughout the gastrointestinal tract and **mucocutaneous melanin pigmentation** (dark spots on lips, buccal mucosa, fingers/toes).
- It is associated with mutations in the **STK11 gene** and an increased risk of various cancers, but the clinical presentation and genetic mutation do not match.
*Turcot syndrome*
- Turcot syndrome is a rare condition characterized by the coexistence of **colorectal polyposis** (either FAP-like or Lynch-like) and **central nervous system tumors** (e.g., medulloblastoma, glioblastoma).
- While it can involve MMR gene mutations in some cases, the prominent feature of CNS tumors is absent in this patient's history.
*Gardner syndrome*
- This is a subtype of FAP, characterized by colorectal polyps along with **extra-intestinal manifestations** such as **osteomas** (especially in the mandible or skull), **epidermoid cysts**, and **desmoid tumors**.
- Like FAP, it is caused by mutations in the **APC gene**, and the characteristic extra-intestinal features are not described in the patient.
Question 125: A 32-year-old woman presents to her primary care physician for an annual checkup. She reports that she has been feeling well and has no medical concerns. Her past medical history is significant for childhood asthma but she has not experienced any symptoms since she was a teenager. Physical exam reveals a 1-centimeter hard mobile mass in the left upper outer quadrant of her breast. A mammogram was performed and demonstrated calcifications within the mass so a biopsy was obtained. The biopsy shows acinar proliferation with intralobular fibrosis. Which of the following conditions is most likely affecting this patient?
A. Sclerosing adenosis (Correct Answer)
B. Fibroadenoma
C. Cystic hyperplasia
D. Invasive lobular carcinoma
E. Infiltrating ductal carcinoma
Explanation: ***Sclerosing adenosis***
- This condition is characterized by **acinar proliferation with intralobular fibrosis**, which exactly matches the biopsy findings mentioned in the vignette.
- Sclerosing adenosis can present as a palpable mass with **calcifications on mammography**, mimicking carcinoma, necessitating biopsy for definitive diagnosis.
*Fibroadenoma*
- Characterized by proliferation of both **stromal and epithelial elements**, often forming well-circumscribed, mobile masses.
- While it can present as a mobile mass, the specific histological finding of "acinar proliferation with intralobular fibrosis" is not the primary descriptive characteristic of a fibroadenoma.
*Cystic hyperplasia*
- This term, often used interchangeably with **fibrocystic changes**, involves the formation of cysts and an increase in fibrous tissue.
- While it can involve hyperplasia, it doesn't typically describe the distinct pattern of "acinar proliferation with intralobular fibrosis" as seen in sclerosing adenosis.
*Invasive lobular carcinoma*
- This carcinoma is characterized by its **infiltrative growth pattern** often in single file lines, and typically does not form a well-defined mass.
- While it can present with calcifications, the absence of overt malignant features and the specific benign histological description rule out this diagnosis.
*Infiltrating ductal carcinoma*
- The most common type of breast cancer, characterized by **malignant epithelial cells infiltrating the stroma**.
- The biopsy findings described ("acinar proliferation with intralobular fibrosis") are features of a benign process, not a malignant one.
Question 126: A 70-year-old man presents to the physician with a 1-month history of severe fatigue. During this time, he has unintentionally lost 2 kg (4.4 lb). Currently, he takes no medications other than aspirin for occasional knee pain. He does not smoke or drink alcohol. His vital signs are within the normal range. On physical examination, the conjunctivae are pale. Petechiae are present on the distal lower extremities and on the soft and hard palates. Palpation reveals bilateral painless cervical lymphadenopathy. Examination of the lungs, heart, and abdomen shows no abnormalities. Which of the following factors in this patient’s history or laboratory findings would most likely indicate a good prognosis?
A. Leukocyte count > 100,000/mm3
B. History of myelodysplastic syndrome
C. Philadelphia chromosome
D. Prior treatment with cytotoxic agents
E. Translocation t(15;17) (Correct Answer)
Explanation: ***Translocation t(15;17)***
- This translocation is characteristic of **acute promyelocytic leukemia (APL)**.
- APL is highly sensitive to **all-trans retinoic acid (ATRA)** and **arsenic trioxide**, leading to high remission rates and a significantly better prognosis compared to other AML subtypes.
*Leukocyte count > 100,000/mm3*
- An extremely high white blood cell count in acute leukemia, especially **AML**, is generally associated with a **worse prognosis**.
- It indicates a large disease burden and increased risk of complications like **leukostasis** and disseminated intravascular coagulation (DIC).
*History of myelodysplastic syndrome*
- Myelodysplastic syndromes (MDS) often transform into **secondary acute myeloid leukemia (sAML)**.
- AML arising from MDS typically has a **poor prognosis** due to higher rates of unfavorable cytogenetics and resistance to standard chemotherapy.
*Philadelphia chromosome*
- The **Philadelphia chromosome (t(9;22))** is typically associated with **chronic myeloid leukemia (CML)** and some types of acute lymphoblastic leukemia (ALL).
- Its presence in AML is rare but is associated with an **adverse prognosis** due to its underlying genetic instability.
*Prior treatment with cytotoxic agents*
- Prior exposure to cytotoxic agents (e.g., chemotherapy for another cancer) can lead to **therapy-related AML (tAML)**.
- tAML generally has a **very poor prognosis**, often characterized by unfavorable cytogenetics and multidrug resistance.
Question 127: A 5-year-old boy presents to his pediatrician with weakness. His father observed that his son seemed less energetic at daycare and kindergarten classes. He was becoming easily fatigued from mild play. His temperature is 98°F (37°C), blood pressure is 90/60 mmHg, pulse is 100/min, and respirations are 20/min. Physical exam reveals pale conjunctiva, poor skin turgor and capillary refill, and cervical and axillary lymphadenopathy with assorted bruises throughout his body. A complete blood count reveals the following:
Leukocyte count: 3,000/mm^3
Segmented neutrophils: 30%
Bands: 5%
Eosinophils: 5%
Basophils: 10%
Lymphocytes: 40%
Monocytes: 10%
Hemoglobin: 7.1 g/dL
Hematocrit: 22%
Platelet count: 50,000/mm^3
The most specific diagnostic assessment would most likely show which of the following?
A. Bone marrow biopsy with ≥ 20% lymphoblasts (Correct Answer)
B. Fluorescence in situ hybridization analysis with 9:22 translocation
C. Peripheral blood smear with > 50% lymphoblasts
D. Flow cytometry with positive terminal deoxynucleotidyl transferase staining
E. Fluorescence in situ hybridization analysis with 12:21 translocation
Explanation: ***Bone marrow biopsy with ≥ 20% lymphoblasts***
- The patient's symptoms (weakness, fatigue, pallor, bruising, lymphadenopathy) and blood counts (anemia, thrombocytopenia, leukopenia with relative lymphocytosis) are highly suggestive of **Acute Lymphoblastic Leukemia (ALL)**.
- The most specific diagnostic assessment for ALL involves a **bone marrow biopsy** showing **≥20% lymphoblasts** per WHO 2016 classification, confirming the abnormal proliferation of immature lymphoid cells.
- This is the **gold standard** for diagnosing ALL and distinguishes it from other hematologic disorders.
*Fluorescence in situ hybridization analysis with 9:22 translocation*
- The **Philadelphia chromosome (t[9;22])** is characteristic of **Chronic Myeloid Leukemia (CML)**, which is rare in children and presents differently.
- While t(9;22) can occur in 3-5% of childhood ALL and indicates poor prognosis, it is a **prognostic marker**, not the primary diagnostic criterion for ALL itself.
*Peripheral blood smear with > 50% lymphoblasts*
- While lymphoblasts can be seen in the peripheral blood in ALL, a specific percentage threshold in peripheral blood is **not a diagnostic criterion** for ALL.
- The peripheral blood smear can be suggestive, but the **bone marrow blast percentage is the gold standard** for definitive diagnosis.
*Flow cytometry with positive terminal deoxynucleotidyl transferase staining*
- **Terminal deoxynucleotidyl transferase (TdT)** is a nuclear enzyme expressed in pre-B and pre-T lymphoblasts and is an important marker for ALL.
- Flow cytometry with positive TdT staining helps **characterize and classify the blasts** but does not quantify the blast percentage required for diagnosis, which is provided by the bone marrow biopsy.
*Fluorescence in situ hybridization analysis with 12:21 translocation*
- The **t(12;21) [ETV6-RUNX1] translocation** is the most common cytogenetic abnormality in childhood B-cell ALL (20-25% of cases) and is associated with favorable prognosis.
- While its presence is relevant for risk stratification and treatment planning, the primary diagnostic criterion for ALL is the **percentage of lymphoblasts in the bone marrow**.
Question 128: A 10-year-old boy is brought by his mother to his pediatrician for "skin growths." His mother reports that she started noticing small lumps arising from the patient's lips and eyelids several months ago. She also notes that he seems to suffer from frequent constipation and appears "weaker" than many of his peers. The boy's past medical history is unremarkable. His father and paternal grandmother have a history of medullary thyroid carcinoma. His height and weight are in the 85th and 45th percentiles, respectively. His temperature is 99°F (37.1°C), blood pressure is 110/65 mmHg, pulse is 90/min, and respirations are 18/min. On examination, he has an elongated face with protruding lips. There are numerous sessile painless nodules on the patient's lips, tongue, and eyelids. This patient's condition is most strongly associated with a mutation in which of the following genes?
A. NF1
B. MEN1
C. RET (Correct Answer)
D. NF2
E. c-KIT
Explanation: ***RET***
- The constellation of **skin growths** on the lips and eyelids (neuromas), **constipation** (ganglioneuromatosis), and a family history of **medullary thyroid carcinoma** (MTC) strongly suggests **Multiple Endocrine Neoplasia type 2B (MEN2B)**.
- MEN2B is caused by a germline mutation in the **RET proto-oncogene**, which is a receptor tyrosine kinase involved in cell growth and differentiation.
*NF1*
- Mutations in the **NF1 gene** cause **Neurofibromatosis type 1**, characterized by **café-au-lait spots**, neurofibromas (subcutaneous, not typically mucosal), iris Lisch nodules, and optic pathway gliomas.
- While it involves skin growths (neurofibromas), the specific mucosal neuromas, elongated facies, and family history of MTC are not typical features.
*MEN1*
- **MEN1 syndrome** is caused by mutations in the **MEN1 gene** and is associated with tumors of the **parathyroid**, **anterior pituitary**, and **pancreatic islet cells** (the 3 Ps).
- This patient's presentation of mucosal neuromas and medullary thyroid carcinoma is not characteristic of MEN1.
*NF2*
- Mutations in the **NF2 gene** cause **Neurofibromatosis type 2**, classically characterized by **bilateral vestibular schwannomas**, meningiomas, and ependymomas.
- Skin manifestations are less prominent and different from what is described, and MTC is not associated.
*c-KIT*
- Mutations in the **c-KIT gene** are primarily associated with **gastrointestinal stromal tumors (GIST)** and certain types of mastocytosis.
- It is not linked to the constellation of mucosal neuromas, elongated facies, or medullary thyroid carcinoma seen in this patient.
Question 129: A 55-year-old man presents to the emergency department because of an excruciating headache that started suddenly after he got home from work. He also reports having double vision. Specifically, in the last week he almost got into two car accidents with vehicles that "came out of nowhere" while he was trying to merge on the highway. Physical examination is notable for ptosis of the left eye, which is also inferiorly and laterally deviated. The patient is treated emergently and then started on a hormone replacement in order to avoid life-threatening post-treatment complications. The patient's current presentation was associated with a pathologic process that existed for several months prior to this event. Which of the following symptoms could this patient have experienced as part of that pre-existing pathology?
A. Kidney stones
B. Hyperkalemia
C. Increased hat size (Correct Answer)
D. Gastric ulcers
E. Hypoglycemia
Explanation: ***Increased hat size***
- The emergent treatment and subsequent hormone replacement for a life-threatening post-treatment complication, along with double vision and an excruciating headache, suggests a diagnosis of **pituitary apoplexy**.
- Pituitary apoplexy is often due to an acute hemorrhage or infarction within a pre-existing pituitary adenoma. A large adenoma can cause symptoms like **increased hat size** due to the progressive growth of facial bones and skull, a hallmark of **acromegaly** if the adenoma secretes growth hormone.
*Kidney stones*
- While a pituitary adenoma secreting **ACTH** (Cushing's disease) can lead to **hypercalciuria** and kidney stones, this specific symptom is not as directly indicative of a pre-existing pathology that would explain the acute presentation and subsequent hormone replacement.
- Kidney stones are not a primary or direct symptom of a pituitary adenoma in the way that acromegaly-related changes are.
*Hyperkalemia*
- Hyperkalemia is typically associated with conditions like **adrenal insufficiency** or **renal failure**, not directly with the pre-existing pituitary pathology leading to apoplexy.
- Insufficiency of mineralocorticoids (e.g., in adrenal crisis, which can be a complication of pituitary apoplexy due to ACTH deficiency) causes **hyponatremia** and **hyperkalemia**, but this would be a consequence of the acute event and not a pre-existing symptom of the adenoma itself.
*Gastric ulcers*
- Although conditions like **Zollinger-Ellison syndrome** (due to a **gastrinoma**) involve ulcers, and **MEN1 syndrome** can include pituitary adenomas and gastrinomas, gastric ulcers are not a direct or common pre-existing symptom of a pituitary adenoma itself.
- Additionally, **Cushing's syndrome** (which can be caused by an ACTH-secreting pituitary adenoma) can be associated with an increased risk of peptic ulcers due to high cortisol levels, but it's not a primary or specific finding.
*Hypoglycemia*
- Hypoglycemia can occur with **adrenal insufficiency** or **growth hormone deficiency**, both of which can be consequences of pituitary dysfunction, particularly if the adenoma destroys normal pituitary tissue or after apoplexy.
- However, hypoglycemia is often an acute or late symptom of hormonal deficiencies, rather than a prominent pre-existing symptom of the growing adenoma prior to the acute event, especially compared to the chronic changes of acromegaly.
Question 130: A 3-year-old boy was brought in by his parents for undescended testes. The physical examination showed an absence of the left testis in the scrotum. Inguinal swelling was noted on the left side and was surgically corrected. Which of the following conditions will most likely occur in the later stages of his life?
A. Epididymitis
B. Testicular cancer (Correct Answer)
C. Varicocele
D. Torsion testis
E. Spermatocele
Explanation: ***Testicular cancer***
- Undescended testes (**cryptorchidism**) are a major risk factor for developing **testicular cancer**, even after surgical correction (**orchidopexy**).
- The risk is higher for both the undescended and the contralateral descended testicle, suggesting a potential underlying developmental abnormality.
*Epididymitis*
- **Epididymitis** is an inflammation of the **epididymis**, usually caused by bacterial infection, and is not a common long-term complication of surgically corrected undescended testes.
- While it can cause scrotal pain and swelling, it is not directly linked to the history of cryptorchidism in this context.
*Varicocele*
- A **varicocele** is an enlargement of veins within the **spermatic cord**, often compared to a "bag of worms," and is a common cause of **male infertility**.
- It is not typically associated with a history of undescended testes, and its development is independent of whether the testis was surgically brought into the scrotum.
*Torsion testis*
- **Testicular torsion** is a surgical emergency involving the twisting of the **spermatic cord**, which cuts off the blood supply to the testicle.
- While it can occur in individuals with undescended testes, surgical correction does not significantly increase the lifetime risk beyond the general population, and it is a sudden event rather than a long-term consequence.
*Spermatocele*
- A **spermatocele** is a benign, sperm-containing cyst that develops in the **epididymis**, usually causing a painless lump above the testicle.
- These cysts are generally not a long-term complication of undescended testes or their surgical correction.
