Endocrine Pathology — MCQs

A 5-year-old boy has developed features suggestive of precocious puberty over the past 6 months. On physical examination, the boy exhibits secondary sex characteristics, including pubic hair and penile enlargement. Which of the following morphologic features is most likely to be observed in his adrenal glands?

Q44Easy

What is true about adrenal pheochromocytoma?

Q45Medium

A 34-year-old patient presents with a thyroid nodule. Ultrasonography shows foci of calcification. Based on typical histological features, what is the likely diagnosis?

Q46Easy

Acinic cell tumor is most commonly seen in which of the following locations?

Q47Easy

Which of the following are features of diffuse sclerosing variant of papillary carcinoma?

Q48Medium

A 40-year-old female presents with fever, fatigue, and diffuse painful swelling in the midline of the neck. Fine-needle aspiration cytology (FNAC) of the swelling reveals epithelioid cells and giant cells. What is the most likely diagnosis?

Q49Medium

A boy presented with hypertension is found to have pheochromocytoma. All of the following are true about pheochromocytoma, EXCEPT:

Q50Easy

"Orphan Annie nuclei" are seen in which of the following conditions?

Endocrine Pathology Indian Medical PG Practice Questions and MCQs

Question 41: Which of the following thyroid abnormalities is associated with IgG4-related disease?

A. De Quervain thyroiditis
B. Postpartum thyroiditis
C. Riedel thyroiditis (Correct Answer)
D. Hashimoto thyroiditis

Explanation: **Explanation:** **Riedel Thyroiditis** is the correct answer because it is now recognized as a manifestation of **IgG4-related systemic disease** [1]. It is characterized by dense, "rock-hard" fibrous replacement of the thyroid parenchyma, which often extends beyond the thyroid capsule into adjacent neck structures (muscles, trachea, and nerves) [1]. Histologically, it shows a dense inflammatory infiltrate rich in **IgG4-positive plasma cells** and storiform fibrosis [1]. **Analysis of Incorrect Options:** * **De Quervain Thyroiditis (Subacute Granulomatous):** This is a self-limiting, painful condition typically following a **viral upper respiratory infection**. It is characterized by granulomatous inflammation and multinucleated giant cells, not IgG4-related fibrosis [1]. * **Postpartum Thyroiditis:** This is a variant of silent (painless) lymphocytic thyroiditis occurring within one year of delivery. It is autoimmune in nature but lacks the fibro-inflammatory features of IgG4 disease. * **Hashimoto Thyroiditis:** While Hashimoto’s involves autoimmune destruction (anti-TPO/anti-Tg antibodies) and Hurthle cell changes, it is not primarily an IgG4-related disease. *Note: A rare "fibrosing variant" of Hashimoto exists, but Riedel is the classic association.* **High-Yield Clinical Pearls for NEET-PG:** * **Clinical Presentation:** Riedel thyroiditis presents as a **painless, fixed, "stony hard" neck mass** that can mimic thyroid carcinoma [1]. * **Complications:** Compression of the esophagus (dysphagia), trachea (stridor), and recurrent laryngeal nerve (hoarseness). * **Systemic Associations:** Patients often have other fibro-inflammatory conditions like **retroperitoneal fibrosis**, sclerosing cholangitis, or mediastinal fibrosis [1]. * **Treatment:** Steroids and Tamoxifen are often used to manage the fibrosis. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Endocrine System, pp. 1091-1092.

Question 42: What is the most common site for a pheochromocytoma?

A. Adrenal medulla (Correct Answer)
B. Adrenal cortex
C. Paravertebral ganglion
D. Paraaortic-sympathetic chain

Explanation: **Explanation:** **1. Why the Adrenal Medulla is Correct:** Pheochromocytoma is a catecholamine-secreting tumor derived from **chromaffin cells**. These cells are embryologically derived from the neural crest and are primarily concentrated in the **adrenal medulla** [1]. Statistically, approximately **85% to 90%** of these tumors occur within the adrenal medulla, making it the most common site. **2. Why the Other Options are Incorrect:** * **Adrenal Cortex:** This is the outer layer of the adrenal gland derived from mesoderm. it produces steroids (cortisol, aldosterone, androgens). It does not contain chromaffin cells and therefore cannot be the site of a pheochromocytoma. * **Paravertebral Ganglion & Paraaortic-sympathetic Chain:** While these are common sites for **extra-adrenal** pheochromocytomas (also known as **paragangliomas**), they only account for about 10-15% of cases. The most famous extra-adrenal site is the Organ of Zuckerkandl, located at the bifurcation of the aorta. **3. High-Yield Clinical Pearls for NEET-PG:** * **The Rule of 10s:** Traditionally, pheochromocytoma is known as the "10% tumor": 10% are extra-adrenal, 10% are bilateral, 10% are malignant, 10% occur in children, and 10% are not associated with hypertension. (Note: Recent genetics suggest up to 25-30% may be familial). * **Zellballen Pattern:** On histology, the tumor cells are arranged in small clusters or nests surrounded by a rich vascular network. * **Diagnosis:** The best initial screening test is measuring **urinary or plasma metanephrines** (metabolites of catecholamines). * **Associated Syndromes:** MEN 2A, MEN 2B, von Hippel-Lindau (VHL) syndrome, and Neurofibromatosis type 1 (NF1). **References:** [1] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Liver And Biliary System Disease, pp. 418-419.

Question 43: A 5-year-old boy has developed features suggestive of precocious puberty over the past 6 months. On physical examination, the boy exhibits secondary sex characteristics, including pubic hair and penile enlargement. Which of the following morphologic features is most likely to be observed in his adrenal glands?

A. Cortical atrophy
B. Cortical hyperplasia (Correct Answer)
C. Cortical nodule
D. Medullary atrophy

Explanation: The clinical presentation of precocious puberty in a 5-year-old boy, characterized by secondary sex characteristics (pubic hair, penile enlargement) without testicular enlargement, is highly suggestive of **Congenital Adrenal Hyperplasia (CAH)** [1]. **1. Why Cortical Hyperplasia is Correct:** CAH is most commonly caused by a deficiency in the enzyme **21-hydroxylase**. This enzymatic block prevents the synthesis of cortisol, leading to a lack of negative feedback on the pituitary gland. Consequently, there is a compensatory increase in **ACTH (Adrenocorticotropic Hormone)** secretion [1]. Chronic elevation of ACTH overstimulates the adrenal cortex, resulting in **bilateral cortical hyperplasia**. The shunting of steroid precursors into the androgenic pathway leads to excessive testosterone production, causing the observed precocious puberty [1]. **2. Why Other Options are Incorrect:** * **Cortical Atrophy:** This occurs in Addison’s disease (autoimmune destruction) or exogenous steroid use (suppression of ACTH). It would result in a deficiency of androgens, not an excess. * **Cortical Nodule:** While a functional adrenal adenoma could cause hormone excess, CAH (the most common cause of such systemic features in a child) typically presents with diffuse hyperplasia due to the systemic drive of ACTH. * **Medullary Atrophy:** The adrenal medulla (producing catecholamines) is embryologically and functionally distinct from the cortex and is not affected by the ACTH-cortisol feedback loop. **Clinical Pearls for NEET-PG:** * **Most common cause of CAH:** 21-hydroxylase deficiency (90-95% of cases). * **Biochemical Marker:** Elevated levels of **17-hydroxyprogesterone**. * **Key Distinction:** In boys with CAH, the penis is enlarged but the **testes are small/pre-pubertal** (pseudoprecocious puberty). If the testes were large, it would suggest a central (GnRH-dependent) cause. * **Morphology:** Adrenals in CAH are typically "brown" due to lipid depletion and show a "wrinkled" cerebriform appearance. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Endocrine System, pp. 1130-1131.

Question 44: What is true about adrenal pheochromocytoma?

A. Chromaffin negative
B. Mostly malignant
C. Bilateral in 10 percent of cases (Correct Answer)
D. Unilateral in 10 percent of cases

Explanation: **Explanation:** Pheochromocytoma is a catecholamine-secreting tumor arising from the chromaffin cells of the adrenal medulla [3], [4]. It is famously known as the **"10% Tumor"** because of its consistent clinical patterns. **1. Why Option C is Correct:** The "Rule of 10s" is the hallmark of Pheochromocytoma. Approximately **10% of cases are bilateral**, particularly when associated with familial syndromes like MEN 2A, MEN 2B, von Hippel-Lindau (VHL), and NF-1 [1]. In sporadic cases, the tumor is typically unilateral. **2. Why the Other Options are Incorrect:** * **Option A (Chromaffin negative):** Incorrect. These tumors are derived from **chromaffin cells** (neural crest origin). They are **Chromaffin positive**, meaning they turn dark brown when treated with potassium dichromate salts due to the oxidation of stored catecholamines [3], [4]. * **Option B (Mostly malignant):** Incorrect. According to the Rule of 10s, only **10% are malignant** [4]. Malignancy is defined strictly by the presence of metastases (e.g., to lymph nodes, liver, or bone), not by histological appearance [4]. * **Option D (Unilateral in 10%):** Incorrect. The vast majority (**90%**) of sporadic pheochromocytomas are unilateral. **High-Yield Clinical Pearls for NEET-PG:** * **The Rule of 10s:** 10% Bilateral, 10% Malignant, 10% Extra-adrenal (called Paragangliomas), 10% Pediatric, and 10% Not associated with hypertension [2]. * **Zellballen Pattern:** Histology shows nests of cells (Zellballen) surrounded by a vascular stroma. * **Markers:** Positive for **Chromogranin A** and **Synaptophysin**. S-100 highlights the peripheral sustentacular cells. * **Diagnosis:** Best initial screening test is **Urinary/Plasma Metanephrines** (more sensitive than VMA). **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Endocrine System, p. 1137. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Endocrine System, pp. 1138-1139. [3] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Endocrine System, pp. 1137-1138. [4] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Liver And Biliary System Disease, pp. 419-420.

Question 45: A 34-year-old patient presents with a thyroid nodule. Ultrasonography shows foci of calcification. Based on typical histological features, what is the likely diagnosis?

A. Follicular carcinoma
B. Medullary carcinoma
C. Papillary carcinoma (Correct Answer)
D. Anaplastic carcinoma

Explanation: ### Explanation **Correct Answer: C. Papillary Carcinoma** The presence of calcification in a thyroid nodule, especially when seen as "psammoma bodies" on histology, is a hallmark feature of **Papillary Thyroid Carcinoma (PTC)** [1]. 1. **Why it is correct:** PTC is the most common thyroid malignancy. Histologically, it is characterized by papillary projections and distinctive nuclear features (Orphan Annie eye nuclei, nuclear grooves, and pseudoinclusions) [1],[3]. A key diagnostic feature is the presence of **Psammoma bodies**, which are concentric, laminated calcifications found within the papillae [1]. On ultrasonography, these appear as punctate microcalcifications. 2. **Why other options are incorrect:** * **Follicular Carcinoma:** Characterized by capsular or vascular invasion [4]. It typically lacks psammoma bodies and presents as a cold nodule with a follicular pattern [4]. * **Medullary Carcinoma:** Derived from parafollicular C-cells [3]. While it can show calcification, it is typically associated with **amyloid stroma** (staining with Congo Red). * **Anaplastic Carcinoma:** A highly aggressive tumor in elderly patients [3]. It shows pleomorphic cells and rapid growth but is not typically characterized by the organized microcalcifications seen in PTC. **High-Yield Clinical Pearls for NEET-PG:** * **Most common** thyroid cancer: Papillary Carcinoma (best prognosis) [1],[3]. * **Risk factor:** Prior exposure to ionizing radiation. * **Genetic markers:** *BRAF* mutations (most common) and *RET/PTC* rearrangements [2]. * **Psammoma bodies** are also found in: **M**eningioma, **P**apillary serous cystadenocarcinoma of the ovary, and **M**esothelioma (Mnemonic: **PS**a**MM**oma). * **Lymphatic spread** is common in PTC, whereas Follicular Carcinoma spreads hematogenously [3]. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Endocrine System, p. 1099. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Endocrine System, pp. 1099-1100. [3] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Liver And Biliary System Disease, pp. 429-430. [4] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Endocrine System, pp. 1100-1101.

Question 46: Acinic cell tumor is most commonly seen in which of the following locations?

A. Parotid gland (Correct Answer)
B. Parathyroid
C. Sublingual gland
D. Thyroid

Explanation: ### Explanation **Acinic Cell Carcinoma (ACC)** is a malignant salivary gland tumor that demonstrates cytological differentiation toward serous acinar cells. **Why Parotid Gland is Correct:** The **parotid gland** is the most common site for Acinic Cell Carcinoma, accounting for approximately **80% of cases**. This is because the parotid is primarily composed of serous acini, and this tumor originates from the terminal duct or precursor cells that differentiate into serous cells containing characteristic zymogen-like granules. While it is generally considered a low-grade malignancy with a favorable prognosis, it is the second most common malignant salivary gland tumor in children (after Mucoepidermoid carcinoma) [1]. **Why Other Options are Incorrect:** * **Parathyroid & Thyroid:** These are endocrine glands. While they can develop various adenomas or carcinomas (e.g., Papillary or Follicular thyroid cancer), "Acinic cell tumor" is a specific histopathological entity exclusive to salivary tissues. * **Sublingual Gland:** Although salivary gland tumors can occur here, the sublingual gland is a rare site for any neoplasm. When tumors do occur in minor salivary glands or the sublingual gland, they are more likely to be Adenoid Cystic Carcinoma or Mucoepidermoid Carcinoma [1]. **High-Yield Clinical Pearls for NEET-PG:** * **Histology:** Look for "clear cells" or cells with **basophilic, granular cytoplasm** (resembling normal serous acini). * **Staining:** The granules are **PAS-positive** and diastase-resistant. * **Bilateralism:** Acinic cell carcinoma is the most common salivary gland malignancy to occur **bilaterally** (though still rare overall). * **Demographics:** It shows a slight female predilection and occurs across a wide age range, including pediatric populations. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Head and Neck, pp. 753-755.

Question 47: Which of the following are features of diffuse sclerosing variant of papillary carcinoma?

A. Occurs in young individuals including children
B. Extensive fibrosis throughout the gland
C. Associated with lymphocytic infiltrate
D. All of the above (Correct Answer)

Explanation: The **Diffuse Sclerosing Variant (DSV)** is a distinct and aggressive subtype of Papillary Thyroid Carcinoma (PTC). Understanding its unique clinicopathological profile is crucial for NEET-PG. ### **Explanation of Options:** * **Option A (Young individuals):** Unlike the classic variant, DSV typically presents in **younger patients**, frequently involving children and adolescents [1]. It often presents as a diffuse, painless enlargement of the thyroid gland rather than a solitary nodule. * **Option B (Extensive fibrosis):** As the name "sclerosing" suggests, the hallmark of this variant is **marked stromal fibrosis** that extends throughout the thyroid lobe or the entire gland [1]. This often gives the gland a firm, hard consistency on palpation. * **Option C (Lymphocytic infiltrate):** Histologically, DSV is characterized by a prominent **background of chronic lymphocytic thyroiditis** (resembling Hashimoto’s) [1]. This is accompanied by numerous **Psammoma bodies** (often more abundant than in classic PTC) and squamous metaplasia [1]. Since all three features are characteristic of this variant, **Option D** is the correct answer. ### **High-Yield Clinical Pearls for NEET-PG:** * **Imaging:** On ultrasound or X-ray, it may show "snowstorm" calcifications due to the abundance of Psammoma bodies. * **Spread:** It has a higher incidence of **lymph node metastasis** (often bilateral) and **distant metastasis** (especially to the lungs) compared to classic PTC. * **Molecular Profile:** It is frequently associated with **RET/PTC rearrangements** rather than BRAF mutations. * **Prognosis:** Despite its aggressive presentation and higher stage at diagnosis, the overall survival remains relatively good, though the recurrence rate is higher than classic PTC. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Endocrine System, p. 1099.

Question 48: A 40-year-old female presents with fever, fatigue, and diffuse painful swelling in the midline of the neck. Fine-needle aspiration cytology (FNAC) of the swelling reveals epithelioid cells and giant cells. What is the most likely diagnosis?

A. Acute thyroiditis
B. Subacute thyroiditis (Correct Answer)
C. Tubercular lymphadenitis
D. Hashimoto's thyroiditis

Explanation: ### **Explanation** The clinical presentation of a **painful, tender thyroid swelling** following a viral prodrome (fever, fatigue) is the classic hallmark of **Subacute Thyroiditis** (also known as De Quervain’s or Granulomatous Thyroiditis). **1. Why Subacute Thyroiditis is correct:** The diagnosis is confirmed by the FNAC findings of **epithelioid cells and multinucleated giant cells**, which represent the granulomatous inflammatory response to damaged thyroid follicles. This condition is typically triggered by a viral infection (e.g., Coxsackievirus, Mumps) and is the most common cause of a painful thyroid gland. [1] **2. Why the other options are incorrect:** * **Acute Thyroiditis:** Usually caused by a bacterial infection (e.g., *S. aureus*). While it presents with pain and fever, the cytology would show **neutrophils and abscess formation**, not granulomatous inflammation. * **Tubercular Lymphadenitis:** While it shows epithelioid granulomas and giant cells, it typically involves the **lateral cervical lymph nodes**, not a diffuse midline thyroid swelling. Primary tuberculosis of the thyroid is extremely rare. * **Hashimoto’s Thyroiditis:** This is a **painless** goiter. FNAC would reveal a dense lymphocytic infiltrate, germinal centers, and characteristic **Hürthle cells** (oncocytes), but not granulomas. [1] **3. NEET-PG High-Yield Pearls:** * **Etiology:** Post-viral; associated with **HLA-B35**. * **Clinical Phase:** Often follows a triphasic course: Hyperthyroidism (leakage of T3/T4) → Hypothyroidism → Recovery. [1] * **Lab Marker:** Characteristically high **ESR** with **low radioactive iodine uptake (RAIU)** due to follicular damage. [1] * **Treatment:** Self-limiting; managed with NSAIDs or corticosteroids for pain. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Endocrine System, pp. 1089-1092.

Question 49: A boy presented with hypertension is found to have pheochromocytoma. All of the following are true about pheochromocytoma, EXCEPT:

A. Benign in nature
B. Malignant tumor (Correct Answer)
C. Secretes hormones
D. Hypertension is seen

Explanation: Pheochromocytoma is a catecholamine-secreting tumor arising from the chromaffin cells of the adrenal medulla [1]. **Why "Malignant tumor" is the correct (Except) option:** The vast majority of pheochromocytomas (approximately **90%**) are **benign** [1]. Only about 10% are malignant. Therefore, characterizing the tumor generally as a "malignant tumor" is factually incorrect. In pathology, malignancy in pheochromocytoma is strictly defined by the presence of **metastases** (to non-chromaffin sites like bone, liver, or lymph nodes) rather than local invasion or cellular atypia [1]. **Analysis of other options:** * **A. Benign in nature:** This is true for 90% of cases [1]. Most patients are cured by surgical resection. * **C. Secretes hormones:** This is true. These tumors secrete catecholamines (epinephrine and norepinephrine), which are responsible for the clinical symptoms [3]. * **D. Hypertension is seen:** This is the most common clinical sign [3]. It can be persistent or paroxysmal (spells), often accompanied by the classic triad of headache, sweating, and palpitations [3]. **High-Yield NEET-PG Pearls:** * **The Rule of 10s:** 10% are malignant, 10% are bilateral, 10% are extra-adrenal (Paragangliomas), and 10% occur in children. * **Zellballen Pattern:** Histology typically shows nests of cells surrounded by a vascular stroma [1]. * **Diagnosis:** Best initial screening test is **24-hour urinary fractionated metanephrines** or plasma free metanephrines. * **Genetic Associations:** Frequently associated with **MEN 2A and 2B**, Von Hippel-Lindau (VHL) syndrome, and NF-1 [2]. * **Management:** Always give **alpha-blockers (e.g., Phenoxybenzamine)** before beta-blockers to avoid a hypertensive crisis. **References:** [1] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Liver And Biliary System Disease, pp. 419-420. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Endocrine System, p. 1137. [3] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Endocrine System, pp. 1138-1139.

Question 50: "Orphan Annie nuclei" are seen in which of the following conditions?

A. Medullary carcinoma of thyroid
B. Anaplastic carcinoma of thyroid
C. Papillary carcinoma of thyroid (Correct Answer)
D. Follicular carcinoma of thyroid

Explanation: **Explanation:** **Papillary Carcinoma of Thyroid (PTC)** is the most common thyroid malignancy [1]. The diagnosis is primarily based on characteristic nuclear features rather than architectural patterns. **"Orphan Annie eye" nuclei** refer to large, overlapping nuclei with finely dispersed chromatin that appears optically clear or empty on H&E staining [1], [2]. This appearance is an artifact of fixation [1]. **Why the other options are incorrect:** * **Medullary Carcinoma:** Derived from parafollicular C-cells. It is characterized by nests of cells in an amyloid-rich stroma [2]. It is associated with *RET* mutations and MEN 2A/2B syndromes. * **Anaplastic Carcinoma:** A highly aggressive, undifferentiated tumor seen in older patients [2]. It shows pleomorphic giant cells or spindle cells but lacks the specific nuclear features of PTC. * **Follicular Carcinoma:** Defined by capsular or vascular invasion [2]. The nuclei typically resemble normal follicular cells and do not show clearing or grooves [1]. **High-Yield Clinical Pearls for NEET-PG:** 1. **Other Nuclear Features of PTC:** Besides Orphan Annie nuclei, look for **Nuclear Grooves** (coffee bean appearance) and **Intranuclear Cytoplasmic Inclusions** (Pseudo-inclusions) [1]. 2. **Psammoma Bodies:** These are laminated calcifications frequently seen in the stroma of Papillary Carcinoma (rare in other thyroid cancers). 3. **Genetics:** PTC is associated with **BRAF mutations** (most common) and **RET/PTC rearrangements**. 4. **Prognosis:** It has an excellent prognosis and typically spreads via the **lymphatics** to cervical lymph nodes [2]. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Endocrine System, pp. 1098-1099. [2] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Liver And Biliary System Disease, pp. 429-430.

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