Akademik Veri Yönetim Sistemi
INDIAN JOURNAL OF CANCER, cilt.60, sa.4, ss.556-561, 2023 (SCI-Expanded, Scopus)
Purpose:Concurrence of medullary and papillary thyroid carcinoma (MTC and PTC) represents less than 1% of all thyroid malignancies. We aimed to reveal the demographic and clinical characteristics of this rare pathology and to evaluate the effect of the same or contralateral lobular localization of these two malignancies in clinical and laboratory features. Evaluation of progression-free survival (PFS) in current pathology is one of the important features of our study.All patients diagnosed with simultaneous MTC and PTC after thyroidectomy were evaluated retrospectively. Data on the following variables were recorded: age, gender, tumor localization (ipsilateral lobe located MTC and PTC-Group I, contralateral lobe located MTC and PTC-Group II), tumor size, cervical lymph node metastasis, distant metastasis, tumor stage, postoperative basal calcitonin, carcinoembryonic antigen, thyroglobulin (Tg), and anti-Tg values. In all our cases, since MTC progressed before PTC, progression was accepted as serum calcitonin values exceeded 150 pg/mL.Groups were formed as follows: Group I, four cases where MTC and PTC were localized in different foci in the same lobe; Group II, nine cases where they were localized in different lobes. There was only one case in which two tumors were located in the same focus. The case with dual differentiation was included in Group I (35. 7%). When the PFS of the two groups were compared, no statistically significant difference was found (P = 0.87).As a result of this analysis, the location of the simultaneously detected PTC in the same or different lobes with the MTC does not make a significant difference in clinical and laboratory features.Papillary thyroid cancer (PTC) is the most common histological subtype of thyroid cancer, accounting for 75-80% of all thyroid cancer cases.[1] It originates from follicular cells from the foregut endoderm and produces thyroglobulin (Tg), and thyroid hormones. Medullary thyroid cancer (MTC) accounts for 5-8% of all thyroid cancer cases.[2] It originates from the fourth brachial arch neuroectoderm parafollicular cells, secretes hormonal peptide and calcitonin, and is considered a member of the amine precursor uptake and decarboxylation system. It can also be seen as hereditary or nonhereditary. Hereditary cases appear in the clinic as familial MTC (fMTC) or multiple endocrine neoplasia type 2. The prognoses for these thyroid cancer types are worse than they are for cases of PTC.PTC and MTC are distinct types of thyroid carcinomas with significantly different histology, incidence, cellular origin, and histopathological features. Synchronous occurrence of these two carcinomas is uncommon. The first cases of these carcinomas were described by Lamberg in 1981.[3] The concurrence of medullary and papillary carcinomas represents less than 1% of all thyroid malignancies.[4]Concurrent medullary and follicular cell-derived carcinomas can be divided into three categories: i) synchronous tumors located in different anatomical positions; ii) collision tumors located on each other's borders; iii) true mixed tumors in the same focus. Nonetheless, it remains unclear whether these tumors develop from the same embryogenic origin or are detected incidentally.In 1988, the World Health Organization (WHO) defined the presence of medullary and follicular morphological appearance, immunoreactive calcitonin, and Tg in the same primary tumor as "mixed medullary and follicular thyroid carcinoma". This rare malignancy accounts for less than 1% of all thyroid cancers. [4] Furthermore, this definition does not classify follicular cells as follicular, papillary, poorly differentiated, or anaplastic. According to the WHO, the medullary component determines the prognosis in mixed cases.[5]Purpose:Concurrence of medullary and papillary thyroid carcinoma (MTC and PTC) represents less than 1% of all thyroid malignancies. We aimed to reveal the demographic and clinical characteristics of this rare pathology and to evaluate the effect of the same or contralateral lobular localization of these two malignancies in clinical and laboratory features. Evaluation of progression-free survival (PFS) in current pathology is one of the important features of our study.All patients diagnosed with simultaneous MTC and PTC after thyroidectomy were evaluated retrospectively. Data on the following variables were recorded: age, gender, tumor localization (ipsilateral lobe located MTC and PTC-Group I, contralateral lobe located MTC and PTC-Group II), tumor size, cervical lymph node metastasis, distant metastasis, tumor stage, postoperative basal calcitonin, carcinoembryonic antigen, thyroglobulin (Tg), and anti-Tg values. In all our cases, since MTC progressed before PTC, progression was accepted as serum calcitonin values exceeded 150 pg/mL.Groups were formed as follows: Group I, four cases where MTC and PTC were localized in different foci in the same lobe; Group II, nine cases where they were localized in different lobes. There was only one case in which two tumors were located in the same focus. The case with dual differentiation was included in Group I (35. 7%). When the PFS of the two groups were compared, no statistically significant difference was found (P = 0.87).As a result of this analysis, the location of the simultaneously detected PTC in the same or different lobes with the MTC does not make a significant difference in clinical and laboratory features.Papillary thyroid cancer (PTC) is the most common histological subtype of thyroid cancer, accounting for 75-80% of all thyroid cancer cases.[1] It originates from follicular cells from the foregut endoderm and produces thyroglobulin (Tg), and thyroid hormones. Medullary thyroid cancer (MTC) accounts for 5-8% of all thyroid cancer cases.[2] It originates from the fourth brachial arch neuroectoderm parafollicular cells, secretes hormonal peptide and calcitonin, and is considered a member of the amine precursor uptake and decarboxylation system. It can also be seen as hereditary or nonhereditary. Hereditary cases appear in the clinic as familial MTC (fMTC) or multiple endocrine neoplasia type 2. The prognoses for these thyroid cancer types are worse than they are for cases of PTC.PTC and MTC are distinct types of thyroid carcinomas with significantly different histology, incidence, cellular origin, and histopathological features. Synchronous occurrence of these two carcinomas is uncommon. The first cases of these carcinomas were described by Lamberg in 1981.[3] The concurrence of medullary and papillary carcinomas represents less than 1% of all thyroid malignancies.[4]Concurrent medullary and follicular cell-derived carcinomas can be divided into three categories: i) synchronous tumors located in different anatomical positions; ii) collision tumors located on each other's borders; iii) true mixed tumors in the same focus. Nonetheless, it remains unclear whether these tumors develop from the same embryogenic origin or are detected incidentally. In 1988, the World Health Organization (WHO) defined the presence of medullary and follicular morphological appearance, immunoreactive calcitonin, and Tg in the same primary tumor as "mixed medullary and follicular thyroid carcinoma". This rare malignancy accounts for less than 1% of all thyroid cancers.[4] Furthermore, this definition does not classify follicular cells as follicular, papillary, poorly differentiated, or anaplastic. According to the WHO, the medullary component determines the prognosis in mixed cases.[5]Purpose:Concurrence of medullary and papillary thyroid carcinoma (MTC and PTC) represents less than 1% of all thyroid malignancies. We aimed to reveal the demographic and clinical characteristics of this rare pathology and to evaluate the effect of the same or contralateral lobular localization of these two malignancies in clinical and laboratory features. Evaluation of progression-free survival (PFS) in current pathology is one of the important features of our study.All patients diagnosed with simultaneous MTC and PTC after thyroidectomy were evaluated retrospectively. Data on the following variables were recorded: age, gender, tumor localization (ipsilateral lobe located MTC and PTC-Group I, contralateral lobe located MTC and PTC-Group II), tumor size, cervical lymph node metastasis, distant metastasis, tumor stage, postoperative basal calcitonin, carcinoembryonic antigen, thyroglobulin (Tg), and anti-Tg values. In all our cases, since MTC progressed before PTC, progression was accepted as serum calcitonin values exceeded 150 pg/mL.Groups were formed as follows: Group I, four cases where MTC and PTC were localized in different foci in the same lobe; Group II, nine cases where they were localized in different lobes. There was only one case in which two tumors were located in the same focus. The case with dual differentiation was included in Group I (35. 7%). When the PFS of the two groups were compared, no statistically significant difference was found (P = 0.87).As a result of this analysis, the location of the simultaneously detected PTC in the same or different lobes with the MTC does not make a significant difference in clinical and laboratory features.Papillary thyroid cancer (PTC) is the most common histological subtype of thyroid cancer, accounting for 75-80% of all thyroid cancer cases.[1] It originates from follicular cells from the foregut endoderm and produces thyroglobulin (Tg), and thyroid hormones. Medullary thyroid cancer (MTC) accounts for 5-8% of all thyroid cancer cases.[2] It originates from the fourth brachial arch neuroectoderm parafollicular cells, secretes hormonal peptide and calcitonin, and is considered a member of the amine precursor uptake and decarboxylation system. It can also be seen as hereditary or nonhereditary. Hereditary cases appear in the clinic as familial MTC (fMTC) or multiple endocrine neoplasia type 2. The prognoses for these thyroid cancer types are worse than they are for cases of PTC.PTC and MTC are distinct types of thyroid carcinomas with significantly different histology, incidence, cellular origin, and histopathological features. Synchronous occurrence of these two carcinomas is uncommon. The first cases of these carcinomas were described by Lamberg in 1981.[3] The concurrence of medullary and papillary carcinomas represents less than 1% of all thyroid malignancies. [4]Concurrent medullary and follicular cell-derived carcinomas can be divided into three categories: i) synchronous tumors located in different anatomical positions; ii) collision tumors located on each other's borders; iii) true mixed tumors in the same focus. Nonetheless, it remains unclear whether these tumors develop from the same embryogenic origin or are detected incidentally.In 1988, the World Health Organization (WHO) defined the presence of medullary and follicular morphological appearance, immunoreactive calcitonin, and Tg in the same primary tumor as "mixed medullary and follicular thyroid carcinoma". This rare malignancy accounts for less than 1% of all thyroid cancers.[4] Furthermore, this definition does not classify follicular cells as follicular, papillary, poorly differentiated, or anaplastic. According to the WHO, the medullary component determines the prognosis in mixed cases.[5]Purpose:Concurrence of medullary and papillary thyroid carcinoma (MTC and PTC) represents less than 1% of all thyroid malignancies. We aimed to reveal the demographic and clinical characteristics of this rare pathology and to evaluate the effect of the same or contralateral lobular localization of these two malignancies in clinical and laboratory features. Evaluation of progression-free survival (PFS) in current pathology is one of the important features of our study.All patients diagnosed with simultaneous MTC and PTC after thyroidectomy were evaluated retrospectively. Data on the following variables were recorded: age, gender, tumor localization (ipsilateral lobe located MTC and PTC-Group I, contralateral lobe located MTC and PTC-Group II), tumor size, cervical lymph node metastasis, distant metastasis, tumor stage, postoperative basal calcitonin, carcinoembryonic antigen, thyroglobulin (Tg), and anti-Tg values. In all our cases, since MTC progressed before PTC, progression was accepted as serum calcitonin values exceeded 150 pg/mL.Groups were formed as follows: Group I, four cases where MTC and PTC were localized in different foci in the same lobe; Group II, nine cases where they were localized in different lobes. There was only one case in which two tumors were located in the same focus. The case with dual differentiation was included in Group I (35. 7%). When the PFS of the two groups were compared, no statistically significant difference was found (P = 0.87).As a result of this analysis, the location of the simultaneously detected PTC in the same or different lobes with the MTC does not make a significant difference in clinical and laboratory features.Papillary thyroid cancer (PTC) is the most common histological subtype of thyroid cancer, accounting for 75-80% of all thyroid cancer cases.[1] It originates from follicular cells from the foregut endoderm and produces thyroglobulin (Tg), and thyroid hormones. Medullary thyroid cancer (MTC) accounts for 5-8% of all thyroid cancer cases.[2] It originates from the fourth brachial arch neuroectoderm parafollicular cells, secretes hormonal peptide and calcitonin, and is considered a member of the amine precursor uptake and decarboxylation system. It can also be seen as hereditary or nonhereditary. Hereditary cases appear in the clinic as familial MTC (fMTC) or multiple endocrine neoplasia type 2. The prognoses for these thyroid cancer types are worse than they are for cases of PTC.PTC and MTC are distinct types of thyroid carcinomas with significantly different histology, incidence, cellular origin, and histopathological features. Synchronous occurrence of these two carcinomas is uncommon. The first cases of these carcinomas were described by Lamberg in 1981.[3] The concurrence of medullary and papillary carcinomas represents less than 1% of all thyroid malignancies.[4]Concurrent medullary and follicular cell-derived carcinomas can be divided into three categories: i) synchronous tumors located in different anatomical positions; ii) collision tumors located on each other's borders; iii) true mixed tumors in the same focus. Nonetheless, it remains unclear whether these tumors develop from the same embryogenic origin or are detected incidentally.In 1988, the World Health Organization (WHO) defined the presence of medullary and follicular morphological appearance, immunoreactive calcitonin, and Tg in the same primary tumor as "mixed medullary and follicular thyroid carcinoma". This rare malignancy accounts for less than 1% of all thyroid cancers.[4] Furthermore, this definition does not classify follicular cells as follicular, papillary, poorly differentiated, or anaplastic. According to the WHO, the medullary component determines the prognosis in mixed cases.[5]Purpose:Concurrence of medullary and papillary thyroid carcinoma (MTC and PTC) represents less than 1% of all thyroid malignancies. We aimed to reveal the demographic and clinical characteristics of this rare pathology and to evaluate the effect of the same or contralateral lobular localization of these two malignancies in clinical and laboratory features. Evaluation of progression-free survival (PFS) in current pathology is one of the important features of our study.All patients diagnosed with simultaneous MTC and PTC after thyroidectomy were evaluated retrospectively. Data on the following variables were recorded: age, gender, tumor localization (ipsilateral lobe located MTC and PTC-Group I, contralateral lobe located MTC and PTC-Group II), tumor size, cervical lymph node metastasis, distant metastasis, tumor stage, postoperative basal calcitonin, carcinoembryonic antigen, thyroglobulin (Tg), and anti-Tg values. In all our cases, since MTC progressed before PTC, progression was accepted as serum calcitonin values exceeded 150 pg/mL.Groups were formed as follows: Group I, four cases where MTC and PTC were localized in different foci in the same lobe; Group II, nine cases where they were localized in different lobes. There was only one case in which two tumors were located in the same focus. The case with dual differentiation was included in Group I (35. 7%). When the PFS of the two groups were compared, no statistically significant difference was found (P = 0.87).As a result of this analysis, the location of the simultaneously detected PTC in the same or different lobes with the MTC does not make a significant difference in clinical and laboratory features.Papillary thyroid cancer (PTC) is the most common histological subtype of thyroid cancer, accounting for 75-80% of all thyroid cancer cases.[1] It originates from follicular cells from the foregut endoderm and produces thyroglobulin (Tg), and thyroid hormones. Medullary thyroid cancer (MTC) accounts for 5-8% of all thyroid cancer cases.[2] It originates from the fourth brachial arch neuroectoderm parafollicular cells, secretes hormonal peptide and calcitonin, and is considered a member of the amine precursor uptake and decarboxylation system. It can also be seen as hereditary or nonhereditary. Hereditary cases appear in the clinic as familial MTC (fMTC) or multiple endocrine neoplasia type 2. The prognoses for these thyroid cancer types are worse than they are for cases of PTC. PTC and MTC are distinct types of thyroid carcinomas with significantly different histology, incidence, cellular origin, and histopathological features. Synchronous occurrence of these two carcinomas is uncommon. The first cases of these carcinomas were described by Lamberg in 1981.[3] The concurrence of medullary and papillary carcinomas represents less than 1% of all thyroid malignancies.[4]Concurrent medullary and follicular cell-derived carcinomas can be divided into three categories: i) synchronous tumors located in different anatomical positions; ii) collision tumors located on each other's borders; iii) true mixed tumors in the same focus. Nonetheless, it remains unclear whether these tumors develop from the same embryogenic origin or are detected incidentally.In 1988, the World Health Organization (WHO) defined the presence of medullary and follicular morphological appearance, immunoreactive calcitonin, and Tg in the same primary tumor as "mixed medullary and follicular thyroid carcinoma". This rare malignancy accounts for less than 1% of all thyroid cancers.[4] Furthermore, this definition does not classify follicular cells as follicular, papillary, poorly differentiated, or anaplastic. According to the WHO, the medullary component determines the prognosis in mixed cases.[5]Purpose:Concurrence of medullary and papillary thyroid carcinoma (MTC and PTC) represents less than 1% of all thyroid malignancies. We aimed to reveal the demographic and clinical characteristics of this rare pathology and to evaluate the effect of the same or contralateral lobular localization of these two malignancies in clinical and laboratory features. Evaluation of progression-free survival (PFS) in current pathology is one of the important features of our study.All patients diagnosed with simultaneous MTC and PTC after thyroidectomy were evaluated retrospectively. Data on the following variables were recorded: age, gender, tumor localization (ipsilateral lobe located MTC and PTC-Group I, contralateral lobe located MTC and PTC-Group II), tumor size, cervical lymph node metastasis, distant metastasis, tumor stage, postoperative basal calcitonin, carcinoembryonic antigen, thyroglobulin (Tg), and anti-Tg values. In all our cases, since MTC progressed before PTC, progression was accepted as serum calcitonin values exceeded 150 pg/mL.Groups were formed as follows: Group I, four cases where MTC and PTC were localized in different foci in the same lobe; Group II, nine cases where they were localized in different lobes. There was only one case in which two tumors were located in the same focus. The case with dual differentiation was included in Group I (35. 7%). When the PFS of the two groups were compared, no statistically significant difference was found (P = 0.87).As a result of this analysis, the location of the simultaneously detected PTC in the same or different lobes with the MTC does not make a significant difference in clinical and laboratory features.Papillary thyroid cancer (PTC) is the most common histological subtype of thyroid cancer, accounting for 75-80% of all thyroid cancer cases.[1] It originates from follicular cells from the foregut endoderm and produces thyroglobulin (Tg), and thyroid hormones. Medullary thyroid cancer (MTC) accounts for 5-8% of all thyroid cancer cases.[2] It originates from the fourth brachial arch neuroectoderm parafollicular cells, secretes hormonal peptide and calcitonin, and is considered a member of the amine precursor uptake and decarboxylation system. It can also be seen as hereditary or nonhereditary. Hereditary cases appear in the clinic as familial MTC (fMTC) or multiple endocrine neoplasia type 2. The prognoses for these thyroid cancer types are worse than they are for cases of PTC.PTC and MTC are distinct types of thyroid carcinomas with significantly different histology, incidence, cellular origin, and histopathological features. Synchronous occurrence of these two carcinomas is uncommon. The first cases of these carcinomas were described by Lamberg in 1981.[3] The concurrence of medullary and papillary carcinomas represents less than 1% of all thyroid malignancies.[4]Concurrent medullary and follicular cell-derived carcinomas can be divided into three categories: i) synchronous tumors located in different anatomical positions; ii) collision tumors located on each other's borders; iii) true mixed tumors in the same focus. Nonetheless, it remains unclear whether these tumors develop from the same embryogenic origin or are detected incidentally.In 1988, the World Health Organization (WHO) defined the presence of medullary and follicular morphological appearance, immunoreactive calcitonin, and Tg in the same primary tumor as "mixed medullary and follicular thyroid carcinoma". This rare malignancy accounts for less than 1% of all thyroid cancers.[4] Furthermore, this definition does not classify follicular cells as follicular, papillary, poorly differentiated, or anaplastic. According to the WHO, the medullary component determines the prognosis in mixed cases.[5]Purpose:Concurrence of medullary and papillary thyroid carcinoma (MTC and PTC) represents less than 1% of all thyroid malignancies. We aimed to reveal the demographic and clinical characteristics of this rare pathology and to evaluate the effect of the same or contralateral lobular localization of these two malignancies in clinical and laboratory features. Evaluation of progression-free survival (PFS) in current pathology is one of the important features of our study.All patients diagnosed with simultaneous MTC and PTC after thyroidectomy were evaluated retrospectively. Data on the following variables were recorded: age, gender, tumor localization (ipsilateral lobe located MTC and PTC-Group I, contralateral lobe located MTC and PTC-Group II), tumor size, cervical lymph node metastasis, distant metastasis, tumor stage, postoperative basal calcitonin, carcinoembryonic antigen, thyroglobulin (Tg), and anti-Tg values. In all our cases, since MTC progressed before PTC, progression was accepted as serum calcitonin values exceeded 150 pg/mL.Groups were formed as follows: Group I, four cases where MTC and PTC were localized in different foci in the same lobe; Group II, nine cases where they were localized in different lobes. There was only one case in which two tumors were located in the same focus. The case with dual differentiation was included in Group I (35. 7%). When the PFS of the two groups were compared, no statistically significant difference was found (P = 0.87).As a result of this analysis, the location of the simultaneously detected PTC in the same or different lobes with the MTC does not make a significant difference in clinical and laboratory features.Papillary thyroid cancer (PTC) is the most common histological subtype of thyroid cancer, accounting for 75-80% of all thyroid cancer cases.[1] It originates from follicular cells from the foregut endoderm and produces thyroglobulin (Tg), and thyroid hormones. Medullary thyroid cancer (MTC) accounts for 5-8% of all thyroid cancer cases. [2] It originates from the fourth brachial arch neuroectoderm parafollicular cells, secretes hormonal peptide and calcitonin, and is considered a member of the amine precursor uptake and decarboxylation system. It can also be seen as hereditary or nonhereditary. Hereditary cases appear in the clinic as familial MTC (fMTC) or multiple endocrine neoplasia type 2. The prognoses for these thyroid cancer types are worse than they are for cases of PTC.PTC and MTC are distinct types of thyroid carcinomas with significantly different histology, incidence, cellular origin, and histopathological features. Synchronous occurrence of these two carcinomas is uncommon. The first cases of these carcinomas were described by Lamberg in 1981.[3] The concurrence of medullary and papillary carcinomas represents less than 1% of all thyroid malignancies.[4]Concurrent medullary and follicular cell-derived carcinomas can be divided into three categories: i) synchronous tumors located in different anatomical positions; ii) collision tumors located on each other's borders; iii) true mixed tumors in the same focus. Nonetheless, it remains unclear whether these tumors develop from the same embryogenic origin or are detected incidentally.In 1988, the World Health Organization (WHO) defined the presence of medullary and follicular morphological appearance, immunoreactive calcitonin, and Tg in the same primary tumor as "mixed medullary and follicular thyroid carcinoma". This rare malignancy accounts for less than 1% of all thyroid cancers.[4] Furthermore, this definition does not classify follicular cells as follicular, papillary, poorly differentiated, or anaplastic. According to the WHO, the medullary component determines the prognosis in mixed cases.[5]Purpose:Concurrence of medullary and papillary thyroid carcinoma (MTC and PTC) represents less than 1% of all thyroid malignancies. We aimed to reveal the demographic and clinical characteristics of this rare pathology and to evaluate the effect of the same or contralateral lobular localization of these two malignancies in clinical and laboratory features. Evaluation of progression-free survival (PFS) in current pathology is one of the important features of our study.All patients diagnosed with simultaneous MTC and PTC after thyroidectomy were evaluated retrospectively. Data on the following variables were recorded: age, gender, tumor localization (ipsilateral lobe located MTC and PTC-Group I, contralateral lobe located MTC and PTC-Group II), tumor size, cervical lymph node metastasis, distant metastasis, tumor stage, postoperative basal calcitonin, carcinoembryonic antigen, thyroglobulin (Tg), and anti-Tg values. In all our cases, since MTC progressed before PTC, progression was accepted as serum calcitonin values exceeded 150 pg/mL.Groups were formed as follows: Group I, four cases where MTC and PTC were localized in different foci in the same lobe; Group II, nine cases where they were localized in different lobes. There was only one case in which two tumors were located in the same focus. The case with dual differentiation was included in Group I (35. 7%). When the PFS of the two groups were compared, no statistically significant difference was found (P = 0.87).As a result of this analysis, the location of the simultaneously detected PTC in the same or different lobes with the MTC does not make a significant difference in clinical and laboratory features.Papillary thyroid cancer (PTC) is the most common histological subtype of thyroid cancer, accounting for 75-80% of all thyroid cancer cases. [1] It originates from follicular cells from the foregut endoderm and produces thyroglobulin (Tg), and thyroid hormones. Medullary thyroid cancer (MTC) accounts for 5-8% of all thyroid cancer cases.[2] It originates from the fourth brachial arch neuroectoderm parafollicular cells, secretes hormonal peptide and calcitonin, and is considered a member of the amine precursor uptake and decarboxylation system. It can also be seen as hereditary or nonhereditary. Hereditary cases appear in the clinic as familial MTC (fMTC) or multiple endocrine neoplasia type 2. The prognoses for these thyroid cancer types are worse than they are for cases of PTC.PTC and MTC are distinct types of thyroid carcinomas with significantly different histology, incidence, cellular origin, and histopathological features. Synchronous occurrence of these two carcinomas is uncommon. The first cases of these carcinomas were described by Lamberg in 1981.[3] The concurrence of medullary and papillary carcinomas represents less than 1% of all thyroid malignancies.[4]Concurrent medullary and follicular cell-derived carcinomas can be divided into three categories: i) synchronous tumors located in different anatomical positions; ii) collision tumors located on each other's borders; iii) true mixed tumors in the same focus. Nonetheless, it remains unclear whether these tumors develop from the same embryogenic origin or are detected incidentally.In 1988, the World Health Organization (WHO) defined the presence of medullary and follicular morphological appearance, immunoreactive calcitonin, and Tg in the same primary tumor as "mixed medullary and follicular thyroid carcinoma". This rare malignancy accounts for less than 1% of all thyroid cancers.[4] Furthermore, this definition does not classify follicular cells as follicular, papillary, poorly differentiated, or anaplastic. According to the WHO, the medullary component determines the prognosis in mixed cases.[5]