Case Report
Extramedullary plasmacytoma of thyroid — a mimicker of medullary carcinoma at fine needle aspiration cytology: A case report ABSTRACT A rare case of extra medullary plasmacytoma (EMP) of thyroid gland in a 60 year old male, occurring against a background of Hashimoto’s thyroiditis is reported. The fine needle aspiration cytology (FNAC) initially done as an outpatient procedure, showed atypical epithelial cells on a background of amyloid. Considering these findings we gave a diagnosis of medullary carcinoma. Histology of the total thyroidectomy specimen showed an extensive infiltration of neoplastic plasma cells against a background of Hashimoto’s thyroiditis, with a bizarre Hurthle cell change. Immunohistochemistry on the histology sections confirmed the diagnosis of solitary plasmacytoma of thyroid against a background of Hashimoto’s thyroiditis. Key words: Extramedullary plasmacytoma; fine needle aspiration cytology (FNAC); medullary carcinoma; thyroid
Introduction
Case Report
Solitary plasmacytoma of the thyroid is an uncommon neoplasm constituting 1.4% of the extramedullar y plasmacytomas (EMPs). The patients are often middle-aged to older adults, with a slight male predominance.[1,2] There are many reported cases of solitary plasmacytomas of the extrathyroidal sites diagnosed on fine needle aspiration cytology (FNAC) in literature.[3,4] A diagnosis of solitary plasmacytoma of the thyroid made during FNAC, however, to the best of our knowledge, is rare and unique.[4] The present case illustrates the difficulty in arriving at an FNAC diagnosis of solitary plasmacytoma of the thyroid, due to the presence of atypical Hurthle cells and the associated amyloid in the tumor.
A 60-year-old male presented with a neck mass, hoarseness of voice, and dysphagia of a three-month duration. On clinical examination the thyroid gland was diffusely enlarged, more prominent on the right side, firm, and painless. The thyroid profile showed hypothyroidism. An ultrasound examination showed hypoechoic areas in both lobes suggestive of a spaceoccupying lesion.
Access this article online Quick Response Code Website: www.jcytol.org
The FNAC revealed a cellular aspirate composed of cells arranged in numerous acini, loose clusters, pseudopapillae, as well as singly dispersed [Figure 1a]. The cells were round to ovoid, with enlarged nuclei and fine chromatin. Many cells showed nuclear grooves as well as marked anisonucleosis, with occasional intranuclear cytoplasmic inclusions [Figure 1c]. The cytoplasm was abundant, pink, and granular in most of the cells [Figure 1b]. The background showed a few lymphocytes and spindle-shaped cells. Occasional multinucleate giant cells were observed. A pink amorphous acellular material was identified as large blobs and stained positive for Congo red [Figure 1d]. It showed an apple green birefringence on polarising microscopy.
DOI:
A possibility of an epithelial neoplasm, either medullary carcinoma (pleomorphic variant) or a follicular variant
10.4103/0970-9371.130710
VIDYA BHAT, SHAMEEM SHARIFF, ROOPA A NARAYANA REDDY Department of Pathology, MVJ Medical College and Research Hospital, Bangalore, Karnataka, India Address of correspondence: Dr. Vidya Bhat, Department of Pathology, MVJ Medical College and Research Hospital, Dandupalaya, Kolathur(P), Hoskote, Bangalore - 562 114, Karnataka, India. E-mail: [email protected]
Journal of Cytology / January 2014 / Volume 31 / Issue 1
53
Bhat, et al.: FNAC of extramedullary plasmacytoma of thyroid
Figure 1a: Cellular aspirate with acinar cells, papillaroid clusters, and nuclei with grooves (H and E, ×200)
Figure 1b: Acini composed of pleomorphic cells with hyperchroma c nuclei and abundant pink cytoplasm (H and E, ×400)
Figure 1c: Cluster of cells with an intranuclear inclusion (H and E, ×400)
Figure 1d: Posi ve staining amorphous material in smear background (Congo red stain, x200)
of papillary carcinoma was given. This was due to the presence of pleomorphic epithelial cells arranged in groups, acini, and papillaroid structures. However, due to the associated amyloid, a strong possibility of medullary carcinoma over papillary carcinoma was considered. Based on this diagnosis, the patient underwent total thyroidectomy. Gross examination of the thyroidectomy specimen showed the right lobe to be with an isthmus measuring 7 × 5 × 4 cm and the left lobe measuring 5 × 4 × 3 cm. The cut surfaces of both were nodular and fleshy in appearance [Figure 2a]. Histopathology: The multiple sections studied, revealed diffuse atypical plasma cells in sheets effacing the normal thyroid parenchyma [Figure 2b]. The intervening areas and thyroid tissue at the periphery showed Hashimoto thyroiditis, with extensive oncocytic change and bizarre nuclear changes. Numerous lymphoepithelial lesions were also noted, with follicular colonization of acini by lymphocytes. Amorphous material, consistent with an amyloid, was identified amidst 54
the neoplastic cells. A diagnosis of plasmacytoma of the thyroid gland was made on histology. A close differential considered on histology was marginal zone lymphoma with extensive plasma cell differentiation. Immunohistochemistry revealed plasmacytoid cells with diffuse positivity for CD138 [Figure 2c], and also cytoplasmic positivity for the Kappa light chain. The tumor cells were negative for CD19 [Figure 2d] and CD20. On the basis of immunohistochemistry a final diagnosis of extramedullary solitary plasmacytoma (ESP) of the thyroid was made, after the workup was found to be negative for multiple myeloma.
Discussion Extramedullary plasmacytoma is a rare lesion.[1] A diagnosis of this neoplasm by FNAC has been made at extrathyroidal sites even without the help of immunohistochemistry.[3,4] The present case is an example of solitary plasmacytoma of the thyroid, which was diagnosed, after FNAC, as a medullary
Journal of Cytology / January 2014 / Volume 31 / Issue 1
Bhat, et al.: FNAC of extramedullary plasmacytoma of thyroid
Figure 2a: Cut surface of the total thyroidectomy specimen showing a lobulated fleshy appearance
Figure 2b: Thyroid follicles lined by Hurthle cells with intervening sheets of neoplas c plasma cells (H and E, ×400)
Figure 2c: Neoplas c cells showing diffuse cytoplasmic posi vity for CD138 indica ng plasma cell differen a on (IHC, x400)
Figure 2d: Germinal center cells (reac ve and part of Hashimoto thyroidi s) showing CD19 posi vity (IHC, ×200)
carcinoma, for various reasons outlined below. The needle had sampled predominantly follicular epithelial cells from the periphery of the lesion, which represented changes of Hashimoto thyroiditis (the background in the aspirate showed mononuclear cells, which are predominantly lymphocytes). The predominant component of the aspirate constituted Hurthle cell clusters with bizarre nuclear morphology (mistaken for carcinoma). Some granularity of the cytoplasm and abundant acellular material, which was positive for an amyloid stain, suggested a diagnosis of medullary carcinoma on the aspirate. The neoplastic plasma cells did not constitute the component of the aspirate.
mimics of malignant cells. They are known to show atypical nuclear changes and hyperchromasia and this has been welldocumented in literature.[7,8] Nuclear grooves are also a feature of Hurthle cells.[8] Most probably, multiple aspirations could have avoided this misinterpretation, but even so, the presence of amyloid in the aspirate associated with some epithelial cells tilted the diagnosis toward a medullary carcinoma.
Fine Needle Aspiration Cytology, as outlined in this case, emphasises the limitation of being a diagnostic tool in all thyroid malignancies. A similar case of solitary plasmacytoma of the thyroid has been documented in literature by Bourtsos et al.,[5,6] who have also demonstrated this pitfall in aspiration cytology diagnosis. Hurthle cells are notorious
Bourtsos et al.[5] have emphasized that EMP should be considered in the differential diagnosis of a neck mass that yields discohesive cells associated with amyloid-like material. They made a diagnosis of medullary carcinoma due to the presence of plasmacytoid tumor cells with an amyloid in the background. The present authors mistook Hurthle cells for cells of a pelomorphic variant of medullary carcinoma. The confusion toward malignancy was compounded due the presence of intranuclear inclusions in these cells as well as grooves. Similarly Ridal et al.[9] diagnosed a case of EMP as lymphoplasmacytic lymphoma on cytology. Sarin
Journal of Cytology / January 2014 / Volume 31 / Issue 1
55
Bhat, et al.: FNAC of extramedullary plasmacytoma of thyroid
et al.[10] reported five cases of EMPs on cytology and observed plasmacytoid cells with varying pleomorphisms, bi- and multinucleation, and mitotic figures. All these features posed a diagnostic challenge for them on cytological evaluation.
2.
At histology, although plasmacytoma was considered as a diagnosis, the other close differential was marginal zone lymphoma, with extensive plasma cell differentiation, which was the more common occurrence in the thyroid, as compared to plasmacytomas.[6,11] On immunohistochemistry, the plasmacytomas were negative for CD45, CD19, and CD 20, and strongly positive for CD138.[12] Marginal zone lymphomas were, on the contrary, positive for CD45, CD19, and CD20, and would show positivity for CD138, depending on the plasma cell differentiation. The present case was strongly positive for CD138, with light chain restriction for kappa chains, which favored a diagnosis of plasmacytoma.
4.
In conclusion, EMP of the thyroid can be diagnosed on cytology with multiple aspirations, to avoid sampling error and to arrive at the right diagnosis. Amyloid-like material can be associated with this type of tumor and not necessarily be a component of medullary carcinoma alone. The other differentials like lymphoproliferative lesions and plasmacytomas must be kept in mind in the setting of autoimmune thyroiditis, which can be diagnosed on cytology.
References 1.
56
Fletcher CD. Thyroid tumours. In: Diagnostic Histopathology of Tumors. 3rd ed. China: Churchill Livingstone Elsevier; 2007. p. 1051.
3.
5.
6.
7. 8.
9.
10. 11.
12.
Alexiou C, Kau RJ, Dietzfelbinger H, Kremer M, Spiess JC, Schratzenstaller B, et al. Extramedullary plasmacytoma: Tumor occurrence and therapeutic concepts. Cancer 1999;85:2305-14. Saad R, Raab S, Liu Y, Pollice P, Silverman JF. Plasmacytoma of the larynx diagnosed by fine- needle aspiration cytology: A case report. Diagn Cytopathol 2001;24:408-11. Meccawy AA. Plasmacytoma of the thyroid gland: Case report and review of the literature. JKAU Med Sci 2010;17:83-92. Bourtsos EP, Bedrossian CW, De Frias DV, Nayar R. Thyroid plasmacytoma mimicking medullary carcinoma: A potential pitfall in aspiration cytology. Diag Cytopathol 2000;23:354-8. Kovacs CS, Mant MJ, Nguyen GK, Ginsberg J. Plasma cell lesions of the thyroid: Report of a case of solitary plasmacytoma and a review of the literature. Thyroid 1994;4:65-71. Jayaram G. Problems in the interpretation of hürthle cell populations in fine needle aspirates from the thyroid. Acta Cytol 1983;27:84-5. Siddaraju N, Wilfred CD, Singh N, Murugan P, Verma SK. Fine needle aspiration cytology of the thyroid following carbimazole therapy in Graves’ disease: A case report. Internet J Endocrinol 2008;4:2. Ridal M, Ouattassi N, Harmouch T, Amarti A, Alami MN. Solitary extramedullary plasmacytoma of the thyroid gland. Case Rep Otolaryngol 2012; 2012:282784. doi: 10.1155/2012/282784. Epub 2012 Oct 9. Sarin H, Manucha V, Verma K. Extramedullary plasmacytoma, a report of five cases diagnosed by FNAC. J Cytopathol 2009;20:328-31. Aihara H, Tsutsumi Y, Ishikawa H. Extramedullary plasmacytoma of the thyroid, associated with follicular colonization and stromal deposition of polytypic immunoglobulins and major histocompatibility antigens possible categorization in MALT lymphoma. Acta Pathol Jpn 1992;42:672-83. Seegmiller AC, Xu Y, McKenna RW, Karandikar NJ. Immunophenotypic differentiation between neoplastic plasma cells in mature B-cell lymphoma vs plasma cell myeloma. Am J Clin Pathol 2007;127:176-81.
How to cite this article: Bhat V, Shariff S, Narayana Reddy RA. Extramedullary plasmacytoma of thyroid - a mimicker of medullary carcinoma at fine needle aspiration cytology: A case report. J Cytol 2014;31:53-6. Source of Support: Nil. Conflict of Interest: None declared.
Journal of Cytology / January 2014 / Volume 31 / Issue 1
Copyright of Journal of Cytology is the property of Medknow Publications & Media Pvt. Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use.
Extramedullary plasmacytoma of thyroid — a mimicker of medullary carcinoma at fine needle aspiration cytology: A case report ABSTRACT A rare case of extra medullary plasmacytoma (EMP) of thyroid gland in a 60 year old male, occurring against a background of Hashimoto’s thyroiditis is reported. The fine needle aspiration cytology (FNAC) initially done as an outpatient procedure, showed atypical epithelial cells on a background of amyloid. Considering these findings we gave a diagnosis of medullary carcinoma. Histology of the total thyroidectomy specimen showed an extensive infiltration of neoplastic plasma cells against a background of Hashimoto’s thyroiditis, with a bizarre Hurthle cell change. Immunohistochemistry on the histology sections confirmed the diagnosis of solitary plasmacytoma of thyroid against a background of Hashimoto’s thyroiditis. Key words: Extramedullary plasmacytoma; fine needle aspiration cytology (FNAC); medullary carcinoma; thyroid
Introduction
Case Report
Solitary plasmacytoma of the thyroid is an uncommon neoplasm constituting 1.4% of the extramedullar y plasmacytomas (EMPs). The patients are often middle-aged to older adults, with a slight male predominance.[1,2] There are many reported cases of solitary plasmacytomas of the extrathyroidal sites diagnosed on fine needle aspiration cytology (FNAC) in literature.[3,4] A diagnosis of solitary plasmacytoma of the thyroid made during FNAC, however, to the best of our knowledge, is rare and unique.[4] The present case illustrates the difficulty in arriving at an FNAC diagnosis of solitary plasmacytoma of the thyroid, due to the presence of atypical Hurthle cells and the associated amyloid in the tumor.
A 60-year-old male presented with a neck mass, hoarseness of voice, and dysphagia of a three-month duration. On clinical examination the thyroid gland was diffusely enlarged, more prominent on the right side, firm, and painless. The thyroid profile showed hypothyroidism. An ultrasound examination showed hypoechoic areas in both lobes suggestive of a spaceoccupying lesion.
Access this article online Quick Response Code Website: www.jcytol.org
The FNAC revealed a cellular aspirate composed of cells arranged in numerous acini, loose clusters, pseudopapillae, as well as singly dispersed [Figure 1a]. The cells were round to ovoid, with enlarged nuclei and fine chromatin. Many cells showed nuclear grooves as well as marked anisonucleosis, with occasional intranuclear cytoplasmic inclusions [Figure 1c]. The cytoplasm was abundant, pink, and granular in most of the cells [Figure 1b]. The background showed a few lymphocytes and spindle-shaped cells. Occasional multinucleate giant cells were observed. A pink amorphous acellular material was identified as large blobs and stained positive for Congo red [Figure 1d]. It showed an apple green birefringence on polarising microscopy.
DOI:
A possibility of an epithelial neoplasm, either medullary carcinoma (pleomorphic variant) or a follicular variant
10.4103/0970-9371.130710
VIDYA BHAT, SHAMEEM SHARIFF, ROOPA A NARAYANA REDDY Department of Pathology, MVJ Medical College and Research Hospital, Bangalore, Karnataka, India Address of correspondence: Dr. Vidya Bhat, Department of Pathology, MVJ Medical College and Research Hospital, Dandupalaya, Kolathur(P), Hoskote, Bangalore - 562 114, Karnataka, India. E-mail: [email protected]
Journal of Cytology / January 2014 / Volume 31 / Issue 1
53
Bhat, et al.: FNAC of extramedullary plasmacytoma of thyroid
Figure 1a: Cellular aspirate with acinar cells, papillaroid clusters, and nuclei with grooves (H and E, ×200)
Figure 1b: Acini composed of pleomorphic cells with hyperchroma c nuclei and abundant pink cytoplasm (H and E, ×400)
Figure 1c: Cluster of cells with an intranuclear inclusion (H and E, ×400)
Figure 1d: Posi ve staining amorphous material in smear background (Congo red stain, x200)
of papillary carcinoma was given. This was due to the presence of pleomorphic epithelial cells arranged in groups, acini, and papillaroid structures. However, due to the associated amyloid, a strong possibility of medullary carcinoma over papillary carcinoma was considered. Based on this diagnosis, the patient underwent total thyroidectomy. Gross examination of the thyroidectomy specimen showed the right lobe to be with an isthmus measuring 7 × 5 × 4 cm and the left lobe measuring 5 × 4 × 3 cm. The cut surfaces of both were nodular and fleshy in appearance [Figure 2a]. Histopathology: The multiple sections studied, revealed diffuse atypical plasma cells in sheets effacing the normal thyroid parenchyma [Figure 2b]. The intervening areas and thyroid tissue at the periphery showed Hashimoto thyroiditis, with extensive oncocytic change and bizarre nuclear changes. Numerous lymphoepithelial lesions were also noted, with follicular colonization of acini by lymphocytes. Amorphous material, consistent with an amyloid, was identified amidst 54
the neoplastic cells. A diagnosis of plasmacytoma of the thyroid gland was made on histology. A close differential considered on histology was marginal zone lymphoma with extensive plasma cell differentiation. Immunohistochemistry revealed plasmacytoid cells with diffuse positivity for CD138 [Figure 2c], and also cytoplasmic positivity for the Kappa light chain. The tumor cells were negative for CD19 [Figure 2d] and CD20. On the basis of immunohistochemistry a final diagnosis of extramedullary solitary plasmacytoma (ESP) of the thyroid was made, after the workup was found to be negative for multiple myeloma.
Discussion Extramedullary plasmacytoma is a rare lesion.[1] A diagnosis of this neoplasm by FNAC has been made at extrathyroidal sites even without the help of immunohistochemistry.[3,4] The present case is an example of solitary plasmacytoma of the thyroid, which was diagnosed, after FNAC, as a medullary
Journal of Cytology / January 2014 / Volume 31 / Issue 1
Bhat, et al.: FNAC of extramedullary plasmacytoma of thyroid
Figure 2a: Cut surface of the total thyroidectomy specimen showing a lobulated fleshy appearance
Figure 2b: Thyroid follicles lined by Hurthle cells with intervening sheets of neoplas c plasma cells (H and E, ×400)
Figure 2c: Neoplas c cells showing diffuse cytoplasmic posi vity for CD138 indica ng plasma cell differen a on (IHC, x400)
Figure 2d: Germinal center cells (reac ve and part of Hashimoto thyroidi s) showing CD19 posi vity (IHC, ×200)
carcinoma, for various reasons outlined below. The needle had sampled predominantly follicular epithelial cells from the periphery of the lesion, which represented changes of Hashimoto thyroiditis (the background in the aspirate showed mononuclear cells, which are predominantly lymphocytes). The predominant component of the aspirate constituted Hurthle cell clusters with bizarre nuclear morphology (mistaken for carcinoma). Some granularity of the cytoplasm and abundant acellular material, which was positive for an amyloid stain, suggested a diagnosis of medullary carcinoma on the aspirate. The neoplastic plasma cells did not constitute the component of the aspirate.
mimics of malignant cells. They are known to show atypical nuclear changes and hyperchromasia and this has been welldocumented in literature.[7,8] Nuclear grooves are also a feature of Hurthle cells.[8] Most probably, multiple aspirations could have avoided this misinterpretation, but even so, the presence of amyloid in the aspirate associated with some epithelial cells tilted the diagnosis toward a medullary carcinoma.
Fine Needle Aspiration Cytology, as outlined in this case, emphasises the limitation of being a diagnostic tool in all thyroid malignancies. A similar case of solitary plasmacytoma of the thyroid has been documented in literature by Bourtsos et al.,[5,6] who have also demonstrated this pitfall in aspiration cytology diagnosis. Hurthle cells are notorious
Bourtsos et al.[5] have emphasized that EMP should be considered in the differential diagnosis of a neck mass that yields discohesive cells associated with amyloid-like material. They made a diagnosis of medullary carcinoma due to the presence of plasmacytoid tumor cells with an amyloid in the background. The present authors mistook Hurthle cells for cells of a pelomorphic variant of medullary carcinoma. The confusion toward malignancy was compounded due the presence of intranuclear inclusions in these cells as well as grooves. Similarly Ridal et al.[9] diagnosed a case of EMP as lymphoplasmacytic lymphoma on cytology. Sarin
Journal of Cytology / January 2014 / Volume 31 / Issue 1
55
Bhat, et al.: FNAC of extramedullary plasmacytoma of thyroid
et al.[10] reported five cases of EMPs on cytology and observed plasmacytoid cells with varying pleomorphisms, bi- and multinucleation, and mitotic figures. All these features posed a diagnostic challenge for them on cytological evaluation.
2.
At histology, although plasmacytoma was considered as a diagnosis, the other close differential was marginal zone lymphoma, with extensive plasma cell differentiation, which was the more common occurrence in the thyroid, as compared to plasmacytomas.[6,11] On immunohistochemistry, the plasmacytomas were negative for CD45, CD19, and CD 20, and strongly positive for CD138.[12] Marginal zone lymphomas were, on the contrary, positive for CD45, CD19, and CD20, and would show positivity for CD138, depending on the plasma cell differentiation. The present case was strongly positive for CD138, with light chain restriction for kappa chains, which favored a diagnosis of plasmacytoma.
4.
In conclusion, EMP of the thyroid can be diagnosed on cytology with multiple aspirations, to avoid sampling error and to arrive at the right diagnosis. Amyloid-like material can be associated with this type of tumor and not necessarily be a component of medullary carcinoma alone. The other differentials like lymphoproliferative lesions and plasmacytomas must be kept in mind in the setting of autoimmune thyroiditis, which can be diagnosed on cytology.
References 1.
56
Fletcher CD. Thyroid tumours. In: Diagnostic Histopathology of Tumors. 3rd ed. China: Churchill Livingstone Elsevier; 2007. p. 1051.
3.
5.
6.
7. 8.
9.
10. 11.
12.
Alexiou C, Kau RJ, Dietzfelbinger H, Kremer M, Spiess JC, Schratzenstaller B, et al. Extramedullary plasmacytoma: Tumor occurrence and therapeutic concepts. Cancer 1999;85:2305-14. Saad R, Raab S, Liu Y, Pollice P, Silverman JF. Plasmacytoma of the larynx diagnosed by fine- needle aspiration cytology: A case report. Diagn Cytopathol 2001;24:408-11. Meccawy AA. Plasmacytoma of the thyroid gland: Case report and review of the literature. JKAU Med Sci 2010;17:83-92. Bourtsos EP, Bedrossian CW, De Frias DV, Nayar R. Thyroid plasmacytoma mimicking medullary carcinoma: A potential pitfall in aspiration cytology. Diag Cytopathol 2000;23:354-8. Kovacs CS, Mant MJ, Nguyen GK, Ginsberg J. Plasma cell lesions of the thyroid: Report of a case of solitary plasmacytoma and a review of the literature. Thyroid 1994;4:65-71. Jayaram G. Problems in the interpretation of hürthle cell populations in fine needle aspirates from the thyroid. Acta Cytol 1983;27:84-5. Siddaraju N, Wilfred CD, Singh N, Murugan P, Verma SK. Fine needle aspiration cytology of the thyroid following carbimazole therapy in Graves’ disease: A case report. Internet J Endocrinol 2008;4:2. Ridal M, Ouattassi N, Harmouch T, Amarti A, Alami MN. Solitary extramedullary plasmacytoma of the thyroid gland. Case Rep Otolaryngol 2012; 2012:282784. doi: 10.1155/2012/282784. Epub 2012 Oct 9. Sarin H, Manucha V, Verma K. Extramedullary plasmacytoma, a report of five cases diagnosed by FNAC. J Cytopathol 2009;20:328-31. Aihara H, Tsutsumi Y, Ishikawa H. Extramedullary plasmacytoma of the thyroid, associated with follicular colonization and stromal deposition of polytypic immunoglobulins and major histocompatibility antigens possible categorization in MALT lymphoma. Acta Pathol Jpn 1992;42:672-83. Seegmiller AC, Xu Y, McKenna RW, Karandikar NJ. Immunophenotypic differentiation between neoplastic plasma cells in mature B-cell lymphoma vs plasma cell myeloma. Am J Clin Pathol 2007;127:176-81.
How to cite this article: Bhat V, Shariff S, Narayana Reddy RA. Extramedullary plasmacytoma of thyroid - a mimicker of medullary carcinoma at fine needle aspiration cytology: A case report. J Cytol 2014;31:53-6. Source of Support: Nil. Conflict of Interest: None declared.
Journal of Cytology / January 2014 / Volume 31 / Issue 1
Copyright of Journal of Cytology is the property of Medknow Publications & Media Pvt. Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use.
