Colloid Carcinoma-Breast

Background

This variant of infiltrating ductal carcinoma of the breast has an excellent prognosis.

OUTLINE

Epidemiology

Disease Associations

Pathogenesis

Laboratory/Radiologic/Other Diagnostic Testing

Gross Appearance and Clinical Variants

Histopathological Features and Variants

Special Stains/Immunohistochemistry/Electron Microscopy

Differential Diagnosis

Prognosis and Treatment

Commonly Used Terms

EPIDEMIOLOGY CHARACTERIZATION

SYNONYMS Mucinous carcinoma
Colloid carcinoma

INCIDENCE 7% of tumors in women 75 years or older

AGE RANGE-MEDIAN Usually older than nonmucinous tumors

GROSS APPEARANCE/
CLINICAL VARIANTS CHARACTERIZATION

GENERAL

VARIANTS

ADVANCED

Locally advanced mucinous carcinoma of the breast with sudden growth acceleration: a case report.

Ishikawa T, Hamaguchi Y, Ichikawa Y, Shimura M, Kawano N, Nakatani Y, Ohnishi H, Maegawa J, Ogino I, Shimada H.

Department of Surgery, Yokohama City University, School of Medicine, Yokohama, Japan.
Jpn J Clin Oncol 2002 Feb;32(2):64-7 Abstract quote
We report a 35-year-old woman with locally advanced mucinous carcinoma of the breast with sudden growth acceleration. A pea-sized mass developed into an ulcerated large tumor within 1 month. After the combination of chemotherapy, radiation and hyperthermia, a radical mastectomy was performed, followed by repair of the skin defect by latissimus dorsi and rectus abdominis musculocutaneous flaps.

Histological examination revealed a pure mucinous carcinoma with axillary lymph node involvement. Estrogen and progesterone receptors were not detected in the tumor. Twenty-five months after treatment, there is no sign of recurrent disease. Pure mucinous carcinoma generally has a less aggressive growth pattern as defined by tumor size, adherence to the overlying skin/bottom fasciae, estrogen and progesterone receptor positive and primary lymph axillary lymph node metastases.

This case showed completely opposite features to all of these typical biological features of pure mucinous carcinomas.

HISTOLOGICAL TYPES CHARACTERIZATION

GENERAL

Human mucinous breast carcinomas and their lymph node metastases. A histological review of 247 cases.

Rasmussen BB.
Pathol Res Pract 1985 Oct;180(4):377-82 Abstract quote
In a histologic reevaluation of 247 primary human mucinous breast carcinomas, 207 tumors fullfilled the criteria for further histopathological evaluation. The criteria for entrance in this survey are that at least 25% of the tumor consists of areas of extracellular mucin with small islands of solid epithelial tumor tissue floating in the mucin, and that the extracellular mucin should comprise at least 33% of the total tumor volume.

The 247 carcinomas that have been further evaluated have been subclassified into two groups: "pure" mucinous breast carcinomas that consist solely of tumor tissue with extracellular mucin production (95 tumors), and "mixed" mucinous carcinomas that also contain infiltrating carcinoma without extracellular mucin (112 tumor). A significantly greater number of mixed carcinomas than pure carcinomas have an aggressive growth pattern--as defined by tumor size, adherence to overlying skin/bottom fascie, and primary axillary lymph node metastases. The histogenesis of the mucinous carcinomas is briefly discussed in relation to the present observations and the literature.

The importance of clearly distinguishing between the mixed and the pure mucinous carcinomas in the diagnosis of these tumors is emphasized.

Mucinous carcinoma of the breast: a pathologic study of 82 cases.

Andre S, Cunha F, Bernardo M, Meneses e Sousa J, Cortez F, Soares J.

Departamento de Patologia Morfologica, Instituto Portugues de Oncologia de Francisco Gentil, Lisboa.
J Surg Oncol 1995 Mar;58(3):162-7 Abstract quote
A series of 82 consecutive cases of mucinous carcinomas of the female breast was investigated for their clinical, morphological, and histochemical features and for the influence of some tumor characteristics on its prognosis.

Two groups, a "pure" subtype (n = 58) and a "mixed" subtype (n = 24), were considered, according to the absence or the presence of concomitant areas with typical infiltrating ductal carcinoma. Eighty patients were followed with an average of 7.4 years. The actuarial survival was 58.5% at 10 years. The group of pure mucinous carcinomas showed a statistically significant better prognosis (P = 0.0007) than that of the group of mixed tumors, as well as a lower percentage of axillary nodal metastasis. Tumor dimension of both pure and mixed mucinous carcinomas influenced the prognosis, since patients with T1 tumors had longer survival than those with T2 tumors (P = 0.05) and the latter showed less mortality than T3 tumor cases (P = 0.036). Node-negative patients also had a more favorable outcome with lower mortality than node positive patients (P = 0.007).

None of the T1 pure mucinous carcinomas had axillary metastasis, which may have implications for the surgical protocols. The evaluation of quantitative and qualitative content in mucosubstances did not correlate with the prognosis. However, sulfomucins were demonstrated in 30.5% of cases; this fact points to add breast carcinoma to the group of neoplasms that may present as a metastatic sulfomucin-producing adenocarcinoma.

Can Mucinous Lesions of the Breast Be Reliably Diagnosed by Core Needle Biopsy?

Andrew A. Renshaw, MD

Am J Clin Pathol 2002;118:82-84 Abstract quote

Lesions of the breast containing extravasated mucin span a continuum from benign mucoceles to invasive mucinous (colloid) carcinoma. It is well known that distinguishing benign from malignant mucinous lesions is difficult in fine-needle aspiration material. Whether these lesions also are difficult to distinguish in core needle biopsy material is not known.

To address this, I reviewed the results of 4,297 breast core needle biopsies. Mucinous lesions were identified in 22 cases (0.51%), and excisional biopsy material was available for 15 of these. At excision, 0 of 8 benign mucinous lesions showed carcinoma, while 7 of 7 mucinous lesions associated with carcinoma at the time of core needle biopsy showed carcinoma at excision.

The vast majority of mucinous lesions of the breast can be diagnosed accurately by core needle biopsy. Whether all such lesions require excision is not known at this time.

VARIANTS

SPECIAL STAINS/IMMUNOPEROXIDASE/
OTHER CHARACTERIZATION

SPECIAL STAINS

Mucinous (colloid) adenocarcinomas secrete distinct O-acylated forms of sialomucins: a histochemical study of gastric, colorectal and breast adenocarcinomas.

Saez C, Japon MA, Poveda MA, Segura DI.

Laboratory of Histochemistry, Department of Pathology, Hospital Universitario Virgen del Rocio, Avenida Manuel Siurot s/n, Seville 41013, Spain.
Histopathology 2001 Dec;39(6):554-60 Abstract quote
AIMS: Mucinous (colloid) adenocarcinomas represent a distinct group of tumours defined by the presence of large amounts of extracellular mucins. By using histochemical methods, we analysed mucins secreted by mucinous versus non-mucinous adenocarcinomas and looked for differential secretion profiles.

METHODS AND RESULTS: Sixty-four adenocarcinomas were studied (23 colorectal, 17 gastric, and 24 breast tumours). Thirty-two tumours were of the colloid type. The following methods were applied to paraffin tissue sections: (i) Alcian blue (pH 2.5) and periodic acid-Schiff (PAS); (ii) high iron diamine and Alcian blue (pH 2.5); (iii) periodic acid borohydride, potassium hydroxide, and PAS; (iv) periodic acid-thionine Schiff, potassium hydroxide, and PAS; and (v) periodic acid-borohydride and PAS. Most adenocarcinomas secreted acidic mucins, with sialomucins predominating over sulfomucins, except for non-mucinous adenocarcinomas of the breast which showed predominant neutral mucins. All mucinous adenocarcinomas contained C9-O-acyl sialic acid as mono, di(C8,C9)-, or tri(C7,C8,C9)-O-acyl forms. Acidic mucins secreted by the majority of non-colloid adenocarcinomas consisted of non-O-acylated sialomucins.

CONCLUSIONS: C9-O-acylation of sialic acid is a characteristic feature of mucinous adenocarcinomas and can be readily detected by histochemical methods.

IMMUNOPEROXIDASE

DIFFERENTIAL DIAGNOSIS KEY DIFFERENTIATING FEATURES

PAPILLARY TUMORS

Can true papillary neoplasms of breast and their mimickers be accurately classified by cytology?

Michael CW, Buschmann B.

University of Michigan, Department of Pathology, Ann Arbor, Michigan 48105, USA.
Cancer 2002 Apr 25;96(2):92-100 Abstract quote
BACKGROUND: The cytologic accuracy in assessing malignancy in papillary breast neoplasms (PBNs) is controversial. This is further complicated by overlapping features observed in other breast lesions that produce papillary-like tissue fragments.

METHODS: The authors reviewed 22 fine-needle aspirates (FNAs) from histologically proven papillary neoplasms: papillary carcinoma (PCA; 10 aspirates) and intraductal papilloma (IDP; 12 aspirates). They also reviewed 8 FNAs in which a papillary neoplasm was suggested by cytology but not confirmed by follow-up biopsy: fibroadenoma (6), mucinous carcinoma (1), and cribriform ductal carcinoma in situ (1).

RESULTS: Papillary carcinoma can be distinguished from IDP by the higher cellularity, more complex papillae with thin disorganized fronds, mild to moderate nuclear atypia, and prominent dissociation with many single papillae. Fibrovascular cores (FVCs) were more common in PCA than IDP in which detached fibrous tissue fragments were frequently seen. Atypical IDP exhibited features intermediate between PCA and IDP. Apocrine metaplasia was variably present in IDP, atypical IDP, and fibroadenoma but absent in all carcinomas. Intraductal papilloma can be distinguished from fibroadenoma by their broad ruffled branches, scalloped borders, and tiny tongue-like projections. True papillae were commonly covered by tall columnar cells. Myoepithelial cells were few in IDP but were numerous in fibroadenoma. The epithelial fragments in nonpapillary lesions presented as cellular spheres and/or complex sheets with finger-like projections but lacked FVCs and columnar cells.

CONCLUSIONS: Papillary breast neoplasms can be accurately classified by cytology. Closer evaluation of the tissue fragments architecture and the background can help in separating PBN from their mimics.

PROGNOSIS AND TREATMENT CHARACTERIZATION

PROGNOSTIC FACTORS

GENERAL

Pure mucinous carcinoma of the breast: a clinicopathologic correlation study.

Avisar E, Khan MA, Axelrod D, Oza K.

Department of Surgery, Beth Israel Medical Center, New York, New York, USA.
Ann Surg Oncol 1998 Jul-Aug;5(5):447-51 Abstract quote
BACKGROUND: Pure mucinous carcinoma (PMC) of the breast has a better prognosis than does invasive ductal carcinoma not otherwise specified and is more prevalent in older patients. We investigated the correlation between prognostic indices and clinical outcome in this histologic subset.

METHODS: A retrospective review was done of patients with PMC treated between 1989 and 1996. Demographic data, pathologic indices of prognosis, axillary nodal status, and outcome were assessed.

RESULTS: Out of 6083 cases of breast carcinoma, 30 were PMC. Only 3 of 25 (12%) axillary dissections were positive. The average age of the group with positive nodes was 57 years, as compared to 69.5 years (95% CI; 63.24-75.76) in the group with negative nodes. All the tumors with positive nodes were aneuploid and had a high nuclear grade, compared to a 31.25% aneuploidy rate in the group without nodal disease (P = .058). Negative ER receptors were found in only 2 of 20 (10%) of the patients tested. Both had axillary disease (P = .016). Tumor size did not correlate with axillary metastasis. Two of the 29 patients died from unrelated diseases. The other 27 patients are alive with no evidence of disease.

CONCLUSIONS: Axillary nodal disease is rare in PMC and correlates with a younger age, aneuploidy, high nuclear grade, or a negative ER receptor status. Sentinel lymph node biopsy may help identify the need for axillary dissection.

RECURRENCE

Mucinous carcinoma of the breast: recurrence 30 years after mastectomy.

Scharnhorst D, Huntrakoon M.

Department of Pathology and Oncology, University of Kansas Medical Center, Kansas City 66103.
South Med J 1988 May;81(5):656-7 Abstract quote
We have reported a case of mucinous breast carcinoma that recurred in the form of lung and lymph node metastases 30 years after definitive resection.

This case emphasizes the indolent nature of this neoplasm and the need to lengthen the period of follow-up for patients with this form of cancer.

STAGING

Pure mucinous carcinoma of the breast: is axillary staging necessary?

Paramo JC, Wilson C, Velarde D, Giraldo J, Poppiti RJ, Mesko TW.

Department of Surgery, Mount Sinai Medical Center, Miami Beach, Florida 33140, USA.
Ann Surg Oncol 2002 Mar;9(2):161-4 Abstract quote
BACKGROUND: Mucinous carcinoma of the breast (MCB) may be associated with a low risk of axillary metastases.

METHODS: To evaluate the incidence of axillary nodal metastasis in MCB, a review of all cases from January 1990 to July 2000 was performed. Pure MCB was defined as all tumor cells being completely surrounded by mucin. Patient demographics, tumor size, estrogen receptor status, total number of dissected lymph nodes, and incidence of nodal metastasis were studied. Deeper sections on the lymph nodes from the pure tumors were performed and stained with low-molecular cytokeratin.

RESULTS: Nineteen cases of pure MCB and 41 cases of mixed MCB were identified. Patients with pure MCB were older than those with mixed MCB. Tumor size and estrogen receptor status showed no statistically significant differences between the two groups. None of the patients with pure MCB demonstrated lymph node metastases, whereas 12 of 41 cases with mixed MCB demonstrated metastatic lymph node involvement.

CONCLUSIONS: Because pure MCB seems unlikely to metastasize, axillary lymph node staging in these patients may not be necessary. The presence of lymph node metastases strongly indicates the presence of a mixed MCB.

TREATMENT

Pathological features of mucinous carcinoma of the breast are favourable for breast-conserving therapy.

Anan K, Mitsuyama S, Tamae K, Nishihara K, Iwashita T, Abe Y, Ihara T, Nakahara S, Katsumoto F, Toyoshima S.

Department of Surgery, Kitakyushu Municipal Medical Centre, Kitakyushu, Fukuoka 802-0077, Japan.

Eur J Surg Oncol 2001 Aug;27(5):459-63 Abstract quote

AIM: The effectiveness of breast-conserving therapy for mucinous carcinoma has not been well documented. We examined clinical and pathological features of cases to determine whether patients with mucinous carcinoma were suitable candidates for this treatment.

METHOD: Cases of pure type (n=52) and mixed type (n=24) mucinous carcinomas were reviewed with emphasis on the risk factors associated with local recurrences after breast-conserving therapy.

RESULTS: Large pure mucinous carcinomas had a low incidence of extensive intraductal spreading (EIS). An inverse correlation existed between the incidence of EIS and tumour size (P<0.05). Comedo type EIS was infrequent (11%) in pure mucinous carcinoma. Incidences of lymphatic vessel invasion (4%) and nodal involvement (4%) were lower in pure mucinous carcinoma than in mixed carcinoma (P<0.05). No nodal involvement occurred in patients with pure mucinous carcinoma less than 3 cm in diameter.

CONCLUSIONS: Patients with pure mucinous carcinomas, except those invading the local skin, are suitable candidates for breast-conserving therapy. Most pure mucinous carcinomas, including a large tumour up to 5 cm in diameter, can be treated with this therapy.

Rosai J. Ackerman's Surgical Pathology. Eight Edition. Mosby 1996.
Sternberg S. Diagnostic Surgical Pathology. Third Edition. Lipincott Williams and Wilkins 1999.
Robbins Pathologic Basis of Disease. Sixth Edition. WB Saunders 1999.
DeMay RM. The Art and Science of Cytopathology. Volume 1 and 2. ASCP Press. 1996.

Commonly Used Terms

Breast Cancer

Last Updated 7/8/2002

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HISTOLOGICAL TYPES	CHARACTERIZATION
GENERAL
Human mucinous breast carcinomas and their lymph node metastases. A histological review of 247 cases. Rasmussen BB.	Pathol Res Pract 1985 Oct;180(4):377-82 Abstract quote In a histologic reevaluation of 247 primary human mucinous breast carcinomas, 207 tumors fullfilled the criteria for further histopathological evaluation. The criteria for entrance in this survey are that at least 25% of the tumor consists of areas of extracellular mucin with small islands of solid epithelial tumor tissue floating in the mucin, and that the extracellular mucin should comprise at least 33% of the total tumor volume. The 247 carcinomas that have been further evaluated have been subclassified into two groups: "pure" mucinous breast carcinomas that consist solely of tumor tissue with extracellular mucin production (95 tumors), and "mixed" mucinous carcinomas that also contain infiltrating carcinoma without extracellular mucin (112 tumor). A significantly greater number of mixed carcinomas than pure carcinomas have an aggressive growth pattern--as defined by tumor size, adherence to overlying skin/bottom fascie, and primary axillary lymph node metastases. The histogenesis of the mucinous carcinomas is briefly discussed in relation to the present observations and the literature. The importance of clearly distinguishing between the mixed and the pure mucinous carcinomas in the diagnosis of these tumors is emphasized.
Mucinous carcinoma of the breast: a pathologic study of 82 cases. Andre S, Cunha F, Bernardo M, Meneses e Sousa J, Cortez F, Soares J. Departamento de Patologia Morfologica, Instituto Portugues de Oncologia de Francisco Gentil, Lisboa.	J Surg Oncol 1995 Mar;58(3):162-7 Abstract quote A series of 82 consecutive cases of mucinous carcinomas of the female breast was investigated for their clinical, morphological, and histochemical features and for the influence of some tumor characteristics on its prognosis. Two groups, a "pure" subtype (n = 58) and a "mixed" subtype (n = 24), were considered, according to the absence or the presence of concomitant areas with typical infiltrating ductal carcinoma. Eighty patients were followed with an average of 7.4 years. The actuarial survival was 58.5% at 10 years. The group of pure mucinous carcinomas showed a statistically significant better prognosis (P = 0.0007) than that of the group of mixed tumors, as well as a lower percentage of axillary nodal metastasis. Tumor dimension of both pure and mixed mucinous carcinomas influenced the prognosis, since patients with T1 tumors had longer survival than those with T2 tumors (P = 0.05) and the latter showed less mortality than T3 tumor cases (P = 0.036). Node-negative patients also had a more favorable outcome with lower mortality than node positive patients (P = 0.007). None of the T1 pure mucinous carcinomas had axillary metastasis, which may have implications for the surgical protocols. The evaluation of quantitative and qualitative content in mucosubstances did not correlate with the prognosis. However, sulfomucins were demonstrated in 30.5% of cases; this fact points to add breast carcinoma to the group of neoplasms that may present as a metastatic sulfomucin-producing adenocarcinoma.
Can Mucinous Lesions of the Breast Be Reliably Diagnosed by Core Needle Biopsy? Andrew A. Renshaw, MD	Am J Clin Pathol 2002;118:82-84 Abstract quote Lesions of the breast containing extravasated mucin span a continuum from benign mucoceles to invasive mucinous (colloid) carcinoma. It is well known that distinguishing benign from malignant mucinous lesions is difficult in fine-needle aspiration material. Whether these lesions also are difficult to distinguish in core needle biopsy material is not known. To address this, I reviewed the results of 4,297 breast core needle biopsies. Mucinous lesions were identified in 22 cases (0.51%), and excisional biopsy material was available for 15 of these. At excision, 0 of 8 benign mucinous lesions showed carcinoma, while 7 of 7 mucinous lesions associated with carcinoma at the time of core needle biopsy showed carcinoma at excision. The vast majority of mucinous lesions of the breast can be diagnosed accurately by core needle biopsy. Whether all such lesions require excision is not known at this time.
VARIANTS

PROGNOSIS AND TREATMENT	CHARACTERIZATION
PROGNOSTIC FACTORS
GENERAL
Pure mucinous carcinoma of the breast: a clinicopathologic correlation study. Avisar E, Khan MA, Axelrod D, Oza K. Department of Surgery, Beth Israel Medical Center, New York, New York, USA.	Ann Surg Oncol 1998 Jul-Aug;5(5):447-51 Abstract quote BACKGROUND: Pure mucinous carcinoma (PMC) of the breast has a better prognosis than does invasive ductal carcinoma not otherwise specified and is more prevalent in older patients. We investigated the correlation between prognostic indices and clinical outcome in this histologic subset. METHODS: A retrospective review was done of patients with PMC treated between 1989 and 1996. Demographic data, pathologic indices of prognosis, axillary nodal status, and outcome were assessed. RESULTS: Out of 6083 cases of breast carcinoma, 30 were PMC. Only 3 of 25 (12%) axillary dissections were positive. The average age of the group with positive nodes was 57 years, as compared to 69.5 years (95% CI; 63.24-75.76) in the group with negative nodes. All the tumors with positive nodes were aneuploid and had a high nuclear grade, compared to a 31.25% aneuploidy rate in the group without nodal disease (P = .058). Negative ER receptors were found in only 2 of 20 (10%) of the patients tested. Both had axillary disease (P = .016). Tumor size did not correlate with axillary metastasis. Two of the 29 patients died from unrelated diseases. The other 27 patients are alive with no evidence of disease. CONCLUSIONS: Axillary nodal disease is rare in PMC and correlates with a younger age, aneuploidy, high nuclear grade, or a negative ER receptor status. Sentinel lymph node biopsy may help identify the need for axillary dissection.
RECURRENCE
Mucinous carcinoma of the breast: recurrence 30 years after mastectomy. Scharnhorst D, Huntrakoon M. Department of Pathology and Oncology, University of Kansas Medical Center, Kansas City 66103.	South Med J 1988 May;81(5):656-7 Abstract quote We have reported a case of mucinous breast carcinoma that recurred in the form of lung and lymph node metastases 30 years after definitive resection. This case emphasizes the indolent nature of this neoplasm and the need to lengthen the period of follow-up for patients with this form of cancer.
STAGING
Pure mucinous carcinoma of the breast: is axillary staging necessary? Paramo JC, Wilson C, Velarde D, Giraldo J, Poppiti RJ, Mesko TW. Department of Surgery, Mount Sinai Medical Center, Miami Beach, Florida 33140, USA.	Ann Surg Oncol 2002 Mar;9(2):161-4 Abstract quote BACKGROUND: Mucinous carcinoma of the breast (MCB) may be associated with a low risk of axillary metastases. METHODS: To evaluate the incidence of axillary nodal metastasis in MCB, a review of all cases from January 1990 to July 2000 was performed. Pure MCB was defined as all tumor cells being completely surrounded by mucin. Patient demographics, tumor size, estrogen receptor status, total number of dissected lymph nodes, and incidence of nodal metastasis were studied. Deeper sections on the lymph nodes from the pure tumors were performed and stained with low-molecular cytokeratin. RESULTS: Nineteen cases of pure MCB and 41 cases of mixed MCB were identified. Patients with pure MCB were older than those with mixed MCB. Tumor size and estrogen receptor status showed no statistically significant differences between the two groups. None of the patients with pure MCB demonstrated lymph node metastases, whereas 12 of 41 cases with mixed MCB demonstrated metastatic lymph node involvement. CONCLUSIONS: Because pure MCB seems unlikely to metastasize, axillary lymph node staging in these patients may not be necessary. The presence of lymph node metastases strongly indicates the presence of a mixed MCB.
TREATMENT
Pathological features of mucinous carcinoma of the breast are favourable for breast-conserving therapy. Anan K, Mitsuyama S, Tamae K, Nishihara K, Iwashita T, Abe Y, Ihara T, Nakahara S, Katsumoto F, Toyoshima S. Department of Surgery, Kitakyushu Municipal Medical Centre, Kitakyushu, Fukuoka 802-0077, Japan.	Eur J Surg Oncol 2001 Aug;27(5):459-63 Abstract quote AIM: The effectiveness of breast-conserving therapy for mucinous carcinoma has not been well documented. We examined clinical and pathological features of cases to determine whether patients with mucinous carcinoma were suitable candidates for this treatment. METHOD: Cases of pure type (n=52) and mixed type (n=24) mucinous carcinomas were reviewed with emphasis on the risk factors associated with local recurrences after breast-conserving therapy. RESULTS: Large pure mucinous carcinomas had a low incidence of extensive intraductal spreading (EIS). An inverse correlation existed between the incidence of EIS and tumour size (P<0.05). Comedo type EIS was infrequent (11%) in pure mucinous carcinoma. Incidences of lymphatic vessel invasion (4%) and nodal involvement (4%) were lower in pure mucinous carcinoma than in mixed carcinoma (P<0.05). No nodal involvement occurred in patients with pure mucinous carcinoma less than 3 cm in diameter. CONCLUSIONS: Patients with pure mucinous carcinomas, except those invading the local skin, are suitable candidates for breast-conserving therapy. Most pure mucinous carcinomas, including a large tumour up to 5 cm in diameter, can be treated with this therapy.

Epidemiology
Disease Associations
Pathogenesis
Laboratory/Radiologic/Other Diagnostic Testing
Gross Appearance and Clinical Variants
Histopathological Features and Variants
Special Stains/Immunohistochemistry/Electron Microscopy
Differential Diagnosis
Prognosis and Treatment
Commonly Used Terms

EPIDEMIOLOGY	CHARACTERIZATION
SYNONYMS	Mucinous carcinoma Colloid carcinoma
INCIDENCE	7% of tumors in women 75 years or older
AGE RANGE-MEDIAN	Usually older than nonmucinous tumors

GROSS APPEARANCE/ CLINICAL VARIANTS	CHARACTERIZATION
GENERAL
VARIANTS
ADVANCED
Locally advanced mucinous carcinoma of the breast with sudden growth acceleration: a case report. Ishikawa T, Hamaguchi Y, Ichikawa Y, Shimura M, Kawano N, Nakatani Y, Ohnishi H, Maegawa J, Ogino I, Shimada H. Department of Surgery, Yokohama City University, School of Medicine, Yokohama, Japan.	Jpn J Clin Oncol 2002 Feb;32(2):64-7 Abstract quote We report a 35-year-old woman with locally advanced mucinous carcinoma of the breast with sudden growth acceleration. A pea-sized mass developed into an ulcerated large tumor within 1 month. After the combination of chemotherapy, radiation and hyperthermia, a radical mastectomy was performed, followed by repair of the skin defect by latissimus dorsi and rectus abdominis musculocutaneous flaps. Histological examination revealed a pure mucinous carcinoma with axillary lymph node involvement. Estrogen and progesterone receptors were not detected in the tumor. Twenty-five months after treatment, there is no sign of recurrent disease. Pure mucinous carcinoma generally has a less aggressive growth pattern as defined by tumor size, adherence to the overlying skin/bottom fasciae, estrogen and progesterone receptor positive and primary lymph axillary lymph node metastases. This case showed completely opposite features to all of these typical biological features of pure mucinous carcinomas.

SPECIAL STAINS/IMMUNOPEROXIDASE/ OTHER	CHARACTERIZATION
SPECIAL STAINS
Mucinous (colloid) adenocarcinomas secrete distinct O-acylated forms of sialomucins: a histochemical study of gastric, colorectal and breast adenocarcinomas. Saez C, Japon MA, Poveda MA, Segura DI. Laboratory of Histochemistry, Department of Pathology, Hospital Universitario Virgen del Rocio, Avenida Manuel Siurot s/n, Seville 41013, Spain.	Histopathology 2001 Dec;39(6):554-60 Abstract quote AIMS: Mucinous (colloid) adenocarcinomas represent a distinct group of tumours defined by the presence of large amounts of extracellular mucins. By using histochemical methods, we analysed mucins secreted by mucinous versus non-mucinous adenocarcinomas and looked for differential secretion profiles. METHODS AND RESULTS: Sixty-four adenocarcinomas were studied (23 colorectal, 17 gastric, and 24 breast tumours). Thirty-two tumours were of the colloid type. The following methods were applied to paraffin tissue sections: (i) Alcian blue (pH 2.5) and periodic acid-Schiff (PAS); (ii) high iron diamine and Alcian blue (pH 2.5); (iii) periodic acid borohydride, potassium hydroxide, and PAS; (iv) periodic acid-thionine Schiff, potassium hydroxide, and PAS; and (v) periodic acid-borohydride and PAS. Most adenocarcinomas secreted acidic mucins, with sialomucins predominating over sulfomucins, except for non-mucinous adenocarcinomas of the breast which showed predominant neutral mucins. All mucinous adenocarcinomas contained C9-O-acyl sialic acid as mono, di(C8,C9)-, or tri(C7,C8,C9)-O-acyl forms. Acidic mucins secreted by the majority of non-colloid adenocarcinomas consisted of non-O-acylated sialomucins. CONCLUSIONS: C9-O-acylation of sialic acid is a characteristic feature of mucinous adenocarcinomas and can be readily detected by histochemical methods.
IMMUNOPEROXIDASE