Cystic Echinococcosis is a major public health problem in our country, distributed in both humans and animals. It is caused by the larval form of Echinococcus granulosus. Humans are accidental intermediate hosts of this organism.1 Breast involvement is rare, accounting for only 0.27%2 of the localisations. The objective of reporting the case is its rare involvement, inability to diagnose on fine needle aspiration cytology and confirming the diagnosis on the basis of paraffin sectioning and followed by a discussion on the pertinent clinical aspects.

Mrs. SDM, age 75 years, housewife non-vegetarian, cattle rearing and working in farms, presented in OPD with H/O left breast lump since 12 years with pain. To start with lump was noticed at left axillary tail, later extended into the upper and lower quadrant of left breast.

No H/O trauma, fever, cough, dyspnoea and abdominal pain. Bowel and bladder habits were normal.

H/O eating raw vegetables

No H/O nipple discharge

O/E left breast show

• Cystic swelling occupying left upper outer quadrant extending into the axillary tail.
• Tender on deep palpation
• No change in size of swelling, on pulling pectoralis major muscle on contraction.
• Skin over lump pinchable
• Fluctuation +ve
• Transillumination +ve
• Surface smooth
• All borders well demarcated
• Non mobile
• Left axillary lymph node, central single non-tender firm 1 x 2 cm lymph node palpable.
• Right breast and axilla normal.

Laboratory investigation

CBC, ESR, Stool examination Within Normal
Routine urine examination Limits
Blood Sugar, LFT Creatinine BUN,
FNAC Breast Serous disease
of breast
USG Abdomen Cholelithiasis

Pre-operative provisional diagnosis

Phylloid tumour/serious cystic disease of breast

Operative notes

• Operative notes
• Radial incision taken over the lump, till the capsule of the lump.
• Transparent cystic wall noted
• Cavity was approximated with chromic catgut 0/1 with corrugated rubber drain.
• Haemostasis maintained

  Fig. 1 : Showing the gross specimen

Specimen cut open, daughter cyst with hydatid fluid was noted and sent for paraffin section. Histopathology report confirmed the diagnosis of Hydatid Cyst of Left Breast.

Hydatid disease of breast is rare and can be a part of disseminated echinococcosis. In spite of its rareness, primary breast involvement (Fig. 1) constitutes a differential diagnosis of breast lump in endemic areas2 for cystic echinococcosis of breast.
Usually occurs in female age group between 30 and 50 years of age but in our patient the age group was much more wider. It usually presents as slow, progressive, painless lump without any specific signs and symptoms.2,3 Pre-operatively fine needle aspiration cytology (FNAC) did not reveal the diagnostic hooklets or the laminated membrane. Two pricks at different sites were given and 20-30 ml of clear fluid was aspirated and subjected to staining by various stains viz H and E, (Fig. 2) pap stain, giemsa stain and Field staining was done by heat fixing the smear which did not reveal any significant cytological finding, and we reported it as serous cystic disease of breast.4 During the process of fine needle aspiration there was no anaphylactic reactions seen as a complication of this procedure.5 This supports the importance of wide and routine use of fine needle aspiration cytology in patients undergoing excision for clinically, obvious fibroadenoma, fibrocystic disease of breast, cyst phylloid sarcoma.

Fig. 2 : H and E section	Fig. 3 : ZNCF stain showing hooklets

Mammography, MRI, ultrasonography6,7 of contralateral breast and abdomen should be done pre-operatively and post operatively to rule out dissemination in other organs. Serological testing for antibodies by indirect haemagglutination test and level of IgG should be helpful especially post operatively to know the delayed type of hypersensitive reactions. Since the reaction usually may be immediate or slow, there is progressive reaction after 2 to 10 years of persistence of the echinococcus cyst.

In our patient cystectomy was preferred and the diagnosis was confirmed by histopathology study, and demonstration of hooklets by staining the smear by Ziehl Neelsen method revealed pink coloured hooklets (Fig. 3) as a supportive clue for the final diagnosis of hydatidosis of breast.8

Hydatid disease still represents an important medical and surgical problem in many regions and a challenge in common practice world wide. We have ruled out the commonly affected organs like liver and lung, because the parasite passes through the hepatic filter first and pulmonary filter thereafter.

Affected sites reported in the literature include adrenal glands, muscles and ligaments, mesentery, thymus, uterus, bone, brain, kidney, heart, breast, spleen, pancreas, seminal vesicles, pericardium and subcutaneous tissue.

We have given antiparasitic medication before and after surgery to reduce cyst size and for elimination of parasite. The mechanism is probably through blockade of the glucose intake and glycogen deprivation of the parasite with growth retardation and to a certain extent sterilizing the content to avoid reaction. But the antiparasitic agent is not the sole therapeutic agent to prevent further implants.9

Since echinococcosis in humans is a zoonotic infection, a new option for the control of echinococcosis in the intermediate population (cattle, dog, etc.) is vaccination.10 In our patient an association could be found between ingestion of raw vegetables, cattle rearing and hydatidosis.11 Finally we would suggest or stress for post operative follow up, during which IgG antibody response would provide the best correlate of disease activity.12

We express our gratitude to Dr. (Mrs.) Manju Sadaranjani, Supdt. and Dr. KK Mehta, HOD, Surgery Department of VN Desai Mun Gen Hospital for allowing us to publish the Hospital data.

Mrs. Uma A Clerk of RRI (H) helped to prepare the manuscript.