Lumps can occur in the breast during lactation, which usually puts the woman on alert. A thorough anamnesis is essential to know the cause of the complaint and its treatment. The most common causes of lumps are duct obstruction, breast abscess, and galactocele.

Obstructions of the duct are due to stasis of milk caused by difficulties in the milk let-down due to suboptimal breastfeeding technique. In addition, pressure may be performed on the duct, for example, the pressure applied by wired bras, a possible situation of infection, or the baby’s suboptimal suction. Blockages can get further complicated by acute mastitis if they are not treated adequately. Typically this occurs on one side, does not produce fever, and the patient describes the presence of lumps with discomfort. Often, they also report a sensation of non-emptying of the breast.

A breast abscess is a complication of acute mastitis. The patient usually describes feeling a hard, defined, fluctuating lump. On examination, there is an erythematous area and shiny skin with a weak appearance.

As for the galactocele, this is a benign process and is due to an accumulation of lipid material from the milk outside the ducts. It forms a cyst retained within the mammary stroma, with no exit to the nipple, and can occur in any breast area.

Depending on the location and size of the galactocele, it can complicate the milk ejection. It does not change its size after a feed and is not usually accompanied by pain or fever. It can be recurrent, both in the current lactation, as well as in subsequent lactations.

When a lump is diagnosed, these are the recommendations:

In the case of obstructions, an entire feed should be observed, and the baby’s mouth should be examined for limitations to achieve a deep, optimal latch. Frequent emptying of the breast is recommended, facilitating milk exit with a gentle circular massage over the hardened area. Position the baby so that his or her chin points towards the hardened area. Apply cold on the area, and oral anti-inflammatory medication can be prescribed if necessary.

A breast abscess requires rapid diagnosis and treatment with drainage by ultrasound-guided puncture or by surgical incision and subsequent antibiotic treatment according to the antibiogram. The option chosen will depend on the location and size of the abscess and on the mother’s decision. It is essential to ensure milk removal as part of the treatment, either with the newborn placed directly to the breast or with the help of hand expressing or breast pumping, so if a surgical approach is used, the incision should be far away from the areola.

As for a galactocele, a watchful waiting attitude can be maintained, controlling that it does not interfere with milk supply or ejection. If any treatment is proposed, the drainage through ultrasound-guided aspiration would be recommended. However, a relapse is frequent, in addition to having an increased risk of infection.

Lumps that do not disappear within 72 hours after their discovery should be evaluated by the relevant physician, usually in the Gynaecology Department, with the support of ultrasound imaging. Ultrasound scans are compatible with breastfeeding and facilitate the exploration of the lactating breast. To optimize the examination, it is advisable to empty the breast before the examination, either by suction of the baby or by removing milk manually or with a pump.

Remember, there are lumps unrelated to breastfeeding, either benign or malignant. On many occasions, diagnosis and typing of the tumors that occur during the lactation period are delayed, with a consequent increase in the situation’s complexity.